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Search for "glucose" in Full Text gives 357 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Tenacibactins K–M, cytotoxic siderophores from a coral-associated gliding bacterium of the genus Tenacibaculum
- Yasuhiro Igarashi,
- Yiwei Ge,
- Tao Zhou,
- Amit Raj Sharma,
- Enjuro Harunari,
- Naoya Oku and
- Agus Trianto
Beilstein J. Org. Chem. 2022, 18, 110–119, doi:10.3762/bjoc.18.12
- mL of A11M production medium (pH 7.0) consisting of 2.5% soluble starch, 0.2% glucose, 0.5% yeast extract, 0.5% Hipolypeptone (Wako Pure Chemical Industries, Ltd), NZ amine (Wako Pure Chemical Industries, Ltd), CaCO3 0.3%, and 1% Diaion HP-20 (Mitsubishi Chemical Co.) in natural sea water. The
Graphical Abstract
Figure 1: Structures of tenacibactins K–M (1–3).
Figure 2: Key 2D-NMR correlations for 1–3.
Figure 3: (a) Partial 1H NMR spectra of 1 at 25 and 50 °C in DMSO-d6; (b) magnified HMBC spectrum of 1 at 25 ...
Figure 4: MS/MS spectrum of 1 acquired on a quadrupole time-of-flight mass spectrometer in the negative ion m...
Scheme 1: MS/MS fragmentation pathway for compound 1.
Unsaturated fatty acids and a prenylated tryptophan derivative from a rare actinomycete of the genus Couchioplanes
- Shun Saito,
- Kanji Indo,
- Naoya Oku,
- Hisayuki Komaki,
- Masashi Kawasaki and
- Yasuhiro Igarashi
Beilstein J. Org. Chem. 2021, 17, 2939–2949, doi:10.3762/bjoc.17.203
- extract 0.5%, and glucose 0.2% (pH 7.3) solidified by agar 2%, was inoculated into test tubes (inner diameter, 15 mm; length 16.5 cm) each containing 5 mL of YG seed medium consisting of glucose 1% and yeast extract 1% (pH 7.0). The tubes were shaken at 260 strokes/min at 28 °C for 3 days (TC-500R
- days. Isolation of compounds 1–5 Compounds 1–5 were obtained from a culture fermented in A16 production medium with a composition of glucose 2%, Pharmamedia® (Traders Protein, Memphis, TN, USA) 1%, and CaCO3 0.5%. The pH of the medium was adjusted to 7.0 before autoclaving. At the end of fermentation
- , 221.1148; found, 221.1149. Isolation of 6 Compound 6 was obtained from a culture fermented in modified V22 production medium with a composition of soluble starch 1%, glucose 0.5%, NZ Amine, Type A 0.3%, yeast extract 0.2%, Tryptone 0.5% K2HPO4 0.1%, MgSO4·7H2O 0.05%, and CaCO3 0.3%. The pH of the medium
Graphical Abstract
Figure 1: Structures of 1–6.
Figure 2: COSY, key HMBC and NOESY correlations of 1–5.
Figure 3: 1H NMR spectra and partial chemical shift assignments for MPA esters 4'a–4'd. Upper: (R)-MPA acylat...
Figure 4: Chiral phase HPLC analysis of methyl ester 4'. Italicized numbers indicate peak areas.
Figure 5: COSY and key HMBC correlations observed for 6.
Figure 6: ΔδH(S-R) values in ppm calculated from PGME amides 6a and 6b.
Figure 7: Selected examples of the related compounds derived from the strains in the genus Streptomyces (a) a...
The ethoxycarbonyl group as both activating and protective group in N-acyl-Pictet–Spengler reactions using methoxystyrenes. A short approach to racemic 1-benzyltetrahydroisoquinoline alkaloids
- Marco Keller,
- Karl Sauvageot-Witzku,
- Franz Geisslinger,
- Nicole Urban,
- Michael Schaefer,
- Karin Bartel and
- Franz Bracher
Beilstein J. Org. Chem. 2021, 17, 2716–2725, doi:10.3762/bjoc.17.183
- ) suspensions were loaded with 4 µM fluo-4/AM (Life Technologies, Eugene, OR) for 30 min at 37 °C. After centrifugation, cells were resuspended in HEPES-buffered saline (HBS), containing 132 mM NaCl, 6 mM KCl, 1 mM MgCl2, 1 mM CaCl2, 10 mM HEPES, and 5.5 mM ᴅ-glucose (pH was adjusted to 7.4 with NaOH) and
Graphical Abstract
Figure 1: Prominent synthetic approaches to 1-benzyltetrahydroisoquinolines: Bischler–Napieralski, Pictet–Spe...
Figure 2: Structures of N-methylcoclaurine (1) and the ten 1-benzyl-1,2,3,4-tetrahydroisoquinoline alkaloids ...
Figure 3: Two routes using N- and O-alkoxycarbonylated building blocks for the synthesis of phenolic N-methyl...
Figure 4: Structures of the building blocks A1–A4 (N-ethoxycarbonyl phenethylamines) and B1–B3 (ω-methoxystyr...
Figure 5: Biological activity. Antiproliferative effects of the 1-benzyltetrahydroisoquinoline alkaloids in A...
Phenolic constituents from twigs of Aleurites fordii and their biological activities
- Kyoung Jin Park,
- Won Se Suh,
- Da Hye Yoon,
- Chung Sub Kim,
- Sun Yeou Kim and
- Kang Ro Lee
Beilstein J. Org. Chem. 2021, 17, 2329–2339, doi:10.3762/bjoc.17.151
- ′), 118.2 (C-6), 115.8 (C-2′), 115.3 (C-6′), 114.6 (C-5), and 109.1 (C-2)] and six glucose carbons [δC 103.0 (C-1′′), 76.7 (C-3′′), 76.5 (C-5′′), 73.7 (C-2′′), 70.2 (C-4′′), and 61.3 (C-6′′)]. The spectroscopic data of compound 1 suggested that it is a typical dihydrobenzofuran neolignan glycoside [9][10
- (Figure 2). The locations of the glucose unit and the methoxy group were confirmed from the observed HMBC correlations of H-1′′/C-9′ and 3-OCH3/C-3, respectively (Figure 2). Acid hydrolysis of 1 was conducted to analyze the aglycone and sugar moiety. The structure of the aglycone (1a) was confirmed as
- demethyldihydrodehydrodiconiferyl alcohol based on the comparison of 1H NMR and MS data [13]. The relatively large coupling constant of the anomeric proton (7.8 Hz) confirmed that the glucose is combined as β-form [14]. ᴅ-Glucose was identified by co-TLC with a standard sample [CHCl3/MeOH/H2O 2:1:0.1, Rf = 0.3)] and GC–MS analysis
Graphical Abstract
Figure 1: Chemical structures of compounds 1–19.
Figure 2: Key COSY and HMBC correlations of compounds 1–3, 15, and 16 and key NOESY correlation of 2.
(Phenylamino)pyrimidine-1,2,3-triazole derivatives as analogs of imatinib: searching for novel compounds against chronic myeloid leukemia
- Luiz Claudio Ferreira Pimentel,
- Lucas Villas Boas Hoelz,
- Henayle Fernandes Canzian,
- Frederico Silva Castelo Branco,
- Andressa Paula de Oliveira,
- Vinicius Rangel Campos,
- Floriano Paes Silva Júnior,
- Rafael Ferreira Dantas,
- Jackson Antônio Lamounier Camargos Resende,
- Anna Claudia Cunha,
- Nubia Boechat and
- Mônica Macedo Bastos
Beilstein J. Org. Chem. 2021, 17, 2260–2269, doi:10.3762/bjoc.17.144
- -2029TM). The K562 strain was grown in RPMI-1640 medium according to the provider's recommendations [47][48]. Cultivation of WSS-1 cells was performed in DMEM high glucose medium (Vitrocell) according to ATCC recommendations. The media were supplemented with 10% fetal bovine serum (FBS) and 50 mg/MI of
Graphical Abstract
Figure 1: Proposed structural modifications to obtain triazole derivatives 1a, b and 2a–j.
Scheme 1: Synthetic route of the triazole derivatives 1a,b, and 2a–j.
Figure 2: Asymmetric unit representation of the 1,2,3-triazole derivative 2b. Displacement ellipsoids are dra...
Figure 3: Screening of the triazole derivatives of imatinib 1a,b, and 2a–j at concentrations of 1 μM and 10 μ...
Figure 4: Interaction maps of IMT, 2c, 2d, and 2g with the BCR-Abl-1 structure (PDB code: 3PYY), showing ster...
Nomimicins B–D, new tetronate-class polyketides from a marine-derived actinomycete of the genus Actinomadura
- Zhiwei Zhang,
- Tao Zhou,
- Taehui Yang,
- Keisuke Fukaya,
- Enjuro Harunari,
- Shun Saito,
- Katsuhisa Yamada,
- Chiaki Imada,
- Daisuke Urabe and
- Yasuhiro Igarashi
Beilstein J. Org. Chem. 2021, 17, 2194–2202, doi:10.3762/bjoc.17.141
- Actinomadura geliboluensis A8036T (DDBJ accession number HQ157187). Fermentation Actinomadura sp. AKA43 cultured on Bn-2 agar medium (soluble starch 0.5%, glucose 0.5%, meat extract (Kyokuto Pharmaceutical Industrial Co., Ltd.) 0.1%, yeast extract (Difco Laboratories) 0.1%, NZ-case (Wako Chemicals USA, Inc
- .) 0.2%, NaCl 0.2%, CaCO3 0.1%, and agar 1.5% in distilled water of pH 7.0) was inoculated into a 500 mL K-1 flask containing 100 mL of the V-22 seed medium (soluble starch 1%, glucose 0.5%, NZ-case 0.3%, yeast extract 0.2%, tryptone (Difco Laboratories) 0.5%, K2HPO4 0.1%, MgSO4·7H2O 0.05%, and CaCO3 0.3
- % in distilled water of pH 7.0). The flask was shaken on a rotary shaker (200 rpm) at 30 °C for 4 days. For the production of nomimicins B (1) and C (2), the seed culture (3 mL) was transferred into 20 500 mL K-1 flasks, each containing 100 mL of the A16 production medium (glucose 2%, Pharmamedia
Graphical Abstract
Figure 1: Structures of nomimicins A–D (4 and 1–3).
Figure 2: COSY and key HMBC correlations for 1.
