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Bioactivity guided separation of Walsura trichostemon stem methanolic extract led to the isolation of four new dammarane (1-4) and two new apotirucallane triterpenoids (5-6), together with one limonoid (7), 11,25-dideacetyltrichostemonate, 12β, 20S, 24R-trihydroxydammar-25-en-3-one and 12β, 20S, 25-trihydroxydammar-23-en-3-one. Compounds 1-7 showed in vitro inhibitory activity on the proliferation of A549, human lung adenocarcinoma cell line.

Phytochemical investigation of the leaves of Guarea convergens T. D. Penn. led to the isolation of new apotirucallane triterpenes 24-acetoxy-25-hydroxy-3,7-dioxoapotirucalla-14-en-21,23-olide and 7α,24,25-trihydroxy-3-oxoapotirucalla-14-en-21,23-olide, steroid ergosta-5,24(24′)-diene-3β,7α,21-triol, in addition to the known ergosta-5,24(24′)-diene-3β,4β,22S-triol. The investigation from branches yielded the tirucallane triterpenes melianone and melianodiol. This is the first chemical study of this species, whose identified molecules contribute to knowledge of the biodiversity of the Amazonian forestan for chemosystematics of the Rutales order.

Ten new triterpenoid compounds with structure diversity of the C-17 side-chain, including nine tirucallanes, named xylocarpols A&ndash, E (1&ndash, 5) and agallochols A&ndash, D (6&ndash, 9), and an apotirucallane, named 25-dehydroxy protoxylogranatin B (10), were isolated from the mangrove plants Xylocarpus granatum, Xylocarpus moluccensis, and Excoecaria agallocha. The structures of these compounds were established by HR-ESIMS and extensive one-dimensional (1D) and two-dimensional (2D) NMR investigations. The absolute configurations of 1 and 2 were unequivocally determined by single-crystal X-ray diffraction analyses, conducted with Cu K&alpha, radiation, whereas those of 4, 6&ndash, 8 were assigned by a modified Mosher&rsquo, s method and the comparison of experimental electronic circular dichroism (ECD) spectra. Most notably, 5, 6, 7, and 9 displayed potent activation effects on farnesoid&ndash, X&ndash, receptor (FXR) at the concentration of 10.0 &mu, M, 10 exhibited very significant agonistic effects on pregnane&ndash, receptor (PXR) at the concentration of 10.0 nM.

Five new apotirucallane-type terpenoids, Piscidinols H-L (1-5), were isolated from the leaves of Walsura trifoliate and their structures were fully established on the basis of detailed spectroscopi ...

Three new compounds, the degraded ring C-seco-tetranortriterpenoid nimbolicidin (1), the degraded hexanortriterpenoid nimbocin (2), and the seco-norabietane diterpene nimbocinin (3), were isolated from the root bark of Azadirachta indica A.Juss. Compound 1 is O-bearing both at C(28) and C(29), which has been hitherto unreported in tetranortriterpenoids; 2 represents the first hexanortriterpenoid with a truncated apotirucallane (or apoeuphane) skeleton; 3 is an unprecedented seco-norabietane. Spectroscopic data and chemical transformations of these compounds provided their complete structures.

Two new apotirucallane-type isomeric triterpenoids, named as dictamnin A (1) and dictamnin B (2), with six limonoids, obacunone (3), limonin (4), rutaevin (5), 7 α -obacunyl acetate (6), fraxinellone (7), fraxinellonone (8), were isolated from the root bark of Dictamnus dasycarpus Turcz. (Rutaceae). Their structures were well determined by means of IR, MS, 1D and 2D NMR techniques. Both new apotirucallane-type isomeric triterpenoids displayed good antiproliferative effects on lung cancer cells A549 and resulted in a clear increase of the percentage of cells in G1 phase and a decrease in the percentage of cells in S and G2/M phases in comparison with control cells.

Dictamins A–C, the first known examples of apotirucallane-type trinortriterpenoids, were isolated from the root bark of Dictamnus dasycarpus . Their structures and relative configurations were elucidated on the basis of extensive NMR and single-crystal X-ray diffraction analyses. Such compounds might be the key C 5 side chain intermediates for an alternative degradation process from protolimonoids (C 8 side chain) to limonoids (C 4 side chain), bridging an oxidative cleavage biogenetic pathway between these two classes of structurally diverse triterpenoids.

The isolation and structure elucidation of two new triterpenes named feroniellides A (1) and B (2) from Feroniella lucida are described. Feroniellide A has a novel dioxabicyclic [3.2.1]octane moiety, and feroniellide B is the C-3 epimer of the known triterpenoid 3. Their overall structures and relative configurations were established by combined spectral data analysis. The cytotoxicity of 1 and 2 was also evaluated against human KB and HeLa carcinoma cells.

