Five eudesmane-type sesquiterpene glycosides, named sonneratiosides A–E (1–5), were isolated from the leaves of Sonneratia alba (Lythraceae). The aglycone of sonneratioside A was identified as cryptomeridiol also known as proximadiol. X-ray crystallographic analysis of sonneratioside A confirmed its structure and its absolute stereochemistry. Eudesmol β-d-glucopyranoside (6) was also isolated from nature for the first time. The tyrosinase inhibitory activity was assayed for the new compounds together with seven known compounds. Among them, arbutin (12) showed the expected activity and luteolin 7-O-rutinoside (10) showed comparable activity to arbutin.

中文翻译：

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Eudesmane型倍半萜烯糖苷：sonneratioside AE和eudesmolβ-D-吡喃葡萄糖苷，来自白叶Sonneratia。

五eudesmane型倍半萜甙，命名sonneratiosides A-E（1 - 5）中，从叶分离的杯萼海桑（千屈菜科）。sonneratioside A的糖苷配基被确定为隐美二醇，也被称为Proximadiol。Sonneratioside A的X射线晶体学分析证实了其结构和绝对立体化学。桉叶醇β - d吡喃葡萄糖苷（6）也从自然界首次分离得到。测定了新化合物与七种已知化合物的酪氨酸酶抑制活性。其中，熊果苷（12）表现出预期的活性，木犀草素7- O-芸香苷（10））显示出与熊果苷相当的活性。