Stilbenes with potent cytotoxicity from the seedcases of Paeonia suffruticosa Andrews.

Stilbenes (based on the 1,2-diphenylethylene skeleton) are a class of plant polyphenols with rich structural and bioactive diversity. Twenty-six stilbenes, including five undescribed compounds (7,8-dioxy-4,3',5'-trihydroxystilbene, trans-13'-methoxygnetin H, suffruticosol E, paestibenetrimerols A and B), were isolated from the seedcases of Paeonia suffruticosa Andrews. Their structures were elucidated by spectroscopic analyses and comparison with previously reported data.

(±)-Pheharmines A-B, two pairs of racemic alkaloids with a morpholino[4,3,2-]β-carboline core, from the roots of .

Two pairs of unprecedented β-carboline-phenylpropanoid heterogeneous alkaloids, (±)-pheharmines A-B (1-4), characterized by a morpholino[4,3,2-]β-carboline core with two chiral centers, were isolated from the roots of . The structures, including their absolute configurations, were identified using spectroscopic analyses and electronic circular dichroism (ECD) calculations. The biosynthetic hypothesis for the formation of pheharmines A-B was proposed.

Cephalotaxine-type and homoerythrina-type alkaloids with antiproliferative effects from .

Twenty-two cephalotaxine-type and ten homoerythrina-type alkaloids, including seven previously undescribed ones, were isolated from the twigs and leaves and the seed kernels of . Their structures were established by spectroscopic analysis, single crystal X-ray diffraction, and ECD calculation methods. Cephalofortunine A β--oxide (1) is the first nitrogen-oxidized homoerythrina-type alkaloid.

Cephalotaxine-type alkaloids with antiproliferation effects from the branches and leaves of Cephalotaxus fortunei var. alpina.

Eight cephalotaxine-type alkaloids (1-8), including two new compounds cephafortunines A and B (1-2), were isolated from the branches and leaves of Cephalotaxus fortunei var. alpina. Their structures were identified by a series of spectroscopic methods (MS, UV, IR, 1D, and 2D NMR) and comparison with the reported data of known analogs.

Pegaharmols A-B, Axially Chiral β-Carboline-quinazoline Dimers from the Roots of .

Two nonbiaryl axially chiral β-carboline-quinazoline dimers, pegaharmols A () and B (), were isolated from the roots of . Their planar structures were elucidated by the spectroscopic methods of high-resolution mass spectrometry and 1D and 2D nuclear magnetic resonance (NMR). The stereochemistry was established by a comparison between the experimental data of NMR and electronic circular dichroism and the computed data by quantum mechanical calculations.

Bioassay- and Chemistry-Guided Isolation of Scalemic Caged Prenylxanthones from the Leaves of Garcinia bracteata.

With bioassay- and chemistry-guided fractionation, seven new caged prenylxanthones including two scalemic mixtures, epiisobractatin (1), 13-hydroxyisobractatin (2), 13-hydroxyepiisobractatin (3), 8-methoxy-8,8a-dihydrobractatin (4), 8-ethoxy-8,8a-dihydrobractatin (5), garcibracteatone (6), and 8-methoxy-8,8a-dihydroneobractiatin (7), and the eight known compounds 8-15 were isolated from the leaves of Garcinia bracteata. The structures were unambiguously elucidated through analysis of spectroscopic data. The 2D structures and relative configurations of 1 and 5 were confirmed by X-ray crystallographic analysis.

Antiproliferative Dimeric Aporphinoid Alkaloids from the Roots of Thalictrum cultratum.

Inspired by the intriguing structures and bioactivities of dimeric alkaloids, 11 new thalifaberine-type aporphine-benzylisoquinoline alkaloids, thalicultratines A-K, a tetrahydroprotoberberine-aporphine alkaloid, thalicultratine L, and five known ones were isolated from the roots of Thalictrum cultratum. Their structures were defined on the basis of NMR and HRESIMS data. The antiproliferative activities of compounds 1-17 were evaluated against human leukemia HL-60 and prostate cancer PC-3 cells.

Neobraclactones A-C, three unprecedented chaise longue-shaped xanthones from Garcinia bracteata.

Neobraclactones A-C (1-3), featuring an unprecedented further rearranged prenylxanthone skeleton with a unique octahydro-2H-1,3-dioxacyclopenta[c,d]inden-2-one scaffold, along with their biosynthesis-related known compound neobractatin (4), were isolated from the leaves of Garcinia bracteata. Their structures with absolute configurations were determined by extensive analyses of spectroscopic data and ECD calculations. Compounds 1 and 2 showed significant growth inhibition activities against the human leukaemia HL-60 and K562 cell lines with GI values from 0.

Structurally Diverse Alkaloids from the Seeds of Peganum harmala.

