Micacocidin A, B and C, novel antimycoplasma agents from Pseudomonas sp. II. Structure elucidation.

Metal-containing novel heterocyclic antibiotics, micacocidin A (1), B (2), and C (3) have been isolated from the culture filtrate of Pseudomonas sp. No. 57-250. The structure and absolute configuration of micacocidin A, an octahedral Zn2+ complex, was determined by X-ray crystallographic analysis. And then, the structures of the two congeners, micacocidin B (Cu2+ complex) and C (Fe3+ complex) were investigated by employing one dimensional and two dimensional homonuclear and heteronuclear NMR spectroscopies and mass spectrometry.