Figure 3: Relative configuration of 1 determined by ROESY analysis.
Figure 4: Experimental ECD spectra of 1, 2, and 4 and calculated ECD spectrum of 4.
Figure 5: Four tautomers 4a–4d of the tetronic acid moiety of 4 and calculated ECD spectra.
Figure 6: COSY and key HMBC correlations for 3.
Figure 7: Relative configuration of 3 determined by NOESY analysis.
Progress and challenges in the synthesis of sequence controlled polysaccharides
- Giulio Fittolani,
- Theodore Tyrikos-Ergas,
- Denisa Vargová,
- Manishkumar A. Chaube and
- Martina Delbianco
Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129
- methodologies or post-extraction modifications are not discussed. Review Glucose-based polysaccharides Cellulose Cellulose is a polymer consisting of glucose units connected by β(1–4) glycosidic bonds. It is mainly found in two allomorphs – Cellulose I (natural) and Cellulose II (synthetic) – that differ in the
- (between 5 and 14) could be obtained tuning the concentration of glucose (2a) or cellobiose (2b) primer acceptor [65]. Polymerization conducted under macromolecular crowding conditions using water-soluble polymers produced hydrogels consisting of cellulose and gelatin networks [54][66][67][68][69]. A study
- geometries were observed with a block wise arrangement of methyl groups. As chemical synthesis offers high flexibility in terms of manipulation, non-carbohydrate moieties can be exploited to guide the geometry of the resulting compounds. β(1–4)-Linked glucose chains were connected parallel via an
Graphical Abstract
Figure 1: Overview of the methods available for the synthesis of polysaccharides. For each method, advantages...
Figure 2: Overview of the classes of polysaccharides discussed in this review. Each section deals with polysa...
Scheme 1: Enzymatic and chemical polymerization approaches provide cellulose oligomers with a non-uniform dis...
Scheme 2: AGA of a collection of cellulose analogues obtained using BBs 6–9. Specifically placed modification...
Figure 3: Chemical structure of the different branches G, X, L, F commonly found in XGs. Names are given foll...
Scheme 3: AGA of XG analogues with defined side chains. The AGA cycle includes coupling (TMSOTf), Fmoc deprot...
Figure 4: Synthetic strategies and issues associated to the formation of the β(1–3) linkage.
Scheme 4: Convergent synthesis of β(1–3)-glucans using a regioselective glycosylation strategy.
Scheme 5: DMF-mediated 1,2-cis glycosylation. A) General mechanism and B) examples of α-glucans prepared usin...
Scheme 6: Synergistic glycosylation strategy employing a nucleophilic modulation strategy (TMSI and Ph3PO) in...
Scheme 7: Different approaches to produce xylans. A) Polymerization techniques including ROP, and B) enzymati...
Scheme 8: A) Synthesis of arabinofuranosyl-decorated xylan oligosaccharides using AGA. Representative compoun...
Scheme 9: Chemoenzymatic synthesis of COS utilizing a lysozyme-catalyzed transglycosylation reaction followed...
Scheme 10: Synthesis of COS using an orthogonal glycosylation strategy based on the use of two different LGs.
Scheme 11: Orthogonal N-PGs permitted the synthesis of COS with different PA.
Scheme 12: AGA of well-defined COS with different PA using two orthogonally protected BBs. The AGA cycle inclu...
Scheme 13: A) AGA of β(1–6)-N-acetylglucosamine hexasaccharide and dodecasaccharide. AGA includes cycles of co...
Figure 5: ‘Double-faced’ chemistry exemplified for ᴅ-Man and ʟ-Rha. Constructing β-Man linkages is considerab...
Figure 6: Implementation of a capping step after each glycosylation cycle for the AGA of a 50mer oligomannosi...
Scheme 14: AGA enabled the synthesis of a linear α(1–6)-mannoside 100mer 93 within 188 h and with an average s...
Scheme 15: The 151mer branched polymannoside was synthesized by a [30 + 30 + 30 + 30 + 31] fragment coupling. ...
Figure 7: PG stereocontrol strategy to obtain β-mannosides. A) The mechanism of the β-mannosylation reaction ...
Scheme 16: A) Mechanism of 1,2-cis stereoselective glycosylation using ManA donors. Once the ManA donor is act...
Figure 8: A) The preferred 4H3 conformation of the gulosyl oxocarbenium ion favors the attack of the alcohol ...
Scheme 17: AGA of type I rhamnans up to 16mer using disaccharide BB 115 and CNPiv PG. The AGA cycle includes c...
Figure 9: Key BBs for the synthesis of the O-antigen of Bacteroides vulgatus up to a 128mer (A) and the CPS o...
Figure 10: Examples of type I and type II galactans synthesized to date.
Figure 11: A) The DTBS PG stabilizes the 3H4 conformation of the Gal oxocarbenium ion favoring the attack of t...
Figure 12: Homogalacturonan oligosaccharides synthesized to date. Access to different patterns of methyl-ester...
Figure 13: GlfT2 from Mycobacterium tuberculosis catalyzes the sequential addition of UPD-Galf donor to a grow...
Figure 14: The poor reactivity of acceptor 137 hindered a stepwise synthesis of the linear galactan backbone a...
Scheme 18: AGA of a linear β(1–5) and β(1–6)-linked galactan 20mer. The AGA cycle includes coupling (NIS/TfOH)...
Figure 15: The 92mer arabinogalactan was synthesized using a [31 + 31 + 30] fragment coupling between a 31mer ...
Scheme 19: Synthesis of the branched arabinofuranose fragment using a six component one-pot synthesis. i) TTBP...
Figure 16: A) Chemical structure and SNFG of the representative disaccharide units forming the GAG backbones, ...
Figure 17: Synthetic challenges associated to the H/HS synthesis.
Scheme 20: Degradation of natural heparin and heparosan generated valuable disaccharides 150 and 151 that can ...
Scheme 21: A) The one-step conversion of cyanohydrin 156 to ʟ-iduronamide 157 represent the key step for the s...
Scheme 22: A) Chemoenzymatic synthesis of heparin structures, using different types of UDP activated natural a...
Scheme 23: Synthesis of the longest synthetic CS chain 181 (24mer) using donor 179 and acceptor 180 in an iter...
Scheme 24: AGA of a collection of HA with different lengths. The AGA cycle includes coupling (TfOH) and Lev de...
A systems-based framework to computationally describe putative transcription factors and signaling pathways regulating glycan biosynthesis
- Theodore Groth,
- Rudiyanto Gunawan and
- Sriram Neelamegham
Beilstein J. Org. Chem. 2021, 17, 1712–1724, doi:10.3762/bjoc.17.119
- by the UDP-glucose:ceramide glucosyltransferase (UGCG), which transfers the first glucose. Following this, lactosylceramide is formed by the action of the β1-4GalT activity of B4GalT5 (and possibly also B4GalT3, 4, and 6). The GalCer core is typically structurally small and is made by UDP
- gangliosides. UGCG is included to consider the addition of glucose to ceramide. ST3GAL5 and ST8SIA enzymes are added to take the core ganglioside structures to the a, b, and c levels. B4GALTs and B4GALNT1 are included to account for ganglioside elongation. Decoration of the gangliosides with sialic acid occurs
Graphical Abstract
Figure 1: A systems glycobiology framework to link multi-OMICs data. a) Cell signaling proceeds to trigger TF...
Figure 2: Analysis workflow: ChiP-Seq provides evidence of TF binding to promoter regions with 0 ≤ RP ≤ 1, qu...
Figure 3: Summary of TFs enriched to glycosylation pathways for luminal and basal breast cancer: The TFs foun...
Figure 4: Luminal breast cancer signaling pathway enrichment and glycogene connections. a) TF-to-glycogene co...
Figure 5: Basal breast cancer signaling pathway enrichments and glycogene connections. a) TF-to-glycogene com...
Figure 6: Summary of TF–glycopathway enrichments across all cancer types: TF enrichments to glycopathways acr...
A recent overview on the synthesis of 1,4,5-trisubstituted 1,2,3-triazoles
- Pezhman Shiri,
- Ali Mohammad Amani and
- Thomas Mayer-Gall
Beilstein J. Org. Chem. 2021, 17, 1600–1628, doi:10.3762/bjoc.17.114
- (n = 1–3). For azides with n = 3, the reaction was performed using alkynes bearing rather complex R2 substituents, such as tyrosine, glucose, clofibrate, vitamin E, estrone, and oleanane triterpenes, which tolerated the reaction conditions and afforded the corresponding triazoles 77 fused with a six
- were screened, producing a moderate to high yield of the desired products. Moreover, alkynes based on complex molecules, such as glucose, tyrosine, clofibrate, estrone, oleanane triterpenes, and vitamin E tolerated the reaction conditions and afforded the corresponding triazolo disulfides (Scheme 28
- . This method was then extended to ketone, tosyl, and phthalimide groups on alkyl azides to produce the desired triazole derivatives. The ethylene glycol-, phenylalanine-, and glucose-derived azides were also good candidates to furnish the triazole derivatives. This protocol provides access to various
Graphical Abstract
Figure 1: Some significant triazole derivatives [8,23-27].
Scheme 1: A general comparison between synthetic routes for disubstituted 1,2,3-triazole derivatives and full...
Scheme 2: Synthesis of formyltriazoles 3 from the treatment of α-bromoacroleins 1 with azides 2.
Scheme 3: A probable mechanism for the synthesis of formyltriazoles 5 from the treatment of α-bromoacroleins 1...
Scheme 4: Synthesis of 1,4,5-trisubstituted 1,2,3-triazoles 8 from the reaction of aryl azides 7 with enamino...
Scheme 5: Proposed mechanism for the synthesis of 1,4,5-trisubstituted 1,2,3-triazoles from the reaction of a...
Scheme 6: Synthesis of 1,4,5-trisubstituted 1,2,3-triazoles 11 from the reaction of primary amines 10 with 1,...
Scheme 7: The proposed mechanism for the synthesis of 1,4,5-trisubstituted 1,2,3-triazoles 11 from the reacti...
Scheme 8: Synthesis of fully decorated 1,2,3-triazoles 19 containing a sulfur-based side chain.
Scheme 9: Mechanism for the formation of fully decorated 1,2,3-triazoles 19 containing a sulfur-based side ch...
Scheme 10: Synthesis of fully decorated 1,2,3-triazole compounds 25 through the regioselective addition and cy...
