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Search for "benzoic acid" in Full Text gives 163 result(s) in Beilstein Journal of Organic Chemistry.
Aromatic and heterocyclic perfluoroalkyl sulfides. Methods of preparation
- Vladimir N. Boiko
Beilstein J. Org. Chem. 2010, 6, 880–921, doi:10.3762/bjoc.6.88
- and form 1,3-bis(SCF3) benzene [38][39][40] and 4-SCF3-benzoic acid fluoride, respectively [55]. The use of hydrogen fluoride has some advantages. Due to its low boiling point (+19.4 °C) and good solubility in water, excess HF is easily removed from the reaction mixture. Unlike HF, reactions with SbF3
Graphical Abstract
Figure 1: Examples of industrial fluorine-containing bio-active molecules.
Figure 2: CF3(S)- and CF3(O)-containing pharmacologically active compounds.
Figure 3: Hypotensive candidates with SRF and SO2RF groups – analogues of Losartan and Nifedipin.
Figure 4: The variety of the pharmacological activity of RFS-substituted compounds.
Figure 5: Recent examples of compounds containing RFS(O)n-groups [12-18].
Scheme 1: Fluorination of ArSCCl3 to corresponding ArSCF3 derivatives. For references see: a[38-43]; b[41,42]; c[43]; d[44]; e[38-43,45-47]; f[38-43,48,49]; g...
Scheme 2: Preparation of aryl pentafluoroethyl sulfides.
Scheme 3: Mild fluorination of the aryl SCF2Br derivatives.
Scheme 4: HF fluorinations of aryl α,α,β-trichloroisobutyl sulfide at various conditions.
Scheme 5: Monofluorination of α,α-dichloromethylene group.
Scheme 6: Electrophilic substitution of phenols with CF3SCl [69].
Scheme 7: Introduction of SCF3 groups into activated phenols [71-74].
Scheme 8: Preparation of tetrakis(SCF3)-4-methoxyphenol [72].
Scheme 9: The interactions of resorcinol and phloroglucinol derivatives with RFSCl.
Scheme 10: Reactions of anilines with CF3SCl.
Scheme 11: Trifluoromethylsulfanylation of anilines with electron-donating groups in the meta position [74].
Scheme 12: Reaction of benzene with CF3SCl/CF3SO3H [77].
Scheme 13: Reactions of trifluoromethyl sulfenyl chloride with aryl magnesium and -mercury substrates.
Scheme 14: Reactions of pyrroles with CF3SCl.
Scheme 15: Trifluoromethylsulfanylation of indole and indolizines.
Scheme 16: Reactions of N-methylpyrrole with CF3SCl [80,82].
Scheme 17: Reactions of furan, thiophene and selenophene with CF3SCl.
Scheme 18: Trifluoromethylsulfanylation of imidazole and thiazole derivatives [83].
Scheme 19: Trifluoromethylsulfanylation of pyridine requires initial hydride reduction.
Scheme 20: Introduction of additional RFS-groups into heterocyclic compounds in the presence of CF3SO3H.
Scheme 21: Introduction of additional RFS-groups into pyrroles [82,87].
Scheme 22: By-products in reactions of pyrroles with CF3SCl [82].
Scheme 23: Reaction of aromatic iodides with CuSCF3 [93,95].
Scheme 24: Reaction of aromatic iodides with RFZCu (Z = S, Se), RF = CF3, C6F5 [93,95,96].
Scheme 25: Side reactions during trifluoromethylsulfanylation of aromatic iodides with CF3SCu [98].
Scheme 26: Reactions with in situ generated CuSCF3.
Scheme 27: Perfluoroalkylthiolation of aryl iodides with bulky RFSCu [105].
Scheme 28: In situ formation and reaction of RFZCu with aryl iodides.
Figure 6: Examples of compounds obtained using in situ generated RFZCu methodology [94].
Scheme 29: Introduction of SCF3 group into aromatics via difluorocarbene.
Scheme 30: Tetrakis(dimethylamino)ethylene dication trifluoromethyl thiolate as a stable reagent for substitut...
Scheme 31: The use of CF2=S/CsF or (CF3S)2C=S/CsF for the introduction of CF3S groups into fluorinated heteroc...
Scheme 32: One-pot synthesis of ArSCF3 from ArX, CCl2=S and KF.
Scheme 33: Reaction of aromatics with CF3S− Kat+ [115].
Scheme 34: Reactions of activated aromatic chlorides with AgSCF3/KI.
Scheme 35: Comparative CuSCF3/KI and Hg(SCF3)2/KI reactions.
Scheme 36: Me3SnTeCF3 – a reagent for the introduction of the TeCF3 group.
Scheme 37: Sandmeyer reactions with CuSCF3.
Scheme 38: Reactions of perfluoroalkyl iodides with alkali and organolithium reagents.
Scheme 39: Perfluoroalkylation with preliminary breaking of the disulfide bond.
Scheme 40: Preparation of RFS-substituted anilines from dinitrodiphenyl disulfides.
Scheme 41: Photochemical trifluoromethylation of 2,4,6-trimercaptochlorobenzene [163].
Scheme 42: Putative process for the formation of B, C and D.
Scheme 43: Trifluoromethylation of 2-mercapto-4-hydroxy-6-trifluoromethylyrimidine [145].
Scheme 44: Deactivation of 2-mercapto-4-hydroxypyrimidines S-centered radicals.
