Five new diterpenoids from Pseudolarix kaempferi

Five new diterpenoids, pseudolaric acids F (1), G (2), and H (3), 2',3'-dihydroxy-1'-propoxypseudolarate B (4), and 6'-O-acetylpseudolaric acid B O-beta-D-glucopyranoside (5), along with nine known diterpenoids, pseudolaric acids A, B, and C(1), deacetylpseudolaric acid C(2), deacetylpseudolaric acid A, methyl pseudolarate A, methyl pseudolarate B, pseudolaric acid A-O-beta-D-glucopyranoside, and pseudolaric acid B-O-beta-D-glucopyranoside, were isolated from the root bark of Pseudolarix kaempferi. Their structures and stereochemistry were elucidated mainly by spectral data, especially 2D NMR techniques.     

Pseudotrienic acids A and B, two bioactive metabolites from Pseudomonas sp. MF381-IODS

Bioassay-guided fractionation of the liquid culture broth of Pseudomonas sp. MF381-IODS yielded two new antimicrobial substances, identified as (2E,4E,6E)-9-[((2S,3R)-3-hydroxy-4-{[(3E,5E,7RS)-7-hydroxy-4-methylhexadeca-3,5-dienoyl]amino}-2-methylbutanoyl)amino]nona-2,4,6-trienoic acid and the tetradeca equivalent, named pseudotrienic acids A (1) and B (2), respectively. The compounds are prone to lactone formation, and their structures suggest them to be derived from ring opening of a macrolide. Pseudotrienic acids A and B inhibited growth of Staphylococcus aureus (MIC 70 microg/mL) and Pseudomonas syringae pv. syringae (MIC 70 microg/mL). Two known antimicrobial compounds, the polyketide 2,3-deepoxy-2,3-didehydrorhizoxin (3) and the tryptophan-derived pyrrolnitrin (4), were also identified.     

Lupeol long-chain fatty acid esters with antimalarial activity from Holarrhena floribunda

An ethnopharmacological investigation was conducted among the Baka pygmies of Dja biosphere reserve (Cameroon) to collect information on the antimalarial plants used in their daily life. Holarrhena floribunda is one of those plants. Extracts of the stem barks of H. floribunda showed remarkable inhibitory activity against drug-resistant strains of Plasmodium falciparum at doses of 1.02-18.53 microg/mL when tested in vitro against two parasite clones designated as Indochina (W-2) and Sierra Leone (D-6). The aqueous extract was the most active against Indochina (W-2), with IC50 values of 1.02 microg/mL, while the ethanolic extract appeared to be the most active against Sierra Leone (D-6), with an IC50 of 4.33 microg/mL. The bioassay-guided fractionation of the neutral fraction of the crude extract led to the isolation of lupeol (1) and its three new long-chain fatty acid ester derivatives, namely, 3-O-(3'-hydroxyeicosanoyl)lupeol (2), 3-O-[(2'-(tetracosyloxy)acetyl]lupeol (3), and 3-O-[(1' '-hydroxyoctadecyloxy)-2'-hydroxypropanoyl]lupeol (4). These new compounds displayed some in vitro inhibition activity against the chloroquine-resistant strain FCR-3 isolated from Gambia and the chloroquine-sensitive standard strain 3D7. The hydroxy group of the fatty acid side chain appears to decrease the observed activity.     

