On The Protection of 3α-Hydroxy Group of A/BcisSteroids
摘要:
The difficulties encountered in the protection of 3-alpha-hydroxy group of lithocholic acid 1 with three different types of protective groups are described. Only benzyl ether derivative was found to be suitable for synthetic transformations. The methodology for the synthesis of benzyl ethers of A/B cis steroids is reported for the first time.
A Mild One-Pot Method for Conversion of Various Steroidal Secondary Alcohols into the Corresponding Olefins
作者:Henri Kagan、Raju Kumar、Shrutisagar Haveli
DOI:10.1055/s-0030-1260803
日期:2011.7
to some hydroxy steroids in the presence of excess base directly leads to steroidal olefins. This methodology is useful for the one-pot synthesis of Δ 2 - or Δ 3 -steroids under mild conditions from the corresponding alcohols.
Rearrangement spinal en serie a/b : conversion du lithocholate de methyle en derives du d-homoandrostane
作者:C. Aubert、J.P. Bégué、D. Bonnet-Delpon
DOI:10.1016/s0040-4020(01)96368-9
日期:1985.1
A new backbonerearrangement is observed in A/B cis methyl lithocholate derivatives. It is initiated from the C-3 carbon either by dehalogenation of the chloroesters 1 by AgSbFg6 or by the action of the triflic anhydride on the si1y1ated ether 2. This rearrangement leads to methyl diacholenate 3 and new lactones in D-homoandrostane series 5 and 6. The differences of behaviour between A/B cis and A/B
A new example under novel conditions of backbone rearrangement of steroids; conversion of methyl lithocholates into<scp>D</scp>-homoandrostane derivatives
作者:Jean-Pierre Bégué、Danièle Bonnet-Delpon
DOI:10.1039/c39840000402
日期:——
The backbonerearrangement of the silyl ether of methyl lithocholate (1) leads to D-homoandrostane epimeric lactones (2) in 40% yield.