Search results
Search for "antitumor agents" in Full Text gives 34 result(s) in Beilstein Journal of Organic Chemistry.
Reactivity of hypervalent iodine(III) reagents bearing a benzylamine with sulfenate salts
- Beatriz Dedeiras,
- Catarina S. Caldeira,
- José C. Cunha,
- Clara S. B. Gomes and
- M. Manuel B. Marques
Beilstein J. Org. Chem. 2024, 20, 3281–3289, doi:10.3762/bjoc.20.272
- , commonly referred to as sulfa drugs. These include top seller drugs, e.g., antimicrobials, anti-inflammatories, antihypertensives, and antitumor agents [24][25][26]. Particularly, the sulfonamide motif can act as a bioisostere of carboxylic acids, establishing a set of hydrogen bonds similar to those
Graphical Abstract
Figure 1: Examples of cyclic HIRs with a nitrogen-based group transfer [4,10,13-20].
Scheme 1: Electrophilic α‑amination of indanone-based β-ketoesters [4].
Scheme 2: Scope of the different (benzylamino)benziodoxolones (BBXs) 2 with ORTEP-3 diagram of compound 2d, u...
Scheme 3: Scope of the different β-sulfinyl esters 4 [32,33]. Isolated yields. rt – room temperature.
Scheme 4: Scope of the primary amine electrophilic reaction of sulfenate salts. Reaction conditions: 4 (2 equ...
Scheme 5: Electrophilic amination reaction in the presence of TEMPO. Reaction conditions: 4a (2 equiv), NaH (...
Scheme 6: Mechanism proposed for sulfonamide 5, β-sulfinyl ester 4, disulfide 7, and sulfide 3 formations. Th...
A facile three-component route to powerful 5-aryldeazaalloxazine photocatalysts
- Ivana Weisheitelová,
- Radek Cibulka,
- Marek Sikorski and
- Tetiana Pavlovska
Beilstein J. Org. Chem. 2024, 20, 1831–1838, doi:10.3762/bjoc.20.161
- artificial systems. Additionally, 5-deazaflavins have emerged as prospective antitumor agents [9][10]. Surprisingly, among the broad family of flavin derivatives, 5-deazaalloxazines have received less attention regarding their photophysical properties, despite their close similarity to the above-mentioned 5
Graphical Abstract
Figure 1: (A) The general structures of isoalloxazine (flavin, Fl), alloxazine (All), 5-deazaisoalloxazine (5...
Scheme 1: Three-component condensation of anilines, aldehydes and N,N-dimethylbarbituric acid. aReaction was ...
Figure 2: UV–vis absorption spectra of 5-arydeazaalloxazines 2f, 2j and 2n in DMF (l = 1 cm, c = 2.50 × 10−5 ...
Scheme 2: Control experiments related to bulky substituted aldehydes.
Synthesis of 5-arylidenerhodanines in L-proline-based deep eutectic solvent
- Stéphanie Hesse
Beilstein J. Org. Chem. 2023, 19, 1537–1544, doi:10.3762/bjoc.19.110
- -competitive PI3Kγ inhibitors [7]. A few years ago, we worked intensively on 2-heteroarylimino-1,3-thiazolidin-4-ones as potential antitumor agents [8] and we demonstrated that derivative F was an interesting CDC25A inhibitor [9]. Up to now, the synthesis of most organic compounds still uses harmful reagents
Graphical Abstract
Figure 1: Examples of rhodanines and related five-membered heterocycles with interesting biological activitie...
Scheme 1: Synthesis of 5-benzylidenerhodanine derivatives. Conditions: areaction performed for 3 h at 60 °C. b...
Synthesis of ether lipids: natural compounds and analogues
- Marco Antônio G. B. Gomes,
- Alicia Bauduin,
- Chloé Le Roux,
- Romain Fouinneteau,
- Wilfried Berthe,
- Mathieu Berchel,
- Hélène Couthon and
- Paul-Alain Jaffrès
Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96
- antitumor agents but without discussing the synthesis approaches, are complementary to the synthesis aspects presented in the upcoming section. 2.1 Synthesis of edelfosine Edelfosine (1-O-octadecyl-2-O-methylglycero-3-phosphocholine) ET-18-OCH3 or ET-16-OCH3 is an alkyl ether lipid with a methoxy group in
Graphical Abstract
Figure 1: Chemical structure of some natural ether lipids (ELs).
Figure 2: Synthesis of lyso-PAF and PAF from 1-O-alkylglycerol [64].
Figure 3: Synthesis of lyso-PAF from 1,3-benzylideneglycerol 3.1 [69].
Figure 4: A) Synthesis of the two enantiomers of octadecylglycerol (4.6 and 4.10) from ᴅ-mannitol (4.1); B) s...
Figure 5: Four-step synthesis of PAF 5.6 from (S)-glycidol [73].
Figure 6: Synthesis of 1-O-alkylglycerol A) from solketal, B) from ᴅ- or ʟ-tartaric acid and the intermediate ...
Figure 7: Synthesis of EL building blocks starting from substituted glycidol 7.1a–c [82].
Figure 8: Synthesis of PAF 8.5 by using phosphoramidite 8.2 [86].
Figure 9: Synthesis of oleyl-PAF 9.7 from ʟ-serine [88].
Figure 10: Synthesis of racemic analogues of lyso-PAF 10.8 and PAF 10.9 featuring a phenyl group between the g...
Figure 11: Synthesis of racemic deoxy-lyso-PAF 11.7 and deoxy-PAF 11.8 [91].
Figure 12: Synthesis of racemic thio-PAF 12.8 [93].
Figure 13: Racemic synthesis of 13.6 to illustrate the modification of the glycerol backbone by adding a methy...
Figure 14: Racemic synthesis of 14.5 as an illustration of the introduction of methyl substituents on the glyc...
Figure 15: Synthesis of functionalized sn-2-acyl chains of PC-EL; A) Steglich esterification or acylation reac...
Figure 16: Synthesis of racemic mc-PAF (16.3), a carbamate analogue of PAF [102].
Figure 17: A) Synthesis of (R)-17.2 and (S)-17.6 starting from (S)-solketal (17.1); B) synthesis of N3-PAF (17...
Figure 18: Modification of the phosphocholine polar head to produce PAF analogues [81].
Figure 19: Racemic PAF analogues 19.3 and 19.5 characterized by the absence of the phosphate group [107].
Figure 20: Synthesis of PIP3-PAF (20.7) [108].
Figure 21: Large-scale synthesis of C18-edelfosine (21.8) [116].
Figure 22: Synthesis of C16-edelfosine (22.10) starting from isopropylidene-ʟ-glyceric acid methyl ester (22.1...
Figure 23: Phosphocholine moiety installation by the use of chlorophosphite 23.2 as key reagent [119].
Figure 24: Synthesis of rac-1-alkyl-2-O-methylglycerol (AMG) [120].
Figure 25: Synthesis of stereocontrolled 1-alkyl-2-O-methyl glycerol 25.9 (AMG) from dimethyl ᴅ-tartrate [81].
Figure 26: A) Racemic synthesis of thioether 26.4 [129,130], B) structure of sulfone analogue 26.5 [129].
Figure 27: Stereocontrolled synthesis of C18-edelfosine thioether analogue 27.8 [118].
Figure 28: Synthesis of thioether 28.4 that include a thiophosphate function [134].
Figure 29: Synthesis of ammonium thioether 29.4 and 29.6 [135].
Figure 30: Synthesis of the N-methylamino analogue of edelfosine 30.6 (BN52211) [138].
Figure 31: Synthesis of 1-desoxy analogues of edelfosine; A) with a saturated alkyl chain; B) synthesis of the...
Figure 32: Stereocontrolled synthesis of edelfosine analogue (S)-32.8 featuring a C18:1 lipid chain [142].
Figure 33: Synthesis of edelfosine analogues with modulation of the lipid chain; A) illustration with the synt...
Figure 34: Synthesis of phospholipid featuring a carbamate function to link the lipid chain to the glycerol un...
Figure 35: Synthesis of sesquiterpene conjugates of phospho glycero ether lipids [148].
Figure 36: Racemic synthesis of methyl-substituted glycerol analogues 36.7 and 36.10: A) synthesis of diether ...
Figure 37: Racemic synthesis of ilmofosine (37.6) [155,156].
Figure 38: A) Stereoselective synthesis of 38.5 via a stereoselective hydroboration reaction; B) synthesis of ...
Figure 39: Racemic synthesis of SRI62-834 (39.6) featuring a spiro-tetrahydrofurane heterocycle in position 2 ...
Figure 40: Racemic synthesis of edelfosine analogue 40.5 featuring an imidazole moiety in sn-2 position [160].
Figure 41: Racemic synthesis of fluorine-functionalized EL: A) Synthesis of 41.6 and B) synthesis of 41.8 [161-163].
Figure 42: A) Synthesis of the β-keto-ester 42.6 that also features a decyl linker between the phosphate and t...
Figure 43: Synthesis of phosphonate-based ether lipids; A) edelfosine phosphonate analogue 43.7 and B) thioeth...
Figure 44: Enantioselective synthesis of phosphonates 44.3 and 44.4 [171].
Figure 45: Racemic synthesis of phosphinate-based ether lipid 45.10 [172].
Figure 46: Racemic synthesis of edelfosine arsonium analogue 46.5 [173].
Figure 47: Synthesis of edelfosine dimethylammonium analogue 47.2 [118].
Figure 48: Synthesis of rac-C18-edelfosine methylammonium analogue 48.4 [176].
Figure 49: A) Synthesis of edelfosine N-methylpyrrolidinium analogue 49.2 or N-methylmorpholinium analogue 49.3...
Figure 50: A) Synthesis of edelfosine’s analogue 50.4 with a PE polar group; B) illustration of a pyridinium d...
Figure 51: A) Synthesis of 51.4 featuring a thiazolium cationic moiety; B) synthesis of thiazolium-based EL 51...
Figure 52: Synthesis of cationic ether lipids 52.3, 52.4 and 52.6 [135,183].
Figure 53: Synthesis of cationic carbamate ether lipid 53.5 [184].
Figure 54: Synthesis of cationic sulfonamide 54.5 [185].
Figure 55: Chemical structure of ONO-6240 (55.1) and SRI-63-119 (55.2).
Figure 56: Synthesis of non-ionic ether lipids 56.2–56.9 [188].
Figure 57: Synthesis of ether lipid conjugated to foscarnet 57.6 [189].
Figure 58: A) Synthesis of ether lipid conjugated to arabinofuranosylcytosine; B) synthesis of AZT conjugated ...
Figure 59: Synthesis of quercetin conjugate to edelfosine [191].
Figure 60: Synthesis of 60.8 (Glc-PAF) [194].
Figure 61: A) Synthesis of amino ether lipid 61.7 functionalized with a rhamnose unit and its amide analogue 6...
Figure 62: A) Synthesis of glucose ether lipid 62.4; B) structure of ether lipid 62.5 possessing a maltose uni...
Figure 63: A) Synthesis of glucuronic methyl ester 63.8; B) structure of cellobiose 63.9 and maltose 63.10 ana...
Figure 64: A) Synthesis of maltosyl glycerolipid 64.7; B) structure of lactose analogue 64.8 prepared followin...
Figure 65: A) Asymmetric synthesis of the aglycone moiety starting from allyl 4-methoxyphenyl ether; B) glycos...
Figure 66: A) Synthesis of ohmline possessing a lactose moiety. B) Structure of other glyco glycero lipids pre...
Figure 67: A) Synthesis of lactose-glycerol ether lipid 67.5; B) analogues possessing a maltose (67.6) or meli...
Figure 68: Synthesis of digalactosyl EL 68.6, A) by using trityl, benzyl and acetyl protecting groups, B) by u...
Figure 69: A) Synthesis of α-ohmline; B) structure of disaccharide ether lipids prepared by using similar meth...
Figure 70: Synthesis of lactose ether lipid 70.3 and its analogue 70.6 featuring a carbamate function as linke...
Figure 71: Synthesis of rhamnopyranoside diether 71.4 [196].
Figure 72: Synthesis of 1-O-hexadecyl-2-O-methyl-3-S-(α-ᴅ-1'-thioglucopyranosyl)-sn-glycerol (72.5) [225].
