Cytotoxic and antimalarial constituents from the roots of Eurycoma longifolia

Sixty-five compounds were isolated from the roots of Eurycoma longifolia and characterized by comprehensive analyses of their 1D and 2D NMR, and mass spectral data. Among these isolates, four quassinoid diterpenoids were reported from natural sources for the first time, namely eurycomalide A (1), eurycomalide B (2), 13beta, 21-dihydroxyeurycomanol (3), and 5alpha, 14beta, 15beta-trihydroxyklaineanone (4). Screening of cytotoxicity, anti-HIV and antimalarial activity of these isolated compounds was also furnished by in vitro assays. Compounds 12, 13, 17, 18, 36, 38, 59, and 62 demonstrated strong cytotoxicity toward human lung cancer (A-549) cell lines, however, 12, 13, 17, 38, 57, 58, and 59 exhibited strong cytoxicity toward human breast cancer (MCF-7) cell lines. Compounds 57 and 58 displayed potent antimalarial activity against the resistant Plasmodium falciparum. The thorough studies on the stereochemistry of the different quassinoid diterpenoids provide a clear reference to the scientists who are interested on this field.     

Cytotoxic activity and constituents of the volatile oil from the roots of Patrinia scabra Bunge

The volatile oil from the roots of Patrinia scabra Bunge was isolated by steam distillation, and separated into four major fractions (Fr. A-D) by means of column chromatography. A total of 39 compounds (1-39) were identified by GC/MS analysis, and evaluated for their in vitro cytotoxic activities against human ovarian carcinoma cells (HO-8910) and human hepatoma cells (Bel-7402) (Table 1). Fr. A showed the strongest inhibitory effect on HO-8910 (IC50 = 21 microg/ml) and Bel-7402 cells (16 mcirog/ml), whereas Fr. B was the least active (>100 microg/ml). By comparison of the constituents of the four fractions, we assume that the cytotoxicity of the volatile oil of P. scabra is mainly due to the lignans and azulenes, rather than to caryophyllene oxide I (18). Our results suggest that the volatile oil of P. scabra possesses potent and tumor-specific cytotoxicity, and could serve as a possible candidate for future cancer chemotherapy.     

Xanthones from Tovomita pyrifolium

The wood of Tovomita pyrifolium (Guttiferae) contains the novel tovopyrifolins A [1,6-dihydroxy-7-methoxy-5-prenyl-6′,6′-dimethylpyrano (2′,3′:3,2)xanthone], B (1,5-dihydroxy-3,4-dimethoxyxanthone) and C (1,3,5-trihydroxy-2-methoxyxanthone) and also the known tovophyllins A and B [structure revised to 1,6-dihydroxy-5-prenyl-6′, 6′-dimethylpyrano(2′,3′:3,2)-6″,6″-dimethylpyrano(2″,3″:7,8)xanthone].     

Dichromenoxanthones from Tovomita brasiliensis

Two dichromenoxanthones [1,6-dihydroxy-6',6'-dimethylpyrano(2',3':3,4)-6',6'-dimethylpyrano(2',3':7,8)xanthone (brasilixanthone A) and 1,6-dihydroxy-6',6'-dimethylpyrano(2',3':2,3)-6',6'-dimethylpyrano(2',3':7,8)xanthone (brasilixanthone B)], along with betulinic acid, friedelin, sitosterol and stigmasterol were isolated from the roots and stems of Tovomita brasiliensis. Their structures were characterized on the basis of 1H and 13C NMR spectral data, including 2D NMR experiments.     

Cytotoxic naphthoquinones from roots of Lippia microphylla

A new prenylated naphthoquinone dimer named microphyllaquinone (1), a mixture of 6-methoxy- and 7-methoxy-naphtho[2,3-b]-furan-4,9-quinones (2a/2b) and tecomaquinone I (3), were isolated from roots of Lippia microphylla. The structures were elucidated by spectroscopic methods, including detailed 1D and 2D (COSY, NOESY, HMQC, HMBC) NMR data. Unpublished 13C NMR data of 2a and 2b are reported. The in vitro cytotoxic activity of the isolated compounds was tested against five types of tumor cells.     

Cytotoxic constituents of Achillea clavennae from Montenegro

Examination of the aerial parts of Achillea clavennae afforded eight guaianolides (1-8), three bisabolenes (9-11), four flavonols (12-15), sesamin (lignan) and isofraxidin (coumarin). The structures of the new compounds (2, 4, 5, 7 and 10) were determined by spectroscopic methods. The antiproliferative action of 2, 8, 9 and 12 were tested to HeLa, K562 and Fem-X human cancer cell lines. Guaianolides 2 (9alpha-acetoxyartecanin) and 8 (apressin) showed significant cytotoxic effects to all tested lines and inducumenone (9) exhibited a moderate activity. The most active was flavonol centaureidin (12), already known as cytotoxic compound.     

