Trifluoroacetic acid → HCID 178461493, compound

Participants

Reaction Steps

To a solution of (3S)-trans-3-[(E)-2-(2-thienyl)-2-{1,3-di(t-butoxycarbonylamino)-prop-2-oxyimino} acetamido]-4-methyl-2-oxoazetidine-1-sulfonic acid, potassium salt (step 4, Example 2, 4.04 gm, 5.2756 mmol) in methylene chloride (12 ml) cooled to -5° C. was added trifluoroacetic acid (18 gm, 156.890 mmol) dropwise and stirred at this temperature for 4 hr. The mixture was diluted with methylene chloride and concentrated under reduced pressure to give a foam which was triturated with ether to afford a white solid. Purification of the product over HP-20 column with acetonitrile-water (1:9) as eluant and freeze-drying of the desired fractions gave the target compound as a white solid, 2.15 gm (66% yield). 1H-NMR (DMSO-d6): δ 9.04 (d, 1H, J=8.05 Hz); 7.96-8.05 (m, 8H); 7.24 (t, 1H, J=4.5 Hz); 4.70-4.90 (m, 1H); 4.53 (dd, 1H, J=2.68 and 8.04 Hz); 3.70-3.84 (m, 1H); 3.18-3.40 (m, 4H); 1.44 (d, 3H, J=6.07 Hz).

Provenance & Evidence