Figure 73: A) Preparation of lipid intermediate 73.4; B) synthesis of 2-desoxy-C-glycoside 73.10 [226].
Figure 74: Synthesis of galactose-pyridinium salt 74.3 [228].
Figure 75: Synthesis of myo-inositol derivative Ino-C2-PAF (75.10) [230].
Figure 76: A) Synthesis of myo-inositol phosphate building block 76.7; B) synthesis of myo-inositolphosphate d...
Figure 77: A) Synthesis of phosphatidyl-3-desoxy-inositol 77.4; B) synthesis of phosphono-3-desoxyinositol 77.9...
Figure 78: A) Structure of diether phosphatidyl-myo-inositol-3,4-diphosphate 78.1; B) synthesis of phosphatidy...
Figure 79: A) Synthesis of diether-phosphatidyl derivative 79.4 featuring a hydroxymethyl group in place of a ...
Figure 80: Synthesis of Glc-amine-PAF [78].
Figure 81: Synthesis of glucosamine ether lipid 81.4 and its analogues functionalized in position 3 of the ami...
Figure 82: Synthesis of fully deprotected aminoglucoside ether lipid 82.5 [246].
Figure 83: Synthesis of C-aminoglycoside 83.12 using Ramberg–Bäcklund rearrangement as a key step [250].
Figure 84: A) List of the most important glyco lipids and amino glyco lipids included in the study of Arthur a...
Figure 85: Synthesis of mannosamine ether lipid 85.6 [254].
Figure 86: A) Synthesis of glucosamine ether lipids with a non-natural ʟ-glucosamine moiety; B) synthesis of e...
Figure 87: A) Structure of the most efficient anticancer agents 87.1–87.4 featuring a diamino glyco ether lipi...
Figure 88: A) Synthesis of diamino glyco ether lipid 87.4; B) synthesis of bis-glycosylated ether lipid 88.10 [256]....
Figure 89: Synthesis of triamino ether lipid 89.4 [260].
Figure 90: Synthesis of chlorambucil conjugate 90.7 [261].
Figure 91: Three main methods for the preparation of glycerol ether lipid 91.3; A) from solketal and via a tri...
Figure 92: Four different methods for the installation of the phosphocholine polar head group; A) method using...
Figure 93: Illustration of two methods for the installation of saccharides or aminosaccharides; A) O-glycosyla...
Photoredox catalysis harvesting multiple photon or electrochemical energies
- Mattia Lepori,
- Simon Schmid and
- Joshua P. Barham
Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81
Graphical Abstract
Figure 1: Oxidative and reductive activations of organic compounds harvesting photoredox catalysis.
Figure 2: General catalytic cycles of radical ion conPET (left) and radical ion e-PRC (right).
Figure 3: “Beginner’s guide”: comparison between advantages, capacities, and prospectives of conPET and PEC.
Figure 4: A) conPET reductive dehalogenation of aryl halides with PDI. B) Reductive C–H arylation with pyrrol...
Figure 5: A) Chromoselective mono- and disubstitution or polybrominated pyrimidines with pyrroles. B) Sequent...
Figure 6: A) Synthesis of pyrrolo[1,2-a]quinolines. B) Synthesis of ullazines.
Figure 7: A) Reductive phosphorylation of aryl halides via conPET. B) Selected examples from the substrate sc...
Figure 8: A) Reductive dehalogenation of aryl halides via conPET and selected examples from the substrate sco...
Figure 9: A) Reductive C–H arylation of aryl halides via conPET (top) and selected examples from the substrat...
Figure 10: A) Reductive hydrodehalogenation of aryl halides with Mes-Acr-BF4. B) Selected examples from the su...
Figure 11: A) Reductive hydrodechlorination of aryl chlorides with 4-DPAIPN. B) Proposed formation of CO2•−. C...
Figure 12: A) Reductive conPET borylation with 3CzEPAIPN (top) and selected examples from the substrate scope ...
Figure 13: Scale-up of conPET phosphorylation with 3CzEPAIPN.
Figure 14: A) Borylation of 1d. B) Characteristics and structure of PC1 with green and red parts showing the l...
Figure 15: A) Reductive C–H arylation scope with polysulfide conPET (top) and selected examples from the subst...
Figure 16: Scale-up of A) C–H arylation and B) dehaloborylation with polysulfide photocatalysis in continuous-...
Figure 17: A) Formation of [Ir1]0 and [Ir2]0 upon PET between [Ir1]+ and Et3N. B) Mechanism of multi-photon ta...
Figure 18: A) Reductive hydrodehalogenation of aryl halides via multi-photon tandem photocatalysis. B) Selecte...
Figure 19: A) Carbonylative amidation of aryl halides in continuous flow. B) Selected examples from the substr...
Figure 20: A) General scheme for reductive (RQ) and oxidative quenching (OQ) protocols using [FeIII(btz)3](PF6)...
Figure 21: A) Carbonylative amidation of alkyl iodides with [IrIII(ppy)2(dtbbpy)]PF6. B) Selected examples fro...
Figure 22: A) Carboxylative C–N bond cleavage in cyclic amines. B) Selected examples from the substrate scope....
Figure 23: A) Formal reduction of alkenes to alkanes via transfer hydrogenation. B) Selected examples from the...
Figure 24: A) Birch-type reduction of benzenes with PMP-BPI. B) Selected examples from the substrate scope (sc...
Figure 25: Proposed mechanism of the OH− mediated conPET Birch-type reduction of benzene via generation of sol...
Figure 26: Reductive detosylation of N-tosylated amides with Mes-Acr-BF4. B) Selected examples from the substr...
Figure 27: A) Reductive detosylation of N-tosyl amides by dual PRC. B) Selected examples from the substrate sc...
Figure 28: A) Mechanism of the dual PRC based on PET between [Cu(dap)2]+ and DCA. B) Mechanism of the dual PRC...
Figure 29: A) N–O bond cleavage in Weinreb amides with anthracene. B) N–O bond cleavage in Weinreb amides rely...
Figure 30: A) Pentafluorosulfanylation and fluoride elimination. B) Mechanism of the pentafluorosulfanylation ...
Figure 31: A) α-Alkoxypentafluorosulfanylation (top) and selected examples from the substrate scope (bottom). ...
Figure 32: A) Oxidative amination of arenes with azoles catalyzed by N-Ph PTZ. B) Selected examples from the s...
Figure 33: A) C(sp3)–H bond activation by HAT via chloride oxidation by *N-Ph PTZ•+. B) Proposed mechanism for...
Figure 34: A) Recycling e-PRC C–H azolation of electron-rich arenes with pyrazoles using Mes-Acr+ as a photoca...
Figure 35: A) Radical ion e-PRC direct oxidation of unactivated arenes using TAC+ as an electro-activated phot...
Figure 36: A) Radical ion e-PRC direct oxidation of unactivated arenes using TPA as an electro-activated photo...
Figure 37: Proposed mechanism (top) and mode of preassembly (bottom).
Figure 38: A) Possible preassemblies of reactive (left) vs unreactive (right) arenes. B) Calculated spin densi...
Figure 39: A) Recycling e-PRC C(sp2 )–H acetoxylation of arenes using DDQ as a photocatalyst. B) Proposed cata...
Figure 40: Gram scale hydroxylation of benzene in a recirculated flow setup.
Figure 41: A) Radical ion e-PRC vicinal diamination of alkylarenes using TAC+ as an electro-activated photocat...
Figure 42: A) Sequential oxygenation of multiple adjacent C–H bonds under radical ion e-PRC using TAC+ as an e...
Figure 43: A) Enantioselective recycling e-PRC cyanation of benzylic C–H bonds using ADQS as photocatalyst. B)...
Figure 44: Proposed tandem mechanism by Xu and co-workers.
Figure 45: A) Enantioselective recycling e-PRC decarboxylative cyanation using Cu(acac)2, Ce(OTf)3 and a box l...
Figure 46: A) Enantioselective recycling e-PRC benzylic cyanation using Cu(MeCN)4BF4, box ligand and anthraqui...
Figure 47: A) Radical ion e-PRC acetoxyhydroxylation of aryl olefins using TAC+ as an electro-activated photoc...
Figure 48: Selected examples from the substrate scope.
Figure 49: Photoelectrochemical acetoxyhydroxylation in a recirculated flow setup.
Figure 50: A) Radical ion e-PRC aminooxygenation of aryl olefins using TAC+ as an electro-activated photocatal...
Figure 51: A) Recycling e-PRC C–H alkylation of heteroarenes with organic trifluoroborates using Mes-Acr+ as p...
Figure 52: A) Recycling e-PRC decarboxylative C–H alkylation of heteroarenes using CeCl3·7H2O as catalyst. B) ...
Figure 53: A) Recycling e-PRC decarboxylative C–H alkylation of heteroarenes using Fe(NH4)2(SO4)2·6H2O as cata...
Figure 54: A) Recycling e-PRC C–H alkylation of heteroarenes with alkyl oxalates and 4CzIPN as photocatalyst. ...
Figure 55: A) Recycling e-PRC decarboxylative C–H carbamoylation of heteroarenes using 4CzIPN as photocatalyst...
Figure 56: A) Photoelectrochemical HAT-mediated hydrocarbon activation via the chlorine radical. B) Proposed m...
Figure 57: A) Selected examples from the substrate scope. B) Gram and decagram scale semi-continuous flow PEC ...
Figure 58: A) Photoelectrochemical HAT-mediated dehydrogenative coupling of benzothiazoles with aliphatic C–H ...
Figure 59: A) Photoelectrochemical HAT activation of ethers using electro-activated TAC+ as photocatalyst. B) ...
Figure 60: Selected examples from the substrate scope.
Figure 61: A) Photoelectrochemical HAT-mediated synthesis of alkylated benzimidazo-fused isoquinolinones using...
Figure 62: A) Decoupled photoelectrochemical cerium-catalyzed oxydichlorination of alkynes using CeCl3 as cata...
Figure 63: Proposed decoupled photoelectrochemical mechanism.
Figure 64: A) Decoupled photoelectrochemical ring-opening bromination of tertiary cycloalkanols using MgBr2 as...
Figure 65: A) Recycling e-PRC ring-opening functionalization of cycloalkanols using CeCl3 as catalyst. B) Prop...
Figure 66: Selected examples from the substrate scope of the PEC ring-opening functionalization.
Figure 67: A) Radical ion e-PRC reduction of chloro- and bromoarenes using DCA as catalyst and various accepto...
Figure 68: A) Screening of different phthalimide derivatives as catalyst for the e-PRC reduction of aryl halid...
Figure 69: Screening of different organic catalysts for the e-PRC reduction of trialkylanilium salts.
Figure 70: A) e-PRC reduction of phosphonated phenols and anilinium salts. B) Selected examples from the subst...
Figure 71: A) ConPET and e-PRC reduction of 4-bromobenzonitrile using a naphthalene diimide (NDI) precatalyst ...
Figure 72: A) Radical ion e-PRC reduction of phosphinated aliphatic alcohols with n-BuO-NpMI as catalyst. B) C...
Figure 73: Selected examples from the substrate scope.
Figure 74: A) Recycling e-PRC reductive dimerization of benzylic chlorides using a [Cu2] catalyst. B) Proposed...
Figure 75: A) Decoupled photoelectrochemical C–H alkylation of heteroarenes through deamination of Katritzky s...
Figure 76: Proposed mechanism by Chen and co-workers.
Synthesis of imidazo[4,5-e][1,3]thiazino[2,3-c][1,2,4]triazines via a base-induced rearrangement of functionalized imidazo[4,5-e]thiazolo[2,3-c][1,2,4]triazines
- Dmitry B. Vinogradov,
- Alexei N. Izmest’ev,
- Angelina N. Kravchenko,
- Yuri A. Strelenko and
- Galina A. Gazieva
Beilstein J. Org. Chem. 2023, 19, 1047–1054, doi:10.3762/bjoc.19.80
- (PD404182) [1][2][3][4], sedative [5] and antitumor agents [6][7][8], as well as fungicides [9][10] and insecticides [11] have been found (Figure 1). The 1,3-thiazine heterocyclic system is comprised in some natural phytoalexins (cyclobrassinin, sinalbins A and B, rutalexin, and others) [12] and 7
Graphical Abstract
Figure 1: Examples of natural and synthetic bioactive 1,3-thiazine and imidazothiazolotriazine derivatives wi...