Nine new triterpenoids, 1-9, were isolated from the cortex of Cedrela sinensis (Meliaceae), together with six known compounds, sapelin E acetate, grandifoliolenone, azadirone, bourjotinolone A, piscidinol A, and hispidol B. The structures of 1-9 were determined by the 2D NMR experiments, chemical methods, and X-ray crystallography.

The insecticidal activity of piscidinols H (I), I (IIa), J (III), K (IIb) and L (IV) is evaluated to be negligible.

A new triterpenoid (1) with apotirucallane skeleton was isolated from the ethanol extract of the roots of Atalantia buxifolia (Poir.) Oliv. The complete structural assignment of the new compound was elucidated by a combination of 1D, 2D NMR (HMQC, HMBC, COSY, and NOESY), and HR-ESI-MS analysis. Moreover, this new compound was evaluated in vitro for its cytotoxic, antimicrobial and enzymes inhibitory activities.

During studies on the structurepesticidal-activity relationship of Azadirachta indica constituents, azadiradione (1) was treated with methanolic K2CO3 to obtain 7-deacetyl derivative nimbocinol (2). Unexpectedly, 17β-hydroxynimbocinol (3), reported earlier as a natural product, was also formed. The structurepesticidal-activity relationship of triterpenoids 1–16 against Anopheles stephensi Liston is described towards understanding the active functionalities responsible for the pesticidal activity of triterpenoids having apoeuphane(apotirucallane) and gedunin skeleta. The pesticidal activities of triterpenoids 2–8 are reported for the first time.

The leaves of Luvunga sarmentosa yielded two new apotirucallane triterpenoids, 3-epi-skimmiarepin A (1) and 21,23-epoxy-7α,21-dihydroxyapotirucalla-14,24-dien-3-one (2), and a new tirucallane trite...

A new apotirucallane, trichostemonate (1), was isolated from the roots of Walsura trichostemon. The complete structural assignment of this new compound was elucidated from spectroscopic methods and the stereochemistry of 1 was confirmed by X-ray crystallographic analysis. Moreover, this new compound was evaluated for its cytotoxicity (KB and HeLa cells), and showed significant cytotoxicity against both KB and HeLa cell lines with IC50 values of 3.28 and 0.93 μg/mL, respectively.

Two new 3,4- seco-apotirucallane triterpenoids, Apowalsogynes A and B (1 and 2), were isolated from the barks of Walsura chrysogyne, and their structures were determined on the basis of the NMR and CD spectra, and by using the modified Mosher's method. In addition, the cytotoxic activities of 1 and 2 against various cancer cell lines were evaluated.

Five new apotirucallane triterpenes were isolated from the seeds of Aglaia argentea : gentinones A (1), B (2), C (3), D (4), and gentinin (5). Their structures were established using spectroscopic and chemical means.

This paper reports the chemical isolation and antibacterial properties of terpenoid components of Dysoxylum densiflorum. Three new tetracyclic triterpenoic acids, densiflorinic acids A-C (1-3), were isolated from the acetone extract of the plant's leaves. The structures of the three compounds were determined mainly by extensive analysis of 1-D and 2-D NMR spectroscopic data. On antibacterial evaluation, the highest activity was shown by compound 1 against Bacillus subtilis with an IC50 of 26.5 μM.

Piscidinol F, a new apotirucallane, has been isolated from the leaves of Walsura piscidia in addition to the other piscidinols. The side chain configuration of piscidinol B has been established from 1 H NMR data.

Two new bioactive apotirucallane triterpenes, meliavolkensins A ( 1 ) and B ( 2 ), were isolated from the root bark of Melia volkensii (Meliaceae). These two compounds have a new type of substituted tetrahydropyran ring side chain, and their structures have been elucidated by spectroscopic analyses. 1 and 2 also show cytotoxic selectivities to a hyman colon tumor cell line (H-29).

Two new bioactive apotirucallane triterpenes, meliavolkensins A ( 1 ) and B ( 2 ), were isolated from the root bark of Melia volkensii (Meliaceae). These two compounds have a new type of substituted tetrahydropyran ring side chain, and their structures have been elucidated by spectroscopic analyses. 1 and 2 also show cytotoxic selectivities to a hyman colon tumor cell line (H-29).

Nine new triterpenoids, 1-9, were isolated from the cortex of Cedrela sinensis (Meliaceae), together with six known compounds, sapelin E acetate, grandifoliolenone, azadirone, bourjotinolone A, piscidinol A, and hispidol B. The structures of 1-9 were determined by the 2D NMR experiments, chemical methods, and X-ray crystallography.

A chemical investigation of the bark of Simarouba amara, collected in Barbados, resulted in the isolation of six new triterpenes (3-8), in addition to two known compounds, 3-oxatirucalla-7, 24-dien-23-ol (1) and niloticin (2). Compound 3 is a tirucallane triterpene, while compounds 4-7 are apotirucallane derivatives containing an epsilon-lactone in ring A. Compounds 6 and 7 were obtained as a mixture that could not be separated, while compound 8 is an octanorapotirucallane derivative that lacks the C(8) side chain. The structures of all compounds were determined by interpretation of physical data.

