申请人:Pfizer Inc.
公开号:US04376204A1
公开(公告)日:1983-03-08
Processes for the preparation of the antiinflammatory agent piroxicam and intermediates leading thereto, the first of which comprises reacting N-methylsaccharin with (N-2-pyridyl)haloacetamides and alkyl haloacetates in the presence of a metal hydride to give, respectively, piroxicam and alkyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxides, intermediates which can be converted into piroxicam; and the second of which comprises reacting a novel alkyl 2-(2-methyl-3-hydroxy2,3-dihydro-1,2-benzisosulfonazol-3-yl)-2-haloacetate with a metal hydride to give alkyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxides, intermediates leading to piroxicam.
制备抗炎药哌曲酸及其中间体的过程,第一步包括将N-甲基糖精与(N-2-吡啶基)卤代乙酰胺和烷基卤代乙酸酯在金属氢化物存在下反应,分别得到哌曲酸和烷基4-羟基-2-甲基-2H-1,2-苯并噻嗪-3-羧酸酯1,1-二氧化物,这些中间体可以转化为哌曲酸;第二步包括将一种新型的烷基2-(2-甲基-3-羟基2,3-二氢-1,2-苯并异噻唑-3-基)-2-卤代乙酸酯与金属氢化物反应,得到烷基4-羟基-2-甲基-2H-1,2-苯并噻嗪-3-羧酸酯1,1-二氧化物,这些中间体可用于制备哌曲酸。