Resorcinol derivatives from Ardisia maculosa

Besides a series of known sterols and triterpenoids, a new resorcinol (1) and a known resorcinol (2) have been isolated from ethanol extract of Ardisia maculosa for the first time. The structures of these resorcinol derivatives were elucidated as 2-methyl-5-(Z-heptadec-8-enyl) resorcinol and 5-Z-heptadec-8-enyl) resorcinol by HRESI-MS, NMR ((1)H, (13)C, HSQC, HMBC) experiments. In our in vitro assay, compounds 1 and 2 showed no antimicrobial activities, however, compound 2 exhibited cytotoxity activity against human cancer cell line with GI(50) value of 2.14 x 10(- 4) mmol/ml.     

Resorcinol derivatives from Ardisia maculosa

Besides a series of known sterols and triterpenoids, a new resorcinol (1) and a known resorcinol (2) have been isolated from ethanol extract of Ardisia maculosa for the first time. The structures of these resorcinol derivatives were elucidated as 2-methyl-5-(Z-heptadec-8-enyl) resorcinol and 5-Z-heptadec-8-enyl) resorcinol by HRESI-MS, NMR (¹H, ¹³C, HSQC, HMBC) experiments. In our in vitro assay, compounds 1 and 2 showed no antimicrobial activities, however, compound 2 exhibited cytotoxity activity against human cancer cell line with GI₅₀ value of 2.14 × 10^- 4 mmol/ml.     

Bioassay-Guided Isolation of a Potent Platelet-Activating Factor Antagonist Alkenylresorcinol from Ardisia elliptica

In the course of our search for novel platelet-activating factor (PAF) antagonists from medicinal plants, the methanol extract of the leaves of Ardisia elliptica Thunb. was investigated for its inhibitory effects on PAF receptor binding to rabbit platelets using ³H-PAF as a ligand. The methanol extract showed inhibitory activity of 53.9% and its ethyl acetate, n-butanol, and methanol fractions exhibited 48.6%, 39.0%, and 22.0% inhibition, respectively. Bioassay-guided fractionation of the ethyl acetate fraction led to the isolation of a new alkenylresorcinol, 5-(Z-heptadec-4′-enyl)resorcinol, together with 5-pentadecylresorcinol. The alkenylresorcinol showed a strong inhibition with an IC₅₀ value of 7.1 µM. The structures of the compounds were elucidated by spectroscopic techniques.     

Parathesilactones and Parathesiquinones from Branches of Parathesis amplifolia.

Abstract

Three new lactone derivatives, (3E.)-5,6-dihydroxy-3-(3-hydroxy-4-nonyl-5-oxofuran-2(5H.)-ylidene)-7-nonyl-1-benzofuran-2(3H.)-one (1), (3E.)-5,6-dihydroxy-3-(3-hydroxy-4-decyl-5-oxofuran-2(5H.)-ylidene)-7-decyl-1-benzofuran-2(3H.)-one (2), and (3E.)-5,6-dihydroxy-3-(3-hydroxy-4-undecyl-5-oxofuran-2(5H.)-ylidene)-7-undecyl-1-benzofuran-2(3H.)-one (3), denominated as parathesilactones A, B, C, respectively, and two new quinone derivatives, (2,7,8-trihydroxy-3,6-didecyldibenzo[b,d.]furan-1,4-dione (4) and (2,7,8-trihydroxy-3,6-dinonyldibenzo[b,d.]furan-1,4-dione) (5), denominated as parathesiquinones A, B, respectively, were isolated from the branches of Parathesis amplifolia. Lund. (Myrsinaceae). In addition, three known triterpenes, α.-amyrin (6), β.-amyrin (7), and bauerenol (8), and four known alkenylresorcinols, 5-pentadec-8-enyl resorcinol (9), 5-pentadec-10-enyl resorcinol (10), 5-heptadec-8-enyl resorcinol (11), and 5-heptadec-10-enyl resorcinol (12), were also isolated. The structure elucidation was achieved by means of MS, GC-MS, IR, ¹H, ¹³C spectroscopy including Heteronuclear Multiple Quantum Coherence (HMQC), and Heteronuclear Multiple Bond Correlation (HMBC) techniques.     

