Preparation of 1',2 '-, 3 ',4 '-, and 4 ',5 '-epoxy derivatives of nucleosides and their use for the stereoselective synthesis of 1'- and 4 '-branched analogues are described.
A NEW APPROACH TO THE SYNTHESIS OF 4′-CARBON-SUBSTITUTED NUCLEOSIDES: DEVELOPMENT OF A HIGHLY ACTIVE ANTI-HIV AGENT 2′, 3′-DIDEHYDRO-3′-DEOXY-4′-ETHYNYLTHYMIDINE
作者:Kazuhiro Haraguchi、Shingo Takeda、Masanori Sumino、Hiromichi Tanaka、Ginger E. Dutschman、Yung-Chi Cheng、Takao Nitanda、Masanori Baba
DOI:10.1081/ncn-200059774
日期:2005.4.1
Oxidation of 3'-O-TBDMS-4',5'-unsaturated thymidine 3 with dimethyldioxirane (DMDO) allowed the isolation of the epoxide 4. Upon reacting with organosilicon reagents in the Presence of SnCl4, 4 underwent stereoselective ring opening to give 4'-alpha-allyl (6), 4'-alpha-(2-bromoallyl) (7), 4'-alpha(cyclopenten-3-yl) (8), and 4'-alpha-cyano (9) derivatives of thymidine. Reactions of the 3'-epimer 12 with organoaluminum reagents gave 4-alpha-methyl (13), 4'-alpha-vinyl (14), and 4'-alpha-ethynyl (15) analogues. Compounds 13-15 were transformed into corresponding 2',3'-didehydro-3'-deoxy derivatives. Evaluation of their ability to inhibit the replication of HIV in cell culture showed that 4'-ethynyl-d4T (19) is more potent and less toxic than the parent compound d4T.
Synthesis of a highly active new anti-HIV agent 2′,3′-Didehydro-3′-deoxy-4′-ethynylthymidine
Compounds having methyl, vinyl, and ethynyl groups at the 4'-position of stavudine (d4T: 2',3'-didehydro-3'-deoxythymidine) were synthesized. The compounds were assayed for their ability to inhibit the replication of HIV in cell culture. The 4'-ethynyl analogue (15) was found to be more potent and less toxic than the parent compound stavudine. (C) 2003 Elsevier Ltd. All rights reserved.