title: Structure and total synthesis of fungal calpinactam, a new antimycobacterial agent.
abstract: A new fungal metabolite designated calpinactam (1) was isolated from the culture broth of Mortierella alpina FKI-4905, and its structure was elucidated by spectroscopic analyses including NMR experiments. Calpinactam was found to be a hexapeptide with a caprolactam ring at its C-terminal. Its absolute stereochemistry was determined by amino acid analysis and total synthesis. Calpinactam selectively inhibited the growth of mycobacteria among various microorganisms. The MIC values of calpinactam against Mycobacterium smegmatis and M. tuberculosis were 0.78 and 12.5 microg/mL, respectively.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Koyama
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Kojima
authors.forename: Takeo
authors.initials: T
authors.lastname: Fukuda
authors.forename: Tohru
authors.initials: T
authors.lastname: Nagamitsu
authors.forename: Tadashi
authors.initials: T
authors.lastname: Yasuhara
authors.forename: Satoshi
authors.initials: S
authors.lastname: Omura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tomoda
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D002209:Caprolactam / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D020094:Mortierella / Q000737:chemistry; D020102:Mycobacterium smegmatis / Q000187:drug effects*; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D019906:Nuclear Magnetic Resonance, Biomolecular; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D009842:Oligopeptides; C547263:calpinactam; D002209:Caprolactam