Cytotoxic calanquinone A from Calanthe arisanensis and its first total synthesis.

Calanquinone A (1) was isolated from an EtOAc-soluble extract of Calanthe arisanensis through bioassay-guided fractionation. Its structure was identified by spectroscopic methods. Compound 1 showed potent cytotoxicity (EC(50)<0.

(-)-Xanthienopyran, a new inhibitor of superoxide anion generation by activated neutrophils, and further constituents of the seeds of Xanthium strumarium.

The dried seeds of XANTHIUM STRUMARIUM (Asteraceae) are used after thorough stir-frying as an ingredient in traditional Chinese medicines for relieving allergy. Two new compounds, xanthialdehyde ( 2) and (-)-xanthienopyran ( 7), as well as 26 known compounds were isolated in the present study. The structures of the isolates were elucidated by spectroscopic methods.

Camptothecinoids from the seeds of Taiwanese Nothapodytes foetida.

Two new alkaloids, 9-methoxy-18,19-dehydrocamptothecin (1) and 5- hydroxymappicine-20-O-beta-glucopyranoside (2a/2b as a racemic mixture), together with nine known compounds: camptothecin (3), 9-methoxy-camptothecin (4), 5-hydroxycamptothecin (5a/5b racemic mixture), 5-hydroxy-9-methoxycamptothecin (6a/6b racemic mixture), diosmetin (7), apigenin (8), apigenin-7-O-glucopyranoside (9), rosin (cinnamyl-O-beta-D-glucopyranoside) (10) and amarantholidoside IV (11) were isolated from the immature seeds of Nothapodytes foetida (Wight) Sleumer. The structures were elucidated by spectroscopic analyses. In the present research, compounds 1, 3, 4, 5a/5b and 6a/6b, also showed in vitro cytotoxicity against six cancer cell lines (HepG2, Hep3B, MDA-MB- 231, MCF-7, A549, and Ca9-22).

Lupane-type triterpenoids from Microtropis fokienensis and Perrottetia arisanensis and the apoptotic effect of 28-hydroxy-3-oxo-lup-20(29)-en-30-al.

Seven new lupane triterpenoids were isolated from bioactive methanol extracts of Microtropis fokienensis (1- 4) and Perrottetia arisanensis (4-7), along with 18 known compounds. The structures of the new compounds were elucidated on the basis of spectroscopic data analysis. All triterpenoids were evaluated for their in vitro cytotoxicity toward seven human cancer cell lines.

Bioactive cembrane diterpenoids of Anisomeles indica.

Five new cembrane-type diterpenoids with a trans-fused alpha-methylene-gamma-lactone (1-5), a new flavonoid glucoside (6), and 17 known compounds were isolated from a methanol extract of Anisomeles indica. The structures of 1-6 were elucidated by spectroscopic analysis, and the absolute configuration of compound 1 was determined using the modified Mosher's method. Compound 8 (4,5-epoxovatodiolide) exhibited cytotoxicity against a small panel of human cancer cell lines.

Tubocapsenolide A, a novel withanolide, inhibits proliferation and induces apoptosis in MDA-MB-231 cells by thiol oxidation of heat shock proteins.

Tubocapsenolide A (TA), a novel withanolide-type steroid, exhibits potent cytotoxicity against several human cancer cell lines. In the present study, we observed that treatment of human breast cancer MDA-MB-231 cells with TA led to cell cycle arrest at G(1) phase and apoptosis. The actions of TA were correlated with proteasome-dependent degradation of Cdk4, cyclin D1, Raf-1, Akt, and mutant p53, which are heat shock protein 90 (Hsp90) client proteins.

Mono-tetrahydrofuran annonaceous acetogenins from Annona squamosa as cytotoxic agents and calcium ion chelators.

Eight new mono-tetrahydrofuran (THF)-type annonaceous acetogenins, squafosacins B, C, F, and G (1-4), squadiolins A-C (5-7), and cis-annotemoyin-1 (8), as well as eight known annonaceous acetogenins, glabranin, annotemoyins-1 and -2, bullatencin, cis-bullatencin, and uvariamicins-I, -II, and -III, were isolated from the seeds of Annona squamosa by HPLC. The structures of all new isolates were elucidated by using spectroscopic and chemical methods. Squadiolins A (5) and B (6) showed ng/mL potency against human Hep G2 hepatoma cells and significant cytotoxic activity against human MDA-MB-231 breast cancer cells.

Inhibitory effects of 16-hydroxycleroda-3,13(14)E-dien-15-oic acid on superoxide anion and elastase release in human neutrophils through multiple mechanisms.

