Chemical constituents of Viscum coloratum (Kom.) Nakai and their cytotoxic activities.

A new diarylheptanoid, (1 R,2S,3S,5S)-2,3-dihydroxy-3',3''-dimethoxy-4'-de-O-methylcentrolobine (1) and a new bisabolane-type sesquiterpenoid, (1 R,7S)-1,12,13-trihydroxybisabola-3,10-diene (2), together with nineteen known compounds (3-21) were isolated from the EtOH extract of the stems and branches of Viscum coloratum (Kom.) Nakai. Their structures were elucidated by extensive analysis of 1 D and 2 D NMR spectra and from the HRESIMS. All the compounds were evaluated for their cytotoxic activity against eight human tumor cell lines.

Proline-containing cyclopeptides from the marine sponge Phakellia fusca.

Four new cyclopeptides, phakellistatins 15-18 (2-5), together with five known cyclopeptides, phakellistatin 13 (1), hymenistatin 1, and hymenamides G, H, and J, were isolated from the South China Sea sponge Phakellia fusca. Their structures were elucidated by HR-ESIMS, NMR, and MALDI-TOF/TOF sequence analysis. The absolute configurations of the amino acid residues of 2-5 were assigned to be l by enantioselective HPLC analysis.

Triterpenoid saponins from the pulp of Sapindus mukorossi and their antifungal activities.

Under the guidance of anti-fungal bioassay, four previously undescribed oleanane-type and one lupane-type triterpenoid saponins, along with twelve known analogues, were isolated from the extract of Sapindus mukorossi pulps. Their structures were determined on the basis of spectroscopic analysis and chemical methods. In vitro biotests, oleanolic acid 3-O-ß-D-xylopyranosyl-(1 â†’ 3)-α-L-rhamnopyranosyl-(1 â†’ 2)-α-L-arabinopyranoside showed inhibitory activity against Trichophyton rubrum with MIC80 value of 8 µg/mL, while oleanolic acid 3-O-α-L-arabinopyranosyl-(1 â†’ 3)-α-L-rhamnopyranosyl-(1 â†’ 2)-α-L-arabinopyranoside exhibited inhibitory activity against both Trichophyton rubrum and Candida albicans with MIC80 values of 8 µg/mL.

Polyphenolic compounds from Malus hupehensis and their free radical scavenging effects.

One new 4-chromanone glycoside, 5-O-ß-d-glucopyranoside-4-chromanone (1), together with 21 known polyphenols, was isolated from the leaves of Malus hupehensis. Their structures were elucidated on the basis of extensive spectroscopic methods including NMR (1D and 2D), mass (ESIMS and HRESIMS), IR, and by comparison with the data reported in the literature. Some of the isolated compounds were screened for antioxidant activity. Compounds 18 and 14 exhibited significant antioxidant activities with SC50 values 2.73 and 2.91 µg/mL, respectively, while 17, 19, 11, 7, 20, 22, 12 and 13 exhibited moderate activities with SC50 values ranging from 5.24-11.86 µg/mL. The HPLC fingerprint profiles of the leaves and fruits extracts were also analysed, which showed that the constituents were almost the same in both the extracts except for the content of phlorizin which was present in higher amount in the leaves.