Scheme 45: Perfluoroalkylation of thiolates with CF3Br under UV irradiation.
Scheme 46: Catalytic effect of methylviologen for RF• generation.
Scheme 47: SO2−• catalyzed trifluoromethylation.
Scheme 48: Electrochemical reduction of CF3Br in the presence of SO2 [199,200].
Scheme 49: Participation of SO2 in the oxidation of ArSCF3−•.
Scheme 50: Electron transfer cascade involving SO2 and MV.
Scheme 51: Four stages of the SRN1 mechanism for thiol perfluoroalkylation.
Scheme 52: A double role of MV in the catalysis of RFI reactions with aryl thiols.
Scheme 53: Photochemical reaction of pentafluoroiodobenzene with trifluoromethyl disulfide.
Scheme 54: N- Trifluoromethyl-N-nitrosobenzene sulfonamide – a source of CF3• radicals [212,213].
Scheme 55: Radical trifluoromethylation of organic disulfides with ArSO2N=NCF3.
Scheme 56: Barton’s S-perfluoroalkylation reactions [216].
Scheme 57: Decarboxylation of thiohydroxamic esters in the presence of C6F13I.
Scheme 58: Reactions of thioesters of trifluoroacetic and trifluoromethanesulfonic acids in the presence of ar...
Scheme 59: Perfluoroalkylation of polychloropyridine thiols with xenon perfluorocarboxylates or XeF2 [222,223].
Scheme 60: Interaction of Xe(OCORF)2 with nitroaryl disulfide [227].
Scheme 61: Bi(CF3)3/Cu(OCOCH3)2 trifluoromethylation of thiophenolate [230].
Scheme 62: Reaction of fluorinated carbanions with aryl sulfenyl chlorides.
Scheme 63: Reaction of methyl perfluoromethacrylate with PhSCl in the presence of fluoride.
Scheme 64: Reactions of ArSCN with potassium and magnesium perfluorocarbanions [237].
Scheme 65: Reactions of RFI with TDAE and organic disulfides [239,240].
Scheme 66: Decarboxylation of perfluorocarboxylates in the presence of disulfides [245].
Scheme 67: Organization of a stable form of “CF3−” anion in the DMF.
Scheme 68: Silylated amines in the presence of fluoride can deprotonate fluoroform for reaction with disulfide...
Figure 7: Other examples of aminomethanols [264].
Scheme 69: Trifluoromethylation of diphenyl disulfide with PhSO2CF3/t-BuOK.
Scheme 70: Amides of trifluoromethane sulfinic acid are sources of CF3− anion.
Scheme 71: Trifluoromethylation of various thiols using “hyper-valent” iodine (III) reagent [279].
Scheme 72: Trifluoromethylation of p-nitrothiophenolate with diaryl CF3 sulfonium salts [280].
Scheme 73: Trifluoromethyl transfer from dibenzo (CF3)S-, (CF3)Se- and (CF3)Te-phenium salts to thiolates [283].
Scheme 74: Multi-stage paths for synthesis of dibenzo-CF3-thiophenium salts [61].
Pd-catalyzed decarboxylative Heck vinylation of 2-nitrobenzoates in the presence of CuF2
- Lukas J. Gooßen,
- Bettina Zimmermann and
- Thomas Knauber
Beilstein J. Org. Chem. 2010, 6, No. 43, doi:10.3762/bjoc.6.43
- yield 2-nitro-stilbene (3aa) as a model reaction, and investigated the catalytic activity of various combinations of palladium precursors, additives and oxidants (Table 1). The choice of an electron-deficient benzoic acid was motivated by our intention to overcome substrate limitations observed in Myers
Graphical Abstract
Scheme 1: Proposed mechanism for the decarboxylative Heck reaction.
Molecular recognition of organic ammonium ions in solution using synthetic receptors
- Andreas Späth and
- Burkhard König
Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32
Graphical Abstract
Figure 1: Biologically important amines and quaternary ammonium salts: histamine (1), dopamine (2) and acetyl...
Figure 2: Crown ether 18-crown-6.
Figure 3: Conformations of 18-crown-6 (4) in solvents of different polarity.
Figure 4: Binding topologies of the ammonium ion depending on the crown ring size.
Figure 5: A “pseudorotaxane” structure consisting of 24-crown-8 and a secondary ammonium ion (5); R = Ph.
Figure 6: Typical examples of azacrown ethers, cryptands and related aza macrocycles.
Figure 7: Binding of ammonium to azacrown ethers and cryptands [111-113].
Figure 8: A 19-crown-6-ether with decalino blocking groups (11) and a thiazole-dibenzo-18-crown-6-ether (12).
Figure 9: 1,3-Bis(6-oxopyridazin-1-yl)propane derivatives 13 and 14 by Campayo et al.
Figure 10: Fluorescent azacrown-PET-sensors based on coumarin.
Figure 11: Two different pyridino-cryptands (17 and 18) compared to a pyridino-crown (19); chiral ammonium ion...
Figure 12: Pyridino-18-crown-6 ligand (21), a similar acridino-18-crown-6 ligand (22) and a structurally relat...
Figure 13: Ciral pyridine-azacrown ether receptors 24.
Figure 14: Chiral 15-crown-5 receptors 26 and an analogue 18-crown-6 ligand 27 derived from amino alcohols.
Figure 15: C2-symmetric chiral 18-crown-6 amino alcohol derivatives 28 and related macrocycles.