Antimycobacterial compounds from Piper sanctum

Bioassay-guided chromatographic separation of the antimycobacterial extract of the leaves of Piper sanctum afforded 14 new compounds, identified as 2-oxo-12-(3',4'-methylenedioxyphenyl)dodecane (1), 2-oxo-14-(3',4'-methylenedioxyphenyl)tetradecane (2), 2-oxo-16-(3',4'-methylenedioxyphenyl)hexadecane (3), 2-oxo-18-(3',4'-methylenedioxyphenyl)octadecane (4), 2-oxo-14-(3',4'-methylenedioxyphenyl)-trans-13-tetradecene (5), 2-oxo-16-(3',4'-methylenedioxyphenyl)-trans-15-hexadecene (6), 2-oxo-18-(3',4'-methylenedioxyphenyl)-trans-17-octadecene (7), 2-oxo-16-phenyl-trans-3-hexadecene (8), methyl [6-(10-phenyldecanyl)tetrahydropyran-2-yl]acetate (9), methyl 2-(6-tridecyltetrahydro-2H-pyran-2-yl)acetate (10), methyl 2-(5-tetradecyltetrahydro-2-furanyl)acetate (11), 2-oxo-14-(3',4'-methylenedioxyphenyl)-trans-3-tetradecene (12), 2-oxo-16-(3',4'-methylenedioxyphenyl)-trans-3-hexadecene (13), and 2-oxo-16-phenyl-3-hexadecane (14). In addition, p-eugenol (15), methyleugenol (16), Z-piperolide (17), demethoxyyangonin (18), 5,6-dehydro-7,8-dihydromethysticin (19), cepharanone B (20), piperolactam A (21), cepharadione B (22), N-trans-feruloyltyramine (23), and N-trans-(p-coumaroyl)tyramine (24) were obtained from the anti-TBC stem extract of the plant. GC-MS and HPLC analyses of the essential oils of the leaves and stem revealed that safrol (25) was the major component of the oils. Compounds 2, 3, 6, 18-21, and 24 inhibited the growth of Mycobacterium tuberculosis when tested by the MABA assay, with MIC values ranging from 4 to 64 microg/mL.     

Phenolic compounds from Nymphaea odorata

Assay-guided fractionation of the ethanol extract of Nymphaea odorata resulted in the identification of two lignans, one new (1) and one known (2), together with six known flavonol glycosides (3-8). The structures of 1-8 were established by spectroscopic analysis as nymphaeoside A (1), icariside E(4) (2), kaempferol 3-O-alpha-l-rhamnopyranoside (afzelin, 3), quercetin 3-O-alpha-l-rhamnopyranoside (4), myricetin 3-O-alpha-l-rhamnopyranoside (myricitrin, 5), quercetin 3-O-(6' '-O-acetyl)-beta-d-galactopyranoside (6), myricetin 3-O-beta-d-galactopyranoside (7), and myricetin 3-O-(6' '-O-acetyl)-beta-d-galactopyranoside (8). Compounds 3, 4, and 7 showed marginal inhibitory effect against fatty acid synthase with IC(50) values of 45, 50, and 25 microg/mL, respectively.     

Antifungal activity of Heterothalamus alienus metabolites

The chemical study of Heterothalamus alienus gave rutin, spathulenol (1), (1R,7S)-germacra-4(15),5,10(14)-trien-1beta-ol (2), sakuranetin (3), padmatin 3-acetate (4), (2R,3R)-dihydroquercetin-7,3',4'-trimethyl ether (5), (2R,3R)-dihydroquercetin-7,4'-dimethyl ether (6), (2R,3R)-3-acetoxy-5,7,4'-trihydroxyflavanone (7), as the main components of an antifungal extract of the aerial parts of the plant. Compound 2 showed moderate activity, with Epidermophyton floccosum being the most susceptible species (MIC = 100 microg/mL); compound 3 showed the best antifungal behavior having a broad spectrum of action and the lowest MICs. This flavanone along with flavanolol 5 showed very good activity against standardized (MIC = 31.2 microg/mL) as well as clinical isolates of Trichophyton rubrum and T. mentagrophytes (MIC ranges 31.2-62.5 microg/mL and 31.2-125 microg/mL, respectively) and demonstrated not only fungistatic but also fungicide properties. Flavanolol 6 was active against all the dermatophytes tested with MICs of 62.5-250 microg/mL. Rutin, spathulenol (1) and the 3-acetylated flavanones 4 and 7 were inactive or marginally active against the fungal panel.     

