Entecavir was synthesized from(1S,2S,3S,5S)-3-benzyloxy-5-[6-benzyloxy-2-(tritylamino)9H-purin-9-yl]-2-(benzyloxymethyl)-cyclopentanol by oxidation with TEMPO/I2in the presence of NaHCO3,and methylenation with Mg/TiCl4/DCM/THF to give(1S,3R,4S)-N-triphenylmethyl-6-benzyloxy-9-[[2-methylene-4benzyloxy-3-(benzyloxy)methyl]cyclopentyl]-9H-purin-2-amine(4),which was subjected to deprotection with BCl3/ MeOH/H2O with an overall yield of about 44%.
{"title":"Synthesis of Entecavir","authors":"Y. Liping","doi":"10.1055/s-0033-1339524","DOIUrl":"https://doi.org/10.1055/s-0033-1339524","url":null,"abstract":"Entecavir was synthesized from(1S,2S,3S,5S)-3-benzyloxy-5-[6-benzyloxy-2-(tritylamino)9H-purin-9-yl]-2-(benzyloxymethyl)-cyclopentanol by oxidation with TEMPO/I2in the presence of NaHCO3,and methylenation with Mg/TiCl4/DCM/THF to give(1S,3R,4S)-N-triphenylmethyl-6-benzyloxy-9-[[2-methylene-4benzyloxy-3-(benzyloxy)methyl]cyclopentyl]-9H-purin-2-amine(4),which was subjected to deprotection with BCl3/ MeOH/H2O with an overall yield of about 44%.","PeriodicalId":10232,"journal":{"name":"中国医药工业杂志","volume":"114 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73626653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}