Airlanggins A-B,two new isoprenylated benzofuran-3-ones from the stem bark of Calophyllum soulattri

Two new isoprenylated benzofuran 3-ones, airlanggin A (1) and B (2) along with two known xanthones, ananixanthone (3) and trapezifolixanthone (4) were isolated from the stem bark of Calophyllum soulattri. Structures of all the compounds were elucidated using extensive spectroscopic methods, including UV, IR, HRESIMS, 1D and 2D NMR. Compounds 1–4 were evaluated for their cytotoxicity against P-388 cells, showing that compound 3 was the most active with IC₅₀ 0.68 μg/mL and compound 1 showed moderate activity with IC₅₀ 5.80 μg/mL.     

Phylattrin, a new cytotoxic xanthone from Calophyllum soulattri

Our continuing studies on secondary metabolites from the stem bark of Calophyllum soulattri has led to the isolation of another new diprenylated xanthone, phylattrin (1), in addition to five other xanthones and two common sterols. The xanthones are soulattrin (2), caloxanthone C (3), macluraxanthone (4), brasixanthone B (5) and trapezifolixanthone (6) while the sterols are stigmasterol (7) and β-sitosterol (8). The structures of these compounds were determined on the basis of spectroscopic analyses such as 1D and 2D-NMR, HRESIMS, IR and UV. Compounds 1-7 exhibited moderate cytotoxic activities against SNU-1, HeLa, Hep G2, NCI-H23, K562, Raji, LS174T, IMR-32 and SK-MEL-28 cells.     

A new coumarin from stem bark of Mesua hexapetala

A new alkylated coumarin derivative, hexapetarin (1) along with three other xanthones, trapezifolixanthone (2), cudraxanthone G (3) and 1,3,7-trihydroxy-2,4-di (3-methyl-2-butenyl)xanthone (4), and four common triterpenoids, friedelin (5), stigmasterol (6), beta-sitosterol (7) and gamma-sitosterol (8) were isolated from the stem bark of Mesua hexapetala (Clusiaceae), a plant, native to Malaysia. The structures of these compounds were elucidated and determined using spectroscopic techniques such as NMR and MS. Anti-inflammatory activity assay indicated hexapetarin (1) to possess moderate anti-inflammatory activity, while 1,3,7-trihydroxy-2,4-di (3-methyl-2-butenyl)xanthone (4) gave very good activity.     

A new chromanone acid from the stem bark of Calophyllum teysmannii

A new chromanone acid, namely caloteysmannic acid (1), along with three known compounds, calolongic acid (2), isocalolongic acid (3) and stigmasterol (4) were isolated from the stem bark of Calophyllum teysmannii. All these compounds were evaluated for their cytotoxic and antioxidant activities in the MTT and DPPH assays, respectively. The structure of compound 1 was determined by means of spectroscopic methods including 1D and 2D NMR experiments as well as HR-EIMS spectrometry. The stereochemical assignment of compound 1 was done based on the NMR results and X-ray crystallographic analysis. The preliminary assay results revealed that all the test compounds displayed potent inhibitory activity against HeLa cancer cell line, in particular with compound 1 which exhibited the highest cytotoxic activity comparable to the positive control used, cisplatin. However, no significant antioxidant activity was observed for all the test compounds in the DPPH radical scavenging capacity assay.     

Mucigerin, a new coumarin from Calophyllum mucigerum (Guttiferae)

Our recent studies on the stem bark of Calophyllum mucigerum (Guttiferae) have yielded a new coumarin mucigerin, a prenylated xanthone cudraxanthone C and the common steroidal triterpenes friedelin and stigmasterol. Structural elucidations of these compounds were achieved using 1H NMR, 13C NMR, DEPT, COSY, HETCOR and HMBC experiments while MS gave the molecular masses. Cytotoxic assays using CEM-SS cell line (T-lymphoblastic leukemia) on the crude extracts of the stem bark indicated some activity. The crude extracts were also found to be moderately toxic against the larvae of Aedes aegypti. This article reports the isolation and identification of mucigerin as well as bioassay data.     

