Reference

Studies on the enzymic synthesis of cephalexin

Studies on the enzymic synthesis of cephalexin. II. Separation and purification. Li, Mingyun; Xu, Jingdi; Zhao, Yuxiu; Xiong, Zhenping (Shanghai Inst. Pharm. Ind., Shanghai, Peop. Rep. China). Yiyao Gongye, (12), 1-5 (Chinese) 1984. CODEN: YIGODN. DOCUMENT TYPE: Journal CA Section: 16 (Fermentation and Bioindustrial Chemistry) 7-Aminodeacetyoxycephalosporanic acid (I) [22252-43-3] and D-phenylglycine Me ester [24461-61-8] were reacted at 15°, pH 6.7, in presence of immobilized Escherichia coli UR160 to produce cephalexin (II) [15686-71-2]. Reaction mixts. were then acidified, and subjected to CAD-40 microporous resin column chromatog. with H2O followed by 0.3N H2SO4-75% MeCN-H2O elution. Unreacted I and D-phenylglycine were recovered from aq. eluate. H2SO4-MeCN eluate was adjusted to pH 4.6-4.8 with triethylamine, refrigerated overnight, and then filtered to obtain II crystals. Recovery and quality of II were satisfactory.

Cellulose triacetate as an embedding agent for penicillin acylase producing cells of Escherichia coli

Cellulose triacetate as an embedding agent for penicillin acylase producing cells of Escherichia coli. Kou, Xiufen; Wang, Zhengxiang (Inst. Microbiol., Acad. Sin., Beijing, Peop. Rep. China). Weishengwuxue Tongbao, 11(4), 151-3 (Chinese) 1984. CODEN: WSWPDI. ISSN: 0253-2654. DOCUMENT TYPE: Journal CA Section: 16 (Fermentation and Bioindustrial Chemistry) Cellulose triacetate [9012-09-3] (1 g) was dissolved in 20 mL CHCl3, mixed with 16 g wet cells of penicillin acylase [9014-06-6]-producing E. coli AS 1.76, then squeezed through a small bore into toluene. Spherical granules (~2 mm diam.) obtained were treated with CHO(CH2)3CHO for 1 h, washed, and packed in a column. Phenylacetyl-7-aminodeacetoxycephalosporanic acid (I) [27255-72-7] (5% soln., pH 7.7) was recycled through the column at 37°. After 3 h, >95% I was transformed to 7-aminodeacetoxycephalosporanic acid (II) [22252-43-3]. After 44 days operation for 40 batches of I, II prodn. rate remained const.; av. II recovery was 78% and purity was 95%.