Scheme 1: Base-induced transformations and rearrangements of functionalized imidazo[4,5-e]thiazolo[3,2-b]-1,2...
Scheme 2: Alkaline hydrolysis of esters 1a,b. aDetermined by 1H NMR spectroscopy; bisolated yields.
Scheme 3: Synthesis of potassium imidazo[4,5-e][1,3]thiazino[2,3-c][1,2,4]triazine-7-carboxylates.
Scheme 4: Plausible rearrangement mechanism of imidazo[4,5-e]thiazolo[2,3-c][1,2,4]triazine 1d into imidazo[4...
Figure 2: 1H NMR spectra of the starting compound 1d (a) and the reaction mixture after 1.5 (b) and 4 (c) hou...
Scheme 5: Synthetic approaches to imidazo[4,5-e][1,3]thiazino[2,3-c][1,2,4]triazines 3a–d,j.
Scheme 6: Synthesis of imidazo[4,5-e][1,3]thiazino[2,3-c][1,2,4]triazine-7-carboxylic acids 5a–j.
Scheme 7: Synthesis of imidazo[4,5-e][1,3]thiazino[2,3-c][1,2,4]triazine-7-carboxylic acids 5k,m.
Scheme 8: Plausible path for the formation of products 9.
Figure 3: 1H NMR spectra of compounds 4a and 5a in DMSO-d6 in the region of 4.3–9.0 ppm.
Figure 4: 13C NMR GATED spectra of compounds 4a and 5a in DMSO-d6 in the region of 156.0–168.0 ppm.
Figure 5: General view of 5a in the crystal in thermal ellipsoid representation (p = 80%).
Synthesis of medium and large phostams, phostones, and phostines
- Jiaxi Xu
Beilstein J. Org. Chem. 2023, 19, 687–699, doi:10.3762/bjoc.19.50
- phostine derivatives, less attention has been paid to the synthesis of medium and large phostam, phostone, and phostine derivatives. They are also biologically active compounds, such as inhibitors of the human farnesyl pyrophosphate synthase [21][22], antitumor agents [23], and hapten for the production of
- bond formation through RCM reaction: Ring-closing metathesis (RCM) is an efficient strategy for the construction of common to large cyclic compounds via the formation of a C=C bond [26], which can be further reduced to a C–C bond. To prepare phostam-derived antitumor agents, ethyl N-allyl-N-(but-3-en-1
- -azaphosphocin-1(4H)-yl)acetate (4), respectively, in the presence of the Grubbs first generation catalyst via ring closing metathesis. The products 3 and 4 were further transformed to antitumor agents 5, 6, 9 and 10 through aminolysis with O-TMS hydroxylamine or hydrogenolysis followed by aminolysis with O-TMS
Graphical Abstract
Figure 1: Biologically active agents and chiral ligands containing medium and large phostams, phostones, and ...
Figure 2: Synthetic strategies for the preparation of medium and large phostams, phostones, and phostines.
Scheme 1: Synthesis of 1,2-azaphosphepine 2-oxide, 1,2-azaphosphocine 2-oxide, 1,2-azaphosphepane 2-oxide, an...
Scheme 2: Synthesis of bis[1,2]oxaphosphepine 2-oxide from tert-butyl 2-(bis(allyloxy)phosphoryl)pent-4-enoat...
Scheme 3: Synthesis of 2-ethoxy-5H-benzo[f][1,2]oxaphosphepine 2-oxides from 2-allylphenyl ethyl vinylphospho...
Scheme 4: Synthesis of 2-ethoxy-3,6-dihydrobenzo[g][1,2]oxaphosphocine 2-oxides from 2-allylphenyl ethyl ally...
Scheme 5: Synthesis of benzothiophene-fused 2-hydroxy-1,2-oxaphosphecane 2-oxide from (4-allyl-2-(4-methylphe...
Scheme 6: Synthesis of benzothiophene-fused 2-hydroxy-1,2-oxaphosphecane 2-oxide from benzyl hydrogen ((4-all...
Scheme 7: Synthesis of benzothiophene-fused 2-hydroxy-1-oxa-2-phosphacycloundecane 2-oxide from benzyl hydrog...
Scheme 8: Synthesis of 5,6,7-trihydro-1,2-oxaphosphepine 2-oxide and its benzo derivatives from 3-bromobut-3-...
Scheme 9: Synthesis of thieno[2,3-d]pyrimidine-fused 2-hydroxy-1,2-oxaphosphonane 2-oxide from benzyl hydroge...
Scheme 10: Synthesis of 3-phenoxybenzo[f]pyreno[1,10-cd][1,2]oxaphosphepine 3-oxide from diphenyl pyren-1-ylph...
Scheme 11: Synthesis of 1,2-oxaphosphepane 2-oxides and 1,2-oxaphosphocane 2-oxide from hydrogen methyl hex-5-...
Scheme 12: Synthesis of 2-methoxy-1,2-oxaphosphinane 2-oxides, 1,2-oxaphosphepine 2-oxides, 1,2-oxaphosphepane...
Scheme 13: Synthesis of 1,2-azaphosphepane 2-oxide and its benzo derivatives from 5-bromohex-5-en-1-yl methylp...
Scheme 14: Synthesis of 4-phenyl-1,2-dihydronaphtho[2,1-c][1,2]oxaphosphinine 4-oxide and 1-phenyl-3,4-dihydro...
Scheme 15: Synthesis of 2-alkoxy-3,5-dimethylene-1,2-oxaphosphepane 2-oxides from dialkyl 2-bromo-1-methylethy...
Scheme 16: Synthesis of 14-methyl-2-phenoxy-1-oxa-2-phosphacyclotetradecane 2-oxide from phenyl hydrogen (12-h...
Scheme 17: Synthesis of 5-oxo-1,3,5-trihydrobenzo[f][1,2]azaphosphepine 2-oxides from 1,2-dihydro-4H-benzo[d][...
Scheme 18: Synthesis of 3-hydrobenzo[f][1,2]oxaphosphepin-5(4H)-one 2-oxides from 2-phenyl/alkoxy-4H-benzo[d][...
Scheme 19: Synthesis of bicyclic seven- and eight-membered phosphotones from cycloalk-2-enones and dimethyl ph...
Scheme 20: Synthesis of binaphthylene-fused phosphotones from (M)-2'-methyl-[1,1'-binaphthalen]-2-ol and pheny...
Scheme 21: Synthesis of bicyclic phosphotone from (1S,2R)-2-methyl-3-(phenylsulfonyl)cyclohept-3-en-1-ol and d...
Synthetic strategies for the preparation of γ-phostams: 1,2-azaphospholidine 2-oxides and 1,2-azaphospholine 2-oxides
- Jiaxi Xu
Beilstein J. Org. Chem. 2022, 18, 889–915, doi:10.3762/bjoc.18.90
- generated phosphinimines 218 followed by quenching with water and sequential loss of two molecules of dimethylamine. However, the mechanism of this transformation was not clearly investigated (Scheme 35) [16]. To develop new antitumor agents composed of chromene and 5-oxo-1,2-azaphospolidine 2-oxide motifs
- to the cyano group followed by hydrolysis to give the final product 223 (Scheme 36). The product 223 showed antitumor activity in a biological assay [20]. To develop antioxidants and antitumor agents, the same group synthesized chromene-fused 5-oxo-1,2-azaphospholidine 2-oxide derivatives. The
Graphical Abstract
Figure 1: Biologically active 1,2-azaphospholine 2-oxide derivatives.
Figure 2: Diverse synthetic strategies for the preparation of 1,2-azaphospholidine and 1,2-azaphospholine 2-o...
Scheme 1: Synthesis of 1-phenyl-2-phenylamino-γ-phosphonolactam (2) from N,N’-diphenyl 3-chloropropylphosphon...
Scheme 2: Synthesis of 2-ethoxy-1-methyl-γ-phosphonolactam (6) from ethyl N-methyl-(3-bromopropyl)phosphonami...
Scheme 3: Synthesis of 2-aryl-1-methyl-2,3-dihydrobenzo[c][1,2]azaphosphole 1-oxides 13 from N-aryl-2-chlorom...
Scheme 4: Synthesis of 2,3-dihydrobenzo[c][1,2]azaphosphole 1-oxides from alkylarylphosphinyl or diarylphosph...
Scheme 5: Synthesis of 3-arylmethylidene-2,3-dihydrobenzo[c][1,2]azaphosphole 1-oxides via the TBAF-mediated ...
Scheme 6: Synthesis of 2-hydrobenzo[c][1,2]azaphosphol-3-one 1-oxides via the metal-free intramolecular oxida...
Scheme 7: Synthesis of 1,3-dihydrobenzo[d][1,2]azaphosphole 2-oxides 42 and 44 from ethyl/benzyl 2-bromobenzy...
Scheme 8: Synthesis of azaphospholidine 2-oxides/sulfide from 1,2-oxaphospholane 2-oxides/sulfides and 1,2-th...
Scheme 9: Synthesis of 1,3-dihydrobenzo[d][1,2]azaphosphole 2-oxides/sulfides from 2-aminobenzyl(phenyl)phosp...
Scheme 10: Synthesis of 1,3-dihydrobenzo[d][1,2]azaphosphole 2-sulfide (59) from zwitterionic 2-aminobenzyl(ph...
Scheme 11: Synthesis of 1,3-dihydrobenzo[d][1,2]azaphosphole 2-oxides from 2-aminobenzyl(methyl/phenyl)phosphi...
Scheme 12: Synthesis of ethyl 2-methyl-1,2-azaphospholidine-5-carboxylate 2-oxide 69 from 2-amino-4-(hydroxy(m...
Scheme 13: Synthesis of 2-methoxy-1,3-dihydrobenzo[d][1,2]azaphosphole 2-oxide 71 from dimethyl 2-(methylamino...
Scheme 14: Synthesis of tricyclic γ-phosphonolactams via formation of the P–C bond.
Scheme 15: Synthesis of γ-phosphonolactams 85 from ethyl 2-(3-chloropropyl)aminoalkanoates with diethyl chloro...
Scheme 16: Synthesis of N-phosphoryl- and N-thiophosphoryl-1,2-azaphospholidine 2-oxides 90/2-sulfides 91 from...
Scheme 17: Synthesis of 1-methyl-1,3-dihydrobenzo[d][1,2]azaphosphole 2-oxides 56a and 93 from P-(chloromethyl...
Scheme 18: Synthesis of 2-allylamino-1,5-dihydro-1,2-azaphosphole 2-oxides from N,N’-diallyl-vinylphosphonodia...
Scheme 19: Diastereoselective synthesis of 2-allylamino-1,5-dihydro-1,2-azaphosphole 2-oxides from N,N’-dially...
Scheme 20: Synthesis of 1-alkyl-3-benzoyl-2-ethoxy-1,3-dihydrobenzo[d][1,2]azaphosphole 2-oxides 106 from ethy...
Scheme 21: Synthesis of cyclohexadiene-fused γ-phosphinolactams from diphenyl-N-benzyl-N-methylphosphinamide (...
Scheme 22: Synthesis of cyclohexadiene-fused γ-phosphinolactams from diphenyl-N-alkyl-N-benzylphosphinamides.
Scheme 23: Synthesis of cyclohexadiene-fused γ-phosphinolactams from diphenyl-N-methyl-N-(1-phenylethyl)phosph...
Scheme 24: Synthesis of benzocyclohexadiene-fused γ-phosphinolactams from dinaphth-1-yl-N-alkyl-N-benzylphosph...
Scheme 25: Synthesis of benzocyclohexadiene-fused γ-phosphinolactams from dinaphth-1-yl-N-benzyl-N-methylphosp...
Scheme 26: Synthesis of carbonyl-containing benzocyclohexadiene-fused γ-phosphinolactams from dinaphth-1-yl-N-...
Scheme 27: Synthesis of benzocyclohexadiene-fused γ-phosphinolactams from dinaphthyl-N-benzyl-N-methylphosphin...
Scheme 28: Synthesis of cyclohexadiene-fused 1-(N-benzyl-N-methyl)amino-γ-phosphinolactams from aryl-N,N’-dibe...