A novel cyclodione coumarin from the stem bark of Mesua beccariana

Our ongoing investigations on the stem bark of Mesua beccariana afforded a novel cyclodione coumarin, beccamarin, together with two known xanthones, mesuarianone, mesuasinone, two anthraquinones, 4-methoxy-1,3,5-trihydroxy-anthraquinone and 2,5-dihydroxy-1,3,4-trimethoxyanthraquinone and one coumarin, mammea A/AB. The structures were elucidated by 1D and 2D NMR and MS techniques.     

Isofraxisecoside,a new coumarin-secoiridoid from the stem bark of Fraxinus xanthoxyloides

A new coumarin-secoiridoid diglucoside, named Isofraxisecoside, was isolated from the stem bark of Fraxinus xanthoxyloides (G. Don) Wall. ex A. DC. along with nine known compounds. The structure of new compound has been determined on the basis of ¹H, ¹³C, 2D NMR and HRMS methods.     

Seseliflorin, a new coumarin from Seseli sessiliflorum

Conclusions From the roots ofSeseli sessiliflorum Schrenk. we have isolated a new dihydrofurocoumarin C₁₈H₁₈O₅S for which the structure 5-[1-methyl-1-(trans-3-methylthioacryloyloxy)ethyl]-4,5-dihydrofuro-2,3:7,6-coumarin is proposed.All-Union Scientific-Research Institute of Medicinal Plants. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 522–524, September–October, 1970.     

Seseliflorin,a new coumarin from Seseli sessiliflorum

Chemistry of Natural Compounds - From the roots ofSeseli sessiliflorum Schrenk. we have isolated a new dihydrofurocoumarin C18H18O5S for which the structure...     

A new benzophenone from the stem bark of Garcinia benthami

From the stem bark of Garcinia benthami a new benzophenone, named Salimbenzophenone, was isolated. The structure was determined by means of spectroscopic analysis.     

A new diterpenoid from the stem bark of Populus davidiana

A new diterpenoid, named populusol A （1）, was isolated from the methanolic extraction of the stem bark of Populus davidiana. The structure was elucidated on the basis of extensive 1D and 2D NMR as well as HRFAB-MS spectroscopic analysis.     

Saradaferin, a new sesquiterpenoid coumarin from Ferula assafoetida

Phytochemical investigation of the gum resin of Ferula assafoetida resulted in the isolation and characterization of a new sesquiterpenoid coumarin, Saradaferin (1) named as [Decahydro-(3-alpha-hydroxy-4,4,10-trimethyl-8-methylene-9-naphthenyl)-alpha-hydroxymethyl] ether of umbelliferone.     

Four new isoflavonoids from the stem bark of Erythrina variegata

Bioassay-directed fractionation of the stem bark extract of Erythrina variegata L. has resulted in the isolation of three new isoflavones: 5,4'-dihydroxy-8-(3,3-dimethylallyl)-2'-methoxyisopropylfurano[4,5:6,7]isoflavone (1), 5,7,4'-trihydroxy-6-(3,3-dimethylallyloxiranylmethyl)isoflavone (2), 5,4'-dihydroxy-8-(3,3-dimethylallyl)-2'-hydroxymethyl-2'-methylpyrano[5,6:6,7]isoflavone (3) and a new isoflavanone, 5,4'-dihydroxy-2'-methoxy-8-(3,3-dimethylallyl)-2',2'-dimethylpyrano[5,6:6,7]isoflavanone (4) together with seven known compounds, euchrenone b10 (5), isoerysenegalensein E (6), wighteone (7), laburnetin (8), lupiwighteone (9), erythrodiol (10), and oleanolic acid (11). The structures were determined on the basis of spectroscopic analyses and chemical evidence. The effect of these compounds on the proliferation of rat osteogenic sarcoma (UMR106) is also reported.     

