Abstract

A convenient procedure has been developed for the synthesis of 3β,28-diacetoxylup-20(29)-en-30-oic acid via oxidation of 3β,28-di-O-acetylbetulin with selenium dioxide in aqueous ethanol on heating, followed by oxidation of 3β,28-diacetoxylup-20(29)-en-30-al thus formed with sodium chlorite in tert-butyl alcohol. The alkylation of 3β,28-diacetoxylup-20(29)-en-30-oic acid with 1,3-dibrompropane and 1,5-dibromopentane in boiling acetonitrile in the presence of potassium carbonate afforded the corresponding ω-bromoalkyl esters in high yields.

中文翻译：

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3,28-Diacetoxylup-20（29）-ene-30-oic acid及其ω-溴代烷基酯

摘要

一种方便的方法已经为3β的合成得到了发展，28-diacetoxylup-20（29）通过的3β氧化烯30-OIC酸28二ö -acetylbetulin在加热含水乙醇二氧化硒，随后亚氯酸钠在叔丁醇中氧化3β，28-diacetoxylup-20（29）-en-30-al的反应。在碳酸钾存在下，在沸腾的乙腈中，将1,3-二溴丙烷和1,5-二溴戊烷与3β，28-二乙酰氧基lup-20（29）-en-30-oic烷基化，得到相应的ω-溴烷基酯产量。