Antitumor effect of resorcinol derivatives from the roots of Ardisia brevicaulis by inducing apoptosis

Two new resorcinol derivatives 2-methoxy-4-hydroxy-6-(8Z-pentadecenyl)-benzene-1-O-acetate (1) and 2-methoxy-4-hydroxy-6-pentadecyl-benzene-1-O-acetate (2), together with four known compounds 2-methoxy-4-hydroxy-6-tridecyl-benzene-1-O-acetate (ardisiphenol D, 3), 5-(8Z-pentadecenyl)resorcinol (4), 5-pentadecylresorcinol (5), 5-tridecylresorcinol (6), have been isolated from the roots of Ardisia brevicaulis in our previous work. In the present study, the inhibitory effect of 1-6 on the proliferation of human pancreatic PANC-1, human lung A549, human gastrointestinal carcinoma SGC 7901, human breast MCF-7, and human prostate PC-3 cancer cells was evaluated by the methyl thiazolyl tetrazolium method. Compounds 1-6 all showed inhibitory activities against the proliferation of PANC-1, A549, SGC7901, MCF-7, and PC-3 cancer cells. Compound 3, the most active agent and the main constituent with the highest yield, induced apoptosis of PANC-1 cells (the most sensitive cell line among the cell lines screened) via the activation of caspase-3 and caspase-9, up-regulation of the ratio of bax/bcl-2 protein expression.     

Antitumor effect of resorcinol derivatives from the roots of Ardisia brevicaulis by inducing apoptosis

Two new resorcinol derivatives 2-methoxy-4-hydroxy-6-(8Z-pentadecenyl)-benzene-1-O-acetate (1) and 2-methoxy-4-hydroxy-6-pentadecyl-benzene-1-O-acetate (2), together with four known compounds 2-methoxy-4-hydroxy-6-tridecyl-benzene-1-O-acetate (ardisiphenol D, 3), 5-(8Z-pentadecenyl)resorcinol (4), 5-pentadecylresorcinol (5), 5-tridecylresorcinol (6), have been isolated from the roots of Ardisia brevicaulis in our previous work. In the present study, the inhibitory effect of 1–6 on the proliferation of human pancreatic PANC-1, human lung A549, human gastrointestinal carcinoma SGC 7901, human breast MCF-7, and human prostate PC-3 cancer cells was evaluated by the methyl thiazolyl tetrazolium method. Compounds 1–6 all showed inhibitory activities against the proliferation of PANC-1, A549, SGC7901, MCF-7, and PC-3 cancer cells. Compound 3, the most active agent and the main constituent with the highest yield, induced apoptosis of PANC-1 cells (the most sensitive cell line among the cell lines screened) via the activation of caspase-3 and caspase-9, up-regulation of the ratio of bax/bcl-2 protein expression.     

PTP1B inhibitors from Ardisia japonica

In bioassay-directed isolation from the whole plant of Ardisia japonica, sixteen known compounds: chrysophanol (1), physcion (2), oleanolic acid (3), euscaphic acid (4), tormentic acid (5), quercetin (6), quercitrin (7), myricitrin (8), kaempferol 3-O-alpha-L-rhamnopyranoside (9), cyclamiretin A 3-O-alpha--rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->4)]-alpha-L-arabinopyranoside (10), (7E)-9-hydroxymegastigma-4, 7-dien-3-on-9-O-beta-D-glucopyranoside (11), bergenin (12), norbergenin (13), rutin (14), kaempferol 3,7-O-alpha-L-dirhamnopyranoside (15), (-)-epigallacatechin 3-O-gallate (16) were obtained. Compounds 1-5, 9, 11 and 14-16 have not been reported previously from this plant. Among these isolates, 2, 3, 6 and 12 showed moderate bioactivity against PTP1B in vitro with IC50 values of 121.50, 23.90, 28.12 and 157 microM, respectively.     