Investigation of the alkaloids from Peganum harmala seeds yielded two pairs of unique racemic pyrroloindole alkaloids, (±)-peganines A-B (1-2); two rare thiazole derivatives, peganumals A-B (3-4); six new β-carboline alkaloids, pegaharmines F-K (5-10); and 12 known analogues. Their structures, including stereochemistry, were elucidated through spectroscopic analyses, quantum chemistry calculations, and single-crystal X-ray diffraction. Notably, the incorporation of pyrrole and indole moieties in peganines A-B, thiazole fragments in peganumals A-B, and a C-1 α,β-unsaturated ester motif in pegaharmine F (5) are all rare, and their presence in the genus Peganum were demonstrated for the first time.

A Series of β-Carboline Alkaloids from the Seeds of Peganum harmala Show G-Quadruplex Interactions.

In this study, we screened 17 medicinal plants for binding activity to G-quadruplex d(TTGGGTT)4 by (1)H NMR spectroscopy and found that the crude extract of Peganum harmala L. seeds showed the most potential binding activity. Subsequently, (1)H NMR- and bioassay-guided isolation of the extract of P.

Two Pairs of Enantiomeric Alkaloid Dimers from Macleaya cordata.

Two pairs of enantiomeric alkaloid dimers, (±)-macleayins A (1) and B (2), representing a novel dimerization pattern of two different types of alkaloids via a C-C σ-bond, were isolated from the aerial parts of Macleaya cordata. The enantiomeric separation was achieved by chiral chromatography. Their structures and stereochemistry were determined by the analysis of extensive spectroscopic data, electronic circular dichroism calculation, and single-crystal X-ray diffraction data.

Quinolone and indole alkaloids from the fruits of Euodia rutaecarpa and their cytotoxicity against two human cancer cell lines.

Four quinolone alkaloids (1-4) and three indole alkaloids (20-22), together with 30 known alkaloids (5-19, 23-37), were isolated from the fruits of Euodia rutaecarpa. Their structures were established by spectroscopic analyses. The in vitro cytotoxic activities of these alkaloids against leukaemia HL-60 and prostate cancer PC-3 cell lines were evaluated.

Peganumine A, a β-carboline dimer with a new octacyclic scaffold from Peganum harmala.

Peganumine A (1), a new dimeric β-carboline alkaloid characterized by a unique 3,9-diazatetracyclo[6.5.2.

Synthesis and biological evaluation of substituted 1,2,3-benzotriazines and pyrido[3,2-d]-1,2,3-triazines as inhibitors of vascular endothelial growth factor receptor-2.

A novel series of substituted 1,2,3-benzotriazines and pyrido[3,2-d]-1,2,3-triazines were synthesized. The abilities of these compounds to inhibit the VEGFR-2 kinase activity and the proliferation of human microvascular endothelial cells (MVECs) were determined. 6-Methoxy-4-substituted-1,2,3-benzotriazines and 4-substituted-6-chloro-pyrido[3,2-d]-1,2,3-triazines have the abilities of inhibiting the VEGFR-2 kinase activity, but only the 4-substituted-6-chloro-pyrido[3,2-d]-1,2,3-triazines exhibit good growth inhibitory effects on MVECs.

Five novel naphthylisoquinoline alkaloids with growth inhibitory activities against human leukemia cells HL-60, K562 and U937 from stems and leaves of Ancistrocladus tectorius.

Two new 7,6'-coupled naphthylisoquinolines, namely ancistrotectorines A (1) and B (2), two new 5,3'-coupled naphthylisoquinolines, namely ancistrotectorines C (3) and D (4), and one new 7,8-coupled naphthylisoquinoline, namely ancistrotectorine E (5), together with 9 known naphthylisoquinoline alkaloids, hamatine (6), ancistrobertsonine B (7), ancistrocladinine (8), hamatinine (9), ancistrotanzanine A (10), ancistrotanzanine B (11), ancistrotectoriline B (12), 7-epi-ancistrobrevine D (13), and ancistrotectorine (14), were isolated from the 70% EtOH extract of Ancistrocladus tectorius. Their structures were elucidated based on the extensive analysis of spectroscopic data (1D, 2D NMR and MS). Compound 5 exhibited inhibitory activities against HL-60, K562 and U937 cell lines with IC50 values of 1.

Triterpene saponins from Clematis mandshurica and their antiproliferative activity.

Six new triterpene saponins, clematomandshurica saponins F-K (1-6), together with a known compound (7), were isolated from the roots and rhizomes of Clematis mandshurica. Their structures were elucidated on the basis of spectroscopic evidence and hydrolysis. Compounds 5-7 exhibited antiproliferative effects against PC-3 human prostate cancer cells with GI50 values of 1.

Five new 3,4-seco-lanostane-type triterpenoids with antiproliferative activity in human leukemia cells isolated from the roots of Kadsura coccinea.

Five new 3,4-seco-lanostane-type triterpenoids, seco-coccinic acids G-K (1-5), and a known compound, seco-coccinic F, were isolated from the roots of Kadsura coccinea (Lem.) A. C.

2,5-diketopiperazines from the marine-derived fungus Aspergillus fumigatus YK-7.

