Five new lindenane disesquiterpenoids, chlorajaponilides A-E (1-5), together with 11 known analogues were isolated from whole plants of Chloranthus japonicus. The structure and absolute configuration of 1 was confirmed by X-ray crystallography. Compounds 1 and 2 represent the first examples of lindenane disesquiterpenoids with a C-5 hydroxy group and a C-4-C-15 double bond. Compounds 8, 9, 11, and 12 showed anti-HIV-1 replication activities in both wild-type HIV-1 and two NNRTIs-resistant strains. Shizukaol B (8) exhibited the best activity against HIV(wt), HIV(RT-K103N), and HIV(RT-K103N) with EC₅₀ values of 0.22, 0.47, and 0.50 μM, respectively. Compounds 8, 9, 11, and 12 had significant cytotoxicities against C8166 cells with CC₅₀ values of 0.020, 0.089, 0.047, and 0.022, respectively, and exhibited inhibitory activities against HIV-1 with EC₅₀ values of 0.0014, 0.016, 0.0043, and 0.0033 μM, respectively.

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Investigation on the extracts of Hydnocarpus anthelminthica seeds led to the isolation of three new compounds, anthelminthicins A-C (1-3, resp.), and two known ones, namely chaulmoogric acid (4) and ethyl chaulmoograte (5). Their structures were determined mainly by using spectroscopic techniques. The absolute configuration at the cyclopentenyl moiety of compound 2 was rationalized by quantum calculations. Base hydrolysis, followed by optical-rotation comparison, allowed assignment of the configuration of chaulmoogric-acid moiety of compounds 3 and 5. Biological assays revealed that compounds 1-5 significantly inhibit Mycobacterium tuberculosis (MTB) growth with MIC values of 5.54, 16.70, 4.38, 9.82, and 16.80 microM, respectively. Compound 3 was found to inhibit the pathway between chorismate and para-aminobenzoic acid (pAba) with a MIC value of 11.3 microM, representing a new example of pAba inhibitor isolated from a natural source. All compounds were not toxic to Candida albicans SC5314 at a concentration up to 100 microM.

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Three new glycoalkaloids, N-formyl-asimilobine-2-O-β-D-glucoside (1), (-)-1-O-β-D-glucoside-8-oxotetrahydropalmatine (2), and 1-N-monomethylcarbamate-argentinine-3-O-β-D-glucoside (3) were isolated from tubers of Stephania succifera. The structures were established based on spectroscopic analysis, and the antimicrobial activities of the three glycoalkaloids are reported.

Phytochemical investigation of whole plants of Euphorbia pilosa led to the isolation and identification of two new daphnane-diterpenoid glucosides, euphopilosides A and B (1 and 2, resp.), and a new ent-abietane, euphopilolide (3), together with eight known compounds. Compounds 1 and 2 are the first daphnane-type diterpenoid glycosides. Their structures were elucidated by a combination of 1D- and 2D-NMR, and MS analyses, and acid hydrolysis. Compounds 1-9 were evaluated for their in vitro cytotoxicities against five human tumor cell lines, HL-60, SMMC-7721, A-549, MCF-7, and SW-480. Compound 7 showed moderate inhibitory activity against all five cell lines.