Cytotoxic ent-Abietane-type diterpenoids from the roots of Euphorbia ebracteolata

Euphoroids A–C (1–3), three new ent-abietane-type diterpenoids, together with ten known analogues (4–13) were obtained from the roots of Euphorbia ebracteolata. The structures of these compounds were determined by extensive spectroscopic data analysis, including UV, HRESIMS, 1D-, and 2D-NMR data. The inhibitory effects of compounds 1–13 on human cancer cells were determined using the MTT assay. The results revealed that new compounds 2 and 3 showed moderate cytotoxic activities against human cancer cell lines. Especially, compound 3 displayed selective cytotoxic effect agains cancer cell lines.     

Cytotoxic triterpenes from the aerial roots of Ficus microcarpa

Six triterpenes, 3beta-acetoxy-12,19-dioxo-13(18)-oleanene (1), 3beta-acetoxy-19(29)-taraxasten-20alpha-ol (2), 3beta-acetoxy-21alpha,22alpha-epoxytaraxastan-20alpha-ol (3), 3,22-dioxo-20-taraxastene (4), 3beta-acetoxy-11alpha,12alpha-epoxy-16-oxo-14-taraxerene (5), 3beta-acetoxy-25-methoxylanosta-8,23-diene (6) along with nine known triterpenes, 3beta-acetoxy-11alpha,12alpha-epoxy-14-taraxerene (7), 3beta-acetoxy-25-hydroxylanosta-8,23-diene (8), oleanonic acid (9), acetylbetulinic acid (10), betulonic acid (11), acetylursolic acid (12), ursonic acid (13), ursolic acid (14), and 3-oxofriedelan-28-oic acid (15) were isolated from the aerial roots of Ficus microcarpa, and their structures elucidated by spectroscopic methods. The in vitro cytotoxic efficacy of these triterpenes was investigated using three human cancer cell lines, namely, HONE-1 nasopharyngeal carcinoma, KB oral epidermoid carcinoma, and HT29 colorectal carcinoma cells. Compound 8 and pentacyclic triterpenes 9-15 possessing a carboxylic acid functionality at C-28 showed significant cytotoxic activities against the aforementioned cell lines and gave IC50 values in the range 4.0-9.4 microM.     

Cytotoxic diterpenoid quinonemethides from the roots of Pygmacopremna herbacea

Two new diterpenoid quinonemethides (1 and 2) along with two known compounds (3 and 4) were isolated from the hexane and ethyl acetate extracts of root nodules of Pygmacopremna herbacea. The structures of the new compounds were established by spectroscopic data interpretation. Single crystal X-ray diffraction analysis confirmed the structure of 1. The cytotoxic activities of these compounds were evaluated against A 549, HEPG2, MCF-7, PC-3 and HELA cancer cell lines. Compounds 4, 2 and 1 were shown very good cytotoxic activity.     

Cytotoxic and aromatic constituents from Salvia miltiorrhiza

As part of an ongoing study of traditional Chinese medicinal plants, the root tissue of Salvia miltiorrhiza was further investigated for its chemical constituents. Five naturally occurring products along with 13 known constituents were isolated from an ethyl acetate-soluble portion of its ethanol extract. Their structures were elucidated by means of spectroscopic methods. Some selected compounds were also evaluated for biological activity.     

Chemical constituents from the roots of Dendropanax chevalieri

Phytochemical investigation of the roots of Dendropanax chevalieri resulted in the isolation of a lignan glycoside (1), four phenylpropanoid derivatives (2–5), a long-chain fatty alcohol (6) and a triterpene (7). Except for 2, other compounds are being reported from D. chevalieri for the first time. Among them, compounds 1 and 6 were firstly isolated from the family Araliaceae. The chemotaxonomic significance of these compounds was summarized.     

Xanthones from Tovomita Excelsa

The trunk wood of Tovomita excelsa (Guttiferae) from north-eastern Brazil contains, besides betulinic acid, 1,5-dihydroxy-6-methoxyxanthone, 1,6-dihydroxy-5-methoxyxanthone, 5,6-dihydroxy-1-methoxyxanthone and 1,7- dihydroxy-6-methoxyxanthone.     

Bioactive constituents from roots of Bursera tonkinensis

Bioassay directed-fractionation led to isolation of 12 compounds from the roots of Bursera tonkinensis Guillaum (Burseraceae), including burselignan, bursephenylpropane, and burseneolignan. Of the 12 compounds, only 4'-demethyldesoxypodophyllotoxin exhibited significant cytotoxic activities against KB, Col2 and LNCaP cell lines.     

