title: Synthesis of 2"-oxidized derivatives of 5-deoxy-5-epi-5-fluoro-dibekacin and -arbekacin, and study on structure-chemical shift relationships of urethane(or amide)-type NH protons in synthetic intermediates.
abstract: Three 2"-modified dibekacin-analogs have been prepared as potential compounds active against resistant bacteria producing 2"-O-phosphotransferases; one is 5-deoxy-5,2"-diepi-5-fluorodibekacin (9) prepared from a suitably protected 2"-O-triflyl derivative through the 2" 3"-cyclic carbamate, and the others are 2"-oxo derivatives (12 and 22, both as the hydrate) of 5-deoxy-5-epi-5-fluoro-dibekacin and -arbekacin prepared through oxidation at C-2" of suitably protected derivatives. Relationships between the t-butoxycarbonyl(= Boc)-NH-shifts of per-N-Boc synthetic intermediates and their structures were studied. It was found that the shifts, measured in pyridine-d5 at 80 degrees C, which spread over a close range (delta 6-7 ppm), are sensitively influenced by nearby and surrounding groups around the BocNH group in respect of electron-withdrawing character, hydrogen bonding (BocNH ... acceptor), and also solvent effects (BocNH ... NC5H5).
authors.affiliation: Institute of Bioorganic Chemistry, Kawasaki, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: T
authors.initials: T
authors.lastname: Tsuchiya
mesh_terms: D000577:Amides / Q000737:chemistry* / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D003982:Dibekacin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011522:Protons; D014520:Urethane / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D000577:Amides; D000900:Anti-Bacterial Agents; D011522:Protons; C088550:5-deoxy-5-fluoroarbekacin; D014520:Urethane; D003982:Dibekacin