Arunrat SunthitikawinsakulNgampong KongkathipBoonsong KongkathipSida PhonnakhuJohn W. DalyThomas F. SpandeYuth NimitChanita NapaswatJittra KasisitChalobon YoosookKasetsart UniversityNational Institute of Diabetes and Digestive and Kidney DiseasesMahidol University2018-07-242018-07-242003-11-01Phytotherapy Research. Vol.17, No.9 (2003), 1101-11030951418X2-s2.0-10744223641https://repository.li.mahidol.ac.th/handle/20.500.14594/21023A limonoid, clausenolide-1-ethyl ether (1) and two coumarins, dentatin (2) and nor-dentatin (3), were isolated from Clausena excavata. Limonoid 1 was obtained from the crude ethanol extract of the rhizomes and the roots but had not previously been isolated from C. excavata and exhibited HIV-1 inhibitory activity. Coumarins 2 and 3, with their structures related to an anti-HIV-1 substance, (+)-calanolide A (4), were obtained from the crude chloroform extract of the rhizomes. Both induced toxicity to cells used in a syncytium assay for anti-HIV-1 activity. These compounds, 1-3, did not show any cytotoxic effect against KB and BC-1 cell lines (IC50value > 20 μg/mL). Copyright © 2003 John Wiley & Sons, Ltd.Mahidol UniversityPharmacology, Toxicology and PharmaceuticsArticleSCOPUS10.1002/ptr.1381