Hydrochloric Acid → HCID 178460821, compound

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A solution of diphenylmethyl 3-bromomethyl-7β-(2-thienylacetamido)-ceph-3-em-4-carboxylate (11.67g) and 1-ethyltetrazoline-5-thione (2.6g) in dry tetrahydrofuran (150ml) was stirred at 0° and a solution of triethylamine (2.8ml) in tetrahydrofuran (25ml) was added, dropwise, over 5 minutes. The resulting suspension was stirred for a further 25 minutes, during which time the temperature was allowed to rise to ca. 20°, and was then added, over 5 minutes, to a stirred mixture of 2N-hydrochloric acid (50ml), water (350ml), brine (350ml), and ethyl acetate (600ml). The organic phase was separated, and washed with 2N-hydrochloric acid, saturated sodium bicarbonate, water, and brine, and dried and evaporated to a foam (11.71g). A solution of this foam in benzene (25ml) was purified by chromatography on kieselgel (200g), with benzene:ethyl acetate = 5:1 as eluant. Appropriate fractions were combined and the solvents evaporated in vacuo. The residue was dissolved in methylene dichloride, and the solution run into petroleum ether to give the ester as a pale-yellow, amorphous solid (8.585g, 68 %); [α]D23 -131° (c 0.97, CHCl3); λmax. (EtOH) 264 nm (ε 7,300), τ (CDCl3) values include 4.12 (7-H, dd, J 5 and 9 Hz.), 5.04 (6-H, d, J 5 Hz.), 5.83 (CH3CH2 -, q, J 7 Hz.), and 8.57 (CH3CH2 -, t, J 7 Hz.).

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