Formylation of glucose by cefamandole nafate at alkaline pH.

An increase in the hydrolysis rate of the formyl moiety of cefamandole nafate was observed when the commercial product was reconstituted in 5% dextrose in water relative to the rate when the formulation was dissolved in water for injection or in 0.9% saline. The increase in ester cleavage was the result of nucleophilic attack of glucose on the formyl ester moiety. This transesterification produced small amounts of D-glucose-6-formate and other D-glucose diformates. The formation of these products is of no clinical significance since the antibiotic potency and stability of cefamandole are unaffected and no toxicological differences were observed in animal studies or in clinical trials when formulated cefamandole nafate was administered with or without glucose.