Reacción #56574

Ecuación de reacción

2,2,2-trichloroethyl 2-methyl-7-[2-hydroxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-cephem-4-carboxylate

2,2,2-trichloroethyl 2-methyl-7-[2-hydroxyimino-2-(2-imino-2,3-dihydrothiazol-4-yl)acetamido]-3-cephem-4-carboxylate

diazomethane

→

2,2,2-trichloroethyl 2-methyl-7-[2-methoxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-cephem-4-carboxylate

Disolventes

diethyl ether

dioxane

Condiciones de reacción

Tratamiento posterior

1. 1
   ConcentraciónAfter the reaction mixture was concentrated
2. 2
   Filtracióncollected by filtration
3. 3
   Otrodried

Procedimiento

To a solution of 2,2,2-trichloroethyl 2-methyl-7-[2-hydroxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-cephem-4-carboxylate (syn isomer), which can be represented as 2,2,2-trichloroethyl 2-methyl-7-[2-hydroxyimino-2-(2-imino-2,3-dihydrothiazol-4-yl)acetamido]-3-cephem-4-carboxylate (syn isomer), (125 mg.) in dioxane (5 ml.) was added dropwise 0.1 M solution of diazomethane in diethyl ether till the starting compound disappeared. After the reaction mixture was concentrated, the residue was pulverized in diethyl ether, collected by filtration and then dried to give brown powder of 2,2,2-trichloroethyl 2-methyl-7-[2-methoxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-cephem-4-carboxylate (syn isomer), which can be represented as 2,2,2-trichloroethyl 2-methyl-7-[2-methoxyimino-2-(2-imino-2,3-dihydrothiazol-4-yl)acetamido]-3-cephem-4-carboxylate (syn isomer), (110 mg.), mp 128° to 149° C. (dec.).

Fuente