Scheme 11: A reasonable mechanism for the synthesis of fully decorated 1,2,3-triazole compounds 25 through the...
Scheme 12: Synthesis of 1,4,5-trisubstituted glycosyl-containing 1,2,3-triazole derivatives 30 from the reacti...
Scheme 13: Synthesis of 1,4,5-trisubstituted 1,2,3-triazoles 34 via intramolecular cyclization reaction of ket...
Scheme 14: Synthesis of fully decorated 1,2,3-triazoles 38 from the reaction of aldehydes 35, amines 36, and α...
Scheme 15: A reasonable mechanism for the synthesis of fully decorated 1,2,3-triazoles 38 from the reaction of...
Scheme 16: Synthesis of functionally rich double C- and N-vinylated 1,2,3-triazoles 45 and 47.
Scheme 17: Synthesis of disubstituted 4-chloro-, 4-bromo-, and 4-iodo-1,2,3-triazoles 50.
Scheme 18: a) A general route for SPAAC in polymer chemistry and b) synthesis of a novel pH-sensitive polymeri...
Scheme 19: Synthesis of 5-allenyl-1,2,3-triazoles 60 by the treatment of alkynes 57, azides 58, and propargyli...
Scheme 20: A reasonable mechanism for the synthesis of 5-allenyl-1,2,3-triazoles 60 by the treatment of alkyne...
Scheme 21: Synthesis of 5‐alkynyl-1,2,3-triazoles 69.
Scheme 22: A reasonable mechanism for the synthesis of 5‐alkynyl-1,2,3-triazoles 69.
Scheme 23: Synthesis of sulfur-cycle-fused 1,2,3-triazoles 75 and 77.
Scheme 24: A reasonable mechanism for the synthesis of sulfur-cycle-fused 1,2,3‐triazoles 75 and 77.
Scheme 25: Synthesis of 5-selanyltriazoles 85 from the reaction of ethynylstibanes 82, organic azides 83, and ...
Scheme 26: A mechanism for the synthesis of 5-selanyltriazoles 85 from the reaction of ethynylstibanes 82, org...
Scheme 27: Synthesis of trisubstituted triazoles containing an Sb substituent at position C5 in 93 and 5-unsub...
Scheme 28: Synthesis of asymmetric triazole disulfides 98 from disulfide-containing tert-butyltosyl disulfide 97...
Scheme 29: A mechanism for the synthesis of asymmetric triazole disulfides 98 from disulfide-containing tert-bu...
Scheme 30: Synthesis of triazole-fused sultams 104.
Scheme 31: Synthesis of 1,2,3-triazole-fused tricyclic heterocycles 106.
Scheme 32: A reasonable mechanism for the synthesis of 1,2,3-triazole-fused tricyclic heterocycles 106.
Scheme 33: Synthesis of 5-aryl-substituted 1,2,3-triazole derivatives 112.
Scheme 34: A reasonable mechanism for the synthesis of 5-aryl-substituted 1,2,3-triazole derivatives 112.
Scheme 35: Synthesis of 1,4,5-trisubstituted 1,2,3-triazole-5-carboxamides 119.
Scheme 36: A probable mechanism for the synthesis of 1,4,5-trisubstituted 1,2,3-triazole-5-carboxamides 119.
Scheme 37: Synthesis of fully decorated triazoles 125 via the Pd/C-catalyzed arylation of disubstituted triazo...
Scheme 38: Synthesis of triazolo[1,5-a]indolones 131.
Scheme 39: Synthesis of unsymmetrically substituted triazole-fused enediyne systems 135 and 5-aryl-4-ethynyltr...
Scheme 40: Synthesis of Pd/Cu-BNP 139 and application of 139 in the synthesis of polycyclic triazoles 142.
Scheme 41: A probable mechanism for the synthesis of polycyclic triazoles 142.
Scheme 42: Synthesis of highly functionalized 1,2,3-triazole-fused 5-, 6-, and 7-membered rings 152–154.
Scheme 43: A probable mechanism for the synthesis of highly functionalized 1,2,3-triazole-fused 5-, 6-, and 7-...
Scheme 44: Synthesis of fully functionalized 1,2,3-triazolo-fused chromenes 162, 164, and 166 via the intramol...
Scheme 45: Ru-catalyzed synthesis of fully decorated triazoles 172.
Scheme 46: Synthesis of 4-cyano-1,2,3-triazoles 175.
Scheme 47: Synthesis of functionalized triazoles from the reaction of 1-alkyltriazenes 176 and azides 177 and ...
Scheme 48: Mechanism for the synthesis of functionalized triazoles from the reaction of 1-alkyltriazenes 176 a...
Recent advances in the application of isoindigo derivatives in materials chemistry
- Andrei V. Bogdanov and
- Vladimir F. Mironov
Beilstein J. Org. Chem. 2021, 17, 1533–1564, doi:10.3762/bjoc.17.111
- glucose in solution (see polymer 62) [108][109]. The limit of sensitivity of the sensor for nitrogen dioxide was 60 ppm and for glucose 0.026 mM. For the example of the fairly simple arylamine series 63, the possibility of using isoindigo polymer for the detection of explosives (trinitrophenol and
Graphical Abstract
Scheme 1: Representatives of isomeric bisoxindoles.
Scheme 2: Isoindigo-based OSCs with the best efficiency.
Scheme 3: Monoisoindigos with preferred 6,6'-substitution.
Scheme 4: Possibility of aromatic–quinoid structural transition.
Scheme 5: Isoindigo structures with incorporated acceptor nitrogen heterocycles.
Scheme 6: Monoisoindigos bearing pyrenyl substituents.
Scheme 7: p-Alkoxyphenylene-embedded thienylisoindigo with different acceptor anchor units.
Scheme 8: Nonfullerene OSC based on perylene diimide-derived isoindigo.
Scheme 9: Isoindigo as an additive in all-polymer OSCs.
Scheme 10: Bisisoindigos with different linker structures.
Scheme 11: Nonthiophene oligomeric monoisoindigos for OSCs.
Scheme 12: The simplest examples of polymers with a monothienylisoindigo monomeric unit.
Scheme 13: Monothienylisoindigos bearing π-extended electron-donor backbones.
Scheme 14: Role of fluorination and the molecular weight on OSC efficiency on the base of the bithiopheneisoin...
Scheme 15: Trithiopheneisoindigo polymers with variation in the substituent structure.
Scheme 16: Polymeric thienyl-linked bisisoindigos for OSCs.
Scheme 17: Isoindigo bearing the thieno[3,2-b]thiophene structural motif as donor component of OSCs.
Scheme 18: Thienylisoindigos with incorporated aromatic unit.
Scheme 19: One-component nonfullerene OSCs on the base of isoindigo.
Scheme 20: Isoindigo-based nonthiophene aza aromatic polymers as acceptor components of OSCs.
Scheme 21: Polymers with isoindigo substituent as side-chain photon trap.
Scheme 22: Isoindigo derivatives for OFET technology with the best mobility.
Scheme 23: Monoisoindigos as low-molecular-weight semiconductors.
Scheme 24: Polymeric bithiopheneisoindigos for OFET creation.
Scheme 25: Fluorination as a tool to improve isoindigo-based OFET devices.
Scheme 26: Diversely DPP–isoindigo-conjugated polymers for OFETs.
Scheme 27: Isoindigoid homopolymers with differing rigidity.
Scheme 28: Isoindigo-based materials with extended π-conjugation.
Scheme 29: Poly(isoindigothiophene) compounds as sensors for ammonia.
Scheme 30: Sensor devices based on poly(isoindigoaryl) compounds.
Scheme 31: Isoindigo polymers for miscellaneous applications.
Scheme 32: Mono-, rod-like, and polymeric isoindigos as agents for photoacoustic and photothermal cancer thera...
Double-headed nucleosides: Synthesis and applications
- Vineet Verma,
- Jyotirmoy Maity,
- Vipin K. Maikhuri,
- Ritika Sharma,
- Himal K. Ganguly and
- Ashok K. Prasad
Beilstein J. Org. Chem. 2021, 17, 1392–1439, doi:10.3762/bjoc.17.98
- :5,6-di-O-isopropylidene-ᴅ-glucose [50]. Furanoside 42 was reacted with the silyl-protected nucleobases 43a–c and 47a,b in the presence of trimethylsilyl trifluoromethanesulfonate in acetonitrile to give the 3′-azido-3′-deoxy-β-ᴅ-ribonucleosides 44a–c and 48a,b via Vorbrüggen coupling reaction. The
Graphical Abstract
Figure 1: Double-headed nucleosides. B1 and B2 = nucleobases or heterocyclic/carbocyclic moieties; L = linker....
Scheme 1: Synthesis of 2′-(pyrimidin-1-yl)methyl- or 2′-(purin-9-yl)methyl-substituted double-headed nucleosi...
Scheme 2: Synthesis of double-headed nucleoside 7 having two cytosine moieties.
Scheme 3: Synthesis of double-headed nucleoside 2′-deoxy-2′-C-(2-(thymine-1-yl)ethyl)-uridine (11).
Scheme 4: Double-headed nucleosides 14 and 15 obtained by click reaction.
Scheme 5: Synthesis of the double-headed nucleoside 19.
Scheme 6: Synthesis of the double-headed nucleosides 24 and 25.
Scheme 7: Synthesis of double-headed nucleosides 28 and 29.
Scheme 8: Synthesis of double-headed nucleoside 33.
Scheme 9: Synthesis of double-headed nucleoside 37.
Scheme 10: Synthesis of the double-headed nucleoside 1-(5′-O-(4,4′-dimethoxytrityl)-2′-C-((4-(pyren-1-yl)-1,2,...
Scheme 11: Synthesis of triazole-containing double-headed ribonucleosides 46a–c and 50a–e.
Scheme 12: Synthesis of double-headed nucleosides 54a–g.
Scheme 13: Synthesis of double-headed nucleosides 59 and 60.
Scheme 14: Synthesis of the double-headed nucleosides 63 and 64.
Scheme 15: Synthesis of double-headed nucleosides 66a–c.
Scheme 16: Synthesis of benzoxazole-containing double-headed nucleosides 69 and 71 from 5′-amino-5′-deoxynucle...
Scheme 17: Synthesis of 4′-C-((N6-benzoyladenin-9-yl)methyl)thymidine (75) and 4′-C-((thymin-1-yl)methyl)thymi...