Two new xanthones from the stems of Cratoxylum cochinchinense

Two new xanthones, 6-hydroxy-3,7-dimethoxy-8-(3-methylbut-2-enyl)-6′,6′-dimethyl-5′-hydroxy-4′,5′-dihydropyrano(2′,3′:1,2)xanthone (1) and 6-hydroxy-3,7-dimethoxy-8-(2-oxo-3-methylbut-3-enyl)-6′,6′-dimethyl-5′-hydroxy-4′,5′-dihydropyrano(2′,3′:1,2)xanthone (2), have been isolated from the stems of Cratoxylum cochinchinense (Lour.) Blume. Their structures were established on the basis of spectroscopic analysis.     

Two new compounds and anti-HIV active constituents from Illicium verum

Two new compounds named illiverin A (1) and tashironin A (8) were isolated from the roots of Illicium verum, together with seven known compounds: 4-allyl-2-(3-methylbut-2-enyl)-1,6-methylenedioxybenzene-3-ol (2), illicinole (3), 3-hydroxy-4,5-methylenedioxyallyl-benzene (4), (-)-illicinone-A (5), 4-allyl-4-(3-methylbut-2-enyl)-1,2-methylenedioxycyclohexa-2,6-dien-5-one (6), 3,4-seco-(24 Z)- cycloart-4(28),24-diene-3,26-dioic acid, 26-methyl ester (7) and tashironin (9). Based on 1D- and 2D-NMR data (COSY, HMQC, HMBC), the structures of the new compounds were deduced to be (E)-1-[(3-methylbut-2-enyl)oxy]-2-methoxy-4-(prop-1-enyl)benzene (1) and 11-O-debenzoyl-11alpha-O-2-methylcyclopent-1-enecarboxyltashironin (8). Compounds 1-9 were screened for anti-HIV activity in vitro whereby compounds 5 and 7 possessed moderate anti-HIV activity with EC50 values of 16.0 and 5.1 microM with SI values of 18.2 and 15.6, respectively.     

Two new aromatic compounds from the resin of Styrax tonkinensis (Pier.) Craib

Two new aromatic compounds, trans-(tetrahydro-2-(4-hydroxy-3-methoxyphenyl)-5-oxofuran-3-yl)methyl benzoate (1), 3-(4-hydroxy-3-methoxyphenyl)-2-oxopropyl benzoate (2) and one new natural product, 4-((E)-3-ethoxyprop-1-enyl)-2-methoxyphenol (3) together with five known aromatic compounds have been isolated from the resin of Styrax tonkinensis (Pier.) Craib. Their structures were determined by physical and spectroscopic methods.     

Bioassay‐Guided Isolation and Structural Modification of the Anti‐TB Resorcinols from Ardisia gigantifolia

Tuberculosis (TB) is a highly contagious disease mainly caused by Mycobacterium tuberculosis H₃₇R_V. Antitubercular (anti‐TB) bioassay‐guided isolation of the CHCl₃ extract of the leaves and stems of the medicinal plant Ardisia gigantifolia led to the isolation of two anti‐TB 5‐alkylresorcinols, 5‐(8Z‐heptadecenyl) resorcinol ( 1 ) and 5‐(8Z‐pentadecenyl) resorcinol ( 2 ). We further synthesized 15 derivatives based on these two natural products. These compounds (natural and synthetic) were evaluated for their anti‐TB activity against Mycobacterium tuberculosis H₃₇R_V. Resorcinols 1 and 2 exhibited anti‐TB activity with MIC values at 34.4 and 79.2 μm in MABA assay, respectively, and 91.7 and 168.3 μm in LORA assay, respectively. Among these derivatives, compound 8 was found to show improved anti‐TB activity than its synthetic precursor ( 2 ) with MIC values at 42.0 μm in MABA assay and 100.2 μm in LORA assay. The active compounds should be regarded as new hits for further study as a novel class of anti‐TB agents. The distinct structure–activity correlations of the parent compound were elucidated based on these derivatives.     

