Thiazolo[4,5-c]pyridine → (6R)-7-[[(2Z)-2-(2-amino-1,3-thiazol-4-yl)-2-(1-carboxycyclobutyl)oxyiminoacetyl]amino]-8-oxo-3-([1,3]thiazolo[4,5-c]pyridin-5-ium-5-ylmethyl)-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate

Participants

Reaction Steps

To a solution of diphenylmethyl 7-[(Z)-2-(1-t-butoxycarbonylcyclobut-1-oxyimino)-2-(2-tritylaminothiazol-4-yl)-acetamido]-3-iodomethyl-3-cephem-4-carboxylate [VIIe'] (482 mg, 0.45 mmole) in 2 mL of DMSO was added thiazolo[4,5-c]pyridine (68 mg, 0.5 mmole) in one portion. The mixture was stirred for 45 minutes at room temperature. The reaction mixture was then diluted with ether (50 mL) and the precipitated oil was triturated in ether (4×50 mL). The precipitate was mixed with anisole (0.5 mL), trifluoroacetic acid (5 mL) and water (0.5 mL), and the mixture was stirred with ice cooling for 30 minutes and at room temperature for 1 hour, and then was concentrated under reduced pressure (<30° C.). The residue was triturated with isopropyl ether (100 mL), and the resulting precipitate was collected by filtration to afford 395 mg of crude title compound, as a yellow powder. The crude product (387 mg) was purified on an HP-20 column (100 mL). The eluate containing desired product, which was eluted with 50% methanol, was concentrated and lyophilized to give 80 mg (31%) of the title product (Ie) as a pale yellow amorphous powder. Mp >170° C. (dec.).

Provenance & Evidence