Scheme 29: Synthesis of bis(cyclohexadiene-fused γ-phosphinolactam)s from bis(diphenyl-N-benzylphosphinamide)s....
Scheme 30: Synthesis of bis(hydroxymethyl-derived cyclohexadiene-fused γ-phosphinolactam)s from tetramethylene...
Scheme 31: Synthesis of 2-aryl/dimethylamino-1-ethoxy-2-hydrobenzo[c][1,2]azaphosphol-3-one 1-oxides from ethy...
Scheme 32: Synthesis of ethyl 2-ethoxy-1,2-azaphospholidine-4-carboxylate 2-oxides from ethyl 2-((chloro(ethox...
Scheme 33: Synthesis of (1S,3R)-2-(tert-butyldiphenylsilyl)-3-methyl-1-phenyl-2,3-dihydrobenzo[c][1,2]azaphosp...
Scheme 34: Synthesis of 2,3,3a,9a-tetrahydro-4H-1,2-azaphospholo[5,4-b]chromen-4-one (215) from 3-(phenylamino...
Scheme 35: Synthesis of quinoline-fused 1,2-azaphospholine 2-oxides from 2-azidoquinoline-3-carbaldehydes and ...
Scheme 36: Synthesis of 1-hydro-1,2-azaphosphol-5-one 2-oxide from cyanoacetohydrazide with phosphonic acid an...
Scheme 37: Synthesis of chromene-fused 5-oxo-1,2-azaphospolidine 2-oxides.
Scheme 38: Synthesis of (R)-1-phenyl-2-((R)-1-phenylethyl)-2-hydrobenzo[c][1,2]azaphosphol-3-one 1-oxide (239)...
Scheme 39: Synthesis of dihydro[1,2]azaphosphole 1-oxides from aryl/vinyl-N-phenylphosphonamidates and aryl-N-...
Scheme 40: Synthesis of 1,3-dihydro-[1,2]azaphospholo[5,4-b]pyridine 2-oxides.
Efficient N-arylation of 4-chloroquinazolines en route to novel 4-anilinoquinazolines as potential anticancer agents
- Rodolfo H. V. Nishimura,
- Thiago dos Santos,
- Valter E. Murie,
- Luciana C. Furtado,
- Leticia V. Costa-Lotufo and
- Giuliano C. Clososki
Beilstein J. Org. Chem. 2021, 17, 2968–2975, doi:10.3762/bjoc.17.206
- ) with relevant biological activities, is recognized as a privileged scaffold in medicinal chemistry [3][4]. Among important quinazoline derivatives, 4-anilinoquinazolines have been widely investigated as antitumor agents because they can inhibit some receptor tyrosine kinases (RTKs) expressed by
- antitumor agents, several synthetic methodologies have been developed to prepare these compounds. Amination using primary [6][8][9][10][11][12][13] or secondary [14][15][16] amines and 4-chloroquinazolines is among the most employed procedures. Electron-rich amines (e.g., primary aliphatic amines or hydroxy
- biologically active molecules are currently being investigated in our laboratories. Some antitumor agents containing the 4-anilinoquinazoline moiety. Examples of N-arylation reactions using 4-chloroquinazolines as substrates. Synthesis of verubulin analog. Synthesis of 4-chloro-6-halo-2-phenylquinazolines 8a
Graphical Abstract
Figure 1: Some antitumor agents containing the 4-anilinoquinazoline moiety.
Scheme 1: Examples of N-arylation reactions using 4-chloroquinazolines as substrates.
Scheme 2: Synthesis of verubulin analog.
Scheme 3: Synthesis of 4-chloro-6-halo-2-phenylquinazolines 8a and 8b. Conditions: a) NBS, CH3CN, 30 min, 25 ...
Scheme 4: N-Arylation reactions using ortho-, meta-, and para-substituted primary anilines of type 14 followe...
Scheme 5: N-Arylation reactions using 4-chloroquinazoline (16) and 4-chloro-2-methylquinazoline (17) to achie...
Synthetic strategies of phosphonodepsipeptides
- Jiaxi Xu
Beilstein J. Org. Chem. 2021, 17, 461–484, doi:10.3762/bjoc.17.41
- antibiotics [14], antimicrobials [15], antimalarials [16], antitumor agents [17], and medicinal agents [18]. Thus, much attention has been paid to the synthesis of phosphonodepsipeptides. To date, diverse synthetic strategies of phosphonodepsipeptides 1 have been developed. The strategies comprise the
Graphical Abstract
Figure 1: Phosphonopeptides, phosphonodepsipeptides, peptides, and depsipeptides.
Figure 2: The diverse strategies for phosphonodepsipeptide synthesis.
Scheme 1: Synthesis of α-phosphonodepsidipeptides as inhibitors of leucine aminopeptidase.
Figure 3: Structure of 2-hydroxy-2-oxo-3-[(phenoxyacetyl)amino]-1,2-oxaphosphorinane-6-carboxylic acid (16).
Scheme 2: Synthesis of α-phosphonodepsidipeptide 17 as coupling partner for cyclen-containing phosphonodepsip...
Scheme 3: Synthesis of α-phosphonodepsidipeptides containing enantiopure hydroxy ester as VanX inhibitors.
Scheme 4: Synthesis of α-phosphonodepsidipeptides as VanX inhibitors.
Scheme 5: Synthesis of optically active α-phosphonodepsidipeptides as VanX inhibitors.
Scheme 6: The synthesis of phosphonodepsipeptides through a thionyl chloride-catalyzed esterification of N-Cb...
Scheme 7: Synthesis of α-phosphinodipeptidamide as a hapten.
Scheme 8: Synthesis of α-phosphonodepsioctapeptide 41.
Scheme 9: Synthesis of phosphonodepsipeptides via an in situ-generated phosphonochloridate.
Scheme 10: Synthesis of α-phosphonodepsitetrapeptides 58 as inhibitors of the aspartic peptidase pepsin.
Scheme 11: Synthesis of a β-phosphonodepsidipeptide library 64.
Scheme 12: Synthesis of another β-phosphonodepsidipeptide library.
Scheme 13: Synthesis of γ-phosphonodepsidipeptides.
Scheme 14: Synthesis of phosphonodepsipeptides 85 as folylpolyglutamate synthetase inhibitors.
Scheme 15: Synthesis of the γ-phosphonodepsitripeptide 95 as an inhibitor of γ-gutamyl transpeptidase.
Scheme 16: Synthesis of phosphonodepsipeptides as inhibitors and probes of γ-glutamyl transpeptidase.
Scheme 17: Synthesis of phosphonyl depsipeptides 108 via DCC-mediated condensation and oxidation.
Scheme 18: Synthesis of phosphonodepsipeptides 111 with BOP and PyBOP as coupling reagents.
Scheme 19: Synthesis of optically active phosphonodepsipeptides with BOP and PyBOP as coupling reagents.
Scheme 20: Synthesis of phosphonodepsipeptides with BroP and TPyCIU as coupling reagents.
Scheme 21: Synthesis of a phosphonodepsipeptide hapten with BOP as coupling reagent.
Scheme 22: Synthesis of phosphonodepsitripeptide with BOP as coupling reagent.
Scheme 23: Synthesis of norleucine-derived phosphonodepsipeptides 135 and 138.
Scheme 24: Synthesis of norleucine-derived phosphonodepsipeptides 141 and 144.
Scheme 25: Solid-phase synthesis of phosphonodepsipeptides.
Scheme 26: Synthesis of phosphonodepsidipeptides via the Mitsunobu reaction.
Scheme 27: Synthesis of γ-phosphonodepsipeptide via the Mitsunobu reaction.
Scheme 28: Synthesis of phosphonodepsipeptides via a multicomponent condensation reaction.
Scheme 29: Synthesis of phosphonodepsipeptides with a functionalized side-chain via a multicomponent condensat...
Scheme 30: High yielding synthesis of phosphonodepsipeptides via a multicomponent condensation.
Scheme 31: Synthesis of optically active phosphonodepsipeptides via a multicomponent condensation reaction.
Scheme 32: Synthesis of N-phosphoryl phosphonodepsipeptides.
Scheme 33: Synthesis of phosphonodepsipeptides via the alkylation of phosphonic monoesters.
Scheme 34: Synthesis of phosphonodepsipeptides as inhibitors of aspartic protease penicillopepsin.
Scheme 35: Synthesis of phosphonodepsipeptides as prodrugs.
Scheme 36: Synthesis of phosphonodepsithioxopeptides 198.
Scheme 37: Synthesis of phosphonodepsipeptides.
Scheme 38: Synthesis of phosphonodepsipeptides with C-1-hydroxyalkylphosphonic acid.
Scheme 39: Synthesis of phosphonodepsipeptides with C-1-hydroxyalkylphosphonate via the rhodium-catalyzed carb...
Scheme 40: Synthesis of phosphonodepsipeptides with a C-1-hydroxyalkylphosphonate motif via a copper-catalyzed...
Combining enyne metathesis with long-established organic transformations: a powerful strategy for the sustainable synthesis of bioactive molecules
- Valerian Dragutan,
- Ileana Dragutan,
- Albert Demonceau and
- Lionel Delaude
Beilstein J. Org. Chem. 2020, 16, 738–755, doi:10.3762/bjoc.16.68
- reaction for accessing bioactive organic molecules is found in the complex synthesis of manzamine alkaloids. These efficient antitumor agents, originally isolated from several genera of marine sponges, contain a pentacyclic core with a pendant β-carboline moiety. Their total synthesis implies an elaborate
Graphical Abstract
Scheme 1: Intramolecular (A) and intermolecular (B) enyne metathesis reactions.
Scheme 2: Ene–yne and yne–ene mechanisms for intramolecular enyne metathesis reactions.
Scheme 3: Metallacarbene mechanism in intermolecular enyne metathesis.
Scheme 4: The Oguri strategy for accessing artemisinin analogs 1a–c through enyne metathesis.
Scheme 5: Access to the tetracyclic core of nanolobatolide (2) via tandem enyne metathesis followed by an Eu(...
Scheme 6: Synthesis of (−)-amphidinolide E (3) using an intermolecular enyne metathesis as the key step.
Scheme 7: Synthesis of amphidinolide K (4) by an enyne metathesis route.
Scheme 8: Trost synthesis of des-epoxy-amphidinolide N (5) [72].
Scheme 9: Enyne metathesis between the propargylic derivative and the allylic alcohol in the synthesis of the...
Scheme 10: Synthetic route to amphidinolide N (6a).
Scheme 11: Synthesis of the stereoisomeric precursors of amphidinolide V (7a and 7b) through alkyne ring-closi...
Scheme 12: Synthesis of the anthramycin precursor 8 from ʟ-methionine by a tandem enyne metathesis–cross metat...
Scheme 13: Synthesis of (−)‐clavukerin A (9) and (−)‐isoclavukerin A (10) by an enyne metathesis route startin...
Scheme 14: Synthesis of (−)-isoguaiene (11) through an enyne metathesis as the key step.
Scheme 15: Synthesis of erogorgiaene (12) by a tandem enyne metathesis/cross metathesis sequence using the sec...
Scheme 16: Synthesis of (−)-galanthamine (13) from isovanilin by an enyne metathesis.
Scheme 17: Application of enyne metathesis for the synthesis of kempene diterpenes 14a–c.
Scheme 18: Synthesis of the alkaloid (+)-lycoflexine (15) through enyne metathesis.
Scheme 19: Synthesis of the AB subunits of manzamine A (16a) and E (16b) by enyne metathesis.
Scheme 20: Jung's synthesis of rhodexin A (17) by enyne metathesis/cross metathesis reactions.
Scheme 21: Total synthesis of (−)-flueggine A (18) and (+)-virosaine B (19) from Weinreb amide by enyne metath...
Scheme 22: Access to virgidivarine (20) and virgiboidine (21) by an enyne metathesis route.
Scheme 23: Enyne metathesis approach to (−)-zenkequinone B (22).
Scheme 24: Access to C-aryl glycoside 23 by an intermolecular enyne metathesis/Diels–Alder cycloaddition.
Scheme 25: Synthesis of spiro-C-aryl glycoside 24 by a tandem intramolecular enyne metathesis/Diels–Alder reac...
