Acetic Acid → Cephaloridine

Participants

Reaction Steps

3-Dichloroacetoxymethyl-7β-(2'-thienylacetamido)ceph-3-em-4-carboxylic acid (0.1 g., 2.15 mmole.) was suspended in water (4 ml.), and pyridine (0.352 ml., 4.3 mmole.) was added. The solution was heated at 50° for 1 hour, acidified to pH 4.5 with acetic acid, and washed with ethyl acetate and finally with petrol. The aqueous solution was freed from dissolved organic solvents and applied to a column comprising (from top to bottom) layers of deactivated neutral alumina (8 ml.), Dowex 1 (AcO-) (20 ml.) and Zeokarb 226 (H+) (5 ml.). Elution with water was carried out until the eluate showed no optical rotation; the total eluate was freeze-dried and the residue triturated with methanol to give a white solid (296 mg.), [α]D23 +48.8° (c 0.8, water), λλmax (water) 238nm (E1cm1% = 351), 255 nm (E1cm1% = 324).

Provenance & Evidence