An Improved Synthetic Method for<i>dl</i>-Griseofulvin and Its 2′-<i>S</i>-Analogue
作者:Masatoshi Yamato、Yasuo Takeuchi、Hideo Tomozane
DOI:10.1055/s-1990-26942
日期:——
An improved synthetic method for dl-giseofulvin (4) and its 2′-S-analogue 8 has been developed. 7-Chloro-4,6-dimethoxy-2-[5-methoxy-1-methylthio-3-oxohexylidene]-3 (2H)-benzofuranone (7), prepared by reaction of the corresponding 3 (2H) -benzofuranone with 1,1-bis(methylthio)-5-methoxy-1-hexen-3-one (6), undergoes stereoselective intramolecular cyclization when treated with activated alumina in refluxing diethyl ether. The product, the 2′-S-analogue of dl-griseofulvin 8, is converted to dl-griseofulvin (4) in good yield.
开发了一种改进的 dl-giseofulvin (4) 及其 2'-S-类似物 8 的合成方法。 7-氯-4,6-二甲氧基-2-[5-甲氧基-1-甲硫基-3-氧亚己基]-3(2H)-苯并呋喃酮(7),由相应的3(2H)-苯并呋喃酮与1反应制备,1-双(甲硫基)-5-甲氧基-1-己烯-3-酮(6),在回流乙醚中用活性氧化铝处理时发生立体选择性分子内环化。该产物是 dl-灰黄霉素 8 的 2'-S-类似物,以良好的收率转化为 dl-灰黄霉素 (4)。