Figure 16: Macrocycles with diamide-diester groups (30).
Figure 17: C2-symmetric chiral aza-18-crown-6 ethers (31) with phenethylamine residues.
Figure 18: Chiral C-pivot p-methoxy-phenoxy-lariat ethers.
Figure 19: Chiral lariat crown ether 34.
Figure 20: Sucrose-based chiral crown ether receptors 36.
Figure 21: Permethylated fructooligosaccharide 37 showing induced-fit chiral recognition.
Figure 22: Biphenanthryl-18-crown-6 derivative 38.
Figure 23: Chiral lariat crown ethers derived from binol by Fuji et al.
Figure 24: Chiral phenolic crown ether 41 with “aryl chiral barriers” and guest amines.
Figure 25: Chiral bis-crown receptor 43 with a meso-ternaphthalene backbone.
Figure 26: Chromogenic pH-dependent bis-crown chemosensor 44 for diamines.
Figure 27: Triamine guests for binding to receptor 44.
Figure 28: Chiral bis-crown phenolphthalein chemosensors 46.
Figure 29: Crown ether amino acid 47.
Figure 30: Luminescent receptor 48 for bis-alkylammonium guests.
Figure 31: Luminescent CEAA (49a), a bis-CEAA receptor for amino acids (49b) and the structure of lysine bindi...
Figure 32: Luminescent CEAA tripeptide for binding small peptides.
Figure 33: Bis crown ether 51a self assembles co-operatively with C60-ammonium ion 51b.
Figure 34: Triptycene-based macrotricyclic dibenzo-[24]-crown-8 ether host 52 and guests.
Figure 35: Copper imido diacetic acid azacrown receptor 53a and the suggested His-Lys binding motif; a copper ...
Figure 36: Urea (54) and thiourea (55) benzo crown receptor for transport and extraction of amino acids.
Figure 37: Crown pyryliums ion receptors 56 for amino acids.
Figure 38: Ditopic sulfonamide bridged crown ether receptor 57.
Figure 39: Luminescent peptide receptor 58.
Figure 40: Luminescent receptor 59 for the detection of D-glucosamine hydrochloride in water/ethanol and lumin...
Figure 41: Guanidinium azacrown receptor 61 for simple amino acids and ditopic receptor 62 with crown ether an...
Figure 42: Chiral bicyclic guanidinium azacrown receptor 63 and similar receptor 64 for the enantioselective t...
Figure 43: Receptors for zwitterionic species based on luminescent CEAAs.
Figure 44: 1,10-Azacrown ethers with sugar podand arms and the anticancer agent busulfan.
Figure 45: Benzo-18-crown-6 modified β-cyclodextrin 69 and β-cyclodextrin functionalized with diaza-18-crown-6...
Figure 46: Receptors for colorimetric detection of primary and secondary ammonium ions.
Figure 47: Porphyrine-crown-receptors 72.
Figure 48: Porphyrin-crown ether conjugate 73 and fullerene-ammonium ion guest 74.
Figure 49: Calix[4]arene (75a), homooxocalix[4]arene (75b) and resorcin[4]arene (75c) compared (R = H, alkyl c...
Figure 50: Calix[4]arene and ammonium ion guest (R = H, alkyl, OAcyl etc.), possible binding sites; A: co-ordi...
Figure 51: Typical guests for studies with calixarenes and related molecules.
Figure 52: Lower rim modified p-tert-butylcalix[5]arenes 82.
Figure 53: The first example of a water soluble calixarene.
Figure 54: Sulfonated water soluble calix[n]arenes that bind ammonium ions.
Figure 55: Displacement assay for acetylcholine (3) with a sulfonato-calix[6]arene (84b).
Figure 56: Amino acid inclusion in p-sulfonatocalix[4]arene (84a).
Figure 57: Calixarene receptor family 86 with upper and lower rim functionalization.
Figure 58: Calix[6]arenes 87 with one carboxylic acid functionality.
Figure 59: Sulfonated calix[n]arenes with mono-substitution at the lower rim systematically studied on their r...
Figure 60: Cyclotetrachromotropylene host (91) and its binding to lysine (81c).
Figure 61: Calixarenes 92 and 93 with phosphonic acids groups.
Figure 62: Calix[4]arene tetraphosphonic acid (94a) and a double bridged analogue (94b).
Figure 63: Calix[4]arene tetraphosphonic acid ester (92c) for surface recognition experiments.
Figure 64: Calixarene receptors 95 with α-aminophosphonate groups.
Figure 65: A bridged homocalix[3]arene 95 and a distally bridged homocalix[4]crown 96.
Figure 66: Homocalix[3]arene ammonium ion receptor 97a and the Reichardt’s dye (97b) for colorimetric assays.
Figure 67: Chromogenic diazo-bridged calix[4]arene 98.
Figure 68: Calixarene receptor 99 by Huang et al.
Figure 69: Calixarenes 100 reported by Parisi et al.
Figure 70: Guest molecules for inclusion in calixarenes 100: DAP × 2 HCl (101a), APA (101b) and Lys-OMe × 2 HC...
Figure 71: Different N-linked peptido-calixarenes open and with glycol chain bridges.
Figure 72: (S)-1,1′-Bi-2-naphthol calixarene derivative 104 published by Kubo et al.
Figure 73: A chiral ammonium-ion receptor 105 based on the calix[4]arene skeleton.
Figure 74: R-/S-phenylalaninol functionalized calix[6]arenes 106a and 106b.
