guineensine and pellitorine

The insecticidal activity of Piper nigrum fruit-derived piperidine alkaloid (piperine) and N-isobutylamide alkaloids (pellitorine, guineensine, pipercide and retrofractamide A) against female adults of Culex pipiens pallens and Aedes aegypti was examined. On the basis of 24-h LD(50) values, the compound most toxic to female C. pipiens pallens was pellitorine (0.4 µg/♀) followed by guineensine (1.9 µg/♀), retrofractamide A (2.4 µg/♀) and pipercide (3.2 µg/♀). LD(50) value of chlorpyrifos was 0.03 µg/♀. Against female A. aegypti, the insecticidal activity was more pronounced in pellitorine (0.17 µg/♀) than in retrofractamide A (1.5 µg/♀), guineensine (1.7 µg/♀), and pipercide (2.0 µg/♀). LD(50) value of chlorpyrifos was 0.0014 µg/♀.

Topics: Aedes; Alkaloids; Alkenes; Amides; Animals; Benzodioxoles; Culex; Fatty Acids, Unsaturated; Female; Heterocyclic Compounds, 2-Ring; Insecticides; Male; Piper nigrum; Piperidines; Polyunsaturated Alkamides

Bioassay-guided fractionation and purification of the aerial parts of Piper submultinerve led to the isolation of a new conjugated amide-dimer, submultinamide A (1), along with 11 known compounds. The structures were determined on the basis of spectroscopic methods. Among the tested compounds, pellitorine (2), guineensine (4), N-benzylcinnamide (6) and aristolactam BII (8) showed significant activities in the anti-syncytium assay using (ΔTat/Rev)MC99 virus and 1A2 cell line system, whereas 2 was most active (EC₅₀ 35.1 µM and selectivity index 4.7). In the HIV-1 reverse transcriptase assay, only 4 was active with IC₅₀ 50.8 µM.

Topics: Alkenes; Amides; Anti-HIV Agents; Cell Line; Dimerization; Drug Evaluation, Preclinical; Fatty Acids, Unsaturated; Heterocyclic Compounds, 2-Ring; HIV Reverse Transcriptase; Humans; Inhibitory Concentration 50; Lactams; Molecular Structure; Piper; Plant Components, Aerial; Plant Extracts; Polyunsaturated Alkamides