The Metabolism of [14C]Prenazone in the Rat

Abstract

1. [¹⁴C]Prenazone administered to rats (60 mg/kg) as a suspension by stomach tube was excreted to the extent of 43% dose in the urine in 24 h with only 3% in the faeces. After four days the cumulative excretion amounted to 52% in the urine and 15% in the faeces.

2. The two major urinary metabolites were trans-4-(3'-hydroxymethylbut-2'-enyl)-1,2-diphenylpyrazolidine-3, 5-dione (monohydroxyprenazone) and trans-4-(3'-hydroxymethylbut-2'-enyl)-1 -(p-hydroxyphenyl)-2-phenylpyrazolidine-3,5-dione- (dihydroxyprenazone). These did not appear to be conjugated.

3. Only very small amounts of unchanged prenazone were found in the urine.

4. The above monhydroxyprenazone and related compounds were synthesized.     

Specific anticancer activity of a new bisabolane sesquiterpene against human leukemia cells inducing differentiation in vitro

A bisabolane sesquiterpene, rel-(1S,4R,5S,6R)-4,5-diacetoxy-6- [(R)-5-hydroxy-1,5-dimethylhex-3-enyl]- 3-methylcyclohex-2-enyl (Z)-2-methylbut-2 -enoate, which was newly isolated from the roots of Leontopodium longifolium, presented specific anticancer activity against human leukemia HL-60 cells, but did not inhibit proliferation of human hepatoma SMMC-7721 cells and human normal hepatocytes L02 cells. Nitroblue tetrazolium (NBT) reduction, phagocytosis of latex beads, and cell electrophoresis all demonstrated that this bisabolane sesquiterpene presented its anticancer activity against human leukemia HL-60 cells in vitro via inducing cell differentiation. Our results may have implications for treatment of human leukemia with the sesquiterpene.     

Sabian, a novel flavonoid from Sabiayunnanensis

A novel flavonoid, [2-(3,4-dihydroxy-phenyl)-3,5,7-trihydroxy-4-oxo-4H-chromen-8-yl]-[8-hydroxy-7-(E-4-hydroxy-3-methyl-but-2-enyl)-2,2-dimethyl-chroman-5-yl]-acetic acid methyl ester (10), trivially named sabian, along with 11 known compounds, have been isolated from the stems and leaves of Sabia yunnanensis. Their structures were established on the basis of spectral analysis.     

Revised structures of epohelmins A and B isolated as lanosterol synthase inhibitors from a fungal strain FKI-0929

The structures of epohelmins A and B isolated as lanosterol synthase inhibitors from a fungal strain FKI-0929 were revised to be 1 alpha-hydroxy-3alpha-(4'-oxoundec-(5' E)-enyl)-pyrrolizidine and 1beta-hydroxy-3 alpha-(4'-oxoundec-(5 'E)-enyl)-pyrrolizidine, respectively, by comparison with spectral data of synthetic compounds.     

血党中两个新化合物的结构鉴定

为了系统研究广西草药血党的化学成分。本文采用多种色谱技术和光谱技术对血党根部进行了分离提取和结构鉴定。从石油醚提取部位分离得到两个新化合物, 经鉴定其结构分别为2-十三烷基-3-［(2-十三烷基-4-乙酰氧基-6-甲氧基)-苯氧基］-6-甲氧基-1,4-苯醌(1)和2-甲氧基-4-羟基-6-十三烷基-乙酸苯酯(2)。化合物1，2均为新化合物。     

Search for constituents with neurotrophic factor-potentiating activity from the medicinal plants of paraguay and Thailand

