Synthesis of 3-methylisoguanosine, a positional isomer of pharmacologically active nucleosides from marine animals
作者:Taisuke Itaya、Tsunehiro Harada
DOI:10.1016/s0040-4039(00)87300-1
日期:1982.1
ITAYA, TAISUKE;HARADA, TSUNEHIRO, CHEM. AND PHARM. BULL., 38,(1990) N1, C. 2971-2976
作者:ITAYA, TAISUKE、HARADA, TSUNEHIRO
DOI:——
日期:——
OTSUKA, JODZO;ATEHMA, SAKAEHKO
作者:OTSUKA, JODZO、ATEHMA, SAKAEHKO
DOI:——
日期:——
JPS5651481A
申请人:——
公开号:JPS5651481A
公开(公告)日:1981-05-09
3-Methylisoguanosine: Synthesis and acidic hydrolysis of the glycosyl bond.
作者:Taisuke ITAYA、Tsunehiro HARADA
DOI:10.1248/cpb.38.2971
日期:——
Dehydration of 5-(cyanomethylamino)-1-methyl-1H-imidazole-4-carboxamide (14a) with a combination of phosphorus oxychloride and triethylamine afforded the nitrile 17a. This compound underwent selective hydration at the cyanamide moiety to furnish the urea 18a followed by cyclization to 3, 9-dimethylisaguaninae (19a) under alkaline conditions. Similar dehydration of the nucleoside analog 14b followed by treatment with 0.1 N aqueous sodium hydroxide led to the first access to 3-methylisoguanosine (19c). Although 3-methylisoguanosine (19c) proved to undergo hydrolysis at the N-glycosidic bond most slowly among the known 3-methyl-9-β-D-ribofuranosylpurines in 0.1 N hydrochloric acid at 25°C, the rate was 650 times faster than that for the unmethylated isoguanosine (3).