Monascustin (1), an unusual γ-lactam, was isolated from an ethanol extract of the Monascus purpureus fermented rice. Its structure including the absolute configuration was determined by spectroscopic data analysis and confirmed by X-ray crystallography. A plausible biosynthetic pathway is discussed on the basis of amino acid derivatization. Compound 1 showed inhibitory activity against histone deacetylase 1.

Four new taraxastane-type triterpenoids acids 3β,22α-dihydroxy-20-taraxasten-30-oic acid (1), 3β-hydroxy-22-oxo-20-taraxasten-30-oic acid (2), 3-oxo-22α-hydroxy-20- taraxasten-30-oic acid (3), and 3β,19β-dihydroxy-20-taraxasten-30-oic acid (4) were isolated and characterized from Cirsium setosum (Willd.) MB. Their structures were determined by the combination of 1D and 2D NMR experiments ((1)H-(1)HCOSY, HSQC, HMBC and ROESY) and mass spectrometry. Compound 2 exhibited potent selective cytotoxicity against human ovarian cancer cell line A2780 with an IC50 value of 3.9 μM.

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