Synthesis of a Series of Purine 2′,3′-Dideoxy-L-Nucleoside Analogues as Potential Antiviral Agents
作者:Tai-Shun Lin、Mei-Zhen Luo、Ju-Liang Zhu、Mao-Chin Liu、Yong-Lian Zhu、Ginger E. Dutschman、Yung-Chi Cheng
DOI:10.1080/15257779508009755
日期:1995.10
Various 2',3'-dideoxy-L-nucleoside analogues, 6-amino-9-(2,3-dideoxy-beta-L-ribofuranosy))purine (19), 2-chloro-6-amino-9-(2,3-dideoxy-beta-L-ribofuranosyl)-purine (20), 2-chloro-6-amino-9-(2,3-dideoxy-4-thio-beta-L-ribofuranosyl)purine (21), 2,5- diamino 9-(2,3-dideoxy-beta-L-ribofuranosyl)purine (26), 2,6-diamino-9-(2,3-dideoxy-4-thio-beta-L-ribofuranosyl)-purine (27), 2-amino-6-chloro-9-(2,3-dideoxy-beta-L-ribofuranosyl)purine (28), (6-chloro-9-(2,3-dideoxy-4-thio-beta-L-ribofuranosyl)purine (29), and 6-amino-9-(2,3-dideoxy-4-thio-beta-L-ribofuranosyl)purine (30) have been synthesized by coupling of the sodium salt of 2-amino-6-chloropurine (1), 6-chloropurine (2), and 2,6-dichloropurine urine (3) with 1-O-acetyl-5-O-(tert-butyldimethylsilyl)-2,3-dideoxy-L-ribofuranose (4) or 1-O-acetyl-5-O-(tert-butyldiphenylsilyl)-2,3-dideoxy-4-thio-L-ribofuranose (5) in anhydrous MeCN in the presence of either EtAlCl(2) or Et(2)AlCl followed by separation of the alp-anomers and deprotection of the blocking groups. However, the synthesis of 9-(2,3-dideoxy-beta-L-ribofuranosyl)guanine (57, beta-L-ddG) was not straightforward. Coupling of the silylated N-2-palmitoylguanine (48) with sugar 4 in anhydrous MeCN, using trimethylsilyl trifluoromethanesulfonate as a catalyst yielded N-9-beta- and N-9-alpha-; N-7-beta- and N-7-alpha-isomers, compounds 49-52, which were separated by silica gel column chromatography with two appropriate eluting solvent systems. Removal of the protecting groups gave compound 57 (beta-L-ddC) and the other 3 related isomers (58-60). The 2',3'-dideoxy-L-nucleoside analogues were tested in vitro against HIV-1, HBV, L1210, P388, S-180, and CCRF-CEM. 6-Amino-9-(2,3-dideoxy-beta-L-ribofuranosyl)purine (19, beta-L-ddA) was found to have antiviral activity against HBV with an ED(50) value of 6 mu M.