Reactive oxygen species and granule proteases produced by neutrophils contribute to the pathogenesis of inflammatory diseases. In this study, a cellular model in isolated human neutrophils was established to elucidate the anti-inflammatory functions of 16-hydroxycleroda-3,13(14)E-dien-15-oic acid (PL3S), a clerodane diterpenoid from Formosan Polyalthia longifolia var. pendula.

New benzoyl glucosides and cytotoxic pterosin sesquiterpenes from Pteris ensiformis Burm.

Three new compounds: 2R,3R-pterosin L 3-O-beta-D-glucopyranoside (1), beta-D-xylopyranosyl(1-->2)-7-O-benzoyl-beta-D-glucopyranoside (2) and 4-O-benzoyl-beta-D-xylo-pyranosyl(1-->2)-7-O-benzoyl-beta-D-glucopyranoside (3), together with nine known compounds, were isolated from the ethyl acetate extract of Pteris ensiformis. 5-[2-Hydroxyethylidene]-2(5H)-furanone (4), which had been synthesized, was isolated from natural sources for the first time. The structures of all isolated compounds were determined on the basis of mass and spectroscopic evidence.

Antiplatelet aggregation coumarins from the leaves of Murraya omphalocarpa.

Using a bioactivity-guided fractionation method, two coumarins: minumicroline acetonide (1) and epimurpaniculol senecioate (2), were isolated from the leaves of Murraya omphalocarpa Hayata (Rutaceae). Compound 1 had been previously synthesized and was now isolated from natural sources for the first time, and compound 2, possessing a negative optical rotation value, is new. The structures and their stereochemistry were fully elucidated on the basis of spectroscopic and X-ray crystallographic techniques.

Safflower extract: a novel renal fibrosis antagonist that functions by suppressing autocrine TGF-beta.

Progressive renal disease is characterized by the accumulation of extracellular matrix proteins in the renal interstitium. Hence, developing agents that antagonize fibrogenic signals is a critical issue facing researchers. The present study investigated the blood-circulation-promoting Chinese herb, safflower, on fibrosis status in NRK-49F cells, a normal rat kidney interstitial fibroblast, to evaluate the underlying signal transduction mechanism of transforming growth factor-beta (TGF-beta), a potent fibrogenic growth factor.

New cyclic peptides from the seeds of Annona squamosa L. and their anti-inflammatory activities.

Two new cyclic peptides, cyclosquamosin H ( 1) and I ( 2), together with six known cyclic peptides, squamin A ( 3), squamin B ( 4), cyclosquamosin A ( 6), cyclosquamosin D ( 7), cyclosquamosin E ( 8), and cherimolacyclopeptide B ( 9), were isolated from the seeds of Annona squamosa. All structures were confirmed by 2D nuclear magnetic resonance, chemical evidence, and electrospray ionization-mass spectromotry/mass spectrometry (ESI-MS/MS). Compound 9 was isolated from this plant for the first time.

New constituents from stems of Artabotrys uncinatus.

Two new compounds, 4,5-dioxoartacinatine (1) and 24-methylenelanosta-7,9(11)-diene-3-one (2), together with thirty known compounds were isolated and characterized from the stems of Artabotrys uncinatus. Structures of the new compounds were determined by spectral analysis.

Cytotoxic sesquiterpene lactones from Pseudoelephantopus spicatus.

Five new sesquiterpene lactones, spicatolides D-H (1-5), along with four known compounds, pitocarphin D (6), 8 alpha-acetoxy-10 alpha-hydroxy-13-O-methylhirsutinolide (7), spicatolide A (8), and 13-O-methylvernojalcanolide 8-O-acetate (9), were isolated from an ethyl acetate extract of the aerial parts of Pseudoelephantopus spicatus. The structures of the new compounds were elucidated on the basis of spectroscopic data interpretation. All of the compounds isolated were evaluated for their cytotoxic effects against five human cancer cell lines.

Cytotoxic ent-abietane diterpenes from Gelonium aequoreum.

Seventeen ent-abietane diterpenes, including gelomulides K-X (1-14), and three known compounds, were isolated from a dichloromethane-soluble extract of Gelonium aequoreum through bioassay-guided fractionation. Their structures were identified by spectroscopic methods, and stereochemistry was confirmed by X-ray crystallographic analysis, CD spectral data, and Mosher's method. The isolates were evaluated for in vitro cytotoxic activity, and compounds 1 and 3 showed moderate cytotoxicity against lung (A549), breast (MDA-MB-231 and MCF7), and liver (HepG2) cancer cell lines.

First total synthesis of protoapigenone and its analogues as potent cytotoxic agents.

