A simple and effective method for formylation of betulin using formic acid and 3a,6a-diphenylthioglycoluril is reported. The yield of betulin diformate was 87%. Allobetulin formate (95%) was prepared by reacting betulin diformate with trifluoroacetic acid. The structures of betulin diformate and allobetulin formate were confirmed by IR and NMR spectroscopy. The antioxidant activity of the synthesized compounds was studied.

中文翻译：

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二甲酸桦木醇和甲酸别白桦醇的合成新方法及抗氧化活性

报道了一种使用甲酸和 3a,6a-二苯基巯基脲甲酰化白桦脂醇的简单有效的方法。桦木脑二甲酸酯的产率为87%。通过将桦木二甲酸酯与三氟乙酸反应制备甲酸别白桦酯 (95%)。通过红外光谱和核磁共振光谱证实了白桦脂醇二甲酸酯和别白桦脂醇甲酸酯的结构。研究了合成化合物的抗氧化活性。