Six new constituents from the roots of Erythrina variegata

Three new isoflavonoids, eryvarins M-O (1-3), two new 2-arylbenzofurans, eryvarins P and Q (4 and 5), and a new 3-aryl-2,3-dihydrobenzofuran, eryvarin R (6), together with three known compounds, were isolated from the roots of Erythrina variegata. The structures of these compounds were established by spectroscopic analysis. Eryvarin R (6) is an unusual 3-aryl-2,3-dihydrobenzofuran derivative with a formyl (CHO) group. Eryvarin Q (5) showed potent antibacterial activity against methicillin-resistant Staphylococcus aureus.     

Chemical constituents from the roots of cultivated Ilex pubescens

Phytochemical study of butanol extract from the roots of cultivated Ilex pubescens Hook. et Arn. obtained nine ursane triterpenes (1–9), two oleanane triterpenes (10–11) and three phenylpropanoids (12–14). All of the compounds were determined on the basis of MS and NMR and comparison with literature. Among them, compounds 2 and 13 were isolated from I. pubescens for the first time, of which 13 was a new finding in the Aquifoliaceae family. Our present study exhibited the taxonomic relationships between I. pubescens and other species in genus Ilex and those between Aquifoliaceae and other families. Furthermore, the study suggested the cultivated I. pubescens may be as an alternative for those wild resource collected freshly from mountain.     

Cytotoxic dihydrobenzophenanthridine alkaloids from the roots of Macleaya microcarpa

Five dihydrobenzophenanthridine alkaloids, named as maclekarpine A-E, were isolated from the roots of Macleaya microcarpa, together with 10 known benzophenanthridine/dihydrobenzophenanthridine derivatives and a known amide. Their structures were determined on the basis of spectroscopic methods. The relative configuration of maclekarpine A was solved by X-ray single-crystal diffraction, which also contributed to the establishment of the relative configuration of maclekarpine B and C, as well as the assignment of the absolute configuration of maclekarpine A-C with aid of their CD curves. Cytotoxicity of the isolated compounds against five human tumor cell-lines was evaluated, with some having activity with IC₅₀ values ranging from 0.1 to 3.5 μM.     

Cytotoxic constituents of Viscum coloratum

Phytochemical studies on Viscum coloratum have resulted in the isolation of nineteen compounds. The structures of the isolated compounds were identified on the basis of 1D, 2D NMR and HR-ESI-Q-TOF-MS. Pachypodol (4) and ombuine (6) were characterized in the family Loranthaceae for the first time. 1,7-Bis(4-hydroxyphenyl)-1,4-heptadien-3-one (8) and 5-hydroxy-3,7,3'-trimethoxyflavone-4'-O-beta-D-glucoside (13) were two new natural compounds, which exhibited cytotoxic activities against four human tumour cell lines (HeLa, SGC-7901, MCF-7, and U251).     

Chemical constituents from the roots of Elephantopus scaber L.

A chemical investigation of the roots of Elephantopus scaber L. led to the isolation of thirteen compounds, including four sesquiterpenoids (5, 6, 7, 8), two phenols (1, 2), three triterpenoids (9, 10, 11), two caffeoylquinic acids (3, 4), one alkaloid (12), and one sterol (13). Among these molecules, compound 2 (2-butenoic acid, 3-methyl-[4-(1,5-dimethyl-4-hexenyl)-3-hydroxyphenyl] methyl ester) was identified for the first time from this species, while compounds 1 (curcuphenol) and 12 (patriscabratine) were isolated for the first time from the genus Elephantopus.     

金樱根化学成分的研究

金樱根为三金片的主要成分,但目前对于金樱根的化学成分和药理作用研究甚少。为了阐明金樱根的物质基础和生物活性,该研究采用硅胶、Sephadex LH-20、MCI gel CHP 20P等柱色谱以及HPLC半制备等方法,对金樱根(Rosa laevigata)的化学成分进行研究。结果表明:从中共分离得到9个化合物,经过波谱数据分析结合文献对照分别鉴定为儿茶素(1),表儿茶素(2),rosamultin(3),sericoside(4),2α,3α,19α,23-tetrahydroxy-urs-12-en-28-oic acid-3-O-β-D-glucopyranosyl ester(5),kaji-ichigoside F1(6),β-D-Glucopyranosyl 3β,19α-dihydroxy-2-oxo-urs-12-en-28-oate(7),胡萝卜苷(8),β-谷甾醇(9),其中化合物2、4、5、7为首次从该植物中分离得到。该研究结果为金樱根在功能医药领域的开发利用提供了理论依据。