Cytotoxic prenylated flavonoids from Morus alba

A phytochemical fractionation of the methanol extract of the Morus alba leaves led to the isolation of eleven flavonoids (1–11). The structure of the new 3′-geranyl-3-prenyl-2′,4′,5,7-tetrahydroxyflavone (1) was elucidated by means of spectroscopic methods. The cytotoxicity of the isolated compounds against human cervical carcinoma HeLa, human breast carcinoma MCF-7, and human hepatocarcinoma Hep3B cells was evaluated. Of note, morusin (9) was the most potent with an IC₅₀ value of 0.64 μM against HeLa cells.     

Andalasin A, a new stilbene dimer from Morus macroura

A new stilbene dimer, andalasin A (1), together with the known stilbene oxyresveratrol and the 2-arylbenzofuran glycoside mulberroside C, have been isolated from the wood of Morus macroura. The structure of the new compound was elucidated on the basis of spectroscopic data. Compound 1 shows weak antinematodal and moderate antifungal properties.     

A new norlignan from Taxodium ascendens

A new norlignan, (2R,3R,4S,5S)-2,4-bis(4-hydroxyphenyl)-3,5-dihydroxy-tetrahydropyran (1), together with 9 known compounds were isolated from the branches and leaves of Taxodium ascendens. Their structures were mainly determined on the basis of MS, IR, 1D and 2D NMR spectral evidences. Methanol extract showed inhibitory activity on carbonic anhydrase II with an IC₅₀ value of 4.27 µg/ml, acetone extract and methanol extract inhibited activity of cathepsin B with IC₅₀ values of 2.12 and 3.71 µg/ml, respectively.     

A new abietane diterpene from Glyptostrobus pensilis

A new abietane diterpene, glypensin A (1) and four known compounds, 12-acetoxy-ent-labda-8(17), 13E-dien-15-oic acid (2), quercetin 3-O-α-L-arabinofuranoside (3), quercetin 3-O-β-D-galactopyranoside (4), β-sitosterol (5) were isolated from the branches and leaves of Glyptostrobus pensilis (Staut.) Koch. Their structures were determined by MS, 1D- and 2D-NMR means. Compound 1 showed cytotoxicity on human chronic myeloid leukemia cell line K562 (IC₅₀ = 21.2 μM).     

In vivo hypoglycemic effects of phenolics from the root bark of Morus alba

Moracin M (1), Steppogenin-4′-O-β-D-glucosiade (2), Mullberroside A (3) were isolated from the root bark of Morus alba L. and identified by spectral evidence. Compounds 1, 2 and 3 were studied in hypoglycemic effects on alloxan-diabetic mice. The results showed that compounds 1, 2 and 3 all produced hypoglycemic effects. The compound 2 in a dose of 50 mg/kg exerted significant effect (p < 0.05), 2 and 3 in a dose of 100 mg/kg exerted obviously effect (p < 0.01). Meantime, the compound 1 in a dose of 100 mg/kg can make the fasting blood glucose level have decreasing tendency.     

A new triterpenoid from Azadirachta indica

A new triterpenoid, 1α,7α-diacetoxyapotirucall-14-ene-3α,21,22,24,25-pentaol (1), and the two known compounds odoratone (2) and 2β,3β,4β-trihydroxypregnan-16-one (3) were isolated from a methanolic extract of the seed kernels of Azadirachta indica. Their structures were elucidated on the basis of spectral methods.     

A new cerebroside from Gynura divaricata

A new cerebroside, 1-O-β-d-glucopyranosyl-(2S,3S,4R,10E)-2-[(2′R)-2′-hydroxyltricosanoyl-amino]-10-octadecene-1,3,4-triol was isolated from the aerial parts of Gynura divaricata DC.     

A new kaurane diterpene dimer from Parinari campestris

A new kaurane diterpene dimer, 15-oxozoapatlin-13alpha-yl-10'alpha,16'alpha-dihydroxy-9'alpha-methyl-20'-nor-kauran-19'-oic acid gamma-lactone-17'-oate (1), together with the known 13-hydroxy-15-oxozoapatlin (2), 10alpha,13alpha,16alpha,17-tetrahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid gamma-lactone (3), 2alpha,10alpha,13alpha,16alpha,17-pentahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid (19,10)-lactone (4), 3alpha,10alpha,13alpha,16alpha,17-pentahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid gamma-lactone (5), and 1beta,16alpha,17-trihydroxy-ent-kaurane (6) were isolated from the leaves of Parinari campestris and identified on the basis of detailed spectral analysis, including 2D NMR spectrometry and ESI-MS.     

A new C-methylated flavonoid glycoside from Pinus densiflora

A new C-methyl flavonol glycoside, 5,7,8,4'-tetrahydroxy-3-methoxy-6-methylflavone 8-O-beta-D-glucopyranoside (1), has been isolated from the needles of Pinus densiflora, together with kaempferol 3-O-beta-(6"-acetyl)-galactopyranoside.     

