Synthesis of Scopin Acetate and 6,7-Didehydrohyoscyamin. Intramolecular Phenylsulfenylation of a Nonactivated Methylene Group of EthylN-Demethyl-3-O-(phenylthio)tropine-N-carboxylate
作者:Goran B. Petrović、Radomir N. Saičić、Živorad M. Čeković
DOI:10.1002/hlca.200390258
日期:2003.9
7-didehydro-N-demethyltropine-N-carboxylate (15) as a synthetic intermediate (Schemes 3 and 5). The reaction of 9 with tributylstannane in the presence of ethyl acrylate, as a radicophilic olefin, involves Michael-type alkylation at C(6) of the tropine skeleton affording ethyl N-demethyl-N-(ethoxycarbonyl)tropine-6-propanoate (18) (Scheme 6).
乙酸scopin(6b)和6,7-二氢杂多氢嘧啶(17)的合成是通过使用Tropine(5)作为起始化合物来实现的。在六丁基二氢化锡存在下,通过辐射将(苯硫基)自由基正式转移至N-脱甲基-3 - O-(苯硫基)Tropine- N-羧酸乙酯的未活化6位(9)是该合成方法的关键步骤,涉及作为合成中间体的6,7-二氢-N-去甲基tropine - N-羧酸乙酯(15)(方案3和5)。反应9在丙烯酸乙酯(作为亲核性烯烃)存在下,用三丁基锡烷进行反应,在Tropine骨架的C(6)处进行Michael型烷基化反应,得到N-脱甲基-N - N-(乙氧基羰基)tropine-6-丙酸乙酯(18)(方案6)。