反应详情

To a solution of 439 mg. (0.93 mmole) of p-nitrobenzyl 7-[2-(2-thienyl)acetamido]-3-hydroxy-3-cephem-4-carboxylate in 4.4 ml. of DMF cooled in an ice bath was added dropwise 118 mg. (0.07 ml., 0.93 mmole) of oxalyl chloride. The reaction mixture was allowed to stand for 4 hours at room temperature and was then poured into a mixture of aqueous 5% hydrochloric acid and ethyl acetate. The organic layer was separated and was washed sequentially with 5% hydrochloric acid, water and a saturated solution of sodium chloride. The washed layer was dried and evaporated to dryness to yield the reaction product, p-nitrobenzyl 7-[2-(2-thienyl)acetamido]-3-chloro-3-cephem-4-carboxylate as an amorphous solid. The product was obtained crystalline by triturating the amorphous residue with ether. Yield 360 mg. The infrared spectrum and NMR spectrum of the crystalline product were consistent with the spectra of authentic material.

1. additionwas added dropwise 118 mg
2. customThe organic layer was separated
3. washwas washed sequentially with 5% hydrochloric acid, water
4. customThe washed layer was dried
5. customevaporated to dryness