Novel steroidal metal complexes with potential pharmaceutical applications

A study to develop novel lipophilic metal ion complexes based on dihydrocholesterol was undertaken. Steroid ligands functionalised at the 2- and 3- positions were synthesized as possible bidentate ligands for complexation of metal ions. Condensation of 5α-cholestan-3-one with ethyl formate in the presence of base gave 2-hydroxymethylene-5α-cholestan-3-one, and 2- acetyl-5α-cholestan-3-one was obtained by the reaction between 3- trimethylsilyloxy-5α-cholest-2-ene and acetyl chloride. Attempts to synthesize 2,3-dioximino-5α-cholestane from 5α-cholestan-3-one and 2α-hydroxy-5α-cholestan-3-one were unsuccessful. Likewise 2- methylene-5α-cholestan-3-one, which was expected to lead to other bidentate ligands, could not be prepared satisfactorily from 5α-cholestan- 3-one or 3-trimethylsilyloxy-5α-cholest-2-ene. [Continues.]