Chemoenzymatic synthesis of glycosylated enantiomerically pure 4-pentene 1,2- and 1,3-diol derivatives
摘要:
1-Dimethylthexylsiloxy-2-chloroacetoxy-4 2 and 1-dimethylthexylsiloxy-3-chloroacetoxy-4-pentene 3 were saponified with Pseudomonas lipase to give (R)-1-dimethylthexylsiloxy-4-pentene-2-ol (ee=99%) and (S)-2 (ee=99%) and (S)-1-dimethylthexylsiloxy-4-pentene-3-ol (ee=99%) and (R)-3 (ee=98%), respectively. All enantiomers were chemically transformed into the corresponding enatiomerically pure 2-benzoyloxy-4-pentene-1-ols 8 and 3-benzoyloxy-4-pentene-1-ols 14, respectively. Mannosylation of (R)-8 and (S)-14 with 2,3,4,6-tetra-O-benzoyl-a-D-mannopyranosyl trichloroacetimidate afforded the corresponding mannopyranosides. (C) 1998 Elsevier Science Ltd. All rights reserved.
Chemoenzymatic synthesis of glycosylated enantiomerically pure 4-pentene 1,2- and 1,3-diol derivatives
摘要:
1-Dimethylthexylsiloxy-2-chloroacetoxy-4 2 and 1-dimethylthexylsiloxy-3-chloroacetoxy-4-pentene 3 were saponified with Pseudomonas lipase to give (R)-1-dimethylthexylsiloxy-4-pentene-2-ol (ee=99%) and (S)-2 (ee=99%) and (S)-1-dimethylthexylsiloxy-4-pentene-3-ol (ee=99%) and (R)-3 (ee=98%), respectively. All enantiomers were chemically transformed into the corresponding enatiomerically pure 2-benzoyloxy-4-pentene-1-ols 8 and 3-benzoyloxy-4-pentene-1-ols 14, respectively. Mannosylation of (R)-8 and (S)-14 with 2,3,4,6-tetra-O-benzoyl-a-D-mannopyranosyl trichloroacetimidate afforded the corresponding mannopyranosides. (C) 1998 Elsevier Science Ltd. All rights reserved.
The Use of COP-OAc in the Catalyst-Controlled Syntheses of 1,3-Polyols
作者:Stefan Kirsch、Philipp Klahn、Helge Menz
DOI:10.1055/s-0031-1289574
日期:2011.11
Elongation via RCM (Cycle A) 2.2 TotalSynthesis of Rugulactone 2.3 Chain Elongation via Ando Olefination (Cycle B) and Total Syntheses of Polyrhacitides A and B 2.4 Useful Variants 3 Conclusions polyols - palladium - catalysis - natural products - esters