STRUCTURE DETERMINATION OF NEW ANTIFUNGAL ANTIBIOTICS, POLARAMYCINS A AND B

Antifungal antibiotics, polaramycins A and B have been isolated from the culture of Streptomyces hygroscopicus LP-93. Polaramycins A and B are 36 membered polyol macrolide antbiotics containing hemiacetal monoester of malonic acid and guanidyl groups. Based on spectral evidence including UV, IR, FABMS, ¹HNMR, ¹³CNMR, DEPT, ¹H-¹H COSY, HETCOR, HMBC, the structure of polaramycins A and B have been assigned as shown in Fig 1 (A, R=H; B, R=CH₃).