Figure 75: Capped homocalix[3]arene ammonium ion receptor 107.
Figure 76: Two C3 symmetric capped calix[6]arenes 108 and 109.
Figure 77: Phosphorous-containing rigidified calix[6]arene 110.
Figure 78: Calix[6]azacryptand 111.
Figure 79: Further substituted calix[6]azacryptands 112.
Figure 80: Resorcin[4]arene (75c) and the cavitands (113).
Figure 81: Tetrasulfonatomethylcalix[4]resorcinarene (114).
Figure 82: Resorcin[4]arenes (115a/b) and pyrogallo[4]arenes (115c, 116).
Figure 83: Displacement assay for acetylcholine (3) with tetracyanoresorcin[4]arene (117).
Figure 84: Tetramethoxy resorcinarene mono-crown-5 (118).
Figure 85: Components of a resorcinarene based displacement assay for ammonium ions.
Figure 86: Chiral basket resorcin[4]arenas 121.
Figure 87: Resorcinarenes with deeper cavitand structure (122).
Figure 88: Resorcinarene with partially open deeper cavitand structure (123).
Figure 89: Water-stabilized deep cavitands with partially structure (124, 125).
Figure 90: Charged cavitands 126 for tetralkylammonium ions.
Figure 91: Ditopic calix[4]arene receptor 127 capped with glycol chains.
Figure 92: A calix[5]arene dimer for diammonium salt recognition.
Figure 93: Calixarene parts 92c and 129 for the formation molecular capsules.
Figure 94: Encapsulation of a quaternary ammonium cation by two resorcin[4]arene molecules (NMe4+@[75c]2 × Cl−...
Figure 95: Encapsulation of a quaternary ammonium cation by six resorcin[4]arene molecules (NMe3D+@[130]6 × Cl−...
Figure 96: Structure and schematic of cucurbit[6]uril (CB[6], 131a).
Figure 97: Cyclohexanocucurbit[6]uril (CB′[6], 132) and the guest molecule spermine (133).
Figure 98: α,α,δ,δ-Tetramethylcucurbit[6]uril (134).
Figure 99: Structure of the cucurbituril-phthalhydrazide analogue 135.
Figure 100: Organic cavities for the displacement assay for amine differentiation.
Figure 101: Displacement assay methodology for diammonium- and related guests involving cucurbiturils and some ...
Figure 102: Nor-seco-Cucurbituril (±)-bis-ns-CB[6] (140) and guest molecules.
Figure 103: The cucurbit[6]uril based complexes 141 for chiral discrimination.
Figure 104: Cucurbit[7]uril (131c) and its ferrocene guests (142) opposed.
Figure 105: Cucurbit[7]uril (131c) guest inclusion and representative guests.
Figure 106: Cucurbit[7]uril (131c) binding to succinylcholine (145) and different bis-ammonium and bis-phosphon...
Figure 107: Paraquat-cucurbit[8]uril complex 149.
Figure 108: Gluconuril-based ammonium receptors 150.
Figure 109: Examples of clefts (151a), tweezers (151b, 151c, 151d) and clips (151e).
Figure 110: Kemp’s triacid (152a), on example of Rebek’s receptors (152b) and guests.
Figure 111: Amino acid receptor (154) by Rebek et al.
Figure 112: Hexagonal lattice designed hosts by Bell et al.
Figure 113: Bell’s amidinium receptor (156) and the amidinium ion (157).
Figure 114: Aromatic phosphonic acids.
Figure 115: Xylene phosphonates 159 and 160a/b for recognition of amines and amino alcohols.
Figure 116: Bisphosphonate recognition motif 161 for a colorimetric assay with alizarin complexone (163) for ca...
Figure 117: Bisphosphonate/phosphate clip 164 and bisphosphonate cleft 165.
Figure 118: N-Methylpyrazine 166a, N-methylnicotinamide iodide (166b) and NAD+ (166c).
Figure 119: Bisphosphate cavitands.
Figure 120: Bisphosphonate 167 of Schrader and Finocchiaro.
Figure 121: Tweezer 168 for noradrenaline (80b).
Figure 122: Different tripods and heparin (170).
Figure 123: Squaramide based receptors 172.
Figure 124: Cage like NH4+ receptor 173 of Kim et al.
Figure 125: Ammonium receptors 174 of Chin et al.
Figure 126: 2-Oxazolin-based ammonium receptors 175a–d and 176 by Ahn et al.
Figure 127: Racemic guest molecules 177.
Figure 128: Tripods based on a imidazole containing macrocycle (178) and the guest molecules employed in the st...
Figure 129: Ammonium ion receptor 180.
Figure 130: Tetraoxa[3.3.3.3]paracyclophanes 181 and a cyclophanic tetraester (182).
Figure 131: Peptidic bridged paraquat-cyclophane.
Figure 132: Shape-selective noradrenaline host.
Figure 133: Receptor 185 for binding of noradrenaline on surface layers from Schrader et al.
Figure 134: Tetraphosphonate receptor for binding of noradrenaline.
Figure 135: Tetraphosphonate 187 of Schrader and Finocchiaro.
Figure 136: Zinc-Porphyrin ammonium-ion receptors 188 and 189 of Mizutani et al.
Figure 137: Zinc porphyrin receptor 190.
Figure 138: Zinc porphyrin receptors 191 capable of amino acid binding.
Figure 139: Zinc-porphyrins with amino acid side chains for stereoinduction.
