A novel approach to the stereocontrolled synthesis of steroid side chains including the CD-ring system: the first total synthesis of (+)-8.alpha.-(phenylsulfonyl)-des-AB-cholestane and its efficient conversion into Grundmann's ketone and vitamin D3
Vitamin D 3 synthetic studies. Intramolecular Diels-Alder approaches to the CD-ring fragment
作者:Martin C. Clasby、Donald Craig、Albert A. Jaxa-Chamiec、Justine Y.Q. Lai、Andrew Marsh、Alexandra M.Z. Slawin、Andrew J.P. White、David J. Williams
DOI:10.1016/0040-4020(96)00147-0
日期:1996.3
The enantiospecific synthesis of the vitamin D3 CD ring fragment 3 is reported. Key steps are the diastereoselective allylation of a norephedrine/dihydrocitronellic acid-derived oxazolidinone, and the intramolecularDiels-Alder reaction of a sulfonyl-substituted dienyne. The analogous cycloaddition reaction of a trienylsulfone substrate is shown to give products having the incorrect stereochemistry
Vitamin D<sub>3</sub>Synthetic Studies. A Three-Step Procedure for the Preparation of (+)-(1<i>R</i>,5<i>R</i>,6<i>R</i>,9<i>R</i>,2′<i>R</i>)-1-Methyl-9-(6-methylhept-2-yl)-5-(phenylsulfonyl)bicyclo[4.3.0]nonane from Windaus-Grundmann Ketone
作者:Martin C. Clasby、Donald Craig
DOI:10.1080/00397919408011498
日期:1994.2
A procedure is described for the preparation of vitamin D3 key fragment (+)-(1R,5R,6R,9R,2'R)-1-methyl-9-(6-methylhept-2-yl)-5-(phenylsulfonyl)bicyclo[4.3.0]nonane 3 in three steps and 55% overall yield from Windaus-Grundmann ketone 5.
Clasby, Martin C.; Craig, Donald; Marsh, Andrew, Angewandte Chemie, 1993, vol. 105, # 10, p. 1495 - 1497