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5a-ChoIestan

Under these conditions 5a-methyl-5a-choIestane-3j5,6/ -diol (5) is obtained from the corresponding 5/ ,6/ -epoxide (4).126 The 6)5-methyl-3)5,5a-diols... [Pg.49]

Hydroxy-B-homo-5a-choIestan-7-one, 375 30-Hydroxy-B-homo-5a-cholestan-7-one acetate, 376, 377, 378... [Pg.238]

Reduction of Ketones.—Reduction of a series of C-5-substituted 5a-choIestan-3-ones (123) with LiAlH(ButO)3 gave C-3 alcohols with axial equatorial ratios which showed no obvious correlation with any of the usual steric or electronic parameters t3° J. C. Hilscher, Chem. Ber., 1975,108, 727. [Pg.242]

Trimethylaluminium in a hydrocarbon solvent exhaustively methylates ketones 144 5a-choIestan-3-one gave 3,3-dimethyl-5a-cholestane in good yield (other related transformations, COH->CMe145 and C02H- CMe3,146 have not yet been applied to steroids). [Pg.246]

Some steroidal methoxymethyl ethers exhibit intense molecular ions, unlike many other acetals. Mass spectral studies are also reported for C(19)-substituted 5a-choiestanes, and B-fluoroandrost-S-enes " and -5(10)-enes. ... [Pg.242]

Recently, Jones and Grayshan have reported the reaction of lithiodithiane derivatives with steroidal epoxides to effect preparation of modified steroids. Treatment of 2 ,3a-oxiranyl-5a-choIestane (46) with 2-lithio-l,3-dithiane, followed by desulphurization, yielded the 2]8-methyl-3a-cholestanol 47 (equation 48). Conversely, reaction with the epimeric epoxide 48 furnished 3a-methyl-5a-cholestan-2j8-ol (49) (equation 49) . [Pg.299]

Substrates used 2-benzylidenecyclohexanone, 2-benzylidene-5a-choiestan-3-one, and 17 j -benzoyIoxy-2-benzylidene-Sa-androstan-3-one. [Pg.14]

S 25ft)-22,26-Acetylepimino-5a-choIestane-3, 16j8-diol (A -acetyltetrahydrosolasodine... [Pg.150]

Figure 17 Comparison of conventional CD (solid line) with the CD converted from FDCD (dashed iine) for 5a-choiestane-3p,6a-dioi bis(2-arrthroate) in MeCN. Figure 17 Comparison of conventional CD (solid line) with the CD converted from FDCD (dashed iine) for 5a-choiestane-3p,6a-dioi bis(2-arrthroate) in MeCN.
See other pages where 5a-ChoIestan is mentioned: [Pg.436]    [Pg.359]    [Pg.361]    [Pg.259]    [Pg.416]    [Pg.29]    [Pg.427]    [Pg.358]    [Pg.226]    [Pg.23]    [Pg.30]    [Pg.243]    [Pg.388]    [Pg.20]    [Pg.846]    [Pg.170]    [Pg.69]    [Pg.275]    [Pg.275]    [Pg.275]    [Pg.372]    [Pg.100]   
See also in sourсe #XX -- [ Pg.3 , Pg.3 , Pg.344 ]



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