A convenient synthesis of 5beta-cholestan-26-oic and 5beta-cholestan-26,27-dioic acids.

@article{Starchenkov2000ACS,
  title={A convenient synthesis of 5beta-cholestan-26-oic and 5beta-cholestan-26,27-dioic acids.},
  author={I Starchenkov and Pēteris Trapencieris and Valerjans Kauss and Gerhard Jas and Ivars Kalvinsh},
  journal={Steroids},
  year={2000},
  volume={65 3},
  pages={143-7}
}
A new method for the preparation of 5beta-cholestan-26-oic acids 7 and their analogs is described. The key steps in the synthesis are: iodination of bis- and tris-formyloxy-5beta-cholan-24-ols 3; nucleophilic substitution of iodides 4 with diethyl sodiomalonate; complete alkaline hydrolysis of esters 5; and subsequent decarboxylation of geminal diacids 6 in DMSO.