STUDIES ON NEW CATECHOL CONTAINING CEPHALOSPORINS .1. SYNTHESIS AND STRUCTURE-ACTIVITY-RELATIONSHIPS OF CEPHALOSPORINS HAVING A CATECHOL MOIETY AT THE C-3 POSITION - CHOI, KI; CHA, JH; PAE, AN; CHO, YS; KANG, HY; KOH, HY; CHANG, MH (JAPAN ANTIBIOT RES ASSN, 1995)