Yinhai Ma

Butyrolactones derivatives from the fermentation products of a plant entophytic fungus Penicillium oxalicum

Two new butyrolactone derivatives, terrelactones A and B (1 and 2), together with four known butyrolactone derivatives (3–6), were isolated from the fermentation products of the fungus Penicillium oxalicum 0403. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. The anti-tobacco mosaic virus (anti-TMV) activities of 1 and 2 were evaluated. The results showed that compounds 1 and 2 exhibited high anti-TMV activity with inhibition rates of 25.5% and 27.4%, respectively. The inhibition rate is close to that of positive control (28.9%).

Catalyst-free synthesis of 3-(1-arylsulfonylalkyl)indoles via three-component reaction of indoles, carbonyls, and arenesulfinic acids

ABSTRACT A catalyst-free three-component reaction of indoles, carbonyls, and arenesulfinic acids performed at room temperature provides direct access to biologically important 3-(1-arylsulfonylalkyl)indoles. This process features mild conditions, low cost, broad substrate scope, and high yields, and mechanistically bis(indolyl)methanes were identified as the key intermediates. GRAPHICAL ABSTRACT

Isolation of Xanthones from the Fermentation Products of the Endophytic Fungus of Phomopsis amygdali

Two new xanthones, 4,5-dihydroxy-3-(2-hydroxyethyl)-1-methoxy-8-methoxycarbonylxanthone (1) and 1,8-dihydroxy-4-(2-hydroxyethyl)-3-methoxyxanthone (2), and seven known xanthones (3–9) were isolated from the fermentation products of a Phomopsis species fungus. Compounds 1, 2, and 7 were tested for their cytotoxicity against five human tumor cell lines. Compound 1 showed cytotoxicity against A549 and PC3 cells with IC50 values of 2.6 and 2.4 μM, respectively. The other compounds also showed moderate cytotoxicity for some tested cell lines with IC50 values between 5.2–9.2 μM.

Three-Component Reactions of Ketene Dithioacetals, Aldehydes, and Arenesulfinic Acids: Facile Synthesis of Allylic Sulfones

Abstract A facile and efficient synthesis of allylic sulfones via sulfuric acid–mediated three-component reactions of easily available ketene dithioacetals, aldehydes, and arenesulfinic acids is presented. The reaction features low cost and good yields. GRAPHICAL ABSTRACT

Two new phenolic constituents from Clematis connata DC.

Two new phenolic compounds, 3,4-dihydroxyphenethyl 5-hydroxy-4-oxopentanoate (1) and 3-(4-hydroxy-2,5-dimethoxyphenyl)-3-oxopropyl acetate (2), together with fifteen known compounds, 3 to 17, were isolated from the dried whole plants of Clematis connata DC. Their structures were elucidated by extensive spectral analysis, especially 2D NMR techniques. Compounds 1 to 5 were evaluated for their in vitro cytotoxicities against acute promyelocytic leukemia HL-60, hepatocellular carcinoma Hep-G2, oropharyngeal epidermoid carcinoma KB and breast cancer cells MDA-MB-231. Compounds 1 and 3 exhibited the most potential with IC50 values of 0.63 and 1.27 mu M against MDA-MB-231 and HepG2, respectively. The antibacterial activities experiment of all the isolated compounds showed that only Compounds 3 to 5 exhibited weak activities against Staphylococcus aureus, methcillin-resistant S. aureus and beta-lactamase positive S. aureus, and Compound 9 and 17 showed weak activities against S. aureus.