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A novel aristololactam alkaloid, dasymalactam A ( 1 ), together with nine known analogues ( 2-10 ), were isolated from the roots of Dasymaschalon rostratum . Their structures were elucidated by IR, NMR and MS spectrums and comparisons with data reported in the literature. All compounds demonstrated weak cytotoxicity against Hela, MCF-7, A-549, MGC-803, and COLO-205 human cancer cell lines.

The ethanolic extract from the stem bark of Goniothalamus marcanii Craib was shown in preliminary brine shrimp lethality data having good cytotoxic activity. Further bioassay guided isolation was done by means of solvent partition, chromatography and precipitation to provide four isolated compounds: a novel compound 1 with the core structure of 1-azaanthraquinone moiety referred as marcanine G; as well as compounds 2-4 with known aristolactam structures namely, piperolactam C, cepharanone B and taliscanine. These compounds were characterised by spectroscopic techniques. The assessment of cytotoxicity was established on an SRB assay using doxorubicin as a positive control. Marcanine G (1) was considered the most active compound indicating the IC 50 values of 14.87 and 15.18 μM against human lung cancer cells (A549) and human breast cancer cells (MCF7), respectively. However, 2 showed mild activity with the IC 50 values of 83.72 and 82.32 μM against A549 and MCF7 cells, respectively.

Astragalin was isolated for the first time along with (-)hinokinin, aristolactam I and aristolochic acids (I & II) from the extracts of Aristolochia indica L. using a new, efficient preparative HPLC method. A reversed-phase HPLC method of analysis was developed to analyse the isolated compounds. The crude extracts and the isolated compounds were tested for their anti-inflammatory potential. We report here for the first time the anti-inflammatory effects of (-)hinokinin and aristolactam I against IL-6 (IC50 = 20.5 ± 0.5 and 52 ± 8 μM) and TNFα (IC50 = 77.5 ± 27.5 and 116.8 ± 83.25 μM), respectively. (-)Hinokinin exerted its anti-inflammatory effects via NFκB-dependent mechanism whereas aristolactam I may be effective via a mechanism independent of NFκB.

Pressalanin A, a 2-functionalized tetrahydrofuranol, has been isolated from the leaves of Michelia compressa var. lanyuensis (Magnoliaceae), and the structure was determined on the basis of a spectroscopic analysis.

Pressafonin A (1) and pressafonin B (2), two new Michelia monoterpenic esters, have been isolated from Michelia compressa (Maxim.) Sargent var. formosana Kanehira (Magnoliaceae), and their structures are determined on the basis of spectroscopic analysis.