Tran Duc Quan

A new hydrochalcone from Miliusa sinensis

A new dihydrochalcone 4′,6′-dihydroxy-2′,3′,4-trimethoxydihydrochalcone (1) along with nine known compounds, pashanone (2), dihydropashanone (3), pinostrobin (4), 5-hydroxy-7,4′-dimethoxyflavanone (5), 5-hydroxy-6,7-dimethoxyflavanone (6), 5-hydroxy-7,8-dimethoxyflavanone (7), 24-methylencycloartane-3β,21-diol (8), liriodenine (9) and 3,5-dihydroxy-7,3’,4’-trimethoxyflavone (10), were isolated from the extracts, exhibiting cytotoxic activity (n-hexane and ethyl acetate extracts) of Miliusa sinensis. The structure of (1) was elucidated by the analysis of spectral data (IR, HR-MS, EI-MS, 1D and 2D NMR).

Cytotoxic and antimicrobial aporphine alkaloids from Fissistigma poilanei (Annonaceae) collected in Vietnam.

Two new aporphine alkaloids: 8-hydroxy-9-methoxy-1,2-methylenedioxyaporphine (1) and 8-hydroxy-3,9-dimethoxy-1,2-methylenedioxyaporphine (2) were isolated from the ethyl acetate extract of Fissistigma poilanei along with five known compounds: oxocrebanine (3), kuafumine (4), (2R,3R)-3′,4′,5,7-tetrahydroxydihydroflavonol-3-O-α-L-rhamnopyranoside (5), (+)-catechin 3-O-α-L-rhamnopyranoside (6) and quercetine 3,7-dimethoxy-3′-O-α-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyranoside (7). These two new aporphine alkaloids exhibited a moderate cytotoxic activity against four human cancer cell lines (KB, Hep-G2, MCF-7, LU) as well as antimicrobial activity against Lactobacillus fermentum, Enterococcus faecium, Staphylococcus aureus and Bacillus subtillis.

Study on Chemical Constituents of the Vietnamese Medicinal Plant Fissistigma petelotii

A new bisabolene derivative (1S*, 2R*, 4R*, 7R*, 10R*)-1,7,10,11-tetrahydroxy-1,7,11-trimethyl- 4,10(H)-2-O-cinnamoyl-bisabol-8(9)-ene (1), together with cinnamic acid (2), methyl cinnamate (3), sodium cinnamate (4) and methyl elaidate (5) have been isolated from the leaves and barks of Fissistigma petelotii. Sodium cinnamate (4) was isolated for the first time from the nature. The structures of these compounds were elucidated by analysis of their IR, MS, 1D and 2D NMR spectra. Graphical Abstract Study on Chemical Constituents of the Vietnamese Medicinal Plant Fissistigma petelotii

INVESTIGATING THE ANTI-INFLAMMATORY ACTIVITY OF AN ETHANOLIC EXTRACT FROM ARTOCARPUS TONKINENSIS LEAVES USING A COLLAGEN ANTIBODY-INDUCED ARTHRITIC MOUSE MODEL

This study was contrived for evaluating the in vitro and in vivo anti-inflammatory effects of an aqueous ethanolic leaf extract of the Vietnamese Artocarpustonkinensis A. Chev. exGagnep. usinglipopolysaccharide-stimulated RAW 264.7 macrophages and a collagen antibody-induced arthritic mouse model as well. The obtained results here demonstrate that the 70 % ethanolic leaf extract of A. tonkinensis(AT2), traditionally used in Vietnamese folk medicine for treating arthritic symptoms, has beneficial effects on pro-inflammatory cytokine inhibition and in an experimental arthritic mouse model.LPS-stimulated RAW 264.7 macrophages treated with AT2 showed a significant decrease in the production of IL-6 and TNF at concentrations of 12.5, 25 and 50 μg/mL (P < 0.05), indicating its potential anti-inflammatory properties. The treatment of CAIA mice with AT2 also led to diminish the incidence of arthritis at doses of 200 and 300 mg/kg body weight.