Scheme 18: Synthesis of double-headed nucleosides 5′-(adenine-9-yl)-5′-deoxythymidine (79) and 5′-(adenine-9-y...
Scheme 19: Synthesis of double-headed nucleosides 85–87 via reversed nucleosides methodology.
Scheme 20: Double-headed nucleosides 91 and 92 derived from ω-terminal-acetylenic sugar derivatives 90a,b.
Scheme 21: Synthesis of double-headed nucleosides 96a–g.
Scheme 22: Synthesis of double-headed nucleosides 100 and 103.
Scheme 23: Double-headed nucleosides 104 and 105 with a triazole motif.
Scheme 24: Synthesis of the double-headed nucleosides 107 and 108.
Scheme 25: Synthesis of double-headed nucleoside 110 with additional nucleobase in 5′-(S)-C-position joined th...
Scheme 26: Synthesis of double-headed nucleosides 111–113 with additional nucleobases in the 5′-(S)-C-position...
Scheme 27: Synthesis of double-headed nucleoside 114 by click reaction.
Scheme 28: Synthesis of double-headed nucleosides 118 with an additional nucleobase at the 5′-(S)-C-position.
Scheme 29: Synthesis of bicyclic double-headed nucleoside 122.
Scheme 30: Synthesis of double-headed nucleosides 125a–c derived from 2′-amino-LNA.
Scheme 31: Double-headed nucleoside 127 obtained by click reaction.
Scheme 32: Synthesis of double-headed nucleoside 130.
Scheme 33: Double-headed nucleosides 132a–d and 134a–d synthesized by Sonogashira cross coupling reaction.
Scheme 34: Synthesis of double-headed nucleosides 137 and 138 via Suzuki coupling.
Scheme 35: Synthesis of double-headed nucleosides 140 and 141 via Sonogashira cross coupling reaction.
Scheme 36: Synthesis of double-headed nucleoside 143.
Scheme 37: Synthesis of the double-headed nucleoside 146.
Scheme 38: Synthesis of 5-C-alkynyl-functionalized double-headed nucleosides 151a–d.
Scheme 39: Synthesis of 5-C-triazolyl-functionalized double-headed nucleosides 154a, b.
Scheme 40: Synthesis of double-headed nucleosides 157a–c.
Scheme 41: Synthesis of double-headed nucleoside 159, phosphoramidite 160 and the corresponding nucleotide mon...
Scheme 42: Synthesis of double-headed nucleoside 163, phosphoramidite 164 and the corresponding nucleotide mon...
Scheme 43: Synthesis of double-headed nucleoside 167, phosphoramidite 168, and the corresponding nucleotide mo...
Scheme 44: Synthesis of double-headed nucleoside 171, phosphoramidite 172, and the corresponding nucleotide mo...
Scheme 45: Synthesis of double-headed nucleoside 175, phosphoramidite 176, and the corresponding nucleotide mo...
Scheme 46: Synthesis of double-headed nucleoside 178.
Scheme 47: Synthesis of the double-headed nucleosides 181 and 183.
Scheme 48: Alternative synthesis of the double-headed nucleoside 183.
Scheme 49: Synthesis of double-headed nucleoside 188 through thermal [2 + 3] sydnone–alkyne cycloaddition reac...
Scheme 50: Synthesis of the double-headed nucleosides 190 and 191.
Scheme 51: Synthesis of 1-((5S)-2,3,4-tri-O-acetyl-5-(2,6-dichloropurin-9-yl)-β-ᴅ-xylopyranosyl)uracil (195).
Scheme 52: Synthesis of hexopyranosyl double-headed pyrimidine homonucleosides 200a–c.
Figure 2: 3′-C-Ethynyl-β-ᴅ-allopyranonucleoside derivatives 201a–f.
Scheme 53: Synthesis of 3′-C-(1,4-disubstituted-1,2,3-triazolyl)-double-headed pyranonucleosides 203–207.
Scheme 54: Synthesis of 3′-C-(1,4-disubstituted-1,2,3-triazolyl)-double-headed pyranonucleosides 208 and 209.
Scheme 55: Synthesis of 3′-C-(1,4-disubstituted-1,2,3-triazolyl)-double-headed pyranonucleoside 210.
Scheme 56: Synthesis of double-headed acyclic nucleosides (2S,3R)-1,4-bis(thymine-1-yl)butane-2,3-diol (213a) ...
Scheme 57: Synthesis of double-headed acyclic nucleosides (2R,3S)-1,4-bis(thymine-1-yl)butane-2,3-diol (213c) ...
Scheme 58: Synthesis of double-headed acetylated 1,3,4-oxadiazino[6,5-b]indolium-substituted C-nucleosides 218b...
Scheme 59: Synthesis of double-headed acyclic nucleoside 222.
Scheme 60: Synthesis of functionalized 1,2-bis(1,2,4-triazol-3-yl)ethane-1,2-diols 223a–f.
Scheme 61: Synthesis of acyclic double-headed 1,2,4-triazino[5,6-b]indole C-nucleosides 226–231.
Scheme 62: Synthesis of double-headed 1,3,4-thiadiazoline, 1,3,4-oxadiazoline, and 1,2,4-triazoline acyclo C-n...
Scheme 63: Synthesis of double-headed acyclo C-nucleosides 240–242.
Scheme 64: Synthesis of double-headed acyclo C-nucleoside 246.
Scheme 65: Synthesis of acyclo double-headed nucleoside 250.
Scheme 66: Synthesis of acyclo double-headed nucleoside 253.
Scheme 67: Synthesis of acyclo double-headed nucleosides 259a–d.
Scheme 68: Synthesis of acyclo double-headed nucleoside 261.
Analogs of the carotane antibiotic fulvoferruginin from submerged cultures of a Thai Marasmius sp.
- Birthe Sandargo,
- Leon Kaysan,
- Rémy B. Teponno,
- Christian Richter,
- Benjarong Thongbai,
- Frank Surup and
- Marc Stadler
Beilstein J. Org. Chem. 2021, 17, 1385–1391, doi:10.3762/bjoc.17.97
- assay in 96-well microtiter plates with YM6.3 media (10 g/L malt extract, 4 g/L glucose, 4 g/L yeast extract, pH 6.3) for filamentous fungi and yeasts, and with BD DifcoTM Mueller Hinton Broth for bacteria. The antimicrobial assays were performed as previously described [13]. Cytotoxicity assay The
Graphical Abstract
Figure 1: Structures of fulvoferruginin (1) and the newly isolated derivatives fulvoferruginins B–F (2–6).
Figure 2: KEY HMBC (arrows) and COSY (thick bonds) correlations of compounds 2 and 3.
Figure 3: Key ROESY correlations of metabolite 3.
A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries
- Guido Gambacorta,
- James S. Sharley and
- Ian R. Baxendale
Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90
Graphical Abstract
Figure 1: Representative shares of the global F&F market (2018) segmented on their applications [1].
Figure 2: General structure of an international fragrance company [2].
Figure 3: The Michael Edwards fragrance wheel.
Figure 4: Examples of oriental (1–3), woody (4–7), fresh (8–10), and floral (11 and 12) notes.
Figure 5: A basic depiction of batch vs flow.
Scheme 1: Examples of reactions for which flow processing outperforms batch.
Scheme 2: Some industrially important aldol-based transformations.
Scheme 3: Biphasic continuous aldol reactions of acetone and various aldehydes.
Scheme 4: Aldol synthesis of 43 in flow using LiHMDS as the base.
Scheme 5: A semi-continuous synthesis of doravirine (49) involving a key aldol reaction.
Scheme 6: Enantioselective aldol reaction using 5-(pyrrolidin-2-yl)tetrazole (51) as catalyst in a microreact...
Scheme 7: Gröger's example of asymmetric aldol reaction in aqueous media.
Figure 6: Immobilised reagent column reactor types.
Scheme 8: Photoinduced thiol–ene coupling preparation of silica-supported 5-(pyrrolidin-2-yl)tetrazole 63 and...
Scheme 9: Continuous-flow approach for enantioselective aldol reactions using the supported catalyst 67.
Scheme 10: Ötvös’ employment of a solid-supported peptide aldol catalyst in flow.
Scheme 11: The use of proline tetrazole packed in a column for aldol reaction between cyclohexanone (65) and 2...
Scheme 12: Schematic diagram of an aminosilane-grafted Si-Zr-Ti/PAI-HF reactor for continuous-flow aldol and n...
Scheme 13: Continuous-flow condensation for the synthesis of the intermediate 76 to nabumetone (77) and Microi...
Scheme 14: Synthesis of ψ-Ionone (80) in continuous-flow via aldol condensation between citral (79) and aceton...
Scheme 15: Synthesis of β-methyl-ionones (83) from citral (79) in flow. The steps are separately described, an...
Scheme 16: Continuous-flow synthesis of 85 from 84 described by Gavriilidis et al.
Scheme 17: Continuous-flow scCO2 apparatus for the synthesis of 2-methylpentanal (87) and the self-condensed u...
Scheme 18: Chen’s two-step flow synthesis of coumarin (90).
Scheme 19: Pechmann condensation for the synthesis of 7-hydroxyxcoumarin (93) in flow. The setup extended to c...
Scheme 20: Synthesis of the dihydrojasmonate 35 exploiting nitro derivative proposed by Ballini et al.
Scheme 21: Silica-supported amines as heterogeneous catalyst for nitroaldol condensation in flow.
Scheme 22: Flow apparatus for the nitroaldol condensation of p-hydroxybenzaldehyde (102) to nitrostyrene 103 a...
Scheme 23: Nitroaldol reaction of 64 to 105 employing a quaternary ammonium functionalised PANF.
Scheme 24: Enantioselective nitroaldol condensation for the synthesis of 108 under flow conditions.
Scheme 25: Enatioselective synthesis of 1,2-aminoalcohol 110 via a copper-catalysed nitroaldol condensation.
Scheme 26: Examples of Knoevenagel condensations applied for fragrance components.
Scheme 27: Flow apparatus for Knoevenagel condensation described in 1989 by Venturello et al.
Scheme 28: Knoevenagel reaction using a coated multichannel membrane microreactor.
Scheme 29: Continuous-flow apparatus for Knoevenagel condensation employing sugar cane bagasse as support deve...
Scheme 30: Knoevenagel reaction for the synthesis of 131–135 in flow using an amine-functionalised silica gel. ...
Scheme 31: Continuous-flow synthesis of compound 137, a key intermediate for the synthesis of pregabalin (138)...
