Structures and absolute stereochemistry of dinapinones A1 and A2, inhibitors of triacylglycerol synthesis, produced by penicillium pinophilum FKI-3864.
During our screening program for microbial inhibitors of triacylglycerol synthesis in mammalian cells, four structurally related new compounds, dinapinones A1 (1) and A2 (2) and monapinones A (3) and B (4), were isolated from the culture broth of Penicillium pinophilum FKI-3864. Compounds 3 and 4 were produced by the fungus only when fermented in seawater-supplemented medium. The structures of 1 to 4 were elucidated by spectroscopic studies including various NMR experiments. Compounds 1 and 2 were atropisomers consisting of two monomers with the same planar structure of dihydronaphthopyranone as 3. The absolute stereochemistry of 3 was elucidated by NOE experiment and circular dichroism spectra. Furthermore, the stereochemistry of 1 and 2 was elucidated by in vitro conversion from the structure-defined 3 to its dimers 1 and 2.
Graduate School of Pharmaceutical Sciences, Kitasato University, Minato-ku, Tokyo, Japan.
Ryuji
R
Uchida
Satoshi
S
Ohte
Kyosuke
K
Kawamoto
Hiroyuki
H
Yamazaki
Mio
M
Kawaguchi
Hiroshi
H
Tomoda
D002942:Circular Dichroism; D003374:Coumarins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010407:Penicillium / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013237:Stereoisomerism; D014280:Triglycerides / Q000037:antagonists & inhibitors* / Q000096:biosynthesis*
D003374:Coumarins; D014280:Triglycerides