3β,28-Diacetoxylup-20(29)-en-30-oic acid (obtained via oxidation of betulin diacetate) enters the addition reaction with P—H-phosphonium salts (triarylphosphonium trifluoroacetates) under mild conditions to afford β-carboxyalkylphosphonium salts. Structure and composition of the resulting compounds were confirmed by NMR and IR spectroscopy, mass spectrometry, and elemental analysis.

中文翻译：

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3,28-diacetoxylup-20(29)-en-30-oic酸的C-29-鏻衍生物的合成

3β,28-Diacetoxylup-20(29)-en-30-oic酸（通过二乙酸桦木醇氧化获得）在温和条件下与P-H-鏻盐（三芳基鏻三氟乙酸盐）发生加成反应，得到β-羧基烷基鏻盐。所得化合物的结构和组成经核磁共振和红外光谱、质谱和元素分析证实。