113301-14-7Relevant academic research and scientific papers
18-Substituted Steroids. Part 13. Improved Preparation of the Metabolites of Aldosterone Reduced in Ring A
Kirk, David N.,Rajagopalan, Maruthiandan S.
, p. 1343 - 1346 (2007/10/02)
Protection of the side-chain of aldosterone as the 21-t-butyldimethylsilyl (TBDMS) ether was also found to mask the 20-oxo function, by effectively locking the tautomeric structure of aldosterone into its 11,18:18,20-diepoxy form.Catalytic hydrogenation of aldosterone 21-TBDMS ether gave the 5α- or the 5β-dihydro derivative depending on the choice of solvent.Subsequent reduction of the carbonyl group at C-3, with either 'K-selectride' to form the 3-axial alcohol or lithium tri-t-butoxyaluminium hydride to form the 3-equatorial alcohol, was found to proceed without attack on the side-chain, to give convenient routes to the four isomeric tetrahydroaldosterones.
18-Substituted Steroids. Part 7. Synthesis and Structure of 11β,18-Epoxy-3α,18,21-trihydroxy-5β-pregnan-20-one (3α,5β-Tetrahydroaldosterone)
Kirk, David N.,Miller, Barry W.
, p. 2818 - 2829 (2007/10/02)
3α,5β-Tetrahydroaldosterone (1) has been prepared from 21-deoxy-3α,5β-tetrahydroaldosterone 18-methyl ether 3-(tetrahydropyran-2-yl) ether (6).Kinetically controlled enolisation with lithium di-isopropylamide followed by treatment with chlorotrimethylsilane generated specifically the Δ20(21)-trimethylsilyl enol ether (17), which reacted with 3-chloroperbenzoic acid to give the 18-methyl ether-21-alcohol (18), which was converted into its 21-acetate (27).Acid solvolysis of the protecting groups at C-3 and -18 with anhydrous acetic acid, followed by mild alkaline hydrolysis with sodium hydrogencarbonate afforded 3α,5β-tetrahydroaldosterone (1) in 26percent overall yield.