Shamiminol: a new aromatic glycoside from the stem bark of Bombax ceiba

A new aromatic glycoside, shamiminol was isolated from the stem bark of Bombax ceiba along with the known constituents stigmasta-3,5-diene, lupenone, (+/-)-lyoniresinol 2a-O-beta-D-glucopyranoside and opuntiol, obtained for the first time from this plant. The structure of shamiminol was elucidated on the basis of extensive 1D- and 2D-NMR spectroscopic and mass spectrometric studies as 3,4,5-trimethoxyphenol 1-O-beta-D-xylopyranosyl-(1 --> 2)-beta-D-glucopyranoside (1).     

Marcanine G,a new cytotoxic 1-azaanthraquinone from the stem bark of Goniothalamus marcanii Craib

The ethanolic extract from the stem bark of Goniothalamus marcanii Craib was shown in preliminary brine shrimp lethality data having good cytotoxic activity. Further bioassay guided isolation was done by means of solvent partition, chromatography and precipitation to provide four isolated compounds: a novel compound 1 with the core structure of 1-azaanthraquinone moiety referred as marcanine G; as well as compounds 2–4 with known aristolactam structures namely, piperolactam C, cepharanone B and taliscanine. These compounds were characterised by spectroscopic techniques. The assessment of cytotoxicity was established on an SRB assay using doxorubicin as a positive control. Marcanine G (1) was considered the most active compound indicating the IC₅₀ values of 14.87 and 15.18 μM against human lung cancer cells (A549) and human breast cancer cells (MCF7), respectively. However, 2 showed mild activity with the IC₅₀ values of 83.72 and 82.32 μM against A549 and MCF7 cells, respectively.     

Inophyllin A, a new pyranoxanthone from Calophyllum inophyllum (Guttiferae)

In the authors' continuing search for new natural products, their recent studies on the roots of Calophyllum inophyllum (Guttiferae) have yielded a new prenylated pyranoxanthone, Inophyllin A together with the common triterpenes friedelin and stigmasterol. Structural elucidations of these compounds were achieved through (1)H, (13)C, DEPT, COSY, HSQC and HMBC experiments. The molecular mass was determined using MS techniques. The authors report here the isolation of and structural elucidation for Inophyllin A as well as its toxicity test result. The discovery of this new natural product from the unexploited Malaysian forest will certainly contribute to the search for potential natural larvicides.     

Two new xanthones isolated from the stem bark of Garcinia lancilimba

Two new xanthones, 1,5,6-trihydroxy-6',6'-dimethyl-2H-pyrano(2',3':3,4)-2-(3-methylbut-2-enyl)xanthone (1) and 1,6,7-trihydroxy-6',6'-dimethyl-2H-pyrano(2',3':3,2)-4-(3-methylbut-2-enyl)xanthone (2), have been isolated from the stem bark of Garcinia lancilimba (Guttiferae), together with six known xanthones. Their structures were identified on the basis of extensive spectral evidence including detailed 2D NMR and HR-MS data. Two new compounds showed moderate inhibitory effect on human breast cancer MDA-MB-435S cell line.     

A new salicin derivative from the stem bark of Populus davidiana

Phytochemical study on the BuOH-soluble fraction of the stem bark of Populus davidiana resulted in the isolation of a new salicin derivative(1),named davidianoside.The structure was elucidated on the basis of extensive physicochemical and spectroscopic analyses.     

Coumarin-pi,a new antioxidant coumarin derivative from Paxillus involutus

Abstract

Chemical investigation of Paxillus involutus lead to the isolation of a new coumarin derivative coumarin-pi (1), and three known compounds (2-4). The structure of the new compound was elucidated by interpretation of 1D and 2D NMR data. Compound 1 possesses a rare benzofuranylcoumarin skeleton. The isolated compounds were evaluated for antioxidant activities and coumarin-pi (1) exhibited significant activity with IC₅₀ value of 16.3?μg/mL.