Figure 140: Bis-zinc-bis-porphyrin based on Tröger’s base 193.
Figure 141: BINAP-zinc-prophyrin derivative 194 and it’s guests.
Figure 142: Bisaryl-linked-zinc-porphyrin receptors.
Figure 143: Bis-zinc-porphyrin 199 for diamine recognition and guests.
Figure 144: Bis-zinc-porphyrin crown ether 201.
Figure 145: Bis-zinc-porphyrin 202 for stereodiscrimination (L = large substituent; S = small substituent).
Figure 146: Bis-zinc-porphyrin[3]rotaxane and its copper complex and guests.
Figure 147: Dien-bipyridyl ligand 206 for co-ordination of two metal atoms.
Figure 148: The ligand and corresponding tetradentate co-complex 207 serving as enantioselective receptor for a...
Figure 149: Bis(oxazoline)–copper(II) complex 208 for the recognition of amino acids in aqueous solution.
Figure 150: Zinc-salen-complexes 209 for the recognition tertiary amines.
Figure 151: Bis(oxazoline)–copper(II) 211 for the recognition of amino acids in aqueous solution.
Figure 152: Zn(II)-complex of a C2 terpyridine crown ether.
Figure 153: Displacement assay and receptor for aspartate over glutamate.
Figure 154: Chiral complex 214 for a colorimetric displacement assay for amino acids.
Figure 155: Metal complex receptor 215 with tripeptide side arms.
Figure 156: A sandwich complex 216 and its displaceable dye 217.
Figure 157: Lanthanide complexes 218–220 for amino acid recognition.
Figure 158: Nonactin (221), valinomycin (222) and vancomycin (223).
Figure 159: Monesin (224a) and a chiral analogue for enantiodiscrimination of ammonium guests (224b).
Figure 160: Chiral podands (226) compared to pentaglyme-dimethylether (225) and 18-crown-6 (4).
Figure 161: Lasalocid A (228).
Figure 162: Lasalocid derivatives (230) of Sessler et al.
Figure 163: The Coporphyrin I tetraanion (231).
Figure 164: Linear and cyclic peptides for ammonium ion recognition.
Figure 165: Cyclic and bicyclic depsipeptides for ammonium ion recognition.
Figure 166: α-Cyclodextrin (136a) and novocaine (236).
Figure 167: Helical diol receptor 237 by Reetz and Sostmann.
Figure 168: Ammonium binding spherand by Cram et al. (238a) and the cyclic[6]metaphenylacetylene 238b in compar...
Figure 169: Receptor for peptide backbone and ammonium binding (239).
Figure 170: Anion sensor principle with 3-hydroxy-2-naphthanilide of Jiang et al.
Figure 171: 7-bromo-3-hydroxy-N-(2-hydroxyphenyl)naphthalene 2-carboxamide (241) and its amine binding.
Figure 172: Naturally occurring catechins with affinity to quaternary ammonium ions.
Figure 173: Spiropyran (244) and merocyanine form (244a) of the amino acid receptors of Fuji et al.
Figure 174: Coumarin aldehyde (245) and its iminium species with amino acid bound (245a) by Glass et al.
Figure 175: Coumarin aldehyde appended with boronic acid.
Figure 176: Quinolone aldehyde dimers by Glass et al.
Figure 177: Chromogenic ammonium ion receptors with trifluoroacetophenone recognition motifs.
Figure 178: Chromogenic ammonium ion receptor with trifluoroacetophenone recognition motif bound on different m...
Bioorthogonal metabolic glycoengineering of human larynx carcinoma (HEp-2) cells targeting sialic acid
- Arne Homann,
- Riaz-ul Qamar,
- Sevnur Serim,
- Petra Dersch and
- Jürgen Seibel
Beilstein J. Org. Chem. 2010, 6, No. 24, doi:10.3762/bjoc.6.24
- -functionalized carbohydrates in the glycocalyx are specifically addressed by complementary functionalized fluorescence agents 9-[2-carboxy-4-[(2-propyn-1-ylamino)carbonyl]phenyl]-3,6-bis(dimethylamino)xanthylium, alkynylated TAMRA or benzoic acid 2-[6-(3-azidopropanyloxy)-3-oxo-3H-xanthen-9-yl] 3-azidopropanyl
- [M-H]- calculated for C14H21NO9[H]- 360.13, found 360.2. Benzoic acid 2-[6-(3-azidopropanyloxy)-3-oxo-3H-xanthen-9-yl] 3-azidopropanyl ester, azido-fluorescein (14) Iodopropyl azide (210 mg, 26 mmol) was added to a solution of fluorescein (1g, 2.6mmol) in a mixture of distilled THF/MeOH (1:1, 25 mL
Graphical Abstract
Scheme 1: The natural forms of sialic acids, human N-acetylneuraminic acid (Neu5Ac, 1) and mammalian N-glycol...
Scheme 2: Synthesis of N-(1-oxohex-5-ynyl)neuraminic acid (Neu5Hex 3).
Scheme 3: Metabolic pathway of Ac4GlcNAz and the genetic control of Neu5Ac 1 synthesis by feedback inhibition...
Scheme 4: Proposed metabolic pathway of Neu5Hex 3 based on known mechanisms of Neu5Gc 2 uptake [5]. TGN: trans-G...
Scheme 5: Labelling of alkynylated neuraminic acid by azido-fluorescein.
