Hydrochloric Acid → (6R,7R)-7-[[(2Z)-2-(2-amino-1,3-thiazol-4-yl)-2-hydroxyiminoacetyl]amino]-8-oxo-3-[(5-oxo-2H-furan-4-yl)methylsulfanyl]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid

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Reaction Steps

Diphenylmethyl 3-(2,5-dihydro-2-oxofuran-3-ylmethylthio)-7β-[2-(2-tritylaminothiazol-4-yl)-2-(Z)-trityloxyiminoacetamido]ceph-3-em-4-carboxylate (422 mg) was completely dissolved in 98-100% formic acid (3.7 ml) and then treated with 1.0M hydrochloric acid (370 μl). After stirring at room temperature for 45 mins. a drop of concentrated hydrochloric acid was added and stirring continued for 1 hour. The solvent was removed and then toluene was twice evaporated from the residue. The residue was triturated with ether and the resulting solid collected and washed with ether. Suspension of the solid in water was followed by adjustment of the pH to 2.6 with 0.1M sodium hydroxide. Care was taken to allow time for pH equilibration between additions of alkali. The solid was filtered, washed with cold water and dried in vacuo to give the title compound as an amorphous solid (87 mg). υmax (KBr disc) 1775 and 1750cm-1 ; δH [(CD3)2SO] 3.57-3.84 (4H, m), 4.85 (2H, s), 5.16 (1H, d, J 4.7Hz), 5.73 (1H, dd, J 8.3Hz, 4.7Hz), 6.67 (1H, s), 7.16 (2H, bs), 7.57 (1H, s), 9.48 (1H, d, J 8.3Hz), 11.30 (1 H, bs). [mass spectrum: +ve ion (thioglycerol) MH+ 498].

Provenance & Evidence