S-2-Benzothiazolyl 2-amino-alpha-(methoxyimino)-4-thiazolethiolacetate

Brief introduction

AE-active ester, chemical title 2-methoxyimino-2-(2-amino-4-thiazolyl)-(z)-thioacetic acid benzothiazole ester. Appearance: white or mild yellow crystalline powder, melting factor 128130 °C. Low toxicity and bitter taste, soluble in acetone, tetrahydrofuran, barely soluble in acetonitrile, dichloromethane, insoluble in water, and can be burned in case of open flame.

apply

AE-active ester is one of the essential facet chains of semi-synthetic cephalosporin antibiotic drugs, and is an imperative intermediate for the synthesis of third- and fourth-generation semi-synthetic cephalosporins such as cefotaxime sodium, ceftriaxone sodium, cefpime, cefpiro, etc.

apply

AE-active ester is an ester derivative, which can be used as the foremost uncooked fabric for the manufacturing of cefttriazine, cefotaxime sodium and different drugs.

preparation

In a 500ml four-mouth flask geared up with mechanical stirring, a consistent stress losing funnel, a reflux condenser tube and a thermometer, add 20g (0.0995mol) of ammothiazome acetic acid, add dibenzothiazolethiazole thioether, pyridine and 100ml of dichloromethane in proportion, begin stirring, slowly add 80ml of triphenylphos dichloromethane answer dropwise beneath room temperature and lively stirring, add it, stir the response at a temperature of 20~25 °C for 3h (t1), cool in an ice bath, filter, wash the filter cake with methanol, vacuum drying, 29.1g (0.08314mol, theoretical cost of 0.0995mol) of AE-active ester used to be obtained, the yield used to be 83.6%, and the content material used to be 98.6% (LC); Under full of life stirring of the filtrate, slowly add 50ml of dichloromethane answer of bis(trichloromethyl) carbonate dropwise, add it, proceed the response at 20~25 °C for three hours (t2), after the reaction, filter, filter cake washed with methanol, and attain 16.6g of dibenzothiazole thioether (0.05mol, the theoretical cost is the sum of the quantity recovered and the quantity now not collaborating in the reaction, right here it have to be 0.0995×1.2-0.0995+0.0995/2=0.07mol), The yield used to be 71.43%, the content material was once 98.1% (LC), the filtrate used to be concentrated, and the methanol used to be recrystallized to acquire 22.9g (0.0874mol, theoretical price of 0.1194mol), the yield was once about 73.2%, and the content material used to be 98.3% (LC).