Activity-guided isolation of constituents of Renealmia nicolaioides with the potential to induce the phase II enzyme quinone reductase

Three new prenylated dihydrochalcones, (+/-)-nicolaioidesins A, B, and C (1-3), as well as a new natural product, 5-styrylfuran-2-carboxylic acid methyl ester (4), along with four known compounds, 2'-hydroxy-4',6'-dimethoxychalcone (5), (+/-)-5-hydroxy-7-methoxyflavanone (6), (+/-)-5-hydroxy-7,4'-dimethoxyflavanone, and panduratin A, were isolated from the roots of Renealmia nicolaioides, using a bioassay to determine the induction of quinone reductase (QR) activity with cultured Hepa lclc7 mouse hepatoma cells. Among these isolates, 5 and 6 induced QR activity, with observed concentrations to double activity (CD) values of 1.7 and 0.9 microg/mL, respectively, while the other constituents were not regarded as being active (CD >10 microg/mL). The chemical structures of 1-4 were elucidated by spectroscopic methods. A biogenetic pathway for the formation of (+/-)-nicolaioidins A-C (1-3) is proposed.     

Activity-guided isolation of antioxidative constituents of Cotinus coggygria

Six constituents (1-6) were isolated from EtOAc-soluble partitions of two separate collections of the whole plants of Cotinus coggygria, namely, disulfuretin ?2,2'-[1,2-bis(3,4-dihydroxyphenyl)-1, 2-ethanedylidene]bis[6-hydroxy-3(2H)-benzofuranone] (1)?, sulfuretin (2), sulfurein (3), gallic acid (4), methyl gallate (5), and pentagalloyl glucose (6). The structure of the novel biaurone 1 was determined by spectral and chemical methods. Compounds 1-6 were found to be potent antioxidants in a 1,1-diphenyl-2-picrylhydrazyl free-radical scavenging assay.     

Natural products inhibiting Candida albicans secreted aspartic proteases from Lycopodium cernuum

Activity-guided fractionation of an ethanol extract of Lycopodium cernuum for Candida albicans secreted aspartic proteases (SAP) inhibition resulted in the identification of six new (1-6) and four known (7-10) serratene triterpenes, along with the known apigenin-4'-O-(2' ',6' '-di-O-p-coumaroyl)-beta-D-glucopyranoside (11). On the basis of spectroscopic analysis, the structures of 1-10 were established as 3beta,14alpha,15alpha,21beta,29-pentahydroxyserratane-24-oic acid (lycernuic acid C, 1), 3beta,14alpha,15alpha,21beta-tetrahydroxyserratane-24-oic acid (lycernuic acid D, 2), 3beta,14beta,21beta-trihydroxyserratane-24-oic acid (lycernuic acid E, 3), 3beta,21beta,29-trihydroxy-16-oxoserrat-14-en-24-methyl ester (lycernuic ketone A, 4), 3alpha,21beta,29-trihydroxy-16-oxoserrat-14-en-24-methyl ester (lycernuic ketone B, 5), 3alpha,21beta,24-trihydroxyserrat-14-en-16-one (lycernuic ketone C, 6), 3beta,21beta-dihydroxyserrat-14-en-24-oic acid (lycernuic acid A, 7), 3beta,21beta,29-trihydroxyserrat-14-en-24-oic acid (lycernuic acid B, 8), serrat-14-en-3beta,21beta-diol (9), and serrat-14-en-3beta,21alpha-diol (10). The 13C NMR data for the known compounds 7 and 8 are reported for the first time. Compounds 1 and 11 showed inhibitory effects against C. albicans secreted aspartic proteases (SAP) with IC50 of 20 and 8.5 microg/mL, respectively, while the other compounds were inactive.     

ent-rosane and labdane diterpenoids from Sagittaria sagittifolia and their antibacterial activity against three oral pathogens

Seven new ent-rosane diterpenoids, sagittines A-G (1-7), together with one new labdane diterpene, 13-epi-manoyl oxide-19-O-alpha-l-2',5'-diacetoxyarabinofuranoside (8), were isolated from the whole plant of Sagittaria sagittifolia. The structures and relative configurations of 1-8 were characterized using spectroscopic means, chemical methods, and X-ray crystallography. Compounds 1-4 exhibited antibacterial activity against the oral pathogens Streptococcus mutans ATCC 25175 and Actinomyces naeslundiis ATCC 12104, with MIC values between 62.5 and 125 microg/mL. Compound 5 was active against only A. naeslundiis ATCC 12104, with an MIC value of 62.5 microg/mL.     

