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Search for "Pummerer reaction" in Full Text gives 4 result(s) in Beilstein Journal of Organic Chemistry.
Synthetic strategies toward 1,3-oxathiolane nucleoside analogues
- Umesh P. Aher,
- Dhananjai Srivastava,
- Girij P. Singh and
- Jayashree B. S
Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182
Graphical Abstract
Figure 1: Representative modified 1,3-oxathiolane nucleoside analogues.
Figure 2: Mechanism of antiviral action of 1,3-oxathiolane nucleosides, 3TC (1) and FTC (2), as chain termina...
Figure 3: Synthetic strategies for the construction of the 1,3-oxathiolane sugar ring.
Scheme 1: Synthesis of 4 from benzoyloxyacetaldehyde (3a) and 2-mercapto-substituted dimethyl acetal 3na.
Scheme 2: Synthesis of 8 from protected glycolic aldehyde 3b and 2-mercaptoacetic acid (3o).
Scheme 3: Synthesis of 20 from ᴅ-mannose (3c).
Scheme 4: Synthesis of 20 from 1,6-thioanhydro-ᴅ-galactose (3d).
Scheme 5: Synthesis of 8 from 2-(tert-butyldiphenylsilyloxy)methyl-5-oxo-1,2-oxathiolane (3m).
Scheme 6: Synthesis of 20a from ʟ-gulose derivative 3f.
Scheme 7: Synthesis of 31 from (+)-thiolactic acid 3p and 2-benzoyloxyacetaldehyde (3a).
Scheme 8: Synthesis of 35a from 1,4-dithiane-2,5-diol (3q) and glyoxylic acid (3g) hydrate.
Scheme 9: Synthetic routes toward 41 through Pummerer reaction from methyl 2-mercaptoacetate (3j) and bromoac...
Scheme 10: Strategy for the synthesis of 2,5-substituted 1,3-oxathiolane 41a using 4-nitrobenzyl glyoxylate an...
Scheme 11: Synthesis of 44 by a resolution method using Mucor miehei lipase.
Scheme 12: Synthesis of 45 from benzoyloxyacetaldehyde (3a) and 2-mercaptoacetaldehyde bis(2-methoxyethyl) ace...
Scheme 13: Synthesis of 46 from 2-mercaptoacetaldehyde bis(2-methoxyethyl) acetal (3nc) and diethyl 3-phosphon...
Scheme 14: Synthesis of 48 from 1,3-dihydroxyacetone dimer 3l.
Scheme 15: Approach toward 52 from protected alkene 3rb and lactic acid derivative 51 developed by Snead et al....
Scheme 16: Recent approach toward 56a developed by Kashinath et al.
Scheme 17: Synthesis of 56a from ʟ-menthyl glyoxylate (3h) hydrate by DKR.
Scheme 18: Possible mechanism with catalytic TEA for rapid interconversion of isomers.
Scheme 19: Synthesis of 35a by a classical resolution method through norephedrine salt 58 formation.
Scheme 20: Synthesis of 63 via [1,2]-Brook rearrangement from silyl glyoxylate 61 and thiol 3nb.
Scheme 21: Combined use of STS and CAL-B as catalysts to synthesize an enantiopure oxathiolane precursor 65.
Scheme 22: Synthesis of 1 and 1a from glycolaldehyde dimer 64 and 1,4-dithiane-2,5-diol (3q) using STS and CAL...
Scheme 23: Synthesis of 68 by using Klebsiella oxytoca.
Scheme 24: Synthesis of 71 and 72 using Trichosporon taibachii lipase and kinetic resolution.
Scheme 25: Synthesis of 1,3-oxathiolan-5-ones 77 and 78 via dynamic covalent kinetic resolution.
Figure 4: Pathway for glycosidic bond formation.
Scheme 26: First synthesis of (±)-BCH-189 (1c) by Belleau et al.
Scheme 27: Enantioselective synthesis of 3TC (1).
Scheme 28: Synthesis of cis-diastereomer 3TC (1) from oxathiolane propionate 44.
Scheme 29: Synthesis of (±)-BCH-189 (1c) via SnCl4-mediated N-glycosylation of 8.
Scheme 30: Synthesis of (+)-BCH-189 (1a) via TMSOTf-mediated N-glycosylation of 20.
Scheme 31: Synthesis of 3TC (1) from oxathiolane precursor 20a.
Scheme 32: Synthesis of 83 via N-glycosylation of 20 with pyrimidine bases.
Scheme 33: Synthesis of 85 via N-glycosylation of 20 with purine bases.
Scheme 34: Synthesis of 86 and 87 via N-glycosylation using TMSOTf and pyrimidines.
Scheme 35: Synthesis of 90 and 91 via N-glycosylation using TMSOTf and purines.
Scheme 36: Synthesis of 3TC (1) via TMSI-mediated N-glycosylation.
Scheme 37: Stereoselective N-glycosylation for the synthesis of 1 by anchimeric assistance of a chiral auxilia...
