Supercritical fluid extraction assisted isolation of sesquiterpene lactones with antiproliferative effects from Centipeda minima.

Pseudoguaianolide sesquiterpene lactones minimolides A (1), B (2), C (3) and D (4) and two guaianolide sesquiterpene lactones minimolides E (5) and F (6), along with seven known ones (7-13), were isolated from the supercritical fluid extract of Centipeda minima. The structures of these compounds were elucidated by extensive spectroscopic methods (IR, UV, HRESIMS, 1D-NMR and 2D-NMR), and the complete structure and stereochemistry of 1 was further confirmed by X-ray diffraction analysis. Compounds 1, 5-8,11 and 13 displayed inhibitory activity against human nasopharyngeal cancer cells (CNE) with IC(50) values ranging from 1.

[Studies on the chemical comstituents of Pithecellobium clypearia].

Objective: To study the chemical constituents of Pithecellobium clypearia.

Methods: The compounds were isolated from Pithecellobium clypearia with column chromatography. Their structures were characterized on the basis of their physical and chemical preperties, as well as chromatographic and spectroscopic evidences.

[Studies on the chemical constituents of Adina pilulifera].

The chemical constituents of Adina pilulifera, which were traditionlly used in the area of Yao minority in Southern China, were isolated and characterized. Two compounds were obtained from the ethyl acetate fraction of ethanol extract of Adina pilulifera, and one compound was obtained from the n-butanol fraction of ethanol extract of Adina pilulifera. Their structure were characterized by spectroscopic analysis and comparison with published data to be sarracenin (1), 2-methyl-5, 7-dihydroxychromone (2) and morroniside (3).

[Study on the chemical constituents of Ardisia chinensis].

The chemical constituents of Ardisia chinensis, which traditionally used in the area of Yao minority in Southern China, were analyzed and characterized. Seven compounds were obtained from the ethyl acetate fraction of ethanol extract of Ardisia chinensis. These 7 compounds were characterized by spectroscopic analysis and comparison with published data to be salicylic acid (1), 4-hydroxy-3-methoxy-benzoic acid (2), gallic acid ethyl ester (3), 4-hydroxy-3,5-dimethoxy benzoic acid methyl ester (4), protocatechuic acid (5), gallic acid (6) and catechin (7).

[Studies on antiviral constituents in stems and leaves of Pithecellibium clypearia].

Objective: To study the antiviral constituents in the stems and leaves of Pithecellibium clypearia.

Method: The constituents of P. clypearia were systematically separated with various chromatographic techniques in combination with antiviral activity monitoring.