Five new diketopiperazines, prenylcyclotryprostatin B (1), 20-hydroxycyclotryprostatin B (2), 9-hydroxyfumitremorgin C (3), 6-hydroxytryprostatin B (4), and spirogliotoxin (5), were isolated from the marine-derived fungus Aspergillus fumigatus YK-7, along with nine known compounds, 6-14. Their structures were elucidated by spectroscopic methods, and their antiproliferative effects on human leukemic monocyte lymphoma U937 and human prostate cancer PC-3 cell lines were assessed in vitro. Compounds 10, 12, and 13 exhibited significant cell growth-inhibitory activities against U937 cell line, with the IC(50) values of 1.

Xanthones from the stem bark of Garcinia bracteata with growth inhibitory effects against HL-60 cells.

Five xanthones, 1,4,5,6-tetrahydroxyxanthone (1) and bracteaxanthones III-VI (2-5) together with twenty-six known compounds (6-31), were isolated from the ethanol extract of the stem bark of Garcinia bracteata. Their structures were elucidated via spectroscopic analyses. Growth inhibitory activities of these compounds against the human leukaemic HL-60 cell line were measured in vitro.

A bisamide and four diketopiperazines from a marine-derived Streptomyces sp.

A new bisamide N₁-acetyl-N₇-phenylacetyl cadaverine (1) and a series of diketopiperazines including a new diketopiperazine cyclo(2-hydroxy-Pro-R-Leu) (2), together with a new natural product cyclo(4-hydroxy-S-Pro-S-Trp) (3) and two known leucine-based diketopiperazines cyclo(4-hydroxy-R-Pro-S-Leu) (4) and cyclo (S-Pro-R-Leu) (5), were isolated from ethyl acetate extract of a fermentation broth of a marine-derived Streptomyces sp. Their structures were elucidated by the interpretation of spectroscopic analysis. The antitumor activities of compounds 1-3 against HL-60 cell lines were tested by MTT assay.

Three new phenolic compounds from the lichen Thamnolia vermicularis and their antiproliferative effects in prostate cancer cells.

Three new phenolic compounds, thamnoliadepsides A (1), B (2), and thamnolic acid A (3), and seven known compounds, everninic acid (4), baeomycesic acid (5), β-orcinol (6), β-resorcylic acid (7), ethyl orsellinate (8), squamatic acid (9), and vermicularin (10), were isolated from the lichen Thamnolia vermicularis (Sw.) Ach. ex Schaerer.

Two new triterpenoids from the resin of Boswellia carterii.

Two new triterpenoids, 3-oxotirucalla-7,9(11),24-trien-21-oic acid (1) and 18Hα,3β,20β-ursanediol (2), along with 15 known triterpenes, α-amyrin, α-boswellic acid, β-boswellic acid, acetyl α-boswellic acid, acetyl β-boswellic acid, 9,11-dehydro-β-boswellic acid, 9,11-dehydro-α-boswellic acid, acetyl 11α-methoxy-β-boswellic acid, 11-keto-β-boswellic acid, acetyl 11-keto-β-boswellic acid, acetyl α-elemolic acid, 3β-hydroxytirucalla-8,24-dien-21-oic acid, elemonic acid, 3α-hydroxytirucalla-7,24-dien-21-oic acid, and 3α-hydroxytirucall-24-en-21-oic acid, were isolated from the resin of Boswellia carterii Birdw.

Triterpenoids from Calophyllum inophyllum and their growth inhibitory effects on human leukemia HL-60 cells.

A new friedelane-type triterpene (1), along with seven known triterpenoids, was isolated from the stems and leaves of Calophyllum inophyllum Linn. Their structures were established as 3beta, 23-epoxy-friedelan-28-oic acid (1), friedelin (2), epifriedelanol (3), canophyllal (4), canophyllol (5), canophyllic acid (6), 3-oxo-friedelan-28-oic acid (7), and oleanolic acid (8) by spectroscopic methods (NMR, EI-MS). The growth inhibitory effects of these triterpenoids on human leukemia HL-60 cells were determined.

Design and synthesis of novel 2-phenylaminopyrimidine (PAP) derivatives and their antiproliferative effects in human chronic myeloid leukemia cells.

A series of novel 2-phenylaminopyrimidine (PAP) derivatives structurally related to STI-571 were designed and synthesized. The abilities of these compounds to inhibit proliferation were tested in human chronic myeloid leukemia K562 cells. (E)-3-(2-bromophenyl)-N-[4-methyl-3-(4-pyridin-3-yl-pyrimidin-2-ylamino)phenyl]acrylamide(12d) was the most effective cell growth inhibitor and was 3-fold more potent than STI-571.

Two novel triterpenoids with antiproliferative and apoptotic activities in human leukemia cells isolated from the resin of Garcinia hanburyi.

Two new triterpenoids, 2alpha-hydroxy-3beta-O-acetyllup-20(29)-en-28-oic acid (1) and 3- O-(4'- O-acetyl)-alpha- L-arabinopyranosyloleanolic acid ( 2), together with two known triterpenoids, betulinic acid ( 3) and messagenic acid ( 4) were isolated from the CHCl3 extract of Garcinia hanburyi resin. The structures were elucidated by analysis of the NMR spectroscopic data. The antiproliferative effects and the apoptosis induction abilities of compounds 1 and 2 were determined in four human leukemia cell lines.