合成高硫胺糖醇缩醛(II),[3-(4'-氨基-2'-甲基-嘧啶基-(5')-甲基)-4-甲基-5-(β,γ-二氧丙基)-噻唑氯-盐酸盐],二(3-)(4'-氨基-2'-甲基-嘧啶基-(5')-甲基)-4-甲基-5-烯丙基-噻唑氯盐酸盐(VIII)。Erthate Verbindung ist(nach WH Schopfer)与抗微生物剂Thiamins的组合。
Mild halogenation of stabilized ester enolates by cupric halides
摘要:
The reactions of various stabilized ester enolates of 2-keto, 2-(alkoxycarbonyl), 2-phosphoryl, and 2-(benzenesulfonyl) esters with cupric chloride or cupric bromide have been examined. The reactions lead to 2-halo esters in good to excellent yields under mild condition. Enolates which contain an unsaturated functionality such as a double bond, a triple bond, or an allylic or a benzylic moiety react with high chemoselectivity.