Structure and Synthesis of New Anticoccidial Antibiotics Isolated from Streptomyces Auranticolor

The structures of two new anticoccidial antibiotics, WS-5995A and B, produced by Streptomyces auranticolor, were determined as I and II, respectively, on the basis of spectral and chemical evidence.WS-5995A (I), having 5H-benzo[d]naphtho[2,3-b]pyran as its mother skeleton, was synthesized by coupling the diazonium salt prepared from the anthranilic acid (IX) to 3-hydroxy juglone (VIII).