Dimethyl Sulfoxide → (6R)-7-[[(2Z)-2-(2-amino-1,3-thiazol-4-yl)-2-methoxyiminoacetyl]amino]-3-[(2-formyl-[1,3]thiazolo[4,5-c]pyridin-3-ium-3-yl)methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate

Participants

Reaction Steps

A mixture of 2-formylthiazolo[4,5-c]pyridine (85 mg, 0.5 mmole) and diphenylmethyl 7-[(Z)-2-methoxyimino-2-(2-tritylaminothiazol-4-yl)acetamido]-3-iodomethyl-3-cephem-4-carboxylate [VIIa] (466 mg, 0.5 mmole) in 5 ml of ethyl acetate containing 2 drops of DMSO was allowed to stand overnight at room temperature and then diluted with ether to give 418 mg of crude quaternary salt. The salt was treated with 3 ml of TFA and 3 drops of anisole at room temperature for 30 minutes. The mixture was concentrated in vacuo and triturated with ether to give 283 mg of powder, which was purified by a column of packing (20 ml) in PrepPAK/C18 cartridge (for Water's System 500) using 200 ml of water and 5% aqueous CH3OH (200 ml) as eluants to give 55 mg (20%) of the title compound Iw. Mp. 135°~139° C. (dec.). Estimated purity by HPLC: 55%.

Provenance & Evidence