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Viral protein R (Vpr) is an accessory protein in Human immunodeficiency virus-1 (HIV-1) and has been suggested as an attractive target for HIV disease treatment. Investigations of the ethanolic extracts of twelve Thai herbs revealed that the extracts of the Punica granatum fruits, the Centella asiatica aerials, the Citrus hystrix fruit peels, the Caesalpinia sappan heartwoods, the Piper betel leaves, the Alpinia galangal rhizomes, the Senna tora seeds, the Zingiber cassumunar rhizomes, the Rhinacanthus nasutus leaves, and the Plumbago indica roots exhibited the anti-Vpr activity in HeLa cells harboring the TREx plasmid encoding full-length Vpr (TREx-HeLa-Vpr cells). Moreover, the investigation of the selected main constituents in Punica granatum, Centella asiatica, A. galangal, and Caesalpinia sappan indicated that punicalagin, asiaticoside, ellagic acid, madecassic acid, madecassoside, zingerone, brazilin, and asiatic acid possessed anti-Vpr activities at the 10 μM concentration. Among the tested extracts and compounds, the extracts from Centella asiatica and Citrus hystrix and the compounds, punicalagin and asiaticoside, showed the most potent anti-Vpr activities without any cytotoxicity, respectively., (© 2021 Wiley-VHCA AG, Zurich, Switzerland.)

Human pregnane-X-receptor (hPXR) is considered to be the key target for the treatment of cholestasis and liver injury. Agonists of hPXR are potential drug leads. Potent and selective inhibitors of human carboxylesterase 2 (hCES2) could be utilized to alleviate the toxicity induced by ester drugs. In this work, fifteen new tetranortriterpenoids with structure diversity, named thaigranatins F-T (1-15), including four limonoids containing a C 1 -O-C 29 bridge (1-4), four mexicanolides (5-8), three phragmalins (9-11), two limonoids belonging to the small group of trichiliton A (12-13), and two apotirucallanes (14-15), were isolated from seeds of the Thai mangrove, Xylocarpus granatum. The structures of these compounds were established by high resolution-electrospray ionization mass spectroscopy, extensive NMR spectroscopic investigations, single-crystal X-ray diffraction analyses, and the comparison of experimental electronic circular dichroism spectra. Most notably, thaigranatins L (7) and P (11) exhibited agonistic effects on hPXR at the concentration of 10.0 μM and 10.0 nM, respectively, whereas thaigranatins J (5), M (8), and T (15) showed inhibitory activities against hCES2 with IC 50 values of 6.63, 11.35, and 5.05 μM, respectively. The 8α,30α-epoxy moiety of mexicanolide and the Δ 8,14 double bond of phragmalin are pivotal for agonistic effects of these limonoids on hPXR, whereas the 6-OAc group of mexicanolide is crucial for its inhibitory activity against hCES2. Additionally, the flexible C-17-side-chain with appropriate hydroxy groups is considered to be important for the inhibitory activity of apotirucallane against hCES2., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Sixteen new lanostane triterpenoids (1-16), together with 26 known compounds (17-42), were isolated from cultures of the basidiomycete Ganoderma sp. BCC 16642. Antitubercular activities of these Ganoderma lanostanoids against Mycobacterium tuberculosis H37Ra were evaluated, and structure-activity relationships are proposed.

A revised structure of colossolactone G (1), seven new triterpene lactones, ganodermalactones A-G (2-8), and five known triterpene lactones, colossolactone I (9), schisanlactone B (10), colossolactone B (11), colossolactone E (12), and colossolactone IV (13), and ergosterol have been isolated from cultured biomass of the macrofungi Ganoderma sp. KM01. Their structures were identified by spectroscopic methods. Structures and relative configurations of 3, 7, and 8 were confirmed by X-ray crystallographic analysis. Compounds 7, 10, and 12 exhibited antimalarial activity against Plasmodium falciparum in the range 6.0-10.0 μM (IC50).

Twenty-one triterpenes consisting of a lupane derivative, two friedelanes, an oleanane derivative, and 17 ursane-type triterpenoids, together with three known triterpenes, three sterols, a fatty acid, a sesquiterpene alkaloid, and a glycerol derivative, were isolated from the stem of Siphonodon celastrineus. Their structures were characterized by various spectroscopic techniques, as well as comparison with literature data. Twenty-seven metabolites of these were evaluated for cytotoxic activity against six human cancer cell lines. The biosynthetic formation of a 1,4-dioxane bridge is also discussed., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Eight new cycloartane triterpenoids (1-8), named carinatins A-H, and the known compounds secaubryolide (9) and dikamaliartane D (10) were isolated from the leaves and twigs of Gardenia carinata. Their structures were determined on the basis of spectroscopic methods. Cytotoxic, antitopoisomerase IIα, and anti-HIV-1 activities of compounds 1-7, 9, and 10 were investigated.

