CEPHABACINS, NEW CEPHEM ANTIBIOTICS OF BACTERIAL ORIGIN

III. STRUCTURAL DETERMINATION

Abstract

The structures of 15 new cephem antibiotics, cephabacin F_1-9 and H_1-6, were determined by their spectroscopic analyses and decomposition studies. They are consisted of a cephalosporin nucleus and a di, tri or tetrapeptide including a new amino acid which is bound at the position 3 with an ester bond. The components, F_1-9, showed unique biological activities by the presence of a formylamino group at the position 7.