Design and Synthesis of Novel 20-epi Analogues of Calcitriol with Restricted Side Chain Conformation

The design and efficient preparation of two 20-epi analogues of calcitriol with restricted side chain conformation is described. The formation of the tetrahydropyran ring was achieved via zinc chloride mediated etherification of alcohols. Docking experiments show that these novel analogues could be interesting synthetic targets.