title: Isolation of novel antibiotics X-14667A and X-14667B from Streptomyces cinnamonensis subsp. urethanofaciens and their characterization as 2-phenethylurethanes of monensins B and A.
abstract: Antibiotics X-14667A (1) and X-14667B (2) are novel monovalent polyether antibiotics of the spiroketal type isolated from fermented cultures of Streptomyces cinnamonensis subsp. urethanofaciens together with monensin (3), its lower homolog, factor B (4) and 1,3-diphenethylurea (6). By a combination of microanalysis, mass spectrometry and 13C nmr, antibiotics X-14667A and B have been shown to be natural 2-phenethylurethanes of monensin B and A respectively. Both structures have been confirmed by reacting the appropriate monensin with 2-phenethylisocyanate to yield semi-synthetic compounds that are identical to the natural products.
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000302:isolation & purification* / Q000378:metabolism; D055598:Chemical Phenomena; D002621:Chemistry; D005663:Furans / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008985:Monensin / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D005663:Furans; C032952:X 14667B; C032951:X 14667A; D008985:Monensin