title: Isolation, structure determination and biological activities of a novel antifungal antibiotic, S-632-C, closely related to glutarimide antibiotics.
abstract: A new antifungal antibiotic, S-632-C, was extracted with ethyl acetate from the culture filtrate of Streptomyces hygroscopicus S-632 and isolated through a combination of column and preparative thin-layer chromatographies on silica gel. The structure of S-632-C was determined by analysis of 1H and 13C-NMR, MS, UV and IR spectra in comparison with those of S-632-A2 (9-methylstreptimidone). The signals were assigned on the basis of 2D NMR experiments, which involved 1H-1H DQF COSY, HMQC and HMBC spectral analysis. From these results, the chemical structure of S-632-C was elucidated as 6-(3,5-dimethyl-2-oxo-4,6-octadienyl)-4-carbamoylmethyl-3,4, 5,6-tetrahydro-2- pyrone. The antibiotic exhibited exclusively weak in vitro antifungal activity against Saccharomyces spp. and similar cytotoxic activity against KB carcinoma cells, as compared with the glutarimide antibiotic S-632-A2. In addition, this antibiotic had the ability to change the morphology of ras(ts)-transformed NRK cells to that of normal cells, also a characteristic S-632-A2 and B1.
authors.affiliation: Tokushima Research Center, Taiho Pharmaceutical Co., Ltd., Japan.
authors.forename: A
authors.initials: A
authors.lastname: Urakawa
authors.forename: T
authors.initials: T
authors.lastname: Otani
authors.forename: K
authors.initials: K
authors.lastname: Yoshida
authors.forename: M
authors.initials: M
authors.lastname: Nakayama
authors.forename: K
authors.initials: K
authors.lastname: Suzukake-Tsuchiya
authors.forename: M
authors.initials: M
authors.lastname: Hori
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D011753:Pyrones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D012440:Saccharomyces / Q000187:drug effects; D013302:Streptomyces / Q000737:chemistry / Q000378:metabolism
chemical_list: D000935:Antifungal Agents; D011753:Pyrones; C085616:antibiotic S 632-C