Scheme 38: Whitehead and co-workers’ approach for the synthesis of 1 via direct N-glycosylation without an act...
Scheme 39: ZrCl4-mediated stereoselective N-glycosylation.
Scheme 40: Plausible reaction mechanism for stereoselective N-glycosylation using ZrCl4.
Scheme 41: Synthesis of enantiomerically pure oxathiolane nucleosides 1 and 2.
Scheme 42: Synthesis of tetrazole analogues of 1,3-oxathiolane nucleosides 97.
Scheme 43: Synthetic approach toward 99 from 1,3-oxathiolane 45 by Camplo et al.
Scheme 44: Synthesis of 100 from oxathiolane phosphonate analogue 46.
Scheme 45: Synthetic approach toward 102 and the corresponding cyclic thianucleoside monophosphate 102a by Cha...
Scheme 46: Synthesis of emtricitabine (2) from 1,4-dithiane-2,5-diol (3q) and glyoxylic acid (3g).
Scheme 47: Synthesis of 1 and 2, respectively, from 56a–d using iodine-mediated N-glycosylation.
Scheme 48: Plausible mechanism for silane- and I2-mediated N-glycosylation.
Scheme 49: Pyridinium triflate-mediated N-glycosylation of 35a.
Scheme 50: Possible pathway for stereoselective N-glycosylation via in situ chelation with a metal ligand.
Scheme 51: Synthesis of novel 1,3-oxathiolane nucleoside 108 from oxathiolane precursor 8 and 3-benzyloxy-2-me...
Scheme 52: Synthesis of 110 using T-705 as a nucleobase and 1,3-oxathiolane derivative 8 via N-glycosylation.
Scheme 53: Synthesis of 1 using an asymmetric leaving group and N-glycosylation with bromine and mesitylene.
Scheme 54: Cytidine deaminase for enzymatic separation of 1c.
Scheme 55: Enzymatic resolution of the monophosphate derivative 116 for the synthesis of (−)-BCH-189 (1) and (...
Scheme 56: Enantioselective resolution by PLE-mediated hydrolysis to obtain FTC (2).
Scheme 57: (+)-Menthyl chloroformate as a resolving agent to separate a racemic mixture 120.
Scheme 58: Separation of racemic mixture 1c by cocrystal 123 formation with (S)-(−)-BINOL.
Unprecedented nucleophile-promoted 1,7-S or Se shift reactions under Pummerer reaction conditions of 4-alkenyl-3-sulfinylmethylpyrroles
- Takashi Go,
- Akane Morimatsu,
- Hiroaki Wasada,
- Genzoh Tanabe,
- Osamu Muraoka,
- Yoshiharu Sawada and
- Mitsuhiro Yoshimatsu
Beilstein J. Org. Chem. 2018, 14, 2722–2729, doi:10.3762/bjoc.14.250
- -1193, Japan School of Pharmacy, Kindai University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan Life Science Research Center, Gifu University, Yanagido 1-1, Gifu 501-1193, Japan 10.3762/bjoc.14.250 Abstract A unique 1,7-S- and Se-shift reaction under Pummerer reaction conditions of 4-alkenyl-3
- -sulfinyl- and seleninylpyrroles was described. The usual Pummerer reaction of 4-(alkenylaminomethyl)-3-phenylsulfinylpyrroles and a successive reaction with tetrabutylammonium hydroxide (TBAH) yielded either pyrrolo[3,2-c]azepines or N-pyrrol-3-ylmethyl-N-(4-hydroxy-3-sulfanylpropyl)-p-toluenesulfonamides
- (diols). Seleno-Pummerer reactions of 3-selanylmethylpyrroles also proceeded via in situ generation of selenoxides, followed by a treatment with TBAH. Keywords: hydroamination; Pummerer reaction; pyrrole; pyrroloazepine; 1,7-sulfur shift; Introduction Pyrrolo- and indoloazepine skeletons are chemical
Graphical Abstract
Scheme 1: Our synthetic plan for pyrrolo[3,2-c]azepines.
Scheme 2: Preparation of precursors for the Pummerer reactions.
Scheme 3: Substrate scope of 1,7-S and 1,7-Se shift reactions.
Scheme 4: Proposed mechanism.
Scheme 5: Crossover experiment.
Scheme 6: Lewis acid-catalysed cyclization of diols.
Scheme 7: Sequential process of sulfanyl-1,6-diyne 1 to 4H-pyrrolo[3,4-g]oxazine 25g.
