Androstanes and Oestranes

Syntheses of 16,17-disubstituted oestra-l,3 5(10),14-tetraene 3-methyl ethers involved reaction of the corresponding 16,17-epoxides with various nucleo-philes and similar reactions of the 17,20-epoxides (300) gave a range of androstanes (301). A series of 16j8-alkylated androstanes and oestranes has... 

Miscellaneous Rearrangements.—An improved non-photochemical route to 13-epi-androstanes and -oestranes involved conversion of the appropriate 17-oximino-compounds with boiling acetic anhydride-pyridine into the enamide (176) and the enimide (177) which were readily hydrolysed to the 17-oxo-... 

Several groups are included in this class of steroids including corticosteroids, pregnanes, androstanes and oestranes. Extensive reviews on the chromatography of these compounds have been previously published (Heftman, 1983 Heftman and Lin, 1982 Purdy et al, 1982 O Hare and Nice, 1982 Schmidt, 1982). It is not the purpose of this section to provide a comprehensive review of the Uterature but to provide the potential chromatographer with a number of alternative strategies for the separation and detection of the various steroid hormones. For ease of reference the individual classes of steroid hormones have been separated into individual sub-sections. 

A number of other synthetic approaches to the steroid skeleton are discussed in the following sections, which are devoted more specifically to the synthesis of oestrane, androstane, and pregnane derivatives, as well as to seco-compounds and steroidal alkaloids. 

The neutral derivatives of the oestrane, androstane and pregnane basic skeleton are the principal members of this large and important... 

The structures of the 9-methyl-5a,9j8,10a-oestran-3-one (1) and its 2a- and 2/8-bromo-derivatives have been studied by X-ray crystallography. Ring A in the 2/8-bromo-compound is forced into a twist-boat conformation by steric compression (2/8-Br/9/3-Me), but the other two compounds are only slightly deformed from the chair conformation. These findings are compatible with the properties (c.d. and n.m.r.) of the same compounds in solution. 3a-Acetoxy-4a,8a,14/8-trimethyl-18-nor-5a,9/3,13a-androstan-17-one (2), another steroid of unusual configuration, derived from fusidic acid, has a twisted boat conformation of ring B. ... 

Hydroxy-17a-ethynyl-oestranes and -androstanes readily add nitrile oxides to give the novel 17a-isoxazoles (533 R = Ph, Me or C02Et) with reduced oestrogenic activity. 

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