1-[(2R,3R,4R,5S,6R)-4,5-dihydroxy-6-(hydroxymethyl)-2-phenylmethoxyoxan-3-yl]-3,4-dimethylpyrrole-2,5-dione 、 alkaline earth salt of/the/ methylsulfuric acid 生成 [(2R,3S,4R,5R,6R)-3,4-diacetyloxy-5-(3,4-dimethyl-2,5-dioxopyrrol-1-yl)-6-phenylmethoxyoxan-2-yl]methyl acetate