反应详情

To an ice cold solution of t-butyl 3-acetoxymethyl-7β-aminoceph-3-em-4-carboxylate (1.59 g) and propylene oxide (3.5 mls) in ethyl acetate (15 mls) was added with stirring a 1-M solution of 2-dichloroacetoxyamino-2-(thien-3-yl) acetyl chloride (syn-isomer) (5.3 ml.) in ethyl acetate. After 11/2 hrs. at 20° C. the solution was washed with 2N-HCl, saturated sodium bicarbonate solution and brine. The organic layer was dried and evaporated to give t-butyl 3-acetoxymethyl-7β-[2-dichloroacetoxyimino-2-(thien-3-yl)acetamido]ceph-3-em-4-carboxylate (syn-isomer) as a white foam, (2.8 g, 100%), [α]D +47.0° (c 0.9, DMSO), λmax. (ethanol) 253 nm (ε 13,900), νmax. (CHBr3) 3580 (OH), 3410 (NH), 1790 (β-lactam), 1728 (OCOCH3), 1720 (COO But) and 1700 and 1520 cm.-1 (CONH); τ (CDCl3) values include 2.11 to 2.7 (m; thienyl protons), 7.92 (s; OCOCH3), 8.48 (s; But).

1. custom2 hrs
2. washat 20° C. the solution was washed with 2N-HCl, saturated sodium bicarbonate solution and brine
3. customThe organic layer was dried
4. customevaporated