New bioactive prenylflavonoids and dibenzocycloheptene derivative from roots of Dendrolobium lanceolatum

Two new flavanones (1 and 2), a new flavan (3), and a new rare dibenzocycloheptene derivative (4) together with a known flavan, 4'-hydroxy-2' ',2' 'dimethyl-pyranoflavan (5), were isolated from the roots of Dendrolobium lanceolatum. Their structures were established on the basis of spectral evidence, and an X-ray analysis was performed to confirm the structure of 4. Compounds 1-3 exhibited antimalarial activity with IC50 values of 2.6, 3.3, and 3.1 microg/mL, respectively. Compounds 1-5 showed moderate antimycobacterial activity with MIC values of 6.3, 12.5, 25, 25, and 50 microg/mL, respectively. In addition, 1 showed strong cytotoxicity against cancer cell lines KB, BC, and NCI-H187 with IC50 values of 1.2, 1.6, and 0.6 microg/mL, respectively, while 2 showed moderate cytotoxicity against the NCI-H187 cell line with an IC50 value of 8.1 microg/ mL.     

Isolation and structure elucidation of an isoflavone and a sesterterpenoic acid from Henriettella fascicularis

A new isoflavone, 4',5,7-trihydroxy-6,8-dimethylisoflavone (1), and a new sesterterpenoic acid (2), together with five known compounds, lichexanthone (3), (-)-pinoresinol (4), betulinic acid, palmitic acid, and beta-sitosterol, were isolated from a dichloromethane extract of the branches of Henriettella fascicularis. Their structures were established by extensive spectroscopic methods. An attempt to determine the absolute stereochemistry of (2E,6S)-6-[(1R,5Z,3aS,9R,10Z,12aR)-1,2,3,3a,4,7,8,9,12,12a-decahydro-9-hydroxy-3a,6,10-trimethylcyclopentanocycloundecen-1-yl]-2-methylhept-2-enoic acid (2) was performed by single-crystal X-ray analysis, using Cu Kalpha radiation. Compound 1 showed significant competitive binding to estrogen receptor beta and moderate antiestrogenic activity with cultured Ishikawa cells.     

Antimalarial, cytotoxic, and antifungal alkaloids from Duguetia hadrantha

Bioassay-guided isolation of Duguetia hadrantha yielded two new 4,5-dioxo-1-azaaporphinoids, hadranthine A (1) and hadranthine B (2), together with the known alkaloids imbiline-1 (3), sampangine (4), and 3-methoxysampangine (5), whose structures were determined primarily from 2D-NMR 1H-13C HMBC, and 1H-15N HMBC experiments. This is the first report of the co-occurrence of the copyrine alkaloids 4 and 5, as well as the first report of either copyrine or imbiline type alkaloids from a Duguetia species. Compounds 1, 4, and 5 demonstrated in vitro antimalarial activity against Plasmodium falciparum (W-2 clone), while 2 was inactive. Instead, 2 showed in vitro cytotoxicity to selected human cancer cell lines (IC50 = 3-6 microg/mL against SK-MEL, KB, BT-549, and SK-OV-3), and 4 was also cytotoxic to human malignant melanoma (IC50 = 0.37 microg/mL). Sampangine (4) also inhibited cell aggregation with a MIC value of <0.15 microg/mL, while 3-methoxysampangine (5) was only weakly active.     

Bioactive polyketides from Peperomia duclouxii

Four new compounds (1-4) were isolated along with 16 known compounds from whole plants of Peperomia duclouxii. The new structures were elucidated as 4-hydroxy-2-[(3,4-methylenedioxyphenyl)nonanoyl]cyclohexane-1,3-dione (1), 4-hydroxy-2-[(3,4-methylenedioxyphenyl)undecanoyl]cyclohexane-1,3-dione (2), 4-hydroxy-2-[(3,4-methylenedioxyphenyl)tridecanoyl]cyclohexane-1,3-dione (3), and 2-[(3,4-methylenedioxyphenyl)dodecyl]-4-hydroxy-2,3,4,6,7,8-hexahydro-2H-1-benzopyran-5-one (4), by analysis of their spectroscopic data. The known polyketides, surinone A and oleiferinone, showed cell growth inhibitory activity against the WI-38, VA-13, and HepG2 cell lines with IC50 values that ranged from 4.4 to 9.6 microg/mL. The known sesquiterpenoid, sinugibberodiol, showed a more potent effect on calcein accumulation than verapamil at 2.5 and 25 microg/mL. Compounds 3 and 4, surinone A, and oleiferinone showed moderate to weak inhibitory activity on the induction of the intercellular adhesion molecule-1 (ICAM-1) in the presence of IL-1alpha or TNF-alpha.     