Scheme 32: Continuous solvent-free apparatus applied for the synthesis of compounds 140–143 using a TSE. Throu...
Scheme 33: Lewis et al. developed a spinning disc reactor for Darzens condensation of 144 and a ketone to furn...
Scheme 34: Some key industrial applications of conjugate additions in the F&F industry.
Scheme 35: Continuous-flow synthesis of 4-(2-hydroxyethyl)thiomorpholine 1,1-dioxide (156) via double conjugat...
Scheme 36: Continuous-flow system for Michael addition using CsF on alumina as the catalyst.
Scheme 37: Calcium chloride-catalysed asymmetric Michael addition using an immobilised chiral ligand.
Scheme 38: Continuous multistep synthesis for the preparation of (R)-rolipram (173). Si-NH2: primary amine-fun...
Scheme 39: Continuous-flow Michael addition using ion exchange resin Amberlyst® A26.
Scheme 40: Preparation of the heterogeneous catalyst 181 developed by Paixão et al. exploiting Ugi multicompon...
Scheme 41: Continuous-flow system developed by the Paixão’s group for the preparation of Michael asymmetric ad...
Scheme 42: Continuous-flow synthesis of nitroaldols catalysed by supported catalyst 184 developed by Wennemers...
Scheme 43: Heterogenous polystyrene-supported catalysts developed by Pericàs and co-workers.
Scheme 44: PANF-supported pyrrolidine catalyst for the conjugate addition of cyclohexanone (65) and trans-β-ni...
Scheme 45: Synthesis of (−)-paroxetine precursor 195 developed by Ötvös, Pericàs, and Kappe.
Scheme 46: Continuous-flow approach for the 5-step synthesis of (−)-oseltamivir (201) as devised by Hayashi an...
Scheme 47: Continuous-flow enzyme-catalysed Michael addition.
Scheme 48: Continuous-flow copper-catalysed 1,4 conjugate addition of Grignard reagents to enones. Reprinted w...
Scheme 49: A collection of commonly encountered hydrogenation reactions.
Figure 7: The ThalesNano H-Cube® continuous-flow hydrogenator.
Scheme 50: Chemoselective reduction of an α,β-unsaturated ketone using the H-Cube® reactor.
Scheme 51: Incorporation of Lindlar’s catalyst into the H-Cube® reactor for the reduction of an alkyne.
Scheme 52: Continuous-flow semi-hydrogenation of alkyne 208 to 209 using SACs with H-Cube® system.
Figure 8: The standard setups for tube-in-tube gas–liquid reactor units.
Scheme 53: Homogeneous hydrogenation of olefins using a tube-in-tube reactor setup.
Scheme 54: Recyclable heterogeneous flow hydrogenation system.
Scheme 55: Leadbeater’s reverse tube-in-tube hydrogenation system for olefin reductions.
Scheme 56: a) Hydrogenation using a Pd-immobilised microchannel reactor (MCR) and b) a representation of the i...
Scheme 57: Hydrogenation of alkyne 238 exploiting segmented flow in a Pd-immobilised capillary reactor.
Scheme 58: Continuous hydrogenation system for the preparation of cyrene (241) from (−)-levoglucosenone (240).
Scheme 59: Continuous hydrogenation system based on CSMs developed by Hornung et al.
Scheme 60: Chemoselective reduction of carbonyls (ketones over aldehydes) in flow.
Scheme 61: Continuous system for the semi-hydrogenation of 256 and 258, developed by Galarneau et al.
Scheme 62: Continuous synthesis of biodiesel fuel 261 from lignin-derived furfural acetone (260).
Scheme 63: Continuous synthesis of γ-valerolacetone (263) via CTH developed by Pineda et al.
Scheme 64: Continuous hydrogenation of lignin-derived biomass (products 265, 266, and 267) using a sustainable...
Scheme 65: Ru/C or Rh/C-catalysed hydrogenation of arene in flow as developed by Sajiki et al.
Scheme 66: Polysilane-immobilized Rh–Pt-catalysed hydrogenation of arenes in flow by Kobayashi et al.
Scheme 67: High-pressure in-line mixing of H2 for the asymmetric reduction of 278 at pilot scale with a 73 L p...
Figure 9: Picture of the PFR employed at Eli Lilly & Co. for the continuous hydrogenation of 278 [287]. Reprinted ...
Scheme 68: Continuous-flow asymmetric hydrogenation using Oppolzer's sultam 280 as chiral auxiliary.
Scheme 69: Some examples of industrially important oxidation reactions in the F&F industry. CFL: compact fluor...
Scheme 70: Gold-catalysed heterogeneous oxidation of alcohols in flow.
Scheme 71: Uozumi’s ARP-Pt flow oxidation protocol.
Scheme 72: High-throughput screening of aldehyde oxidation in flow using an in-line GC.
Scheme 73: Permanganate-mediated Nef oxidation of nitroalkanes in flow with the use of in-line sonication to p...
Scheme 74: Continuous-flow aerobic anti-Markovnikov Wacker oxidation.
Scheme 75: Continuous-flow oxidation of 2-benzylpyridine (312) using air as the oxidant.
Scheme 76: Continuous-flow photo-oxygenation of monoterpenes.
Scheme 77: A tubular reactor design for flow photo-oxygenation.
Scheme 78: Glucose oxidase (GOx)-mediated continuous oxidation of glucose using compressed air and the FFMR re...
Scheme 79: Schematic continuous-flow sodium hypochlorite/TEMPO oxidation of alcohols.
Scheme 80: Oxidation using immobilised TEMPO (344) was developed by McQuade et al.
Scheme 81: General protocol for the bleach/catalytic TBAB oxidation of aldehydes and alcohols.
Scheme 82: Continuous-flow PTC-assisted oxidation using hydrogen peroxide. The process was easily scaled up by...
Scheme 83: Continuous-flow epoxidation of cyclohexene (348) and in situ preparation of m-CPBA.
Scheme 84: Continuous-flow epoxidation using DMDO as oxidant.
Scheme 85: Mukayama aerobic epoxidation optimised in flow mode by the Favre-Réguillon group.
Scheme 86: Continuous-flow asymmetric epoxidation of derivatives of 359 exploiting a biomimetic iron catalyst.
Scheme 87: Continuous-flow enzymatic epoxidation of alkenes developed by Watts et al.
Scheme 88: Engineered multichannel microreactor for continuous-flow ozonolysis of 366.
Scheme 89: Continuous-flow synthesis of the vitamin D precursor 368 using multichannel microreactors. MFC: mas...
Scheme 90: Continuous ozonolysis setup used by Kappe et al. for the synthesis of various substrates employing ...
Scheme 91: Continuous-flow apparatus for ozonolysis as developed by Ley et al.
Scheme 92: Continuous-flow ozonolysis for synthesis of vanillin (2) using a film-shear flow reactor.
Scheme 93: Examples of preparative methods for ajoene (386) and allicin (388).
Scheme 94: Continuous-flow oxidation of thioanisole (389) using styrene-based polymer-supported peroxytungstat...
Scheme 95: Continuous oxidation of thiosulfinates using Oxone®-packed reactor.
Scheme 96: Continuous-flow electrochemical oxidation of thioethers.
Scheme 97: Continuous-flow oxidation of 400 to cinnamophenone (235).
Scheme 98: Continuous-flow synthesis of dehydrated material 401 via oxidation of methyl dihydrojasmonate (33).
Scheme 99: Some industrially important transformations involving Grignard reagents.
Scheme 100: Grachev et al. apparatus for continuous preparation of Grignard reagents.
Scheme 101: Example of fluidized Mg bed reactor with NMR spectrometer as on-line monitoring system.
Scheme 102: Continuous-flow synthesis of Grignard reagents and subsequent quenching reaction.
Figure 10: Membrane-based, liquid–liquid separator with integrated pressure control [52]. Adapted with permission ...
Scheme 103: Continuous-flow synthesis of 458, an intermediate to fluconazole (459).
Scheme 104: Continuous-flow synthesis of ketones starting from benzoyl chlorides.
Scheme 105: A Grignard alkylation combining CSTR and PFR technologies with in-line infrared reaction monitoring....
Scheme 106: Continuous-flow preparation of 469 from Grignard addition of methylmagnesium bromide.
Scheme 107: Continuous-flow synthesis of Grignard reagents 471.
Scheme 108: Preparation of the Grignard reagent 471 using CSTR and the continuous process for synthesis of the ...
Scheme 109: Continuous process for carboxylation of Grignard reagents in flow using tube-in-tube technology.
Scheme 110: Continuous synthesis of propargylic alcohols via ethynyl-Grignard reagent.
Scheme 111: Silica-supported catalysed enantioselective arylation of aldehydes using Grignard reagents in flow ...
Scheme 112: Acid-catalysed rearrangement of citral and dehydrolinalool derivatives.
Scheme 113: Continuous stilbene isomerisation with continuous recycling of photoredox catalyst.
Scheme 114: Continuous-flow synthesis of compound 494 as developed by Ley et al.
Scheme 115: Selected industrial applications of DA reaction.
Scheme 116: Multistep flow synthesis of the spirocyclic structure 505 via employing DA cycloaddition.
Scheme 117: Continuous-flow DA reaction developed in a plater flow reactor for the preparation of the adduct 508...
Scheme 118: Continuous-flow DA reaction using a silica-supported imidazolidinone organocatalyst.
Scheme 119: Batch vs flow for the DA reaction of (cyclohexa-1,5-dien-1-yloxy)trimethylsilane (513) with acrylon...
Scheme 120: Continuous-flow DA reaction between 510 and 515 using a shell-core droplet system.
Scheme 121: Continuous-flow synthesis of bicyclic systems from benzyne precursors.
Scheme 122: Continuous-flow synthesis of bicyclic scaffolds 527 and 528 for further development of potential ph...
Scheme 123: Continuous-flow inverse-electron hetero-DA reaction to pyridine derivatives such as 531.
Scheme 124: Comparison between batch and flow for the synthesis of pyrimidinones 532–536 via retro-DA reaction ...
Scheme 125: Continuous-flow coupled with ultrasonic system for preparation of ʟ-ascorbic acid derivatives 539 d...
Scheme 126: Two-step continuous-flow synthesis of triazole 543.
Scheme 127: Continuous-flow preparation of triazoles via CuAAC employing 546-based heterogeneous catalyst.
Scheme 128: Continuous-flow synthesis of compounds 558 through A3-coupling and 560 via AgAAC both employing the...