Figure 1: Top left: HEp-2 cells incorporated with Ac4GlcNAz 16, labelled with alkynylated TAMRA at 580 nm. Bo...
Synthesis of lipophilic 1-deoxygalactonojirimycin derivatives as D-galactosidase inhibitors
- Georg Schitter,
- Elisabeth Scheucher,
- Andreas J. Steiner,
- Arnold E. Stütz,
- Martin Thonhofer,
- Chris A. Tarling,
- Stephen G. Withers,
- Jacqueline Wicki,
- Katrin Fantur,
- Eduard Paschke,
- Don J. Mahuran,
- Brigitte A. Rigat,
- Michael Tropak and
- Tanja M. Wrodnigg
Beilstein J. Org. Chem. 2010, 6, No. 21, doi:10.3762/bjoc.6.21
- desired free amine 15 [25], the key building block for further modifications (Scheme 2). The chemoselective acylation of the free amine 15 was conducted with three different benzoic acid derivatives in order to investigate the influence of the potential basicity of an additional nitrogen at the aromatic
Graphical Abstract
Figure 1: Typical representatives of iminosugars.
Figure 2: N-Modified iminosugars 5–9 as potential pharmacological chaperones.
Figure 3: Structure of NOEV 10.
Scheme 1: Three-step-synthesis of partially protected 1-deoxy-D-galactonojirimycin derivative 12 from 10 via ...
Scheme 2: Synthesis of N-(6-aminohexyl)-1-deoxygalactonojirimycin (15) from 12 via 14.
Scheme 3: Synthesis of lipophilic 1-deoxy-D-galactonojirimycin derivatives 16–18 by chemoselective acylation ...
Scheme 4: Synthesis of compounds 19 as well as 20 from primary amine 15.
Scheme 5: Synthesis of compound 22.
(Pseudo)amide-linked oligosaccharide mimetics: molecular recognition and supramolecular properties
- José L. Jiménez Blanco,
- Fernando Ortega-Caballero,
- Carmen Ortiz Mellet and
- José M. García Fernández
Beilstein J. Org. Chem. 2010, 6, No. 20, doi:10.3762/bjoc.6.20
- , Kessler and co-workers have reported the synthesis of cyclic oligomers containing glucopyranosyluronic acid by exploiting standard solid and solution phase coupling procedures [54]. These cyclic homo-oligomers of SAAs behave as host molecules that form inclusion complexes with p-nitrophenol and benzoic
- acid. Following the same objective, Xie’s group prepared orthogonally protected cyclic homo-oligomers with two to four SAA units that can be selectively or fully deprotected to afford macrocycles that can undergo further functionalisation (Figure 11) [55]. Conformational analysis by molecular modelling
Graphical Abstract
Figure 1: Schematic representation of sugar aminoacids (SAAs) and (pseudo)amide oligosaccharide mimetics.
Figure 2: Natural SAAs structures and natural nucleosidic antibiotics.
Scheme 1: Synthetic route to the target amide-linked sialooligomers. (a) Fmoc-Cl, NaHCO3, H2O, dioxane, 0 °C....
Figure 3: The general structure of glycoamino acids and their corresponding oligomers.
Figure 4: Conformational analysis of the β(1→2)-amide-linked glucooligomer 9.
Figure 5: Short oligomeric chains of C-glycosyl D-arabino THF amino acid oligomers.
Figure 6: (A) Stereoview of the minimized structure of compound 16 (produced by a 500 ps simulation) that mos...
Figure 7: Structures of linear oxetane-β- and δ-SAA homo-oligomers 19–20.
Figure 8: 10-Membered ring H-bonds in compound 21 consistent with NMR and modelling investigations.
Figure 9: General structure of carbopeptoid-oligonucleotide conjugates.
Figure 10: Protected derivatives of 2,6-diamino-2,6-dideoxy-β-D-glucopyranosyl carboxylic acid 22 and 23.
Figure 11: Cyclic homo-oligomers containing glucopyranoid-SAAs.
Scheme 2: Strategy for solid-phase synthesis of cyclic trimers and tetramers containing pyranoid δ-SAAs.
Figure 12: Cyclic tetramers of L-rhamno- and D-gulo-configured oxetane-SAAs.
Figure 13: Aminoglycosidic antibiotics of the glycocinnamoylspermidine family.
Scheme 3: Synthesis of (thio)trehazoline, via triflate, from β-hydroxy(thio)urea.
Figure 14: Approaches to access pseudoamide-type oligosaccharide mimics.
Figure 15: Calystegine B2 analogues 38 and 39 with urea-linked disaccharide structure.
Figure 16: Rotameric equilibrium shift of 40 by formation of a bidentate hydrogen bond.
Figure 17: Nucleotide analogues with thiourea and S-methylisothiouronium linkers.
Scheme 4: Retrosynthetic approach to synthesize thiourea-linked glycooligomers.
Figure 18: Rotameric equilibria for β-(1→6)-thiourea-linked glucodimer 41.
Figure 19: Schematic representation of (a) cyclodextrin (CDs) and (b) cyclotrehalan (CTs) family members.
Scheme 5: Synthesis of guanidine-linked pseudodisaccharides via carbodiimide.
Figure 20: β(1→6)-Guanidine-linked pseudodi- and pseudotrisaccharides 47 and 48.
Scheme 6: Synthesis of N-benzylguanidine-linked CT2 50.
Figure 21: Structure of RNG and DNG.