Scheme 26: Pathways to (−)-exiguolide (25) by Trost’s Ru-catalyzed enyne cross-coupling and cross-metathesis [94].
A novel three-component reaction between isocyanides, alcohols or thiols and elemental sulfur: a mild, catalyst-free approach towards O-thiocarbamates and dithiocarbamates
- András György Németh,
- György Miklós Keserű and
- Péter Ábrányi-Balogh
Beilstein J. Org. Chem. 2019, 15, 1523–1533, doi:10.3762/bjoc.15.155
- as enzyme inhibitors [26] or antitumor agents [27]. These species are also used as valuable synthetic intermediates [28] and chemosensors for mercury and silver [29][30]. The general methods for the synthesis of O-thiocarbamates and dithiocarbamates traditionally rely on substitution reactions of the
Graphical Abstract
Scheme 1: Synthetic routes to O-thiocarbamates and dithiocarbamates.
Scheme 2: Substrate scope of isocyanides. aReaction conditions: 1 (1 mmol), S8 (2 mmol), 2a (2mmol), NaH (2 m...
Scheme 3: Substrate scope of alcohols. Reaction conditions: 1a (1 mmol), S8 (2 mmol), 2 (2mmol), NaH (2 mmol)...
Scheme 4: Substrate scope of thiols. Reaction conditions: 1a (1 mmol), S8 (1.2 mmol), 4 (2 mmol), NaOH (2 mmo...
Scheme 5: Scaled-up synthesis for 3a.
Scheme 6: Multicomponent domino synthesis of quinazolinone 7.
Scheme 7: Control experiments.
Scheme 8: Proposed mechanism.
Anomeric sugar boronic acid analogues as potential agents for boron neutron capture therapy
- Daniela Imperio,
- Erika Del Grosso,
- Silvia Fallarini,
- Grazia Lombardi and
- Luigi Panza
Beilstein J. Org. Chem. 2019, 15, 1355–1359, doi:10.3762/bjoc.15.135
- position. The analogues were obtained by hydroboration of proper open-chain terminal alkenes that, after quenching with water, spontaneously afforded cyclic boronic acids with hemiacetal-like structures. Keywords: antitumor agents; boron neutron capture therapy; boronic acid; hydroboration; sugar analogue
Graphical Abstract
Figure 1: Structure of boronic acid analogues (for clarity, sugar numbering has been conserved into the analo...
Figure 2: Structures of boron analogues.
Figure 3: Synthetic strategy.
Scheme 1: Synthesis of 2-deoxy analogue 8.
Figure 4: Postulated transition states for the hydroboration reaction.
Scheme 2: Synthesis of 2,3-dideoxy analogue 11.
Anomeric modification of carbohydrates using the Mitsunobu reaction
- Julia Hain,
- Patrick Rollin,
- Werner Klaffke and
- Thisbe K. Lindhorst
Beilstein J. Org. Chem. 2018, 14, 1619–1636, doi:10.3762/bjoc.14.138
- synthesis of phyllanthostatin antitumor agents, A. B. Smith and colleagues soundly investigated the suitability of the Mitsunobu reaction [29]. They concluded already back in 1986 that “the anomeric hydroxyl group of various pyranose hemiacetals can be esterified with inversion of configuration
Graphical Abstract
Scheme 1: Left: The Mitsunobu reaction is essentially a nucleophilic substitution of alcohols occurring with ...
Scheme 2: Mechanistic considerations on the Mitsunobu reaction with carbohydrate hemiacetals (depicted in sim...
Scheme 3: Anomeric esterification using the Mitsunobu procedure [29].
Scheme 4: Conversion of allyl glucuronate into various 1-O-esterified allyl glucuronates using anomeric Mitsu...
Scheme 5: Synthesis of anomeric glycosyl esters as substrates for Au-catalyzed glycosylation [40].
Scheme 6: Correlation between pKa value of the employed acids (or alcohol) and the favoured anomeric configur...
Scheme 7: Synthesis of the β-mannosyl phosphates for the synthesis of HBP 43 by anomeric phosphorylation acco...
Scheme 8: Synthesis of phenyl glycosides 44 and 45 from unprotected sugars [24].
Scheme 9: Synthesis of azobenzene mannosides 47 and 48 without protecting group chemistry [46].
Scheme 10: Synthesis of various aryl sialosides using Mitsunobu glycosylation [25].
Scheme 11: Mitsunobu synthesis of different jadomycins [54,55]. BOM: benzyloxymethyl.
Scheme 12: Stereoselectivity in the Mitsunobu synthesis of catechol glycosides in the gluco- and manno-series [56]....
Scheme 13: Formation of a 1,2-cis glycoside 80 assisted by steric hindrance of the β-face of the disaccharide ...
Scheme 14: Stereoselective β-D-mannoside synthesis [60].
Scheme 15: TIPS-assisted synthesis of 1,2-cis arabinofuranosides [63]. TIPS: triisopropylsilyl.
Scheme 16: The Mitsunobu reaction with glycals leads to interesting rearrangement products [69].
Scheme 17: Synthesis of disaccharides using mercury(II) bromide as co-activator in the Mitsunobu reaction [75].
Scheme 18: Synthesis of various fructofuranosides according to Mitsunobu and proposed neighbouring group parti...
Scheme 19: The Mitsunobu reaction allows stereoslective acetalization of dihydroartemisinin [77].
Scheme 20: Synthesis of alkyl thioglycosides by Mitsunobu reaction [81].
Scheme 21: Preparation of iminoglycosylphthalimide 115 from 114 [85].
Scheme 22: Mitsunobu reaction as a key step in the total synthesis of aurantoside G [87].
Scheme 23: Utilization of an N–H acid in the Mitsunobu reaction [88].
Scheme 24: Mitsunobu reaction with 1H-tetrazole [89].
Scheme 25: Formation of a rebeccamycin analogue using the Mitsunobu reaction [101].
Scheme 26: Synthesis of carbohydrates with an alkoxyamine bond [114].
Scheme 27: Synthesis of glycosyl fluorides and glycosyl azides according to Mitsunobu [118,119].
Scheme 28: Anomeric oxidation under Mitsunobu conditions [122].
Glycosylation reactions mediated by hypervalent iodine: application to the synthesis of nucleosides and carbohydrates
- Yuichi Yoshimura,
- Hideaki Wakamatsu,
- Yoshihiro Natori,
- Yukako Saito and
- Noriaki Minakawa
Beilstein J. Org. Chem. 2018, 14, 1595–1618, doi:10.3762/bjoc.14.137
- promising candidates for novel antitumor agents. Thus, we designed a novel 2’-substituted 4’-thiocytidine, 4’-thioDMDC (3), as our target molecule for potential antitumor agents [27][28] (Figure 1). At the time we started our project, there had been no reports regarding the synthesis of even 2-substituted 4
Graphical Abstract
Figure 1: Design of potential antineoplastic nucleosides.
Scheme 1: Synthesis of 4’-thioDMDC.
Scheme 2: Synthesis of 4’-thioribonucleosides by Minakawa and Matsuda.
Scheme 3: Synthesis of 4’-thioribonucleosides by Yoshimura.
Figure 2: Concept of the Pummerer-type glycosylation and hypervalent iodine-mediated glycosylation.
Scheme 4: Oxidative glycosylation of 4-thioribose mediated by hypervalent iodine.
Figure 3: Speculated mechanism of oxidative glycosylation mediated by hypervalent iodine.
Scheme 5: Synthesis of purine 4’-thioribonucleosides using hypervalent iodine-mediated glycosylation.
Scheme 6: Unexpected glycosylation of a thietanose derivative.
Scheme 7: Speculated mechanism of the ring expansion of a thietanose derivative.
Scheme 8: Synthesis of thietanonucleosides using the Pummerer-type glycosylation.
Scheme 9: First synthesis of 4’-selenonucleosides.
Scheme 10: The Pummerer-type glycosylation of 4-selenoxide 74.
Scheme 11: Synthesis of purine 4’-selenonucleosides using hypervalent iodine-mediated glycosylation.
Figure 4: Concept of the oxidative coupling reaction applicable to the synthesis of carbocyclic nucleosides.
Scheme 12: Oxidative coupling reaction mediated by hypervalent iodine.
Scheme 13: Synthesis of cyclohexenyl nucleosides using an oxidative coupling reaction.
Figure 5: Concept of the oxidative coupling reaction of glycal derivatives.
Scheme 14: Oxidative coupling reaction of silylated uracil and DHP using hypervalent iodine.
Scheme 15: Proposed mechanism of the oxidative coupling reaction mediated by hypervalent iodine.
Figure 6: Synthesis of 2’,3’-unsaturated nucleosides using hypervalent iodine and a co-catalyst.
Scheme 16: Synthesis of dihydropyranonucleoside.
Scheme 17: Synthesis of acetoxyacetals using hypervalent iodine and addition of silylated base.
Scheme 18: One-pot fragmentation-nucleophilic additions mediated by hypervalent iodine.
Figure 7: The reaction of thioglycoside with hypervalent iodine in the presence of Lewis acids.
Scheme 19: Synthesis of disaccharides employing thioglycosides under an oxidative coupling reaction mediated b...
Scheme 20: Synthesis of disaccharides using disarmed thioglycosides by hypervalent iodine-mediated glycosylati...
Scheme 21: Glycosylation using aryl(trifluoroethyl)iodium triflimide.
Figure 8: Expected mechanism of hypervalent iodine-mediated glycosylation with glycals.
Scheme 22: Synthesis of oligosaccharides by hypervalent iodine-mediated glycosylation with glycals.
Scheme 23: Synthesis of 2-deoxy amino acid glycosides.
Figure 9: Rationale for the intramolecular migration of the amino acid unit.
An overview of recent advances in duplex DNA recognition by small molecules
- Sayantan Bhaduri,
- Nihar Ranjan and
- Dev P. Arya
Beilstein J. Org. Chem. 2018, 14, 1051–1086, doi:10.3762/bjoc.14.93
Graphical Abstract
Figure 1: A figure showing the hydrogen bonding patterns observed in (a) duplex (b) triplex and (c) quadruple...
Figure 2: (a) Portions of MATα1–MATα2 are shown contacting the minor groove of the DNA substrate. Key arginin...
Figure 3: Chemical structures of naturally occurring and synthetic hybrid minor groove binders.
Figure 4: Synthetic structural analogs of distamycin A by replacing one or more pyrrole rings with other hete...
Figure 5: Pictorial representation of the binding model of pyrrole–imidazole (Py/Im) polyamides based on the ...
Figure 6: Chemical structures of synthetic “hairpin” pyrrole–imidazole (Py/Im) conjugates.
Figure 7: (a) Minor groove complex formation between DNA duplex and 8-ring cyclic Py/Im polyamide (conjugate ...
Figure 8: Telomere-targeting tandem hairpin Py/Im polyamides 23 and 24 capable of recognizing >10 base pairs; ...
Figure 9: Representative examples of recently developed DNA minor groove binders.
Figure 10: Chemical structures of bisbenzamidazoles Hoechst 33258 and 33342 and their synthetic structural ana...
Figure 11: Chemical structures of bisamidines such as diminazene, DAPI, pentamidine and their synthetic struct...
Figure 12: Representative examples of recently developed bisamidine derivatives.
Figure 13: Chemical structures of chromomycin, mithramycin and their synthetic structural analogs 91 and 92.
Figure 14: Chemical structures of well-known naturally occurring DNA binding intercalators.
Figure 15: Naturally occurring indolocarbazole rebeccamycin and its synthetic analogs.
Figure 16: Representative examples of naturally occurring and synthetic derivatives of DNA intercalating agent...
Figure 17: Several recent synthetic varieties of DNA intercalators.
Figure 18: Aminoglycoside (neomycin)–Hoechst 33258/intercalator conjugates.
Figure 19: Chemical structures of triazole linked neomycin dimers and neomycin–bisbenzimidazole conjugates.
Figure 20: Representative examples of naturally occurring and synthetic analogs of DNA binding alkylating agen...
Figure 21: Chemical structures of naturally occurring and synthetic analogs of pyrrolobenzodiazepines.