Seven new lanostane-type triterpenes, hypocrellols A-G (1-7), and six new hopane-type triterpenes, 7β,15α-dihydroxy-22(29)-hopene (8), 3β,7β-dihydroxy-22(29)-hopene (9), 3β-acetoxy-15α-hydroxy-22(29)-hopene (10), 3β,7β,15α,22-tetrahydroxyhopane (11), 3β-acetoxy-7β,15α,22-trihydroxyhopane (12), and 7β,15α,22-trihydroxyhopane (13), were isolated from the scale insect pathogenic fungus Hypocrella sp. BCC 14524. The structures of the new compounds were elucidated by analyses of the NMR spectroscopic and mass spectrometry data. The structure of 1 was confirmed by X-ray crystallography.

In our screening program for natural products that increase DR5 (death-receptor 5) expression, nine new cycloartane triterpenes, combretanones A-G (1-7), combretic acid A (8), and combretic acid B (9), were isolated from a MeOH extract of Combretum quadrangulare leaves. The known oleanane triterpenes (10, 11) and six known flavonols (12-17) were also isolated. The structures of 1-9 were elucidated by spectroscopic studies. Compounds 7, 9, 12, 16, and 17 enhanced DR5 expression, and 16 showed TRAIL-resistance abrogating activity.

Two new triterpenes, 17(21)-hopene-6alpha,12beta-diol (1) and 17(21)-hopen-12beta-ol (2), the known 17(21)-hopen-6alpha-ol (zeorinin, 3), and two new biarylic dihydronaphthopyrones, aschernaphthopyrones A (4) and B (5), were isolated from the scale insect pathogenic fungus Aschersonia paraphysata BCC 11964. Hopene 1 and aschernaphthopyrone A (4) exhibited antimalarial activity with IC(50) values of 15 and 7.3 microM, respectively.

Four new 3,4-seco-cycloartanes, gardenoins A-D (1-4), together with the known compound secaubryenol (5), were isolated from the exudate of Gardenia tubifera. The structures of 1-4 were elucidated on the basis of spectroscopic analysis. The cytotoxic activity of compounds 1-4 was evaluated against five human tumor cell lines.

Five new 3,4-seco-cycloartanes, sootepins A-E (1-5), along with four known triterpenes (6-9), were isolated from the apical buds of Gardenia sootepensis. Their structures were elucidated on the basis of spectroscopic methods (1D and 2D NMR, HRESIMS, and X-ray crystallography), and the compounds were tested for in vitro cytotoxic activity against human breast (BT474), lung (CHAGO), liver (Hep-G2), gastric (KATO-3), and colon (SW-620) cancer cell lines. Generally, the compounds possessing an exomethylene gamma-lactone ring showed broad cytotoxicity for all cell lines tested.

Two new acylated triterpenoid saponins were isolated from the branches of Schima noronhae by bioassay-guided purification. Their chemical structures were established on the basis of spectroscopic analysis and chemical means as 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-galactopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl 22-O-angeloyl-A1-barrigenol (1) and 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-galactopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl 22-O-angeloylerythrodiol (2). Compounds 1 and 2 showed cell growth inhibitory activity against both HeLa and DLD1 cells at a concentration of less than 10 microM.

Chemical investigation of the aerial parts of Phyllanthus acutissima resulted in the isolation of five new dichapetalin-type triterpenoids, acutissimatriterpenes A-E ( 1- 5), and two new lignans, acutissimalignans A ( 6) and B ( 7), along with two known lignans and three known ellagic acid derivatives. The structures of 1- 7 were determined mainly on the basis of spectroscopic methods. The compounds obtained were evaluated for cytotoxic and anti-HIV-1 activities.

Two new taraxerane triterpenes, 2,3-seco-taraxer-14-ene-2,3,28-trioic acid 2,3-dimethyl ester ( 1) and 2,3-seco-taraxer-14-ene-2,3,28-trioic acid 3-methyl ester ( 2), along with two known triterpenes, hopenol B and aleuritolic acid, and five known flavonoids, putraflavone, kaempferol, sequoiaflavone, amentoflavone, and ginkgetin, were isolated from the leaves of Elateriospermum tapos. The stem extract yielded a new cleistanthane diterpene, 2,3-seco-sonderianol ( 3), three known triterpenes, lupeol, lupeol acetate, and 3-acetylaleuritolic acid, and three known diterpenes, yucalexin B-22, yucalexin P-15, and yucalexin P-17. The structures of these compounds were established on the basis of their spectroscopic data. Compound 1 was cytotoxic against NCI-H187 and BC cell lines and also showed in vitro antimycobacterial activity against Mycobacterium tuberculosis.

