Synthesis of 3,4-, 4,5- and 5,6-unsaturated 19-substituted cholestane derivatives and related epoxides
1980 ◽
Vol 45
(11)
◽
pp. 3008-3022
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Starting from the 5,6-unsaturated compound X, 19-hydroxy-, 19-methoxy and 19-acetoxy derivatives with the double bond in positions 5,6- (XIV-XVI), 4,5- (XXI-XXIII) and 3,4- (XXX, XXXIII, XXXIV) were prepared by stepwise transposition of the 5,6-double bond. The route to 4,5-unsaturated steroids involves hypobromous acid addition (XVI → XVIII) followed by reductive removal of bromine and dehydration (XIX → XXI), Transposition of the 4,5-double bond to the 3,4-position is based on the conversion of the 4,5-olefin into 4β-alcohol (XXIII → XXVII) and pyrolysis of its benzoate (XXVIII → XXX).
1983 ◽
Vol 48
(12)
◽
pp. 3660-3673
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1983 ◽
Vol 48
(10)
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pp. 2994-3019
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Keyword(s):
1980 ◽
Vol 45
(11)
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pp. 3023-3029
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1982 ◽
Vol 47
(11)
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pp. 3062-3076
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1987 ◽
pp. 1969-1974
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1981 ◽
Vol 22
(28)
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pp. 2699-2702
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Keyword(s):
Keyword(s):
1980 ◽
Vol 45
(3)
◽
pp. 921-926
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Keyword(s):
1983 ◽
Vol 48
(12)
◽
pp. 3643-3659
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