苷类酸催化水解的机制是
A.苷键原子先质子化,然后与苷元之间键断裂生成阳碳离子,再溶剂化成苷元
B.苷原子先质子化,然后与糖之间的键断裂生成阳碳离子,再溶剂化成糖
C.苷原子与苷元之间键先断裂生成阳碳离子,然后质子化,再溶剂化成苷元
D.苷原子与糖之间的键先断裂生成阳碳离子,然后质子化,再溶剂化成糖
E.以上均不正确

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