| 摘要 |
NEW MATERIAL:An antibiotic substance istamycin A (acid addition salt) of formulaIhaving the following properties: (l) Basic substance. Its carbonate is white powder. (2) Exhibits no definite melting point. (3) Specific rotatory power: [alpha]D<25>=+131 deg. (C=1.0, water). (4) Soluble in methanol, and slightly soluble in ethanol. (5) Positive to the ninhydrin and Rydon-Smith reactions. USE:An antimicrobial agent against Gram-positive and Gram-negative bacteria. PROCESS:A strain, e.g. Streptomyces tenjimariensis-SS939 strain (FEMR-P No. 4932), of the genus Streptomyces, is cultivated, and istamycins C and CO are collected with istamycins A and B which are principal components in the culture fluid. The resultant istamycins C and CO are then purified and separated. The istamycin CO is a novel substance, expressed by formula II or III, and having a weak antimicrobial activity thereof, but can be easily converted into the istamycin C (by converting the methylamino group at 4-position into an N-glycyl group). |
