Hydrolysis of cephalosporins in strongly acid medium.
The hydrolysis of cephalexin, cephalothin and cephaloridine in strongly acid medium (10--25% sulfuric acid) at high temperature (approximately 100 degrees C) was studied. The hydrolysis proceeds with a high rate (10--15 min are necessary for complete hydrolysis) and results in definite products with low mol.-wt. The hydrolysis under such hard conditions affects the side chain in 3-position, in some cases the C--N bond in the amido group in 7-position, and leads to a total cleavage of the beta-lactam ring, giving thiazine compounds. The reaction products were identified using IR and UV spectral data, thin-layer and gas chromatography, and some characteristic reactions of functional groups. The results of the investigation were used for development of photometric procedures for determination of cephalosporins.
Hydrolysis of cephalosporins in strongly acid medium. The hydrolysis of cephalexin, cephalothin and cephaloridine in strongly acid medium (10--25% sulfuric acid) at high temperature (approximately 100 degrees C) was studied. The hydrolysis proceeds with a high rate (10--15 min are necessary for complete hydrolysis) and results in definite products with low mol.-wt. The hydrolysis under such hard conditions affects the side chain in 3-position, in some cases the C--N bond in the amido group in 7-position, and leads to a total cleavage of the beta-lactam ring, giving thiazine compounds. The reaction products were identified using IR and UV spectral data, thin-layer and gas chromatography, and some characteristic reactions of functional groups. The results of the investigation were used for development of photometric procedures for determination of cephalosporins.