Three new dammarane triterpenes, bruguierins A-C (1-3), were isolated from a petroleum ether extract of the flowers of Bruguiera gymnorrhiza. Their structures were determined on the basis of physical and spectroscopic data interpretation. With stably transfected HepG2 cells, the three isolates activated antioxidant response element (ARE luciferase activation) with EC(50) values of 7.8, 9.4, and 15.7 microM, respectively. Bruguierin A (1) also inhibited phorbol ester-induced NFkappaB (nuclear factor-kappaB) luciferase activation with an IC(50) value of 1.4 microM and selectively inhibited cyclooxygenase-2 (COX-2) activity with an IC(50) value of 0.37 microM. Compounds 2 and 3 were not active in these bioassays.

A new 1,3-dihydroxy-2-methyl-5,6-dimethoxyanthraquinone (1); six known anthraquinones, nordamnacanthal (2), damnacanthal (3), rubiadin (4), rubiadin-1-methyl ether (5), lucidin-omega-methyl ether (6), and 1-hydroxy-2-hydroxymethyl-3-methoxyanthraquinone (7); a beta-sitosterol (8); together with two known triterpenoids, beta-acetylolean-12-en-28-olic acid (9), and 3beta-O-acetyl-11alpha,12alpha-epoxyolean-28,13-olide (10) were isolated from the roots and stems of Prismatomeris fragrans. Their structures were established on the basis of spectral data. This is the first isolation of compounds 2, 6, 7, 9 and 10 from Prismatomeris genus. The isolated compounds were evaluated in antiplasmodial, antituberculosis, antifungal and anticancer cell lines tests. The bioactivity assays showed that only 9 exhibited moderate antimalarial activity, 2 and 3 exhibited antifungal activity while 2, 3, 4, 7 and 9 showed antituberculosis activity. In addition, compounds 2, 3 and 7 exhibited cytotoxicity to BC cell line while 1, 1a (the methyl ether derivative of 1), 2, 3, 4, 5, and 9 exhibited cytotoxicity to NCI-H187 cell line.

Five new triterpenes, one 17,14-friedolanostane (garcihombronane F, 1), three 17,13-friedolanostanes (garcihombronanes G-I, 2-4), and one lanostane (garcihombronane J, 5), were isolated from the leaves of Garcinia hombroniana together with nine known compounds including five triterpenes, two ionone-derived glycosides, and two flavonoid glucosides. Their structures were identified by analysis of spectroscopic data and comparison of the NMR data with those previously reported.

Six new pentacyclic triterpenoid esters (1-6) together with 3alpha- and 3beta-taraxerol were isolated from the fruits of Bruguiera cylindrica. The structures of the new compounds were characterized as 3alpha-E-feruloyltaraxerol (1), 3alpha-Z-feruloyltaraxerol (2), 3beta-E-feruloyltaraxerol (3), 3beta-Z-feruloyltaraxerol (4), 3alpha-E-coumaroyltaraxerol (5), and 3alpha-Z-coumaroyltaraxerol (6), respectively. Compounds 2 and 6 exhibited weak cytotoxicity against the NCI-H187 cell line.

Three new friedelane-type triterpenes named salasones A (1), B (2), and C (3), a new norfriedelane-type triterpene, salaquinone A (4), and a new acylated eudesmane-type sesquiterpene, salasol A (5), were isolated from the 80% aqueous methanolic extract of the stems of Salacia chinensis collected in Thailand. Their stereostructures were elucidated on the basis of chemical and physicochemical evidence. In addition, six constituents, 3beta,22beta-dihydroxyolean-12-en-29-oic acid, tingenone, tingenine B, regeol A, triptocalline A, and mangiferin, were found to show an inhibitory effect on rat lens aldose reductase.

Five new oleanane-type triterpene saponins, albiziasaponins A-E (1-5), were isolated from the stems of Albizia myriophylla collected in Thailand, together with two known triterpene saponins, licorice-saponin F3 and yunganoside B(1). The structures of the new compounds were elucidated on the basis of chemical and physicochemical evidence. In addition, when sensory tests were performed on sweetness, albiziasaponin B (2), with a carbonyl group at the C-30 position, was found to show a potent sweetness intensity relative to sucrose (600 times).

Three new natural onoceranoid triterpenes, lansionic acid (1), 3beta-hydroxyonocera-8(26),14-dien-21-one (2), and 21alpha-hydroxyonocera-8(26),14-dien-3-one (3), were isolated from the fruit peel of Lansium domesticum together with two known triterpenoids (4 and 5), and their structures were elucidated from spectral data. These triterpenoids exhibited mild toxicity against brine shrimp (Artemia salina).

Three new 12beta-hydroxymultiflorane triterpenoid acids, sandorinic acids A-C (1-3), were isolated from the stem bark of Sandoricum indicum together with five known triterpenes (4-8). The structures of 1-3 were elucidated by spectral data interpretation. Compounds 1-8 were evaluated for their inhibiting activity against several tumor cell lines and for their effects on lymphocyte proliferation.