甲醇 、 1R-(1α,4aα,8α,8aα)-4,4a,8,8a-tetrahydro-8-methoxy-1-methyl-3-oxo-1H,3H-pyrano<3,4-c>pyran-5-carboxylic acid methyl ester 在
盐酸 作用下,
反应 2.5h,
生成
(4S,5S,6R)-5-Dimethoxymethyl-4-methoxycarbonylmethyl-6-methyl-5,6-dihydro-4H-pyran-3-carboxylic acid methyl ester 、 (2R,3R,4S,5S,6R)-5-Dimethoxymethyl-2-methoxy-4-methoxycarbonylmethyl-6-methyl-tetrahydro-pyran-3-carboxylic acid methyl ester