Anti-HIV-1 and anti-inflammatory lupanes from the leaves, twigs, and resin of Garcinia hanburyi.

Two new lupanes, 2 alpha-acetoxy-3 beta-hydroxy-19 beta-hydrogen-lup-20(29)-en-28-oic acid (2-acetoxyalphitolic acid) ( 1) and 2 alpha-hydroxy-3 beta-acetoxy-19 beta-hydrogen-lup-20(29)-en-28-oic acid (3-acetoxyalphitolic acid) ( 2), together with the known betulinic acid ( 3), betulin ( 4), and stimasterol-3- O- beta- D-glucopyranoside ( 5), were isolated from the leaves and twigs of GARCINIA HANBURYI. Compounds 1- 3 were also isolated from the resin of this plant. The structure of 2 was confirmed by single-crystal X-ray diffraction analysis. All of the lupanes ( 1- 4) displayed anti-HIV-1 activities in the anti-HIV-1 reverse transcriptase (IC (50) values 16.3-116.9 microg/mL) and syncytium assays (EC (50) 5.6-73.6 microg/mL, SI 1.7-3.3). Moreover compounds 1- 4 exhibited anti-inflammatory activity in an ethyl phenylpropiolate (EPP)-induced ear edema model.

Cytotoxic and anti-HIV-1 caged xanthones from the resin and fruits of Garcinia hanburyi.

Three new caged xanthones, 7-methoxydesoxymorellin (1), 2-isoprenylforbesione (2) and 8,8a-epoxymorellic acid (3), together with nine known caged xanthones were isolated from the EtOAc extracts of resin and fruits of Garcinia hanburyi. The structures were determined by spectroscopic methods. Most of the isolated compounds showed significant cytotoxicities against a panel of mammalian cancer cell lines. Compound 3, together with the known compounds desoxymorellin, morellic acid, gambogic acid, hanburin, forbesione and dihydroisomorellin, exhibited anti-HIV-1 activity in the reverse transcriptase (RT) assay while the known compounds desoxygambogenin and dihydroisomorellin were found moderately active in the syncytium assay. This work represents the first report on the anti-HIV-1 activities of caged xanthones.

Anti-HIV-1 constituents from leaves and twigs of Cratoxylum arborescens.

Two new xanthones, 1,3,8-trihydroxy-2,4-dimethoxyxanthone (1) and 1,7-dihydroxy-2,8-dimethoxyxanthone (2), along with twelve known compounds 3 - 14 were isolated from leaves and twigs of Cratoxylum arborescens. Compound 1, euxanthone (4), betulinic acid (8), lup-20(29)-ene-3beta,30-diol (9), 3beta-hydroxylup-20(29)-en-30-oic acid (10) and 3,4-dihydroxybenzoic acid (11) displayed anti-HIV-1 activities in the syncytium assay using (Delta)(Tat/Rev)MC99 virus and the 1A2 cell line system (EC (50) values between 3.9 and 32.2 microg/mL with TI ranging from 1.5 to 11.7), while 1,3,7-trihydroxy-6-methoxy-4,5-diisoprenylxanthone (3), 4, and 8 - 10 inhibited HIV-1 reverse transcriptase with IC (50) values between 8.7 and 84.9 microg/mL.

Anti-HIV-1 cycloartanes from leaves and twigs of Gardenia thailandica.

Thailandiol ( 1), gardenolic acid A ( 2), quadrangularic acid E ( 3) and 3beta-hydroxy-5alpha-cycloart-24(31)-en-28-oic acid ( 4) have been isolated from the leaves and twigs of Gardenia thailandica Tirveng (order: Rubiales; family: Rubiaceae). In addition, 5-hydroxy-7,2',3',4',5',6'-hexamethoxyflavone ( 5), 5,7-dihydroxy-2',3', 4',5',6'-pentamethoxyflavone ( 6), 5-hydroxy-7,2',3',4',5'-pentamethoxyflavone ( 7) and 5,7-dihydroxy-2',3',4',5'-tetramethoxyflavone ( 8) were also isolated from the same source. The structures were elucidated by spectroscopic methods. Crude extracts and compounds 1 - 4 displayed anti-HIV-1 activities as determined by using the (Delta)(Tat/Rev)MC99 virus and 1A2 cell line system. The EC (50) values determined by the syncytium assay ranged from < 7.8 to 110 microg/mL. They also exhibited moderate to high activities in reverse transcriptase (RT) assay; the IC (50) values of compounds 1 - 4, ranged from < 22.5 to 156.8 microg/mL.

Anti-HIV-1 limonoid: first isolation from Clausena excavata.

A 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 (IC(50) value > 20 microgram/mL).

Anti-HIV-1 protostane triterpenes and digeranylbenzophenone from trunk bark and stems of Garcinia speciosa.

Three new protostanes, garciosaterpenes A ( 1), B ( 2) and C ( 3), together with a new digeranylbenzophenone, garciosaphenone A ( 4) were isolated from the ethyl acetate fractions obtained from the crude methanol extracts of the trunk bark and stems of Garcinia speciosa. The structures were elucidated by spectroscopic methods and chemical reactions. Compounds 1 and 3 showed significant inhibitory activities (IC (50) 15.5 and 12.2 microg/mL, respectively) against HIV-1 reverse transcriptase and in the syncytium assay (EC (50) 5.8 microg/mL with TI 3.4 and 37.0 microg/mL with TI 1.9, respectively). Compound 4 was active in HIV-1 RT assay (IC (50) 23.9 microg/mL), but toxic in the syncytium assay. This work represents the first report on the anti-HIV-1 activities of the protostane triterpenes.