Scheme 129: Continuous-flow photoinduced [2 + 2] cycloaddition for the preparation of bicyclic derivatives of 5...
Scheme 130: Continuous-flow [2 + 2] and [5 + 2] cycloaddition on large scale employing a flow reactor developed...
Scheme 131: Continuous-flow preparation of the tricyclic structures 573 and 574 starting from pyrrole 570 via [...
Scheme 132: Continuous-flow [2 + 2] photocyclization of cinnamates.
Scheme 133: Continuous-flow preparation of cyclobutane 580 on a 5-plates photoreactor.
Scheme 134: Continuous-flow [2 + 2] photocycloaddition under white LED lamp using heterogeneous PCN as photocat...
Figure 11: Picture of the parallel tube flow reactor (PTFR) "The Firefly" developed by Booker-Milburn et al. a...
Scheme 135: Continuous-flow acid-catalysed [2 + 2] cycloaddition between silyl enol ethers and acrylic esters.
Scheme 136: Continuous synthesis of lactam 602 using glass column reactors.
Scheme 137: In situ generation of ketenes for the Staudinger lactam synthesis developed by Ley and Hafner.
Scheme 138: Application of [2 + 2 + 2] cycloadditions in flow employed by Ley et al.
Scheme 139: Examples of FC reactions applied in F&F industry.
Scheme 140: Continuous-flow synthesis of ibuprofen developed by McQuade et al.
Scheme 141: The FC acylation step of Jamison’s three-step ibuprofen synthesis.
Scheme 142: Synthesis of naphthalene derivative 629 via FC acylation in microreactors.
Scheme 143: Flow system for rapid screening of catalysts and reaction conditions developed by Weber et al.
Scheme 144: Continuous-flow system developed by Buorne, Muller et al. for DSD optimisation of the FC acylation ...
Scheme 145: Continuous-flow FC acylation of alkynes to yield β-chlorovinyl ketones such as 638.
Scheme 146: Continuous-flow synthesis of tonalide (619) developed by Wang et al.
Scheme 147: Continuous-flow preparation of acylated arene such as 290 employing Zr4+-β-zeolite developed by Kob...
Scheme 148: Flow system applied on an Aza-FC reaction catalysed by the thiourea catalyst 648.
Scheme 149: Continuous hydroformylation in scCO2.
Scheme 150: Two-step flow synthesis of aldehyde 655 through a sequential Heck reaction and subsequent hydroform...
Scheme 151: Single-droplet (above) and continuous (below) flow reactors developed by Abolhasani et al. for the ...
Scheme 152: Continuous hydroformylation of 1-dodecene (655) using a PFR-CSTR system developed by Sundmacher et ...
Scheme 153: Continuous-flow synthesis of the aldehyde 660 developed by Eli Lilly & Co. [32]. Adapted with permissio...
Scheme 154: Continuous asymmetric hydroformylation employing heterogenous catalst supported on carbon-based sup...
Scheme 155: Examples of acetylation in F&F industry: synthesis of bornyl (S,R,S-664) and isobornyl (S,S,S-664) ...
Scheme 156: Continuous-flow preparation of bornyl acetate (S,R,S-664) employing the oscillating flow reactor.
Scheme 157: Continuous-flow synthesis of geranyl acetate (666) from acetylation of geraniol (343) developed by ...
Scheme 158: 12-Ttungstosilicic acid-supported silica monolith-catalysed acetylation in flow.
Scheme 159: Continuous-flow preparation of cyclopentenone 676.
Scheme 160: Two-stage synthesis of coumarin (90) via acetylation of salicylaldehyde (88).
Scheme 161: Intensification process for acetylation of 5-methoxytryptamine (677) to melatonin (678) developed b...
Scheme 162: Examples of macrocyclic musky odorants both natural (679–681) and synthetic (682 and 683).
Scheme 163: Flow setup combined with microwave for the synthesis of macrocycle 686 via RCM.
Scheme 164: Continuous synthesis of 2,5-dihydro-1H-pyrroles via ring-closing metathesis.
Scheme 165: Continuous-flow metathesis of 485 developed by Leadbeater et al.
Figure 12: Comparison between RCM performed using different routes for the preparation of 696. On the left the...
Scheme 166: Continuous-flow RCM of 697 employed the solid-supported catalyst 698 developed by Grela, Kirschning...
Scheme 167: Continuous-flow RORCM of cyclooctene employing the silica-absorbed catalyst 700.
Scheme 168: Continuous-flow self-metathesis of methyl oleate (703) employing SILP catalyst 704.
Scheme 169: Flow apparatus for the RCM of 697 using a nanofiltration membrane for the recovery and reuse of the...
Scheme 170: Comparison of loadings between RCMs performed with different routes for the synthesis of 709.
Synthesis of multiply fluorinated N-acetyl-D-glucosamine and D-galactosamine analogs via the corresponding deoxyfluorinated glucosazide and galactosazide phenyl thioglycosides
- Vojtěch Hamala,
- Lucie Červenková Šťastná,
- Martin Kurfiřt,
- Petra Cuřínová,
- Martin Dračínský and
- Jindřich Karban
Beilstein J. Org. Chem. 2021, 17, 1086–1095, doi:10.3762/bjoc.17.85
- synthesis of unprotected multiply-deoxyfluorinated monosaccharides, including a complete series of mono-, di-, and trifluorinated ᴅ-glucose [15], difluorinated [20] and tetrafluorinated [13] ᴅ-galactose, and 2,3,4-trifluoro analogs of ᴅ-mannose, ᴅ-galactose, ᴅ-allose, ᴅ-talose, and ᴅ-altrose [13][21
Graphical Abstract
Scheme 1: Retrosynthetic analysis of the target fluoro analogs.
Scheme 2: Conversion of 1,6-anhydro derivatives into thioglycosides, and a possible mechanism for the formati...
Scheme 3: Deoxyfluorination and O-benzylation of thioglycosides and thioaglycone migration.
Scheme 4: Thioglycoside hydrolysis.
Scheme 5: Synthesis of the target compounds by azide/acetamide conversion and debenzylation.
Synthetic accesses to biguanide compounds
- Oleksandr Grytsai,
- Cyril Ronco and
- Rachid Benhida
Beilstein J. Org. Chem. 2021, 17, 1001–1040, doi:10.3762/bjoc.17.82
Graphical Abstract
Figure 1: Tautomeric forms of biguanide.
Figure 2: Illustrations of neutral, monoprotonated, and diprotonated structures biguanide.
Figure 3: The main approaches for the synthesis of biguanides. The core structure is obtained via the additio...
Scheme 1: The three main preparations of biguanides from cyanoguanidine.
Scheme 2: Synthesis of butylbiguanide using CuCl2 [16].
Scheme 3: Synthesis of biguanides by the direct fusion of cyanoguanidine and amine hydrochlorides [17,18].
Scheme 4: Synthesis of ethylbiguanide and phenylbiguanide as reported by Smolka and Friedreich [14].
Scheme 5: Synthesis of arylbiguanides through the reaction of cyanoguanidine with anilines in water [19].
Scheme 6: Synthesis of aryl- and alkylbiguanides by adaptations of Cohn’s procedure [20,21].
Scheme 7: Microwave-assisted synthesis of N1-aryl and -dialkylbiguanides [22,23].
Scheme 8: Synthesis of aryl- and alkylbiguanides by trimethylsilyl activation [24,26].
Scheme 9: Synthesis of phenformin analogs by TMSOTf activation [27].
Scheme 10: Synthesis of N1-(1,2,4-triazolyl)biguanides [28].
Scheme 11: Synthesis of 2-guanidinobenzazoles by addition of ortho-substituted anilines to cyanoguanidine [30,32] and...
Scheme 12: Synthesis of 2,4-diaminoquinazolines by the addition of 2-cyanoaniline to cyanoguanidine and from 3...
Scheme 13: Reactions of anthranilic acid and 2-mercaptobenzoic acid with cyanoguanidine [24,36,37].
Scheme 14: Synthesis of disubstituted biguanides with Cu(II) salts [38].
Scheme 15: Synthesis of an N1,N2,N5-trisubstituted biguanide by fusion of an amine hydrochloride and 2-cyano-1...
Scheme 16: Synthesis of N1,N5-disubstituted biguanides by the addition of anilines to cyanoguanidine derivativ...
Scheme 17: Microwave-assisted additions of piperazine and aniline hydrochloride to substituted cyanoguanidines ...
Scheme 18: Synthesis of N1,N5-alkyl-substituted biguanides by TMSOTf activation [27].
Scheme 19: Additions of oxoamines hydrochlorides to dimethylcyanoguanidine [49].
Scheme 20: Unexpected cyclization of pyridylcyanoguanidines under acidic conditions [50].
Scheme 21: Example of industrial synthesis of chlorhexidine [51].
Scheme 22: Synthesis of symmetrical N1,N5-diarylbiguanides from sodium dicyanamide [52,53].
Scheme 23: Synthesis of symmetrical N1,N5-dialkylbiguanides from sodium dicyanamide [54-56].
Scheme 24: Stepwise synthesis of unsymmetrical N1,N5-trisubstituted biguanides from sodium dicyanamide [57].
Scheme 25: Examples for the synthesis of unsymmetrical biguanides [58].
Scheme 26: Examples for the synthesis of an 1,3-diaminobenzoquinazoline derivative by the SEAr cyclization of ...
Scheme 27: Major isomers formed by the SEAr cyclization of symmetric biguanides derived from 2- and 3-aminophe...
Scheme 28: Lewis acid-catalyzed synthesis of 8H-pyrrolo[3,2-g]quinazoline-2,4-diamine [63].
Scheme 29: Synthesis of [1,2,4]oxadiazoles by the addition of hydroxylamine to dicyanamide [49,64].
Scheme 30: Principle of “bisamidine transfer” and analogy between the reactions with N-amidinopyrazole and N-a...
Scheme 31: Representative syntheses of N-amidino-amidinopyrazole hydrochloride [68,69].
Scheme 32: First examples of biguanide syntheses using N-amidino-amidinopyrazole [66].
Scheme 33: Example of “biguanidylation” of a hydrazide substrate [70].
Scheme 34: Example for the synthesis of biguanides using S-methylguanylisothiouronium iodide as “bisamidine tr...
Scheme 35: Synthesis of N-substituted N1-cyano-S-methylisothiourea precursors.
