HCID 21500060, compound → HCID 21500059, compound

Participants

Reaction Steps

3-Chloro-3-methyl-8-oxo-7-(2-phenylacetamido)-5-thia-1-azabicyclo[4.2.0]octane-2-carboxylic acid p-nitrobenzyl ester (1.06 g, 2.1 mmoles) was hydrogenated in 60 ml of ethyl acetate over 1 g. of 10 per cent palladium on charcoal. The catalyst was filtered and washed with ethyl acetate. The filtrate was extracted with ice cold saturated sodium bicarbonate (100 ml.). The aqueous phase was covered with fresh ethyl acetate (100 ml.) and was acidified with concentrated hydrochloric acid to pH 1.5. The organic phase was separated, dried and flash concentrated to a total of 10 ml. The obtained solution was added to pentane to give 475 mg. (61 per cent yield) of the desired acid, which did not melt but slowly decomposed above 90° C., nmr (DMSO--D6) ppm (δ), 1.75 (s, 3, CH3), 3.32 (ABq, δ 0.675 ppm, J 14.2 cps, 2--CH2), ##STR9## 4.55 (s, 1, 4--H), 5.22 (2, 1, 6H), 5.51 (q, 1, 7H), 7.34 (s, 5, C6H5), 9.1 (d, 1, NH).

Provenance & Evidence