Chemical constituents from the leaves of Pinus dalatensis Ferré

Abstract A phytochemical study of n-hexane and ethyl acetate extracts of Pinus dalatensis Ferré leaves led to the isolation of 11 compounds, including one caryolane sesquiterpenoid (1), five labdane diterpenoids (2, 3, 4, 5, 6), one serratane triterpenoid (7), one diacylated flavonoid glucoside (8), one stilbenoid (9) and two sterols (10, 11). The structural characterisation of the isolated compounds was elucidated by spectroscopic data and comparison with the literature report on the chemical constituents from Pinus dalatensis Ferré. Futhermore, three compounds 1, 4 and 6 were obtained for the first time from the genus Pinus. Besides, compounds (2, 3, 5, 8, 9) were also subjected to cytotoxicity effect on SK-LU-1, MCF-7 and Hep-G2 cell lines, but only compound 9 expressed activities with IC50 values of 141.22, 127.81 and 166.84 μM, respectively.

Anti-proliferative diterpenes from Dacrycarpus imbricatus

Abstract A new diterpene, cassipouryl hexadecanoate (2), in addition to the cassipourol (1) and four terpenes (3–6) were isolated from the twigs and leaves of Dacrycarpus imbricatus (Blume) de Laub. The structures of the two monocyclic diterpenes (1, 2), were elucidated on the basic of 1D and 2D NMR spectroscopic data and compared with the literature. These two monocyclic diterpenes (1, 2) were tested for their anti-proliferative activity on acute myeloid leukemia (OCI-AML) cells. The results showed that 1 had significantly anti-proliferative activity whereas 2 was weakly active.

Chemical constituents and their biological activity of Pinus dalatensis. Part 1. Terpenoids from the leaves

Seven terpenoids were isolated from the dried leaves of Pinus dalatensis Ferre, including one caryolane sesquiterpenoid ( 1 ), five labdane diterpenoids ( 2 , 3 , 4 , 5 , 6 ) and one serratane triterpenoid (7). The structures of the isolated compounds were determined on the basic of spectroscopic methods (ESI-MS, NMR) and comparison with reported data. Among these compounds, the mixture of compounds 2 and 3 showed inhibitory effects on the growth of acute myeloid leukemia (OCI-AML) cells. This is the first report on the chemical compositions of Pinus dalatensis in Vietnam. Keywords. Pinus dalatensis , serratane triterpenoid, caryolane sesquiterpenoid, labdane diterpenoid, acute myeloid leukemia, antiproliferative effect.

Chemical constituents of Chirita drakei Burtt collected in Ha Long Bay, Quang Ninh province, Viet Nam. Part 2. Compounds isolated from the n-butanol extract

Four phenol glycosides together with cannabiside B were isolated from the n-butanol extract of the aerial part of Chirita drakei Burtt collected in islands, on mountain slopes of Ha Long bay, Quang Ninh province. Their structures have been elucidated by mass, NMR spectroscopy and comparison with published data. Compounds 4 and 5 were obtained for the first time from the genera Chirita.

Chemical constituents of Oldenlandia pinifolia and their antiproliferative activities

Abstract This study describes the chemical constituents of Oldenlandia pinifolia (Wall. Ex G. Don) Kuntze (synonym Hedyotis pinifolia Wall. Ex G. Don) and discusses their anti-proliferative activities. Thirteen compounds were isolated from the n-hexane, ethyl acetate and n-butanol extracts of whole plants O. pinifolia by chromatography method. Their structures were elucidated using MS and NMR analysis and compared with reported data. They are three anthraquinones, a carotenoid, two triterpenes, four iridoid glycosides and three flavonoid glycosides. Among them, 2-methyl-1,4,6-trihydroxy-anthraquinone is a new one, and three compounds were found for the first time in this genus. MTT assay resulted that the n-butanol extract and four isolated compounds inhibited the proliferation of chronic myelogenous leukaemia cells. The results from Hoechst 33343 staining and caspase 3-inducing exhibited that those four tested compounds induced apoptosis and activated caspase 3 (p < 0.05). One of them, isorhamnetin-3-O-β-rutinoside showed the most activity with IC50 value of 394.68 ± 25.12 μM.

Diterpenoids from the wood of Podocarpus neriifolitus

Using combined chromatographic methods, three known diterpenoids, inumakiol D ( 1 ), totarol ( 2 ) and totarol-19-carboxylic acid ( 3 ) along with β -sitosterol and β -sitosterol glucoside were isolated from the ethyl acetate extract of the wood of Podocarpus neriifolius collected in Lam Dong province, Vietnam. Their structures were determined by MS, 1D-, 2D-NMR data analysis and comparison with published references. This is the first report of compounds 1-3 from this plant. Keywords. Podocarpus neriifolius, diterpenoid, inumakiol D, totarol, totarol-19-carboxylic.