Synthesis and biological evaluation of 1α-hydroxy-25(R and S)-25,26-Epoxy-23-yne vitamin D3 and of 1α,25(R and S),26-Trihydroxy-23-yne vitamin D3
摘要:
The synthesis of both 1 alpha-hydroxy-25(R and S)-25,26-epoxy-23-yne vitamin D-3 and of both 1 alpha,2S(R and S),26-trihydroxy-23-yne vitamin D-3 is described. Biological evaluation includes the study of calcemic effect, receptor binding and cell differentiation. (C) 1997 Published by Elsevier Science Ltd.
Synthesis and biological evaluation of 1α-hydroxy-25(R and S)-25,26-Epoxy-23-yne vitamin D3 and of 1α,25(R and S),26-Trihydroxy-23-yne vitamin D3
摘要:
The synthesis of both 1 alpha-hydroxy-25(R and S)-25,26-epoxy-23-yne vitamin D-3 and of both 1 alpha,2S(R and S),26-trihydroxy-23-yne vitamin D-3 is described. Biological evaluation includes the study of calcemic effect, receptor binding and cell differentiation. (C) 1997 Published by Elsevier Science Ltd.
14 to the aldehyde 21, followed by oxidation, dissolving metal reduction and stereoselective reduction of the C8 carbonyl group resulted in 29, which has the correct stereochemistry at C8 and C9. Further conversion of 29 into 37, and attempted intramolecular cyclization resulted in fragmentation to the furan 39 and 38. Asymmetric epoxidation of the allylicalcohols 42 and 48 resulted in neighboring
Facile chemoenzymic preparation of enantiomerically pure 2-methylglycerol derivatives as versatile trifunctional C4-synthons
作者:Beat Wirz、Richard Barner、Joseph Huebscher
DOI:10.1021/jo00067a034
日期:1993.7
Both enantiomers of a series of synthetically valuable 2-methylglycerol derivatives have been prepared with >99% ee using a chemoenzymatic reaction sequence. The introduction of chirality was achieved by enantioselective esterification of 1,2-O-protected 2-methylglycerol 3 or enantioselective hydrolysis of its butyryl ester 4. The enzymatic reaction proceeded with unusually high selectivity and velocity for a primary alcohol (ester) substrate.