Sulfoxides protective role

In view of the important role of the 3 -hydroxyl group in the mechanism of inactivation by resistant bacteria (see p. 165), Hanessian and co-workers prepared 3 -epiparomamine. The already mentioned derivative of paromamine (156, see p. 159) was oxidized with methyl sulfoxide-acetic anhydride to give a glycos-3 -ulose derivative, which, by borohydride reduction and removal of the protecting groups, led to 215. 

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