Figure 22: Preparation of Fmoc-guanidinium derivatives.
Figure 23: Structures of the homo-oligomeric RNG derivatives 51–55.
Figure 24: Phosphoramidite building block 56.
Figure 25: Structures of DNGs 57–65.
Figure 26: Structure of the phosphoramidite building block 66.
N-alkyl-N-(phosphonoethyl) substituted (meth)acrylamides – new adhesive monomers for self-etching self-priming one part dental adhesive
- Joachim E. Klee and
- Uwe Lehmann
Beilstein J. Org. Chem. 2009, 5, No. 72, doi:10.3762/bjoc.5.72
- , trimethylbromosilane, butylamine, 3,6-dioxaoctane-1,8-diamine, camphorquinone and 4-(N,N-dimethylamino)benzoic acid ethyl ester, diethyl (hydroxymethyl)phosphonate, 2,2′-azobisisobutyronitrile (AIBN) and 2,6-di-tert-butyl-4-methylphenol were purchased from Sigma-Aldrich and phenylbis(2,4,6-trimethylbenzoyl)phosphine
- mol % camphorquinone and 0.35 mol % 4-(N,N-dimethylamino)benzoic acid ethyl ester. The hydrolytic stability was studied by detection of acrylic or methacrylic acid in HPLC using solutions of 1.5 mmol of 3c, 3d and 3e and solutions of 0.6 mmol 3g in 5 mL of a 1:1 mixture of distilled water and ethanol
- , 0.0083 g 4-(N,N-dimethylamino)benzoic acid ethyl ester and 0.0179 g bis bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide were dissolved in a solvent mixture composed of 0.5000 g ethanol and 0.5000 g water. The following procedure was applied prior to adhesion measurement: At first teeth were abraded by
Graphical Abstract
Scheme 1: Synthesis of novel N-alkyl-N-(ethyl phosphonate) (meth)acrylamides 3. For 2a, 2b, 3a, 3b: R1 = H, x...
Figure 1: Hydrolysis of N-alkyl-N-(phosphonoethyl) substituted (meth)acrylamides 3 of Scheme 1 and of methacrylic aci...
Figure 2: Etch pattern of enamel etched with a) Conditioner 36, magnification 11 × 103, b) acidic monomer 3g (...
Figure 3: Shear bond strength (SBS) of phosphonic acids 3c, 3e, 3f and 3g in a formulation of an aqueous etha...
Novel banana-discotic hybrid architectures
- Hari Krishna Bisoyi,
- H. T. Srinivasa and
- Sandeep Kumar
Beilstein J. Org. Chem. 2009, 5, No. 52, doi:10.3762/bjoc.5.52
- (hexyloxy)triphenylene-2-yloxy]dodecyloxy}benzoic acid (4): A mixture of compound 3 (2.3 g) dissolved in 1,4-dioxane (20 ml) and 5% Pd-C catalyst (0.4 g) was stirred in an atmosphere of hydrogen until the required quantity of hydrogen was absorbed. The resulting mixture was filtered in hot and the solvent
Graphical Abstract
Scheme 1: Synthesis of banana bridged discotic dimer. Reagents and conditions; (i) Br(CH2)12Br, Cs2CO3, MEK, ...
Scheme 2: Synthesis of banana-discotic dimers.
Gold film- catalysed benzannulation by Microwave- Assisted, Continuous Flow Organic Synthesis (MACOS)
- Gjergji Shore,
- Michael Tsimerman and
- Michael G. Organ
Beilstein J. Org. Chem. 2009, 5, No. 35, doi:10.3762/bjoc.5.35
- -benzoic acid (1.71 mmol, 250 mg) in 6 mL of dry THF was added over 10 min. When the addition of acid was complete, 3 drops of DMF were added to the mixture and bubbling was observed. After stirring for 30 min. at 0 °C, the solution was stirred an additional 30 min. at rt, and then cooled back to 0 °C
- -carbonyl)naphthalen-2-yl]-benzoic acid (4e). Following the general MACOS benzannulation protocol, 2-(2-(thiophen-3-yl)-ethynyl)-benzaldehyde (1d) and 3-ethynylbenzoic acid were reacted and 700 μL of the crude reaction mixture were collected. Purification by flash chromatography (10% methanol in
Graphical Abstract
Figure 1: Mechanism of Au(III)-catalyzed benzannulation between aromatic carbonyls and alkynes.
Figure 2: X-ray analysis of the metal films used in this benzannulation study. Panels a–e are scanning-electr...
Silica- bound benzoyl chloride mediated the solid- phase synthesis of 4H-3,1-benzoxazin- 4-ones
- Kurosh Rad-Moghadam and
- Somayeh Rouhi
Beilstein J. Org. Chem. 2009, 5, No. 13, doi:10.3762/bjoc.5.13
- synthesis of SBBC through which first the surface of silica gel was converted to silica chloride by means of reaction with thionyl chloride [27][28]. The silica chloride was heated with 4-hydroxybenzoic acid to form the silica-bound benzoic acid (SBBA). The SBBA was washed with acetone to remove excess 4
Graphical Abstract
Scheme 1: Three-step synthesis of silica-bound benzoyl chloride.
Scheme 2: Plausible mechanisms for the synthesis of benzoxazinones 5a–f.
