申请人:Bartra Sanmartí Martí
公开号:US20130296558A1
公开(公告)日:2013-11-07
It comprises a preparation process of entecavir comprising: submitting a (1S,3R)-3-(tert-butyldimethylsilyloxy)-1-(oxiran-2-yl)pent-4-yn-1-ol (VIII) to a double esterification and to a radicalary cyclization, yielding a compound of formula (V), where either a compound of formula (VIII) is submitted to a first esterification reaction, then to a catalytic radicalary cyclization using titanocene dichloride as catalyst in the presence of Mn/2,4,6-collidine HCl or Zn/2,4,6-collidine/trimethylsilyl chloride, and finally to a second esterification reaction or, alternatively, the compound of formula (VIII) is submitted first to a catalytic radicalary cyclization, and then to an esterification reaction. Entecavir can be obtained by submitting compound (V) to a desilylation reaction to remove the TBS group and then to a Mitsunobu coupling with 2-amino-6-chloroguanine, followed by hydrolysis. It also relates to some new intermediates of the process.
该方法包括恩替卡韦的制备过程,包括将(1S,3R)-3-(叔丁基二甲基硅氧基)-1-(环氧戊-2-炔-1-基)戊-4-烯-1-醇(VIII)进行双酯化和自由基环化,得到式(V)的化合物,其中化合物(VIII)可以先经过第一次酯化反应,然后在Mn/2,4,6-哌啶盐酸盐或Zn/2,4,6-哌啶/三甲基氯硅烷的存在下,使用二氯化钛作为催化剂进行催化自由基环化,最后再进行第二次酯化反应,或者化合物(VIII)可以先进行催化自由基环化,然后再进行酯化反应。通过将化合物(V)经过去除TBS基团的脱硅反应,然后与2-氨基-6-氯鸟嘌呤进行Mitsunobu偶联,最后进行水解反应,可以得到恩替卡韦。该方法还涉及该过程的一些新中间体。