Scheme 36: Addition routes on N1-cyano-S-methylisothioureas.
Scheme 37: Synthesis of an hydroxybiguanidine from N1-cyano-S-methylisothiourea [77].
Scheme 38: Synthesis of an N1,N2,N3,N4,N5-pentaarylbiguanide from the corresponding triarylguanidine and carbo...
Scheme 39: Reactions of N,N,N’,N’-tetramethylguanidine (TMG) with carbodiimides to synthesize hexasubstituted ...
Scheme 40: Microwave-assisted addition of N,N,N’,N’-tetramethylguanidine to carbodiimides [80].
Scheme 41: Synthesis of N1-aryl heptasubstituted biguanides via a one-pot biguanide formation–copper-catalyzed ...
Scheme 42: Formation of 1,2-dihydro-1,3,5-triazine derivatives by the reaction of guanidine with excess carbod...
Scheme 43: Plausible mechanism for the spontaneous cyclization of triguanides [82].
Scheme 44: a) Formation of mono- and disubstituted (iso)melamine derivatives by the reaction of biguanides and...
Scheme 45: Reactions of 2-aminopyrimidine with carbodiimides to synthesize 2-guanidinopyrimidines as “biguanid...
Scheme 46: Non-catalyzed alternatives for the addition of 2-aminopyrimidine derivatives to carbodiimides. A) h...
Scheme 47: Addition of guanidinomagnesium halides to substituted cyanamides [90].
Scheme 48: Microwave-assisted synthesis of [11C]metformin by the reaction of 11C-labelled dimethylcyanamide an...
Scheme 49: Formation of 4-amino-6-dimethylamino[1,3,5]triazin-2-ol through the reaction of Boc-guanidine and d...
Scheme 50: Formation of 1,3,5-triazine derivatives via the addition of guanidines to substituted cyanamides [92].
Scheme 51: Synthesis of biguanide by the reaction of O-alkylisourea and guanidine [93].
Scheme 52: Aromatic nucleophilic substitution of guanidine on 2-O-ethyl-1,3,5-triazine [95].
Scheme 53: Synthesis of N1,N2-disubstituted biguanides by the reaction of guanidine and thioureas in the prese...
Scheme 54: Cyclization reactions involving condensations of guanidine(-like) structures with thioureas [97,98].
Scheme 55: Condensations of guanidine-like structures with thioureas [99,100].
Scheme 56: Condensations of guanidines with S-methylisothioureas [101,102].
Scheme 57: Addition of 2-amino-1,3-diazaaromatics to S-alkylisothioureas [103,104].
Scheme 58: Addition of guanidines to 2-(methylsulfonyl)pyrimidines [105].
Scheme 59: An example of a cyclodesulfurization reaction to a fused 3,5-diamino-1,2,4-triazole [106].
Scheme 60: Ring-opening reactions of 1,3-diaryl-2,4-bis(arylimino)-1,3-diazetidines [107].
Scheme 61: Formation of 3,5-diamino-1,2,4-triazole derivatives via addition of hydrazines to 1,3-diazetidine-2...
Scheme 62: Formation of a biguanide via the addition of aniline to 1,2,4-thiadiazol-3,5-diamines, ring opening...
Figure 4: Substitution pattern of biguanides accessible by synthetic pathways a–h.
Metal-free glycosylation with glycosyl fluorides in liquid SO2
- Krista Gulbe,
- Jevgeņija Lugiņina,
- Edijs Jansons,
- Artis Kinens and
- Māris Turks
Beilstein J. Org. Chem. 2021, 17, 964–976, doi:10.3762/bjoc.17.78
- armed and disarmed glucose and mannose-derived glycosyl fluorides in moderate to excellent yields. A series of pivaloyl-protected O- and S-mannosides, as well as one example of a C-mannoside, are synthesized to demonstrate the scope of the glycosyl acceptors. The formation of the fluorosulfite species
- through the neighboring ester type protecting group assistance. At lower temperatures the glycosylation yield was lower, although full conversion of glucosyl fluoride β-9 was still observed. Compared to the analogue mannose derivative α-1a, glucose β-9 turned out to be less stable and more prone to
- conclusion that the Lewis basic carbonyl oxygen of the acetyl group is more coordinated and less nucleophilic in liquid SO2 than the carbonyl oxygen of the pivaloyl group. The profile of side-products in this glucose series was similar to that observed for fluoride β-9 (see Supporting Information File 1
Graphical Abstract
Scheme 1: Scope of glycosyl acceptors for glycosylation with pivaloyl-protected mannosyl fluoride α-1a in liq...
Scheme 2: Glycosylation of binucleophiles 7a,b in liquid SO2.
Scheme 3: Pivaloyl-protected glucosyl fluoride β-9 as a glycosyl donor in liquid SO2.
Scheme 4: Benzyl protected manno- and glucopyranosyl fluorides α-15 and 16 as glycosyl donors in liquid SO2. ...
Scheme 5: 2-Deoxy glycosyl fluoride α-19 as a glycosyl donor in liquid SO2.
Figure 1: Detection of the FSO2− species by 19F NMR (471 MHz, D2O).
Figure 2: Computational study of reaction mechanism α-11 + MeOH → α-13c in the presence of and in absence of ...
Simulating the enzymes of ganglioside biosynthesis with Glycologue
- Andrew G. McDonald and
- Gavin P. Davey
Beilstein J. Org. Chem. 2021, 17, 739–748, doi:10.3762/bjoc.17.64
- linear chain comprising of up to four monosaccharide units, containing glucose, galactose and N-acetylgalactosamine, to which are attached a variable number of sialic acid (N-acetylneuraminic acid) residues. The sialic acid content of the oligosaccharide, being anionic at pH 7, results in an overall
- since been rescinded [21].) To this base string are added a list of the sialic acids attached to each monosaccharide in the core, counting using the Roman numeral system, starting from the base glucose (cf. Figure 1). From the non-reducing end, write the position on the core where a sialic acid (or
- extended with a galactose, β4-linked to the glucose, to form lactosylceramide, LacCer, catalyzed by β4Gal-T6 (EC 2.4.1.274). This is the first asialo-ganglioside, with core level 3. Two further extensions are possible, to yield core levels 2 and 1, by adding a GalNAc residue β4-linked to the preceding
Graphical Abstract
Figure 1: Chemical structure of ganglioside GM1a (a β-ᴅ-galactosyl-(1→3)-N-acetyl-β-ᴅ-galactosaminyl-(1→4)-[α-...
Figure 2: Construction of the Svennerholm name GP1cα from its Glycologue structure identifier. At each step o...
Figure 3: Ganglioside carbohydrates predicted by the model. All structures are linked to ceramide at the base...
Figure 4: Ganglioside biosynthetic reaction network predicted by the Glycologue enzyme simulator. Starting fr...
Figure 5: Predicted effects on the pathways of ganglioside biosynthesis when individual enzyme activities are...
Valorisation of plastic waste via metal-catalysed depolymerisation
- Francesca Liguori,
- Carmen Moreno-Marrodán and
- Pierluigi Barbaro
Beilstein J. Org. Chem. 2021, 17, 589–621, doi:10.3762/bjoc.17.53
- monobutyltin oxide, using substoichiometric amounts of isosorbide and succinic acid and no solvent at 230 °C reaction temperature. Isosorbide is a safe chemical [246] that is obtainable on the large scale from renewable glucose [247][248]. Because of this and due to the inherent rigid structure, conferring the
Graphical Abstract
Figure 1: Potential classification of plastic recycling processes. The area covered by the present review is ...
Figure 2: EG produced during glycolytic depolymerisation of PET using DEG + DPG as solvent and titanium(IV) n...
Scheme 1: Simplified representation of the conversion of 1,4-PBD to C16–C44 macrocycles using Ru metathesis c...
Figure 3: Main added-value monomers obtainable by catalytic depolymerisation of PET via chemolytic methods.
Scheme 2: Hydrogenolytic depolymerisation of PET by ruthenium complexes.
Scheme 3: Depolymerisation of PET via catalytic hydrosilylation by Ir(III) pincer complex.
Scheme 4: Catalytic hydrolysis (top) and methanolysis (bottom) reactions of PET.
Scheme 5: Depolymerisation of PET by glycolysis with ethylene glycol.
Figure 4: Glycolysis of PET: evolution of BHET yield over time, with and without zinc acetate catalyst (196 °...
Scheme 6: Potential activated complex for the glycolysis reaction of PET catalysed by metallated ILs and evol...
Scheme 7: One-pot, two-step process for PET repurposing via chemical recycling.
Scheme 8: Synthetic routes to PLA.
Scheme 9: Structures of the zinc molecular catalysts used for PLA-methanolysis in various works. a) See [265], b) ...
Scheme 10: Depolymerisation of PLLA by Zn–N-heterocyclic carbene complex.
Scheme 11: Salalen ligands.
Scheme 12: Catalytic hydrogenolysis of PLA.
Scheme 13: Catalytic hydrosilylation of PLA.
Scheme 14: Hydrogenative depolymerisation of PBT and PCL by molecular Ru catalysts.
Scheme 15: Glycolysis reaction of PCT by diethylene glycol.
Scheme 16: Polymerisation–depolymerisation cycle of 3,4-T6GBL.
Scheme 17: Polymerisation–depolymerisation cycle of 2,3-HDB.
Scheme 18: Hydrogenative depolymerisation of PBPAC by molecular Ru catalysts.
Scheme 19: Catalytic hydrolysis (top), alcoholysis (middle) and aminolysis (bottom) reactions of PBPAC.
Scheme 20: Hydrogenative depolymerisation of PPC (top) and PEC (bottom) by molecular Ru catalysts.
Scheme 21: Polymerisation-depolymerisation cycle of BEP.
Scheme 22: Hydrogenolysis of polyamides using soluble Ru catalysts.
Scheme 23: Catalytic depolymerisation of epoxy resin/carbon fibres composite.
Scheme 24: Depolymerisation of polyethers with metal salt catalysts and acyl chlorides.
Scheme 25: Proposed mechanism for the iron-catalysed depolymerisation reaction of polyethers. Adapted with per...