20 medicinal plants of Paraguay and 3 medicinal plants of Thailand were examined on nerve growth factor (NGF)-potentiating activities in PC12D cells. The trail results demonstrated that the methanol extracts of four plants, Verbena littoralis, Scoparia dulcis, Artemisia absinthium and Garcinia xanthochymus, markedly enhanced the neurite outgrowth induced by NGF from PC12D cells. Furthermore, utilizing the bioactivity-guided separation we successfully isolated 32, 4 and 5 constituents from V. littoralis, S. dulcis and G. xanthochymus, respectively, including nine iridoid and iridoid glucosides (1-9), two dihydrochalcone dimers (10 and 11), two flavonoids and three flavonoid glycosides (12-16), two sterols (17 and 18), ten triterpenoids (19-28), five xanthones (29-33), one naphthoquinone (34), one benzenepropanamide (35), four phenylethanoid glycosides (36-39) and two other compounds (40 and 41). Among which, 15 compounds (1-4, 10-11, 14-18, 29-31 and 34) were new natural products. The results of pharmacological trails verified that littoralisone (1), gelsemiol (5), 7a-hydroxysemperoside aglucone (6), verbenachalcone (10), littorachalcone (11), stigmast-5-ene 3beta,7alpha,22alpha-triol (18), ursolic acid (19), 3beta-hydroxyurs-11-en-28,13beta-olide (24), oleanolic acid (25), 2alpha,3beta-dihydroxyolean-12-en-28-oic acid (26), 1,4,5,6-tetrahydroxy-7,8-di(3-methylbut-2-enyl)xanthone (29), 1,2,6-trihydroxy-5-methoxy-7-(3-methylbut-2-enyl)xanthone (30), 1,3,5,6-tetrahydroxy-4,7,8-tri(3-methyl-2-butenyl)xanthone (31), 12b-hydroxy-des-D-garcigerrin A (32), garciniaxanthone E (33) and (4R)-4,9-dihydroxy-8-methoxy-alpha-lapachone (34) elicited marked enhancement of NGF-mediated neurite outgrowth in PC12D cells. These substances may contribute to the basic study and the medicinal development for the neurodegenerative disorder.     

Synthesis of (±)-methyl-(1 -aryl-4-pyridin-3-yl-but-3-enyl)-amines

trans-Metanicotine, a subtype (alpha4beta2)-selective ligand for neuronal nicotinic acetylcholine receptor, is under clinical phase for Alzheimer's disease. An efficient synthetic route for (+/-)-methyl-(1-aryl-4-pyridin-3-yl-but-3-enyl)-amines, derivatives of trans-metanicotine, was explored. Allylation reaction of aryl aldimines with allylmagnesium bromide in THF gave (+/-)-methyl-(1-aryl-but-3-enyl)-amines. Protection of the amines with the Boc group and following Heck reaction of the N-Boc amines with 3-bromopyridine gave (+/-)-methyl-(1-aryl-4-pyridin-3-yl-but-3-enyl)-carbamic acid tert-butyl esters. Deprotection of the N-Boc group in aqueous 1N-HCI solution gave the titled amines in good yields. Thus, trans-metanicotine analogues modified at the a-position of the methylamino group with aryl groups were obtained in 5 steps.     

Sabian,a novel flavonoid from Sabia yunnanensis

A novel flavonoid, [2-(3,4-dihydroxy-phenyl)-3,5,7-trihydroxy-4-oxo-4H-chromen-8-yl]-[8-hydroxy-7-(E-4-hydroxy-3-methyl-but-2-enyl)-2,2-dimethyl-chroman-5-yl]-acetic acid methyl ester (10), trivially named sabian, along with 11 known compounds, have been isolated from the stems and leaves of Sabia yunnanensis. Their structures were established on the basis of spectral analysis.     

Two new aromatic compounds from the resin of Styrax tonkinensis (Pier.) Craib

Two new aromatic compounds, trans-(tetrahydro-2-(4-hydroxy-3-methoxyphenyl)-5-oxofuran-3-yl)methyl benzoate (1), 3-(4-hydroxy-3-methoxyphenyl)-2-oxopropyl benzoate (2) and one new natural product, 4-((E)-3-ethoxyprop-1-enyl)-2-methoxyphenol (3) together with five known aromatic compounds have been isolated from the resin of Styrax tonkinensis (Pier.) Craib. Their structures were determined by physical and spectroscopic methods.