Structure and total synthesis of fungal calpinactam, a new antimycobacterial agent.
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.
Koyama
Nobuhiro
N
Graduate School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.
Kojima
Shigenobu
S
Fukuda
Takeo
T
Nagamitsu
Tohru
T
Yasuhara
Tadashi
T
Omura
Satoshi
S
Tomoda
Hiroshi
H
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
D000900:Anti-Bacterial Agents; D009842:Oligopeptides; C547263:calpinactam; D002209:Caprolactam