ChemInform Abstract: Synthesis of Novel Nucleosides with a Fused Cyclopropane Ring Substituted by a Hydroxymethyl Group.

Abstract

Abstract The two diastereomers of a 3-oxabicyclo[3.1.0]hexan-2-ol 21a – b with the cyclopropane ring substituted by a hydroxymethyl group were synthesized from both products 17a and 18a obtained from the bromohydroxylation of epoxide 16a derived from 3-oxabicyclo[3.2.0]hept-6-en-2-one 15 . This preparation involved two stereospecific C 4 –C 3 ring contractions leading to cis , cis -trisubstituted cyclopropane compounds 18a and 12 . The hydroxylactols 21a – b thus obtained were diacetylated and the single product 22 was subjected to substitution at the anomeric position by protected or free bases, providing, in each case, only one of the possible products. Deprotection with ammonia yielded new bicyclic nucleosides 11a – d .