Synthesis and biological evaluation of RGD and isoDGR peptidomimetic-α-amanitin conjugates for tumor-targeting
- Lizeth Bodero,
- Paula López Rivas,
- Barbara Korsak,
- Torsten Hechler,
- Andreas Pahl,
- Christoph Müller,
- Daniela Arosio,
- Luca Pignataro,
- Cesare Gennari and
- Umberto Piarulli
Beilstein J. Org. Chem. 2018, 14, 407–415, doi:10.3762/bjoc.14.29
- , αVβ6, and α5β1. These data indicate that in this case the cyclo[DKP-isoDGR]-α-amanitin conjugates are possibly internalized by a process mediated by integrins different from αVβ3 (e.g., αVβ5). Keywords: antitumor agents; cancer; drug delivery; integrins; peptidomimetics; Introduction α-Amanitin is a
Graphical Abstract
Figure 1: α-Amanitin.
Figure 2: Structure of the ligands cyclo[DKP-RGD] (1), NH2CH2-cyclo[DKP-RGD] (2), cyclo[DKP-isoDGR] (3), NH2CH...
Figure 3: Structure of the α-amanitin conjugates: cyclo[DKP-RGD]-uncleavable-α-amanitin (7), cyclo[DKP-isoDGR...
Scheme 1: Synthesis of α-amanitin-cyclo[DKP-RGD] and α-amanitin-cyclo[DKP-isoDGR] conjugates 7–10. Reagents a...
Scheme 2: Synthesis of cyclo[DKP-isoDGR]-PEG-4-Val-Ala-α-amanitin conjugate 11. Reagents and conditions: a) 4...
Photocatalytic formation of carbon–sulfur bonds
- Alexander Wimmer and
- Burkhard König
Beilstein J. Org. Chem. 2018, 14, 54–83, doi:10.3762/bjoc.14.4
- groups decreased the yield of the reaction. A series of 2-alkylsubstituted benzothiophenes were prepared and the method was applied for the synthesis of antitumor agents. In the same year, the group of Singh published two similar, but metal-free procedures. In the first report a new photocatalyzed
Graphical Abstract
Scheme 1: General overview over the sulfur-based substrates and reactive intermediates that are discussed in ...
Scheme 2: Photoredox-catalyzed radical thiol–ene reaction, applying [Ru(bpz)3](PF6)2 as photocatalyst.
Scheme 3: Photoredox-catalyzed thiol–ene reaction of aliphatic thiols with alkenes enabled by aniline derivat...
Scheme 4: Photoredox-catalyzed radical thiol–ene reaction for the postfunctionalization of polymers (a) and n...
Scheme 5: Photoredox-catalyzed thiol–ene reaction enabled by bromotrichloromethane as redox additive.
Scheme 6: Photoredox-catalyzed preparation of β-ketosulfoxides with Eosin Y as organic dye as photoredox cata...
Scheme 7: Greaney’s photocatalytic radical thiol–ene reaction, applying TiO2 nanoparticles as photocatalyst.
Scheme 8: Fadeyi’s photocatalytic radical thiol–ene reaction, applying Bi2O3 as photocatalyst.
Scheme 9: Ananikov’s photocatalytic radical thiol-yne reaction, applying Eosin Y as photocatalyst.
Scheme 10: Organocatalytic visible-light photoinitiated thiol–ene coupling, applying phenylglyoxylic acid as o...
Scheme 11: Xia’s photoredox-catalyzed synthesis of 2,3-disubstituted benzothiophenes, applying 9-mesityl-10-me...
Scheme 12: Wang’s metal-free photoredox-catalyzed radical thiol–ene reaction, applying 9-mesityl-10-methylacri...
Scheme 13: Visible-light benzophenone-catalyzed metal- and oxidant-free radical thiol–ene reaction.
Scheme 14: Visible-light catalyzed C-3 sulfenylation of indole derivatives using Rose Bengal as organic dye.
Scheme 15: Photocatalyzed radical thiol–ene reaction and subsequent aerobic sulfide-oxidation with Rose Bengal...
Scheme 16: Photoredox-catalyzed synthesis of diaryl sulfides.
Scheme 17: Photocatalytic cross-coupling of aryl thiols with aryl diazonium salts, using Eosin Y as photoredox...
Scheme 18: Photocatalyzed cross-coupling of aryl diazonium salts with cysteines in batch and in a microphotore...
Scheme 19: Fu’s [Ir]-catalyzed photoredox arylation of aryl thiols with aryl halides.
Scheme 20: Fu’s photoredox-catalyzed difluoromethylation of aryl thiols.
Scheme 21: C–S cross-coupling of thiols with aryl iodides via [Ir]-photoredox and [Ni]-dual-catalysis.
Scheme 22: C–S cross-coupling of thiols with aryl bromides, applying 3,7-bis-(biphenyl-4-yl)-10-(1-naphthyl)ph...
Scheme 23: Collin’s photochemical dual-catalytic cross-coupling of thiols with bromoalkynes.
Scheme 24: Visible-light-promoted C–S cross-coupling via intermolecular electron donor–acceptor complex format...
Scheme 25: Li’s visible-light photoredox-catalyzed thiocyanation of indole derivatives with Rose Bengal as pho...
Scheme 26: Hajra’s visible-light photoredox-catalyzed thiocyanation of imidazoheterocycles with Eosin Y as pho...
Scheme 27: Wang’s photoredox-catalyzed thiocyanation reaction of indoles, applying heterogeneous TiO2/MoS2 nan...
Scheme 28: Yadav’s photoredox-catalyzed α-C(sp3)–H thiocyanation reaction for tertiary amines, applying Eosin ...
Scheme 29: Yadav’s photoredox-catalyzed synthesis of 5-aryl-2-imino-1,3-oxathiolanes.
Scheme 30: Yadav’s photoredox-catalyzed synthesis of 1,3-oxathiolane-2-thiones.
Scheme 31: Li’s photoredox catalysis for the preparation of 2-substituted benzothiazoles, applying [Ru(bpy)3](...
Scheme 32: Lei’s external oxidant-free synthesis of 2-substituted benzothiazoles by merging photoredox and tra...
Scheme 33: Metal-free photocatalyzed synthesis of 2-aminobenzothiazoles, applying Eosin Y as photocatalyst.
Scheme 34: Metal-free photocatalyzed synthesis of 1,3,4-thiadiazoles, using Eosin Y as photocatalyst.
Scheme 35: Visible-light photoredox-catalyzed preparation of benzothiophenes with Eosin Y.
Scheme 36: Visible-light-induced KOH/DMSO superbase-promoted preparation of benzothiophenes.
Scheme 37: Jacobi von Wangelin’s photocatalytic approach for the synthesis of aryl sulfides, applying Eosin Y ...
Scheme 38: Visible-light photosensitized α-C(sp3)–H thiolation of aliphatic ethers.
Scheme 39: Visible-light photocatalyzed cross-coupling of alkyl and aryl thiosulfates with aryl diazonium salt...
Scheme 40: Visible-light photocatalyzed, controllable sulfenylation and sulfoxidation with organic thiosulfate...
Scheme 41: Rastogi’s photoredox-catalyzed methylsulfoxidation of aryl diazonium salts, using [Ru(bpy)3]Cl2 as ...
Scheme 42: a) Visible-light metal-free Eosin Y-catalyzed procedure for the preparation of vinyl sulfones from ...
Scheme 43: Visible-light photocatalyzed cross-coupling of sodium sulfinates with secondary enamides.
Scheme 44: Wang’s photocatalyzed oxidative cyclization of phenyl propiolates with sulfinic acids, applying Eos...
Scheme 45: Lei’s sacrificial oxidant-free synthesis of allyl sulfones by merging photoredox and transition met...
Scheme 46: Photocatalyzed Markovnikov-selective radical/radical cross-coupling of aryl sulfinic acids and term...
Scheme 47: Visible-light Eosin Y induced cross-coupling of aryl sulfinic acids and styrene derivatives, afford...
Scheme 48: Photoredox-catalyzed bicyclization of 1,7-enynes with sulfinic acids, applying Eosin Y as photocata...
Scheme 49: Visible-light-accelerated C–H-sulfinylation of arenes and heteroarenes.
Scheme 50: Visible-light photoredox-catalyzed β-selenosulfonylation of electron-rich olefins, applying [Ru(bpy)...
Scheme 51: Photocatalyzed preparation of β-chlorosulfones from the respective olefins and p-toluenesulfonyl ch...
Scheme 52: a) Photocatalyzed preparation of β-amidovinyl sulfones from sulfonyl chlorides. b) Preparation of β...
Scheme 53: Visible-light photocatalyzed sulfonylation of aliphatic tertiary amines, applying [Ru(bpy)3](PF6)2 ...
Scheme 54: Reiser’s visible-light photoredox-catalyzed preparation of β-hydroxysulfones from sulfonyl chloride...
Scheme 55: a) Sun’s visible-light-catalyzed approach for the preparation of isoquinolinonediones, applying [fac...
Scheme 56: Visible-light photocatalyzed sulfonylation/cyclization of vinyl azides, applying [Ru(bpy)3]Cl2 as p...
Scheme 57: Visible-light photocatalyzed procedure for the formation of β-ketosulfones from aryl sulfonyl chlor...
Scheme 58: Zheng’s method for the sulfenylation of indole derivatives, applying sulfonyl chlorides via visible...
Scheme 59: Cai’s visible-light induced synthesis of β-ketosulfones from sulfonyl hydrazines and alkynes.
Scheme 60: Photoredox-catalyzed approach for the preparation of vinyl sulfones from sulfonyl hydrazines and ci...
Scheme 61: Jacobi von Wangelin’s visible-light photocatalyzed chlorosulfonylation of anilines.
Scheme 62: Three-component photoredox-catalyzed synthesis of N-amino sulfonamides, applying PDI as organic dye....
Scheme 63: Visible-light induced preparation of complex sulfones from oximes, silyl enol ethers and SO2.
Acid-catalyzed ring-opening reactions of a cyclopropanated 3-aza-2-oxabicyclo[2.2.1]hept-5-ene with alcohols
- Katrina Tait,
- Alysia Horvath,
- Nicolas Blanchard and
- William Tam
Beilstein J. Org. Chem. 2017, 13, 2888–2894, doi:10.3762/bjoc.13.281
- the synthesis of 2’,3’-methano carbocyclic nucleosides via compound 24 (Scheme 5) [17]. Carbocyclic nucleosides are important synthetic targets because of their use as antiviral and antitumor agents [17]. Replacing the oxygen unit in the parent furanose ring with a methylene unit helps to stabilize
Graphical Abstract
Scheme 1: General reaction pathways for 3-aza-2-oxabicyclic alkenes.
Scheme 2: Various reactions involving modification of the alkene component of 3-aza-2-oxabicyclic alkenes.
Scheme 3: Various reactions involving cleavage of the C–O bond of 3-aza-2-oxabicyclic alkenes.
Scheme 4: Ring-opening reactions of cyclopropanated 3-aza-2-oxabicyclic alkenes.
Scheme 5: Different possible ring-opening pathways of cyclopropanated 3-aza-2-oxabicyclic alkenes.
Scheme 6: Possible mechanisms for the nucleophilic ring-opening of cyclopropanated 3-aza-2-oxabicyclic alkene ...
A novel synthetic approach to hydroimidazo[1,5-b]pyridazines by the recyclization of itaconimides and HPLC–HRMS monitoring of the reaction pathway
- Dmitry Yu. Vandyshev,
- Khidmet S. Shikhaliev,
- Andrey Yu. Potapov,
- Michael Yu. Krysin,
- Fedor I. Zubkov and
- Lyudmila V. Sapronova
Beilstein J. Org. Chem. 2017, 13, 2561–2568, doi:10.3762/bjoc.13.252
- ], antitumor agents [9], and are stimulators of guanylate cyclase [10], whereas imidazo[1,5-c]pyrimidines demonstrate anti-infectious effects in the treatment of brucellosis [11], etc. However, the chemistry, medicinal chemistry and pharmacology of imidazo[1,5-b]pyridazines, with the imidazole ring connected
Graphical Abstract
Scheme 1: Intramolecular cyclization of 3-(aminomethyl)pyridazines and related compounds (route A). Condition...
