Thiazolinoazetidinone compounds are described which are useful as intermediates in the preparation of cephalosporins. They have the general formula
wherein
R is hydrogen,
methoxy,
C1-C2 alkoxycarbonyl,
C1-C8 alkyl,
C1-C8 alkyl monosubstituted with protected hydroxy, Cl-C3 alkoxy or cyano,
C2-C8 alkenyl,
C2-C8 alkenyl monosubstituted with protected hydroxy,
C1-C3 alkoxy or cyano,
C3-C8 cycloalkyl,
C3-C8 cycloalkyl substituted with protected hydroxy, C1-C3 alkoxy or cyano,
OR
R' is hydrogen, protected hydroxy, chloro, bromo, C1-C3 alkyl, C1-C3 alkoxy, nitro or cyano;
Y is oxygen or a carbon-carbon bond;
R3 is protected hydroxy, C1-C4 alkyl or protected amino;
m is 0-2;
n is 0-2;
R1 is a carboxylic acid protecting group; provided that the 1- and 5-position C-H bonds in the resulting thiazolinoazetidinone are in the a-position.
These compounds are prepared by an allylic chlorination process in which a chlorine atom is inserted on the saturated methyl group of a 3-methyl-2- but-3-enoate group attached to the thiazolinoazetidinone ring.
所述
噻唑氮杂
环丁酮化合物可用作制备
头孢菌素的中间体。它们的通式为
其中
R 是氢
甲氧基
C1-C2烷氧基羰基
C1-C8 烷基
被保护羟基、Cl-C3 烷氧基或
氰基单取代的 C1-C8 烷基、
C2-C8 烯基
C1-C8烷基、C1-C8烷基与受保护羟基、Cl-C3 烷氧基或
氰基的单取代基
C1-C3 烷氧基或
氰基的单取代基、
C3-C8 环烷基、
被保护羟基、C1-C3 烷氧基或
氰基取代的 C3-C8 环烷基、
或
R' 是氢、受保护羟基、
氯、
溴、C1-C3 烷基、C1-C3 烷氧基、硝基或
氰基;
Y 是氧或碳-碳键;
R3 是受保护的羟基、C1-C4 烷基或受保护的
氨基;
m 为 0-2;
n 为 0-2;
R1 是
羧酸保护基;条件是所得
噻唑嗪二酮中的 1 位和 5 位 C-H 键位于 a 位。
这些化合物是通过烯丙基
氯化工艺制备的,在该工艺中,一个
氯原子被插入连接到
噻唑嗪酮环上的 3-甲基-2-丁-3-烯酸酯基团的饱和甲基上。