Protoapigenone (1), isolated from Thelypteris torresiana, previously showed significant cytotoxic activity against five human cancer cell lines. In a continued structure-activity relationship study, the first total synthesis and modification of 1 were achieved. All synthesized compounds and related intermediates were evaluated for cytotoxic activity against five human cancer cell lines, HepG2, Hep3B, MDA-MB-231, MCF-7, and A549.

A bioactive withanolide Tubocapsanolide A inhibits proliferation of human lung cancer cells via repressing Skp2 expression.

Withanolides are generally defined as C(28) steroidal lactones built on an intact or rearranged ergostane skeleton and have been shown to exhibit antiproliferative activity on various types of cancer cells. In this study, we investigated the effect of a new withanolide Tubocapsanolide A isolated from Tubocapsicum anomalum and addressed its molecular action. Tubocapsanolide A inhibited proliferation of A549, H358, and H226 human lung cancer cells via induction of G(1) growth arrest.

Cytotoxic withanolides from Tubocapsicum anomalum.

Fifteen new withanolides (1-8, 11-17) and two known withanolides, withanolide D (9) and 17alpha-hydroxywithanolide D (10), were isolated from the stems, roots, and leaves of Tubocapsicum anomalum using bioassay-directed fractionation. The structures were determined by spectroscopic and chemical methods, and the absolute configurations were established by CD analysis and by the Mosher ester method. The structure of 1 and 3 were further confirmed by X-ray crystallographic analysis.

Novel flavonoids of Thelypteris torresiana.

In our continuing research on cytotoxic components from the Formosan pteridophyte Thelypteris torresiana (GAUD.) ALSTONONE, two new compounds, a novel flavonoid, flavotorresin (1), and a flavonoid diglycoside, multiflorin C (2), along with five known compounds, were isolated. The structural elucidation was established on the basis of spectroscopic data analysis.

CD36 is a novel and potential anti-fibrogenic target in albumin-induced renal proximal tubule fibrosis.

Albumin is not only a risk factor for diabetic nephropathy (DN), but also a therapeutic target. Hence, scientists have long sought ways to elucidate the interactions between albumin and diabetic renal tubule fibrosis. CD36, a surface receptor for thrombospondin-1, has been reported to interact with latent transforming growth factor-beta1 (TGF-beta1) and activate its fibrogenic bioactivity.

Cytotoxic triterpenoids from the leaves of Microtropis fokienensis.

Five new triterpenoids, microfokienoxanes A-D (1-4) and 3beta,28-dihydroxy-11alpha-methoxyurs-12-ene (5), were isolated and identified from the leaves of Microtropis fokienensis, along with nine known compounds. The structures of the new compounds were elucidated by spectroscopic methods. The compounds obtained in this investigation were evaluated against a small panel of human cancer cell lines for cytotoxicity.

New sesquiterpene lactones from the aerial parts of Pseudoelephantopus spicatus.

Two new sesquiterpene lactones, spicatolide C (1) and spicatocadinanolide A (2), have been isolated along with the known piptocarphol isomers (3, 4) and one eudismane type sesquiterpene (5) from the EtOAc extract of the aerial parts of Pseudoelephantopus spicatus. The structures and the relative stereochemistries of the new metabolites were determined by spectroscopic methods.

Anti-inflammatory and cytotoxic diterpenes from formosan Polyalthia longifolia var. pendula.

A new clerodane diterpenoid 16-hydroxycleroda-13-ene-15,16-olide-3-one (1) was isolated from the bark of Polyalthia longifolia var. pendula, along with 23 known compounds and phytosteroids. Among these compounds, 5 - 7, 10, and 24 were obtained for the first time from the family Annonaceae .

Effect of isoquinoline alkaloids of different structural types on antiplatelet aggregation in vitro.

Forty-one isoquinoline alkaloids were tested for antiplatelet aggregation effects. Among them, (-)-discretamine (6), protopine (7), ochotensimine (18), O-methylarmepavinemethine (23), lindoldhamine (25), isotetrandrine (26), thalicarpine (27), papaverine (28), and D-(+)- N-norarmepavine (32) exhibited significant inhibitory activity towards adenosine 5'-diphosphate (ADP)-, arachidonic acid (AA)-, collagen-, and/or platelet-activating factor (PAF)-induced platelet aggregation. The results are discussed on the basis of structure-activity relationships.

Anti-AIDS agents 69. Moronic acid and other triterpene derivatives as novel potent anti-HIV agents.

In a continuing structure-activity relationship study of potent anti-HIV agents, seven new triterpene derivatives were designed, synthesized, and evaluated for in vitro antiviral activity. Among them, moronic acid derivatives 19, 20, and 21 showed significant activity in HIV-1 infected H9 lymphocytes. Compounds 19 and 20 were also evaluated against HIV-1 NL4-3 and drug resistant strains in the MT-4 cell line.