Scheme 2: Heterocyclization of 1-aminoimidazoles with 1,3-dicarbonyl or α,β-unsaturated carbonyl compounds (r...
Scheme 3: Heterocyclization of 1-aminoimidazoles with structural transformation of dielectrophilic reagents (...
Scheme 4: Recyclization of N-arylitaconimides 1 with 1,2-diaminobenzimidazole (2).
Scheme 5: Possible synthetic routes of the interaction of itaconimides 1 with diaminoimidazole 4.
Scheme 6: 1H,13C-HMBC correlations: the most significant correlations for imidazopyridazine 9d and possible f...
Synthesis of spiro[isoindole-1,5’-isoxazolidin]-3(2H)-ones as potential inhibitors of the MDM2-p53 interaction
- Salvatore V. Giofrè,
- Santa Cirmi,
- Raffaella Mancuso,
- Francesco Nicolò,
- Giuseppe Lanza,
- Laura Legnani,
- Agata Campisi,
- Maria A. Chiacchio,
- Michele Navarra,
- Bartolo Gabriele and
- Roberto Romeo
Beilstein J. Org. Chem. 2016, 12, 2793–2807, doi:10.3762/bjoc.12.278
- be linked to the inhibition of the protein–protein p53-MDM2 interaction. Docking measurements support the biological data. Keywords: antitumor agents; DFT studies; 1,3-dipolar cycloaddition; docking studies; spiro-compounds; Introduction The p53 tumor suppressor protein is a transcriptional factor
Graphical Abstract
Figure 1: Some relevant MDM2-p53 interaction inhibitors.
Figure 2: Retrosynthetic route to spiro[isoindole-1,5-isoxazolidin]-3(2H)-ones 3.
Scheme 1: Synthesis of compounds 2.
Scheme 2: Synthesis of 6a–f by 1,3-dipolar cycloaddition.
Figure 3: Selected NOESY observed for compounds 6a and 7a.
Figure 4: ORTEP drawing of the X-ray crystal structure of 7a showing the model atomic numbering scheme (C10 a...
Scheme 3: Reaction pathway.
Figure 5: Three-dimensional plots of TSs of reaction of dipolarophiles (Z)-8 and (E)-8 with nitrone 4. The la...
Figure 6: Free energy profiles for the cycloaddition reaction of the two isomers Z (A) or E (B) of dipolaroph...
Figure 7: Compound 6e reduces cancer cell proliferation. Treatment of SH-SY5Y, HT-29 and HepG2 cells with 6e ...
Figure 8: Cytotoxic effect of 6e. The cytotoxic activity of 6e was assessed in terms of both LDH release (a) ...
Figure 9: 6e modulate the levels of p53 in SH-SY5Y cells. (a) The SH-SY5Y cells were treated for 24 h with th...
Figure 10: (A) Representative Western Blots and (B) semiquantitative analyses of p53, MDM2, p21 expression lev...
Figure 11: (A) Representative Western Blots and (B) densitometric analysis of caspase-3 and PARP cleavage in t...
Figure 12: Compounds 6a (green) and 6c (blue) docked into MDM2 structure (PDB-ID: 3LBL) superimposed on the ke...
Figure 13: A) Compounds 6e (green) docked into MDM2 structure (PDB-ID: 3LBL); His96 and p53 residue (yellow st...
Rapid regio- and multi-coupling reactivity of 2,3-dibromobenzofurans with atom-economic triarylbismuths under palladium catalysis
- Maddali L. N. Rao,
- Jalindar B. Talode and
- Venneti N. Murty
Beilstein J. Org. Chem. 2016, 12, 2065–2076, doi:10.3762/bjoc.12.195
- , 2,3-disubstituted benzofurans are biologically important (Figure 1a–d) and a few reports about their isolation and synthetic methods are available [17][18][19]. Substituted benzofurans serve as antitumor agents [20], protein tyrosine phosphatase-1B inhibitors [21], antimycobacterial agents [22] and as
Graphical Abstract
Figure 1: Important benzofuran skeletons.
Scheme 1: Bis- and tris-couplings.
Figure 2: X-ray structure of bis-coupling product 3.1 (CCDC-1425338) [43].
Rearrangements of organic peroxides and related processes
- Ivan A. Yaremenko,
- Vera A. Vil’,
- Dmitry V. Demchuk and
- Alexander O. Terent’ev
Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162
Graphical Abstract
Figure 1: The named transformations considered in this review.
Scheme 1: The Baeyer–Villiger oxidation.
Scheme 2: The general mechanism of the peracid-promoted Baeyer–Villiger oxidation.
Scheme 3: General mechanism of the Lewis acid-catalyzed Baeyer–Villiger rearrangement.
Scheme 4: The theoretically studied mechanism of the BV oxidation reaction promoted by H2O2 and the Lewis aci...
Scheme 5: Proton movements in the transition states of the Baeyer–Villiger oxidation.
Scheme 6: The dependence of the course of the Baeyer–Villiger oxidation on the type of O–O-bond cleavage in t...
Scheme 7: The acid-catalyzed Baeyer–Villiger oxidation of cyclic epoxy ketones 22.
Scheme 8: Oxidation of isophorone oxide 29.
Scheme 9: Synthesis of acyl phosphate 32 from acyl phosphonate 31.
Scheme 10: Synthesis of aflatoxin B2 (36).
Scheme 11: The Baeyer–Villiger rearrangement of ketones 37 to lactones 38.
Scheme 12: Synthesis of 3,4-dimethoxybenzoic acid (40) via Baeyer–Villiger oxidation.
Scheme 13: Oxone transforms α,β-unsaturated ketones 43 into vinyl acetates 44.
Scheme 14: The Baeyer–Villiger oxidation of ketones 45 using diaryl diselenide and hydrogen peroxide.
Scheme 15: Baeyer–Villiger oxidation of (E)-2-methylenecyclobutanones.
Scheme 16: Oxidation of β-ionone (56) by H2O2/(BnSe)2 with formation of (E)-2-(2,6,6-trimethylcyclohex-1-en-1-...
Scheme 17: The mechanism of oxidation of ketones 58a–f by hydrogen peroxide in the presence of arsonated polys...
Scheme 18: Oxidation of ketone (58b) by H2O2 to 6-methylcaprolactone (59b) catalyzed by Pt complex 66·BF4.
Scheme 19: Oxidation of ketones 67 with H2O2 in the presence of [(dppb}Pt(µ-OH)]22+.
Scheme 20: The mechanism of oxidation of ketones 67 in the presence of [(dppb}Pt(µ-OH)]22+ and H2O2.
Scheme 21: Oxidation of benzaldehydes 69 in the presence of the H2O2/MeReO3 system.
Scheme 22: Oxidation of acetophenones 72 in the presence of the H2O2/MeReO3 system.
Scheme 23: Baeyer–Villiger oxidation of 2-adamantanone (45c) in the presence of Sn-containing mesoporous silic...
Scheme 24: Aerobic Baeyer–Villiger oxidation of ketones 76 using metal-free carbon.
Scheme 25: A regioselective Baeyer-Villiger oxidation of functionalized cyclohexenones 78 into a dihydrooxepin...
Scheme 26: The oxidation of aldehydes and ketones 80 by H2O2 catalyzed by Co4HP2Mo15V3O62.
Scheme 27: The cleavage of ketones 82 with hydrogen peroxide in alkaline solution.
Scheme 28: Oxidation of ketones 85 to esters 86 with H2O2–urea in the presence of KHCO3.
Scheme 29: Mechanism of the asymmetric oxidation of cyclopentane-1,2-dione 87a with the Ti(OiPr)4/(+)DET/t-BuO...
Scheme 30: The oxidation of cis-4-tert-butyl-2-fluorocyclohexanone (93) with m-chloroperbenzoic acid.
Scheme 31: The mechanism of the asymmetric oxidation of 3-substituted cyclobutanone 96a in the presence of chi...
Scheme 32: Enantioselective Baeyer–Villiger oxidation of cyclic ketones 98.
Scheme 33: Regio- and enantioselective Baeyer–Villiger oxidation of cyclic ketones 101.
Scheme 34: The proposed mechanism of the Baeyer–Villiger oxidation of acetal 105f.
Scheme 35: Synthesis of hydroxy-10H-acridin-9-one 117 from tetramethoxyanthracene 114.
Scheme 36: The Baeyer–Villiger oxidation of the fully substituted pyrrole 120.
Scheme 37: The Criegee rearrangement.
Scheme 38: The mechanism of the Criegee reaction of a peracid with a tertiary alcohol 122.
Scheme 39: Criegee rearrangement of decaline ethylperoxoate 127 into ketal 128.
Scheme 40: The ionic cleavage of 2-methoxy-2-propyl perester 129.
Scheme 41: The Criegee rearrangement of α-methoxy hydroperoxide 136.
Scheme 42: Synthesis of enol esters and acetals via the Criegee rearrangement.
Scheme 43: Proposed mechanism of the transformation of 1-hydroperoxy-2-oxabicycloalkanones 147a–d.
Scheme 44: Transformation of 3-hydroxy-1,2-dioxolanes 151 into diketone derivatives 152.
Scheme 45: Criegee rearrangement of peroxide 153 with the mono-, di-, and tri-O-insertion.
Scheme 46: The sequential Criegee rearrangements of adamantanes 157a,b.
Scheme 47: Synthesis of diaryl carbonates 160a–d from triarylmethanols 159a–d through successive oxygen insert...
Scheme 48: The synthesis of sesquiterpenes 162 from ketone 161 with a Criegee rearrangement as one key step.
Scheme 49: Synthesis of trans-hydrindan derivatives 164, 165.
Scheme 50: The Hock rearrangement.
Scheme 51: The general scheme of the cumene process.
Scheme 52: The Hock rearrangement of aliphatic hydroperoxides.
Scheme 53: The mechanism of solvolysis of brosylates 174a–c and spiro cyclopropyl carbinols 175a–c in THF/H2O2....
Scheme 54: The fragmentation mechanism of hydroperoxy acetals 178 to esters 179.
Scheme 55: The acid-catalyzed rearrangement of phenylcyclopentyl hydroperoxide 181.
Scheme 56: The peroxidation of tertiary alcohols in the presence of a catalytic amount of acid.
Scheme 57: The acid-catalyzed reaction of bicyclic secondary alcohols 192 with hydrogen peroxide.
Scheme 58: The photooxidation of 5,6-disubstituted 3,4-dihydro-2H-pyrans 196.
Scheme 59: The oxidation of tertiary alcohols 200a–g, 203a,b, and 206.
Scheme 60: Transformation of functional peroxide 209 leading to 2,3-disubstitued furans 210 in one step.
Scheme 61: The synthesis of carbazoles 213 via peroxide rearrangement.
Scheme 62: The construction of C–N bonds using the Hock rearrangement.
Scheme 63: The synthesis of moiety 218 from 217 which is a structural motif in the antitumor–antibiotic of CC-...
Scheme 64: The in vivo oxidation steps of cholesterol (219) by singlet oxygen.
Scheme 65: The proposed mechanism of the rearrangement of cholesterol-5α-OOH 220.
Scheme 66: Photochemical route to artemisinin via Hock rearrangement of 223.
Scheme 67: The Kornblum–DeLaMare rearrangement.
Scheme 68: Kornblum–DeLaMare transformation of 1-phenylethyl tert-butyl peroxide (225).
Scheme 69: The synthesis 4-hydroxyenones 230 from peroxide 229.
Scheme 70: The Kornblum–DeLaMare rearrangement of peroxide 232.
Scheme 71: The reduction of peroxide 234.
Scheme 72: The Kornblum–DeLaMare rearrangement of endoperoxide 236.
Scheme 73: The rearrangement of peroxide 238 under Kornblum–DeLaMare conditions.
Scheme 74: The proposed mechanism of rearrangement of peroxide 238.
Scheme 75: The Kornblum–DeLaMare rearrangement of peroxides 242a,b.
Scheme 76: The base-catalyzed rearrangements of bicyclic endoperoxides having electron-withdrawing substituent...
Scheme 77: The base-catalyzed rearrangements of bicyclic endoperoxides 249a,b having electron-donating substit...
Scheme 78: The base-catalyzed rearrangements of bridge-head substituted bicyclic endoperoxides 251a,b.
