摘要
Monapinones A(1)to E(5),half parts of dinapinones,were produced by fermentation of Talaromyces pinophilus FKI-3864 in seawater-containing medium and have a common dihydronaphthopyranone skeleton with a different long alkyl chain.The relative stereochemistries of 3–5 were elucidated by various NMR experiments including analysis of 1 H NMR coupling constants,ROESY and the dihedral angles.The absolute stereochemistries of 3–5 at C-3 were determined by the circular dichroism spectra in comparison to the data of(R)-and(S)-semivioxanthins(6 and 7).Accordingly,total absolute stereochemistries of 3–5 were concluded to be 3S,13R,15R,17R,19R,3S,13R,15R,17R and 3S,13R,15R,respectively.