A new arylnaphthalene lignan from Knema furfuracea

A new arylnaphthalene lignan, named furfuracin (1), was isolated from the leaves of Knema furfuracea (Myristicaceae), whereas 7 known compounds including (+)-trans-1,2-dihydrodehydroguaiaretic acid, fragransin A₂, biochanin A, gingkolic acid, anarcardic acid, 2-hydroxy-6-(12-phenyldodecyl)-benzoic acid and 2-hydroxy-6-(12-phenyldodecen-8′Z-yl)-benzoic acid were obtained from its stems. The structure of the new lignan was established by analysis of spectroscopic data (UV, IR, MS and NMR).     

A new ent-kaurane diterpenoid from Rabdosia pseudo-irrorata

A new kaurenoid, ent-3β,7α,14β-trihydroxykaur-16-ene-12,15-dione (1), named pseurata G, was isolated from the ethanol extract of the whole plant of Rabdosia pseudo-irrorata.     

Two new flavonoids from Retama raetam

Two new flavones were isolated from the aerial parts of Retama raetam subsp. raetam. Their structures were established as luteolin 4′-O-neohesperidoside (1) and 5,4′-dihydroxy-(3″,4″-dihydro-3″,4″-dihydroxy)-2″,2″-dimethylpyrano-(5″,6″:7,8)-flavone (2) by means of spectroscopic methods. Also present was ephedroidin (4′,5,7-trihydroxy-8-(2-hydroxy-3-butenyl)-flavone).     

A new lupane caffeoyl ester from Hippocratea volubilis

The extract of the rootbark of Hippocratea volubilis afforded a new triterpene caffeoyl ester, lupeol caffeate (1). Its structure was determined by means of spectroscopic evidence.     

A new biflavonoid from Daphniphyllum angustifolium Hutch

An investigation of the flavonoids in Daphniphyllum angustifolium Hutch. resulted in the identification of a new biflavonoid, 5,7,4′-trihydroxyflavan (2α→O→7, 4α→8) kaempferol (1), together with five known flavonoids. Their structures were determined by spectroscopic method.     

A new flavonoid from the aerial part of Thalictrum atriplex

A new flavone glycoside, identified as kaempferol 3-O-[3′″-acetyl-α- -arabinopyranosyl-(1′″–6″)]-β- -glucopyranoside (1), has been isolated from the aerial part of Thalictrum atriplex.     

Artoindonesianin L, a new prenylated flavone with cytotoxic activity from Artocarpus rotunda

A new prenylated flavone, named artoindonesianin L (1), was isolated from Artocarpus rotunda (Hout) Panzer (Moraceae). Its structure was elucidated as on the basis of spectroscopic evidence. Along with this new compound, four known phenolic compounds were also isolated from this plant and identified as artonins M (2) and E (3), cycloartobiloxanthone (4) and artonin O (5). All these compounds showed significant cytotoxicity against murine P388 leukemia cells.     

Two novel proaporphine–tryptamine dimers from Roemeria hybrida

Roemeria hybrida yielded two novel proaporphine-tryptamine N-oxides, (-)-roehybridine alpha-N-oxide (1) and (-)-roehybramine beta-N-oxide (2). NMR data allowed a facile assignment of these proaporphine-tryptamine dimers into different stereochemical subgroups.     

Aripuanin, a megastigmane skeleton from Ficus aripuanensis

The isolation and NMR spectra of aripuanin (1), a sesquiterpene from Ficus aripuanensis, are reported.     

A new 2-arylbenzofuran from the root bark of Chinese Morus cathayana

A new 2-arylbenzofuran, sanggenofuran B (3',5'-dihydroxy-6-methoxy-4'-prenyl-2-arylbenzofuran), from the root bark of Chinese Morus cathayana is reported.     

Two new biphenanthrenes with cytotoxic activity from Bulbophyllum odoratissimum

Two new dimeric phenanthrenes, bulbophythrins A (1) and B (2), were isolated from Bulbophyllum odoratissimum. Their structures were elucidated by HR-ESI-MS, 1D and 2DNMR spectroscopy. They were evaluated in vitro for their inhibitory ability against the growth of human leukemia cell lines K562 and HL-60, human lung adenocarcinoma A549, human hepatoma BEL-7402 and human stomach cancer SGC-7901. Both compounds showed significant cytotoxicity against the tested cell lines. Compound 1 exhibited some selectivity against HL-60 and BEL-7402 with IC₅₀ values of 1.27 × 10^− 3 and 1.22 × 10^− 3 µmol/ml respectively, whereas 2 was most active against A549 with IC₅₀ value of 1.18 × 10^− 3 µmol/ml.