Scheme 79: The Kornblum–DeLaMare rearrangement of hydroperoxide 253.
Scheme 80: Synthesis of β-hydroxy hydroperoxide 254 from endoperoxide 253.
Scheme 81: The amine-catalyzed rearrangement of bicyclic endoperoxide 263.
Scheme 82: The base-catalyzed rearrangement of meso-endoperoxide 268 into 269.
Scheme 83: The photooxidation of 271 and subsequent Kornblum–DeLaMare reaction.
Scheme 84: The Kornblum–DeLaMare rearrangement as one step in the oxidation reaction of enamines.
Scheme 85: The Kornblum–DeLaMare rearrangement of 3,5-dihydro-1,2-dioxenes 284, 1,2-dioxanes 286, and tert-but...
Scheme 86: The Kornblum–DeLaMare rearrangement of epoxy dioxanes 290a–d.
Scheme 87: Rearrangement of prostaglandin H2 292.
Scheme 88: The synthesis of epicoccin G (297).
Scheme 89: The Kornblum–DeLaMare rearrangement used in the synthesis of phomactin A.
Scheme 90: The Kornblum–DeLaMare rearrangement in the synthesis of 3H-quinazolin-4-one 303.
Scheme 91: The Kornblum–DeLaMare rearrangement in the synthesis of dolabriferol (308).
Scheme 92: Sequential transformation of 3-substituted 2-pyridones 309 into 3-hydroxypyridine-2,6-diones 311 in...
Scheme 93: The Kornblum–DeLaMare rearrangement of peroxide 312 into hydroxy enone 313.
Scheme 94: The Kornblum–DeLaMare rearrangement in the synthesis of polyfunctionalized carbonyl compounds 317.
Scheme 95: The Kornblum–DeLaMare rearrangement in the synthesis of (Z)-β-perfluoroalkylenaminones 320.
Scheme 96: The Kornblum–DeLaMare rearrangement in the synthesis of γ-ketoester 322.
Scheme 97: The Kornblum–DeLaMare rearrangement in the synthesis of diterpenoids 326 and 328.
Scheme 98: The synthesis of natural products hainanolidol (331) and harringtonolide (332) from peroxide 329.
Scheme 99: The synthesis of trans-fused butyrolactones 339 and 340.
Scheme 100: The synthesis of leucosceptroid C (343) and leucosceptroid P (344) via the Kornblum–DeLaMare rearra...
Scheme 101: The Dakin oxidation of arylaldehydes or acetophenones.
Scheme 102: The mechanism of the Dakin oxidation.
Scheme 103: A solvent-free Dakin reaction of aromatic aldehydes 356.
Scheme 104: The organocatalytic Dakin oxidation of electron-rich arylaldehydes 358.
Scheme 105: The Dakin oxidation of electron-rich arylaldehydes 361.
Scheme 106: The Dakin oxidation of arylaldehydes 358 in water extract of banana (WEB).
Scheme 107: A one-pot approach towards indolo[2,1-b]quinazolines 364 from indole-3-carbaldehydes 363 through th...
Scheme 108: The synthesis of phenols 367a–c from benzaldehydes 366a-c via acid-catalyzed Dakin oxidation.
Scheme 109: Possible transformation paths of the highly polarized boric acid coordinated H2O2–aldehyde adduct 3...
Scheme 110: The Elbs oxidation of phenols 375 to hydroquinones.
Scheme 111: The mechanism of the Elbs persulfate oxidation of phenols 375 affording p-hydroquinones 376.
Scheme 112: Oxidation of 2-pyridones 380 under Elbs persulfate oxidation conditions.
Scheme 113: Synthesis of 3-hydroxy-4-pyridone (384) via an Elbs oxidation of 4-pyridone (382).
Scheme 114: The Schenck rearrangement.
Scheme 115: The Smith rearrangement.
Scheme 116: Three main pathways of the Schenck rearrangement.
Scheme 117: The isomerization of hydroperoxides 388 and 389.
Scheme 118: Trapping of dioxacyclopentyl radical 392 by oxygen.
Scheme 119: The hypothetical mechanism of the Schenck rearrangement of peroxide 394.
Scheme 120: The autoxidation of oleic acid (397) with the use of labeled isotope 18O2.
Scheme 121: The rearrangement of 18O-labeled hydroperoxide 400 under an atmosphere of 16O2.
Scheme 122: The rearrangement of the oleate-derived allylic hydroperoxides (S)-421 and (R)-425.
Scheme 123: Mechanisms of Schenck and Smith rearrangements.
Scheme 124: The rearrangement and cyclization of 433.
Scheme 125: The Wieland rearrangement.
Scheme 126: The rearrangement of bis(triphenylsilyl) 439 or bis(triphenylgermyl) 441 peroxides.
Scheme 127: The oxidative transformation of cyclic ketones.
Scheme 128: The hydroxylation of cyclohexene (447) in the presence of tungstic acid.
Scheme 129: The oxidation of cyclohexene (447) under the action of hydrogen peroxide.
Scheme 130: The reaction of butenylacetylacetone 455 with hydrogen peroxide.
Scheme 131: The oxidation of bridged 1,2,4,5-tetraoxanes.
Scheme 132: The proposed mechanism for the oxidation of bridged 1,2,4,5-tetraoxanes.
Scheme 133: The rearrangement of ozonides.
Scheme 134: The acid-catalyzed oxidative rearrangement of malondialdehydes 462 under the action of H2O2.
Scheme 135: Pathways of the Lewis acid-catalyzed cleavage of dialkyl peroxides 465 and ozonides 466.
Scheme 136: The mechanism of the transformation of (tert-butyldioxy)cyclohexanedienones 472.
Scheme 137: The synthesis of Vitamin K3 from 472a.
Scheme 138: Proposed mechanism for the transformation of 478d into silylated endoperoxide 479d.
Scheme 139: The rearrangement of hydroperoxide 485 to form diketone 486.
Scheme 140: The base-catalyzed rearrangement of cyclic peroxides 488a–g.
Scheme 141: Synthesis of chiral epoxides and aldols from peroxy hemiketals 491.
Scheme 142: The multistep transformation of (R)-carvone (494) to endoperoxides 496a–e.
Scheme 143: The decomposition of anthracene endoperoxide 499.
Scheme 144: Synthesis of esters 503 from aldehydes 501 via rearrangement of peroxides 502.
Scheme 145: Two possible paths for the base-promoted decomposition of α-azidoperoxides 502.
Scheme 146: The Story decomposition of cyclic diperoxide 506a.
Scheme 147: The Story decomposition of cyclic triperoxide 506b.
Scheme 148: The thermal rearrangement of endoperoxides A into diepoxides B.
Scheme 149: The transformation of peroxide 510 in the synthesis of stemolide (511).
Scheme 150: The possible mechanism of the rearrangement of endoperoxide 261g.
Scheme 151: The photooxidation of indene 517.
Scheme 152: The isomerization of ascaridole (523).
Scheme 153: The isomerization of peroxide 525.
Scheme 154: The thermal transformation of endoperoxide 355.
Scheme 155: The photooxidation of cyclopentadiene (529) at a temperature higher than 0 °C.
Scheme 156: The thermal rearrangement of endoperoxides 538a,b.
Scheme 157: The transformation of peroxides 541.
Scheme 158: The thermal rearrangements of strained cyclic peroxides.
Scheme 159: The thermal rearrangement of diacyl peroxide 551 in the synthesis of C4-epi-lomaiviticin B core 553....
Scheme 160: The 1O2 oxidation of tryptophan (554) and rearrangement of dioxetane intermediate 555.
Scheme 161: The Fe(II)-promoted cleavage of aryl-substituted bicyclic peroxides.
Scheme 162: The proposed mechanism of the Fe(II)-promoted rearrangement of 557a–c.
Scheme 163: The reaction of dioxolane 563 with Fe(II) sulfate.
Scheme 164: Fe(II)-promoted rearrangement of 1,2-dioxane 565.
Scheme 165: Fe(II) cysteinate-promoted rearrangement of 1,2-dioxolane 568.
Scheme 166: The transformation of 1,2-dioxanes 572a–c under the action of FeCl2.
Scheme 167: Fe(II) cysteinate-promoted transformation of tetraoxane 574.
Scheme 168: The CoTPP-catalyzed transformation of bicyclic endoperoxides 600a–d.
Scheme 169: The CoTPP-catalyzed transformation of epoxy-1,2-dioxanes.
Scheme 170: The Ru(II)-catalyzed reactions of 1,4-endoperoxide 261g.
Scheme 171: The Ru(II)-catalyzed transformation as a key step in the synthesis of elyiapyrone A (610) from 1,4-...
Scheme 172: Peroxides with antimalarial activity.
Scheme 173: The interaction of iron ions with artemisinin (616).
Scheme 174: The interaction of FeCl2 with 1,2-dioxanes 623, 624.
Scheme 175: The mechanism of reaction 623 and 624 with Fe(II)Cl2.
Scheme 176: The reaction of bicyclic natural endoperoxides G3-factors 631–633 with FeSO4.
Scheme 177: The transformation of terpene cardamom peroxide 639.
Scheme 178: The different ways of the cleavage of tetraoxane 643.
Scheme 179: The LC–MS analysis of interaction of tetraoxane 646 with iron(II)heme 647.
Scheme 180: The rearrangement of 3,6-epidioxy-1,10-bisaboladiene (EDBD, 649).
Scheme 181: Easily oxidized substrates.
Scheme 182: Biopathway of synthesis of prostaglandins.
Scheme 183: The reduction and rearrangements of isoprostanes.
Scheme 184: The partial mechanism for linoleate 658 oxidation.
Scheme 185: The transformation of lipid hydroperoxide.
Scheme 186: The acid-catalyzed cleavage of the product from free-radical oxidation of cholesterol (667).
Scheme 187: Two pathways of catechols oxidation.
Scheme 188: Criegee-like or Hock-like rearrangement of the intermediate hydroperoxide 675 in dioxygenase enzyme...
Scheme 189: Carotinoides 679 cleavage by carotenoid cleavage dioxygenases.
A simple copper-catalyzed two-step one-pot synthesis of indolo[1,2-a]quinazoline
- Chunpu Li,
- Lei Zhang,
- Shuangjie Shu and
- Hong Liu
Beilstein J. Org. Chem. 2014, 10, 2441–2447, doi:10.3762/bjoc.10.254
- pharmaceutical compounds [1][2][3][4][5]. In particular, tetracyclic compounds containing the indole substructure represent an important structural motif in a variety of bioactive compounds, such as antitumor agents A [6] and antifungal agents B [7] (Figure 1). Therefore, it is necessary to develop efficient and
Graphical Abstract
Figure 1: Representative examples of bioactive tetracyclic compounds containing the indole motif.
Scheme 1: Synthetic route for indolo[1,2-a]quinazoline derivatives by a sequential Ullmann-type C–C and C–N c...
Reversibly locked thionucleobase pairs in DNA to study base flipping enzymes
- Christine Beuck and
- Elmar Weinhold
Beilstein J. Org. Chem. 2014, 10, 2293–2306, doi:10.3762/bjoc.10.239
- derivatives and other interstrand cross-linking reagents as antitumor agents. Chemically synthesized DNA cross-links are of great interest to mimic the reaction products of cross-linking agents acting in vivo [6][7][8] and to mechanistically study enzymes that rely on opening Watson–Crick base pairs by base
Graphical Abstract
Figure 1: Covalent cross-linking of a I6S/U4S or G6S/U4S base pair within duplex ODN 1∙2 (a) by bis-alkylatio...
Figure 2: Characterization of HPLC-purified cross-linked duplex 1I6S-Et-S4U2 (a) by denaturing anion exchange...
Figure 3: Characterization of HPLC-purified cross-linked duplex 1G6S-Et-S4U2 (a) by denaturing anion exchange...
Figure 4: Opening and traceless linker removal of the cross-linked duplexes 1I6S-Et-S4U2 and 1G6S-Et-S4U2 by ...
Figure 5: UV time course of opening of the cross-link in duplex 1I6S-Et-S4U2 with the thiol nucleophiles DTT ...
Figure 6: Competition binding of M.TaqI to DNA with unlocked and locked target base pairs. Increasing amounts...
