Synthesis of steroidal dimers: Selective amine catalysed steroidal dimerization

Abstract

Some new dimeric steroids namely cholest-5-en-3-spiro-[6′ α,5′-oxa]-5′ α-cholest-3′-one (2), cholest-5-en-7-spiro-[4′ α,5′-oxa]-5′ α-cholest-7′-one (4a) and 3β-substitutedcholest-5-en-7-spiro-[4′ α,5′-oxa]-3′ β-substituted-5′ α-cholestan-7′-ones (4b, c) are synthesized starting from cholest-5-en-3-one (1), cholest-5-en-7-one (3a) and 3β-substituted-cholest-5-en-7-ones (3b, c) respectively by using DMAP and xylene. All the synthesized compounds were characterized by using IR, MS and 1H, 13C NMR spectral and elemental analysis. Steroidal dimers (2, 4a–c) have been synthesized by the reaction of steroidal ketones (1, 3a–c) with DMAP in xylene. The synthesized compounds were characterized by using IR, MS and 1H, 13C NMR spectral techniques and elemental analysis.