Detailed chemical studies on the cytotoxic fraction from the leaves of Dysoxylum cumingianum have resulted in the isolation of two new triterpene glucosides, cumingianosides P (18) and Q (19), with an apotirucallane-type skeleton. The structures of 18 and 19 were determined by spectral examinations, and by conversion of cumingianosides C (3) and A (1) into 18 and 19, respectively. The cytotoxicities of cumingianosides P and Q against over 50 human cancer cell lines were evaluated. Cumingianoside P exhibited significant (EC504 microM) cytotoxicity against 37 human cancer cell lines. Among them, the UO-31 (renal cancer) cell line was the most sensitive to this compound (EC50 0.267 microM). In contrast, cumingianoside Q showed selective cytotoxicity against NCI-H522 (non-small cell lung cancer) cells with an EC50 value of 1.67 microM, and exhibited no cytotoxicity (EC5010 microM) against most of the remaining cancer cell lines.

A new apotirucallane-type triterpenoid with an unusual 22,23-epoxy group in the side chain, 22,23-epoxy-apotirucalla-14-ene-3α,7α,24α,25-tetraol (1), was isolated from the leaves and twigs of Orophea yunnanensis. The structure of 1 was established on the basis of HRESIMS, 1D, and 2D NMR spectroscopic methods. This is the first phytochemical study of Orophea yunnanensis, and the biogenetic origin of 1 was postulated. Compound 1 exhibited weak cytotoxicity in vitro against the growth of CNE1 nasopharyngeal carcinoma cell line with an IC50 value of 9.7 μg/mL.

Six new tirucallane protolimonoids, toonapubesins A-F (1-6), one new rearranged tirucallane protolimonoid, toonapubesin G (7), and two new 21,22,23-trinorapotirucallane limonoids, toonapubesic acids A (8) and B (9), possessing an unprecedented carbon skeleton, along with five known tirucallane protolimonoids (10-14) and one known apotirucallane limonoid (15), were isolated from the stem bark of Toona ciliata var. pubescens. Their structures and relative configurations were determined by detailed spectroscopic analysis and by chemical methods. The proposed structures of 8 and 11 were confirmed by X-ray diffraction analysis of their respective derivatives (8a and 11a). The absolute configuration of 8 was determined by a novel solid-state TDDFT ECD approach on its derivative 8a while the absolute configuration of 10 was determined by the modified Mosher's method. In addition, the structures of dyvariabilin H (10c) proposed by Sticher et al. and cneorin-NP(36) (11b) by Mondon et al. were corrected as 10 and 11, respectively. Toonapubesin G (7) showed promising inhibitory activity against CDC25B with an IC(50) value of 2.1 μM, while compound 8a showed significant cell protecting activity against H(2)O(2)-induced SH-SY5Y cell damage with 11.5% increase in cell viability.

Epoxidation of 3β - Acetoxy - 7α - hydroxy - Δ14 - apotirucallane, prepared from Δ7-tirucallone, afforded the corresponding 14α,15α epoxide. The α-configuration of the epoxide function has been established by single-crystal X-ray analysis, representing the first such study of a tirucallol derivative with an intact side-chain. Epoxidation of Apotirucalla - 3,7 - dione gave the corresponding 14α,15α - epoxide as well. Eight new tirucallol derivatives were described.

The structure of a new apotirucallane-type triterpene, 21-O-acetyl toosendantriol, isolated from the fruit of Melia toosendan was determined by X-ray analysis. Based on comparison of the 13C chemical shifts, the steric structures of the side chains of two epimeric 21-acetates derived from a tirucallane-type terpene, melianone were also clarified.

Two new apotirucallane triterpenoids, namely chisiamols G (1) and H (2), featuring a 21,23-lactone, together with five known triterpenoids, were isolated from the twigs of Chisocheton paniculatus. The structures of the new compounds were elucidated on the basis of spectroscopic and chemical methods.

Isonimolicinolide (1) and nimolicinoic acid (3), two new triterpenoids have been isolated from the neutral fraction of the fresh, undried, unruptured, ripe fruits of Azadirachta indica(neem) and their structures elucidated through chemical and spectral studies. The mother fraction of the two triterpenoids showed insect growth regulating properties against the pulse beetle (Callasobruchus analis). Isonimolicinolide (1) is the first example of a tetranortriterpenoid with an acetoxy function at C-17, and nimolicinoic acid (3) is the first instance of a hexanortriterpenoid with an apoeuphane (apotirucallane) skeleton as well as the first hexanortriterpenoidal acid, isolated from any source.