Metal-free visible-light-enabled vicinal trifluoromethyl dithiolation of unactivated alkenes
- Xiaojuan Li,
- Qiang Zhang,
- Weigang Zhang,
- Jinzhu Ma,
- Yi Wang and
- Yi Pan
Beilstein J. Org. Chem. 2021, 17, 551–557, doi:10.3762/bjoc.17.49
- corresponding SCF3 adducts. In addition, boldenone- and ᴅ-glucose-derived terminal alkenes were compatible with the conditions affording the corresponding products 5l and 5m in moderate to good yields. To gain insight into the reaction mechanism, control experiments were conducted under the standard conditions
Graphical Abstract
Scheme 1: Origin of the reaction design.
Scheme 2: Substrate scope of disulfides.
Scheme 3: Substrate scope of unactivated alkenes.
Scheme 4: Control experiments.
Scheme 5: Proposed mechanism.
Identification of volatiles from six marine Celeribacter strains
- Anuj Kumar Chhalodia,
- Jan Rinkel,
- Dorota Konvalinkova,
- Jörn Petersen and
- Jeroen S. Dickschat
Beilstein J. Org. Chem. 2021, 17, 420–430, doi:10.3762/bjoc.17.38
- incorporation was observed for the other two sulfur atoms of 41 prompted us to further investigate the biosynthetic origin of the benzothiazol-2-ylsulfanyl portion of 41 to establish its natural origin. Several feeding experiments with central primary metabolites including (13C6)glucose, (13C5)ribose and
Graphical Abstract
Scheme 1: Sulfur metabolism in bacteria from the roseobacter group. A) DMSP demethylation by DmdABCD, B) DMSP...
Figure 1: Total ion chromatograms of headspace extracts from A) C. marinus DSM 100036T, B) C. neptunius DSM 2...
Figure 2: Structures of the identified volatile compounds in the headspace extracts from six Celeribacter typ...
Figure 3: EI mass spectra of A) unlabeled 2-(methyldisulfanyl)benzothiazole (41) and of labeled 41 after feed...
Scheme 2: Synthesis of sulfur-containing compounds detected in the Celeribacter headspace extracts. A) Synthe...
Regioselective chemoenzymatic syntheses of ferulate conjugates as chromogenic substrates for feruloyl esterases
- Olga Gherbovet,
- Fernando Ferreira,
- Apolline Clément,
- Mélanie Ragon,
- Julien Durand,
- Sophie Bozonnet,
- Michael J. O'Donohue and
- Régis Fauré
Beilstein J. Org. Chem. 2021, 17, 325–333, doi:10.3762/bjoc.17.30
- /L ammonium chloride, 20 mL/L oleic acid, 10 g/L ᴅ-glucose, 2 g/L casamino acid, and 15 g/L bacto agar in 100 mM citrate–phosphate buffer at pH 5). The petri dishes were incubated for 48 h at 30 °C and then overlayered with a preparation of 1% (w/v) molten top agar containing the chromogenic
Graphical Abstract
Figure 1: Alternative syntheses (A) and full structures (B) of the 5-bromo-4-chloro-3-indolyl or 4-nitropheny...
Scheme 1: Chemoenzymatic synthesis of (±)-4-O-(2-hydroxy-4-nitrophenyl)-1-O-trans-feruloyl-1,2,4-butanetriol ...
Figure 2: (A) Spectrometric monitoring (at 530 nm) of 4NTC released after the action of Fae on 12 in the pres...
Direct synthesis of anomeric tetrazolyl iminosugars from sugar-derived lactams
- Michał M. Więcław and
- Bartłomiej Furman
Beilstein J. Org. Chem. 2021, 17, 115–123, doi:10.3762/bjoc.17.12
- iminosugar derivatives may be less obvious. Several pharmaceuticals are based on this scaffold including the glucose-derived nojirimycin, an antibiotic and glycosidase inhibitor [26] and 1-deoxygalactonojirimycin, known under the trade name Galafold®, which is utilized for the treatment of the Fabry disease
- standard Ugi–azide reaction conditions [35][36][37][38][39] in a one-pot, tandem process. Subjecting glucose-derived lactam 1 to such a procedure gave the desired product in good yield, but with virtually no diastereoselectivity, as shown in Scheme 2. Optimization and scope An initial optimization study
- conformer. Therefore, once the ground conformer of the oxocarbenium ion is established, this logic may be used to predict the reaction’s stereochemistry. The same principle may be successfully applied to reactions of iminium cations. We have previously shown that in the case of glucose- and galactose
Graphical Abstract
Scheme 1: Our previous efforts in the field of functionalization of sugar-derived lactams.
Figure 1: Key concepts behind the goal of this work [34].
Scheme 2: Preliminary experiment in search of a procedure for the synthesis of 2-(1H-tetrazol-5-yl)-iminosuga...
Scheme 3: Synthesis of a new class of alkaloid scaffold using the presented methodology.
Scheme 4: Synthesis of a new, chiral 2-(tetrazol-5-yl)-iminosugar based potential organocatalyst.
Scheme 5: Principle behind Woerpel’s model for prediction of the direction of nucleophile addition to oxocarb...
Scheme 6: Difference in conformational stability of glucose- and galactose-derived iminium cations and the maj...
Figure 2: ORTEP structures of compounds 3a and 3e obtained by X-ray analysis. Hydrogen atoms and benzyl group...
Figure 3: Proposed structures of compounds 5a and 2-epi-5a with 1H-1H couplings and NOE effects shown.
Scheme 7: Proposed reaction mechanism for the described Ugi–azide reaction variant.
Scheme 8: Possible pathway for spontaneous imine formation. Values reported are in kcal·mol−1.
Scheme 9: A possible path for tetrazole formation in the described conditions. Values reported are in kcal·mol...
Semiautomated glycoproteomics data analysis workflow for maximized glycopeptide identification and reliable quantification
- Steffen Lippold,
- Arnoud H. de Ru,
- Jan Nouta,
- Peter A. van Veelen,
- Magnus Palmblad,
- Manfred Wuhrer and
- Noortje de Haan
Beilstein J. Org. Chem. 2020, 16, 3038–3051, doi:10.3762/bjoc.16.253
- -glycans are attached to Ser or Thr. Glycan compositions can range from monosaccharides (e.g., Tn antigen for O-glycans [1]) to large polysaccharides (e.g., N-glycans of recombinant human erythropoietin [2]). The most common building blocks of human protein glycans are hexoses (glucose, galactose, and
Graphical Abstract
Figure 1: Integration of automated glycopeptide identification by Byonic and GlycopeptideGraphMS (aided by Op...
Figure 2: Representative IgG and IgA glycopeptide clusters detected by GlycopeptideGraphMS.
Figure 3: Representative GlycopeptideGraphMS output for peptides of interest. Assigned compositions were iden...
Figure 4: Comparison of quantification results obtained by manual integration of EICs in Skyline (black), aut...
Secondary metabolites of Bacillus subtilis impact the assembly of soil-derived semisynthetic bacterial communities
- Heiko T. Kiesewalter,
- Carlos N. Lozano-Andrade,
- Mikael L. Strube and
- Ákos T. Kovács
Beilstein J. Org. Chem. 2020, 16, 2983–2998, doi:10.3762/bjoc.16.248
- g⋅L−1 dipotassium hydrogen phosphate, and 2.5 g⋅L−1 glucose. Semisynthetic mock community assay Semisynthetic soil communities were obtained from the soil of sampling site P5 (55.788800, 12.558300) [51][64]. 1 g soil was mixed in a 1:9 ratio with a 0.9% saline solution, vortexed on a rotary shaker
Graphical Abstract
Figure 1: Overview of the NRPs surfactin, plipastatin, bacillibactin, and iturin as well as the hybrid NRP-PK...
Figure 2: Overview of the experimental setup. A soil suspension, obtained from a soil sample, was used as an ...
Figure 3: The taxonomic summaries are showing the relative abundance of the most abundant genera for each rep...
Figure 4: Diversity analyses of the soil sample (“Soil”), 12 h preincubated soil suspensions (“Pre”), and unt...
Figure 5: Abundance ratios for each genus and replicate (points) in the control community compared to the WT-...
Figure 6: The relative abundance of Lysinibacillus in the untreated (“Control”) and treated mock communities ...
Figure 7: Growth curves of L. fusiformis M5 exposed to spent media from 48 h B. subtilis cultures and without...
Figure 8: Growth curves of L. fusiformis M5 exposed to different concentrations of surfactin, the highest con...
Figure 9: Overview on the biosynthetic pathways of surfactin (A), plipastatin (B), and bacillaene (C) produce...
Selected peptide-based fluorescent probes for biological applications
- Debabrata Maity
Beilstein J. Org. Chem. 2020, 16, 2971–2982, doi:10.3762/bjoc.16.247
- serum albumin. Other biomolecules such as adenosine, adenosine monophosphate, adenosine triphosphate, phosphate, pyrophosphate, glucose, heparin, hyaluronic acid and chondroitin sulfate, and amino acids containing two carboxylates (glutamic acid and aspartic acid) have not increased the fluorescence
- biological analytes including such as adenosine, adenosine monophosphate (AMP), adenosine triphosphates (ATP), phosphate (Pi), pyrophosphate (PPi), ct-DNA, glucose, bovine serum albumin (BSA), glutamic acid and aspartic acid. They are also selective over the similar biological analytes hyaluronic acid or
Graphical Abstract
Figure 1: Three different type of peptide-based fluorescent probes and their interaction with nucleic acids a...
Figure 2: A) Molecular structure of peptidic probe 1, Inset: HeLa cells incubated with peptide 1 (50 μM), sho...
Figure 3: A) Molecular structure of probe 2; B) fluorescence emission spectra for the titration of a 10 μM so...
Figure 4: A) Molecular structure of 3; B) fluorescence emission spectra for the titration of a 10 μM solution...
Figure 5: A) Molecular structure of 4 and 5; B) fluorescence spectra for the titration of a 0.5 μM solution o...
Figure 6: A) Molecular structure of 6; B) possible binding mode of pyrene termini of 6 to CB[8] according to ...
Figure 7: A) Molecular structure of peptidic probes 7 and 8; B) fluorescence emission spectra of probe 7 (5.0...
Figure 8: Top: Molecular structure of 9; bottom: A) fluorescence response of 9 (500 nM) upon addition of β-tr...
Figure 9: Top: Molecular structures of 10 and 11; bottom: A) fluorescence emission spectra of 10 (1.0 µM, λex...
Figure 10: A) Structure of two peptide amphiphiles 12 and 13; B) fluorescent spectra (λex = 400 nm) from a tit...
Figure 11: a) Molecular structure of peptide 14; b) the coordinate represents the states of sensor at differen...
