Kukolja S, Pfeil J L, Draheim S E, Ott J L
J Med Chem. 1985 Dec;28(12):1903-6. doi: 10.1021/jm00150a024.
The methyl and isopropyl esters of (RS)-3-benzothienylglycine were resolved with (+)- and (-)-tartaric acid in acetonitrile to give the corresponding R and S salts. The R-salt 4 was hydrolyzed to (R)-3-benzothienylglycine (5). The amino group in 5 was protected with the Boc function and the protected R amino acid 6 coupled with the p-NB ester of 7-ADCA to give the diprotected cephalosporin 7. After removal of the Boc and p-NB groups, the R isomer of 7-(3-benzothienylglycylamido)deacetoxycephalosporanic acid (1) was obtained. The p-NB ester of epimeric cephalosporin 7 was separated by preparative chromatography into R and S isomers. After removal of the protective groups, the S epimer was isolated. The comparison of antibacterial activity of the R and S epimers and the RS mixture of cephalosporin 1 is reported.
将（RS）-3-苯并噻吩基甘氨酸的甲酯和异丙酯与（+）-和（-）-酒石酸在乙腈中拆分，得到相应的R盐和S盐。R盐4水解得到（R）-3-苯并噻吩基甘氨酸（5）。5中的氨基用Boc官能团保护，得到受保护的R氨基酸6，其与7-氨基脱乙酰头孢烷酸（7-ADCA）的对硝基苯酯偶联，得到双保护的头孢菌素7。去除Boc和对硝基苯基团后，得到7-（3-苯并噻吩基甘氨酰胺基）去乙酰氧基头孢烷酸（1）的R异构体。通过制备色谱法将差向异构头孢菌素7的对硝基苯酯分离为R异构体和S异构体。去除保护基团后，分离出S差向异构体。报道了头孢菌素1的R和S差向异构体以及RS混合物的抗菌活性比较。