Trifluoromethyl ethers – synthesis and properties of an unusual substituent
- Frédéric R. Leroux,
- Baptiste Manteau,
- Jean-Pierre Vors and
- Sergiy Pazenok
Beilstein J. Org. Chem. 2008, 4, No. 13, doi:10.3762/bjoc.4.13
- lithiation next to the OCF3 substituent is favoured, probably due to steric reasons. In fact, 1-trifluoromethoxy-4-(trifluoromethyl)benzene (Scheme 15) affords 2-trifluoromethoxy-5-(trifluoromethyl)benzoic acid after lithiation and carboxylation [75]. When the OCF3 substituent is in competition with fluorine
Graphical Abstract
Figure 1: OCF3-bearing pesticides.
Scheme 1: Preparation of trifluoromethyl ethers via a chlorination/fluorination sequence.
Scheme 2: Preparation of trifluoromethyl ethers via an in situ chlorination/fluorination sequence.
Scheme 3: Preparation of trifluoromethyl ethers via chlorothionoformates.
Scheme 4: Preparation of trifluoromethyl ethers via fluoroformates.
Scheme 5: Oxidative desulfurization-fluorination toward trifluoromethyl ethers.
Scheme 6: Mechanism of the oxidative desulfurization-fluorination.
Scheme 7: Umemoto's O-(trifluoromethyl)dibenzofuranium salts 4 as CF3-transfer agents.
Scheme 8: Togni's approach using hypervalent iodine compounds as CF3-transfer agents.
Scheme 9: TAS OCF3 as a nucleophilic OCF3-transfer agent.
Figure 2: Mesomeric structures of the OCF3-group.
Figure 3: Structures of 6 and 7.
Figure 4: Conformational preference of the trifluoromethoxy group on aryl rings.
Scheme 10: Nitration of trifluoromethoxy benzene.
Scheme 11: Synthesis and Nitration of N-Acetyl-(trifluoromethoxy)anilines.
Scheme 12: Bromine/lithium exchange of bromo(trifluoromethoxy)benzenes.
Scheme 13: Metalation of (trifluoromethoxy)benzene.
Scheme 14: Metalation of (trifluoromethoxy)naphthalenes.
Scheme 15: Competition between -CF3- and -OCF3 in Metalation reactions.
Scheme 16: Competition between -F- and -OCF3 in Metalation reactions.
Scheme 17: Metalation of trifluoromethoxyanisoles.
Figure 5: Direction of π-polarization depending on the substituent as described by Schlosser et al. [57].
Scheme 18: Metalation of Bromo(trifluoromethoxy)benzenes.
Scheme 19: Aryne formation from bromo(trifluoromethoxy)phenyllithiums and subsequent Diels-Alder cycloaddition...
Scheme 20: Metalation of (trifluoromethoxy)anilines.
Electronic differentiation competes with transition state sensitivity in palladium- catalyzed allylic substitutions
- Dominik A. Lange and
- Bernd Goldfuss
Beilstein J. Org. Chem. 2007, 3, No. 36, doi:10.1186/1860-5397-3-36
- of substrate and catalyst structures. "Side arm guidance" of nucleophiles with multifunctional phosphinoferrocenes [14][15][16][17][18] or "chiral pockets" in C2-symmetric diphosphanes based on 2-(diphenyl-phosphino)benzoic acid amides [19][20][21][22] were applied especially successfully. Chiral P,N
Graphical Abstract
Scheme 1: Electronic and steric differentiations provide the basis for the high selectivity of P,N-ligands in...
Scheme 2: Activation (ΔEa) and reaction (ΔEr) energies (kcal mol-1), computed for the P,N-ligand model with t...
Figure 1: Transition structure for the energetically favored trans to phosphorus addition of ammonia at the P...
Figure 2: Transition structure for the energetically disfavored cis to phosphorus addition of ammonia at the ...
Figure 3: Transition structure for the energetically disfavored trans to phosphorus addition of ammonia at th...
Figure 4: Transition structure for the energetically favored cis to phosphorus addition of ammonia at the Pd-η...
Figure 5: Transition structure for the energetically favored trans to phosphorus addition of ammonia at the P...
Figure 6: Transition structure for the energetically disfavored cis to phosphorus addition of ammonia at the ...
Figure 7: Transition structure for the energetically disfavored cis to phosphorus addition of ammonia at the ...
Figure 8: Transition structure for the energetically favored trans to phosphorus addition of ammonia at the P...
Figure 9: For each phosphabenzene moiety, the site selectivities ΔEaTS increase with more electron withdrawin...
Figure 10: Higher site selectivities, i.e. larger ΔEaTS values, are found for earlier transition structures wi...
Figure 11: Higher site selectivities, i.e. larger ΔEaTS values, are found for transition structures with close...
EcoScale, a semi- quantitative tool to select an organic preparation based on economical and ecological parameters
- Koen Van Aken,
- Lucjan Strekowski and
- Luc Patiny
Beilstein J. Org. Chem. 2006, 2, No. 3, doi:10.1186/1860-5397-2-3
- benzoic acid [24] Synthesis of benzamide [25] Synthesis of benzamide using HMDS [26] The penalty points to calculate the EcoScale The penalty points for example 1 The penalty points for example 2 The penalty points for example 3 The penalty points for example 4
Graphical Abstract
Scheme 1: Reduction of nitrobenzene to aniline [23]
Scheme 2: Oxidation of benzyl chloride to benzoic acid [24]
Scheme 3: Synthesis of benzamide [25]
Scheme 4: Synthesis of benzamide using HMDS [26]
