Improvements in or relating to novel antibiotics and the manufacture thereof

摘要

Antibiotics sparsomycin and sparsomycin A are produced by cultivating Streptomyces sparsogenes var. sparsogenes (NRRL 2940, NCIB 9449) in an aqueous nutrient medium under aerobic conditions until substantial antibiotic activity is imparted to the medium. The two antibiotics may be recovered from the medium by contacting it with a capillary adsorbent such as decolorizing carbon or a decolorizing resin, eluting the adsorbent with an acidified water-miscible solvent such as acetone or methyl or ethyl alcohol, and then separating the antibiotics by fractional liquid-liquid extraction. Sparsomycin is an acidic substance which is slightly soluble in water and lower alcohols and insoluble in less polar organic solvents, has a pKa1 of 8.6-9.0 in water and an equivalent weight of 356, shows ultra-violet absorption maxima in water and 0.01 N e.g. H2SO4 at 270mm and 301.5 mm and in 0.01 N aq. KOH at 236 mm , 284 mm and 328 mm , has an optical rotation [a ]25D+69 DEG (C=0.756, in water), has a calculated empirical formula C13H21N3O6S2 with elemental analysis C 40.91%, H 5.65%, N 11.38% and S 16.95%, and exhibits a characteristic infra-red absorption spectrum as shown in Fig. 2. Sparsomycin A is a basic substance which is slightly soluble in water and lower alcohols and insoluble in acetone, ethyl acetate, chloroform, benzene and petroleum ether, has a pKa1 of 5.07 in water and an equivalent weight of 269, has an optical rotation [a ]25D-62 DEG (C=0.718 in 0.1N HCl), shows ultra-violet absorption maxima in water and 0.01 N KOH at 270 mm and in 0.01 N H2SO4 at 227 mm and 271 mm , has a calculated empirical formula C11H14O4N4 with elemental analysis C 49.81%, H 5.20% and N 20.92%, and exhibits a characteristic infra-red absorption spectrum as shown in Fig. 3.