Pyrazole → HCID 131710130, compound

Participants

Reaction Steps

3-Dichloroacetoxymethyl-7β-(2'-thienylacetamido)ceph-3-em-4-carboxylic acid (3.2 g., 6.9 mmole.) was dissolved in 50%-aqueous acetone (60 ml.). and treated with pyrazole (1.6 g., 24 mmole.), and the solution heated at 50° for 35 minutes. The acetone was removed under reduced pressure, and the aqueous residue was extracted with ether (9 × 20 ml.). After drying, the ether was evaporated and the solid residue recrystallised from aqueous alcohol (1.3 g., 47%), mp. 180°-185° (decomp) [α]D30 = 53.5° (c 1.01, ethanol), λmax (ethanol) 236 nm. (β 14,000), 261 nm. (ε = 8,250) (shoulder), νmax (Nujol) 3272 (--NH), 1773 (β-lactam), 1712 (--COOH), 1660 and 1532 cm-1 (--CONH--). (Found: C, 50.9; H, 4.2; N, 13.9; S, 15.7. C17H16N4S2O4 requires C, 50.5; H, 4.0; N, 13.9; S, 15.9%). N.M.R. (D2O, with NaHCO3) 2.30, 3.62, 2.41τ (-N-CH=CH-CH=N), Rf 0.37 (Systems B), 0.12 (System C).

Provenance & Evidence