SN2Displacement of Carbohydrate Triflates by 9-Oximes of Erythromycin A and Of a Tylosin Derivative
摘要:
The preparation of 9-O-glycosyloxime derivatives of erythromycin A (1) and tylosin (2) is reported. Access to this new class of macrolides was achieved from (E)-9-oxime of erythromycin A (3) and 9-oxime of tylosin 20-(1,3-dithiane) (4), by successful displacement of triflates of suitably protected carbohydrates.
α-Hydrogen elimination in some carbohydrate triflates
作者:Ahmed El Nemr、Tsutomu Tsuchiya
DOI:10.1016/0040-4039(95)01607-j
日期:1995.10
In somecarbohydrate triflates, treatment with MeLi (or BuLi) in ether caused α-hydrogen elimination initially, then the resulting carbanion is stabilized to give either C-methyl(or butyl)-hydroxy derivatives or unsaturated products.