An Alternative Synthetic Method for 4′-C-Ethynylstavudine by Means of Nucleophilic Substitution of 4′-Benzoyloxythymine Nucleoside
作者:Kazuhiro Haraguchi、Masanori Sumino、Hiromichi Tanaka
DOI:10.1080/15257770701503969
日期:2007.11.26
For the synthesis of 2,3'-didehydro-3'-deoxy-4'-C-ethynylthymidine (8: 4'-Ed4T), a recently reported promising anti-HIV agent, a new approach was developed. Since treatment of 1-(2,5-dideoxy-beta-L-glycero-pent-4-enofuranosyl)thymine with Pb(OBz)(4) allowed the introduction of a 4'-benzoyloxy leaving group, nucleophilic substitution at the 4'-position became feasible, for the first time. Thus, reaction between the 4'-benzoyloxy derivative (H) and Me3SiC CAl(Et)Cl as a nucleophile led to the isolation of the desired 4'-"down"-ethynyl derivative (15) stereoselectively in 62 % yield.