Glycosylation reactions mediated by hypervalent iodine: application to the synthesis of nucleosides and carbohydrates
- Yuichi Yoshimura,
- Hideaki Wakamatsu,
- Yoshihiro Natori,
- Yukako Saito and
- Noriaki Minakawa
Beilstein J. Org. Chem. 2018, 14, 1595–1618, doi:10.3762/bjoc.14.137
- sila-Pummerer reaction by Kita, it was plausible that the reaction proceeded via the formation of sulfenium ion 14 which was formed by β-elimination of silylated sulfoxide 13. The 4’-thioDMDC derivative 15 was deprotected and the resulting anomeric mixture was separated to furnish 4’-thioDMDC (3) and
- in the case of 2’-deoxy-4’-thionucleosides [25][26]. When synthesizing 4’-thionucleosides by the way of a sulfide derivative 31, the known chemistry should lead us to use a classical Pummerer reaction to produce 1-acetoxy derivative 33 after converting 31 to the corresponding sulfoxide 32. Even
- though this scheme should be promising enough, we intended to introduce an additional synthetic idea based on the fact that both of the reaction intermediate of the Vorbrüggen reaction [15][16] of 33 and the sila-Pummerer reaction developed by Kita [29][30] involving sulfoxide 32 would be the same
Graphical Abstract
Figure 1: Design of potential antineoplastic nucleosides.
Scheme 1: Synthesis of 4’-thioDMDC.
Scheme 2: Synthesis of 4’-thioribonucleosides by Minakawa and Matsuda.
Scheme 3: Synthesis of 4’-thioribonucleosides by Yoshimura.
Figure 2: Concept of the Pummerer-type glycosylation and hypervalent iodine-mediated glycosylation.
Scheme 4: Oxidative glycosylation of 4-thioribose mediated by hypervalent iodine.
Figure 3: Speculated mechanism of oxidative glycosylation mediated by hypervalent iodine.
Scheme 5: Synthesis of purine 4’-thioribonucleosides using hypervalent iodine-mediated glycosylation.
Scheme 6: Unexpected glycosylation of a thietanose derivative.
Scheme 7: Speculated mechanism of the ring expansion of a thietanose derivative.
Scheme 8: Synthesis of thietanonucleosides using the Pummerer-type glycosylation.
Scheme 9: First synthesis of 4’-selenonucleosides.
Scheme 10: The Pummerer-type glycosylation of 4-selenoxide 74.
Scheme 11: Synthesis of purine 4’-selenonucleosides using hypervalent iodine-mediated glycosylation.
Figure 4: Concept of the oxidative coupling reaction applicable to the synthesis of carbocyclic nucleosides.
Scheme 12: Oxidative coupling reaction mediated by hypervalent iodine.
Scheme 13: Synthesis of cyclohexenyl nucleosides using an oxidative coupling reaction.
Figure 5: Concept of the oxidative coupling reaction of glycal derivatives.
Scheme 14: Oxidative coupling reaction of silylated uracil and DHP using hypervalent iodine.
Scheme 15: Proposed mechanism of the oxidative coupling reaction mediated by hypervalent iodine.
Figure 6: Synthesis of 2’,3’-unsaturated nucleosides using hypervalent iodine and a co-catalyst.
Scheme 16: Synthesis of dihydropyranonucleoside.
Scheme 17: Synthesis of acetoxyacetals using hypervalent iodine and addition of silylated base.
Scheme 18: One-pot fragmentation-nucleophilic additions mediated by hypervalent iodine.
Figure 7: The reaction of thioglycoside with hypervalent iodine in the presence of Lewis acids.
Scheme 19: Synthesis of disaccharides employing thioglycosides under an oxidative coupling reaction mediated b...
Scheme 20: Synthesis of disaccharides using disarmed thioglycosides by hypervalent iodine-mediated glycosylati...
Scheme 21: Glycosylation using aryl(trifluoroethyl)iodium triflimide.
Figure 8: Expected mechanism of hypervalent iodine-mediated glycosylation with glycals.
Scheme 22: Synthesis of oligosaccharides by hypervalent iodine-mediated glycosylation with glycals.
Scheme 23: Synthesis of 2-deoxy amino acid glycosides.
Figure 9: Rationale for the intramolecular migration of the amino acid unit.
Synthesis of methylenebisamides using CC- or DCMT- activated DMSO
- Qiang Wang,
- Lili Sun,
- Yu Jiang and
- Chunbao Li
Beilstein J. Org. Chem. 2008, 4, No. 51, doi:10.3762/bjoc.4.51
- include DCC [1][2], acetic anhydride [3], trifluoroacetic anhydride [4], acetyl chloride [5], phosphorus pentoxide [6], polyphosphoric acid [7], sulfuric acid and sulfur trioxide [6] etc. A few reactions such as the Pummerer reaction [8] and Swern oxidation [9] can be performed via the reactive sulfonium
Graphical Abstract
Scheme 1: Synthesis of N,N′-methylenedibenzamide using CC-activated DMSO.
Scheme 2: Synthesis of N,N′-methylenebisamide using CC-activated DMSO.
Scheme 3: Synthesis of N,N′-methylenedibenzamide using DCMT-activated DMSO.
Scheme 4: Synthesis of N,N′-methylenebisamide using DCMT-activated DMSO.
Scheme 5: Plausible reaction mechanism of amide with CC- or DCMT-activated DMSO.
