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 HCI 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.
它包括一种
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
丙烷-2-基)
戊-4-炔-1-醇(VIII)提交给双酯化和自由基环化,得到化合物的公式(V),其中化合物的公式(VIII)被提交给第一酯化反应,然后在Mn/2,4,6-哥林丁盐酸盐或Zn/2,4,6-哥林丁/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,最后进行第二酯化反应;或者,化合物的公式(VIII)首先被提交给催化自由基环化,然后进行酯化反应。
恩替卡韦可以通过将化合物(V)提交给去
硅反应以去除TBS基团,然后与2-
氨基-
6-氯鸟嘌呤进行三宅信夫偶联,随后进行
水解来获得。它还涉及该过程的一些新中间体。