Methanesulfonyl chloride → HCID 178502809, compound

Participants

Reaction Steps

2-(2-Aminothiazol-4-yl)-2-Z-methoxyiminoacetic acid (0.018 g) in dry DMF (2 mls) under argon was cooled to -50° C. and treated successively with diisopropylethylamine (0.091 mls) and methanesulphonyl chloride (0.04 mls) for 1 h. A solution of diphenylmethyl 7β-amino-3-(E-phthalidylidenemethyl)ceph-3-em-4-carboxylate (0.222 g) in dichloromethane (3 mls) and pyridine (0.035 mls) was added to the activated intermediate at -50° C. and the solution then allowed to warm slowly to room temperature. The solution was diluted with dichloromethane and washed with water and brine, and then dried. After removal of solvent, the crude product was purified by flash chromatography on silica gel, eluting with ethyl acetate. The title compound was obtained as a yellow amorphous solid, (0.051 g), 17%), νmax (CH2Cl2) 1780(s), 1720(w), 1680(w), 1600(w), 1520(w br) and 1365cm-1 ; δH (CDCl3) 3.59 (2H,ABq,J18.6Hz), 4.09 (3H,s), 5.28(1H,d,J4.9Hz), 5.48 (2H,br.s, exch.), 6.20 (1H,dd,J4.9,8.9Hz; collapses to d on D2O shake, J4.9Hz), 6.42 (1H,s), 6.83 (1H,s), 6.88(1H,s), 7.22 (10 H,m), 7.4-7.6 (3H,m), 7.86 (1H,m) and 7.98 (1H,d,J8.9Hz, exch.); [mass spectrum: +ve ion (3-NOBA, Na+) MNa+, 716].

Provenance & Evidence