Anti-TB polyynes from the roots of Angelica sinensis

Following chemotaxonomic evidence, the PE and CHCl(3) extracts of the roots of the botanical Angelica sinensis (Oliv.) Diels (Dang Gui) were investigated for in vitro anti-TB activity, in parallel to studying their serotonergic and GABAergic potential. The activities were confirmed to overlap chemically with the neurotropic active principles present in medium lipophilic fractions. Phytochemical investigations led to the isolation of five polyynes: falcarindiol (1), 9Z,17-octadecadiene-12,14-diyne-1,11,16-triol,1-acetate (2), oplopandiol (3), heptadeca-1-ene-9,10-epoxy-4,6-diyne-3,8-diol (4) and the new polyyne 8-hydroxy-1-methoxy-(Z)-9-heptadecene-4,6-diyn-3-one (5), as characterized by spectroscopic techniques including 1D, 2D NMR and HR-MS. All compounds were tested against two pathogenic strains of Mycobacterium tuberculosis (H37Rv and Erdman) in vitro in a microplate Alamar Blue assay (MABA). The most potent anti-TB constituents were 1 and 2, exhibiting MIC values of 1.4-26.7 microg/mL; 3 showed moderate MICs (49.5 and 50.2 microg/mL, respectively) while 4 and 5 were weakly active (MIC > 60 microg/mL). Notably, none of the five compounds exhibited significant cytotoxicity against Vero cells. These findings not only reveal a new potential area of therapeutic value for A. sinensis, but also underline the role of polyynes as anti-TB active principles in ethnobotanical preparations, and as lead compounds.     

Mycobacterium tuberculosis growth inhibition by constituents of Sapium haematospermum

Four novel compounds consisting of two new pimaranes, lecheronol A (1) and lecheronol B (2), an acylated cycloartane, 3-O-beta-lauroyl-cycloart-(23E)-en-25-ol (10), and a highly oxygenated novel chalconoid, alpha,beta,3,4,5,2',4',6'-octahydroxydihydrochalcone (12), were isolated along with seven known triterpene derivatives and three flavonol glucosides from Mycobacterium tuberculosis growth-inhibiting fractions of the CH(2)Cl(2)/MeOH (1:1) extract of the aerial parts of Sapium haematospermum. Compounds 1, 3 (3 alpha-hydroxyolean-12-ene), 8 [3 alpha-hydroxylup-20(29)-en], and 9 (cycloartanol) were found most active, with MIC values of 4, 12.2, 13.4, and 8 microg/mL, respectively. Cytotoxicity tests in Vero cells for compounds 1, 3, 8, and 9 gave IC(50) values of 104.8, 127.2, 127.2, and 102.4 microg/mL, respectively.     

蝉翼藤根茎化学成分研究

目的:研究蝉翼藤根茎氯仿部分化学成分。方法:采用各种色谱法分离,运用多种波谱技术鉴定结构,并对部分化合物进行了体外DPPH抗氧化试验。结果:分离鉴定出7个化合物,经鉴定为:3,4-二羟基苯甲酸(1),3-羟基-4-甲氧基苯甲酸(2),4-羟基-3-甲氧基-1-烯丙醛基苯(3),7-羟基-1,2,3,8-四甲氧基酮(4),1,3,8-三羟基-4-甲氧基酮(5),1,3,8-三羟基-2-甲氧基酮(6),1,3,6-三羟基-2,7-二甲氧基酮(7)。结论:化合物1～6为首次从该属中得到,化合物3表现出良好的抗氧化能力IC₅₀=4.14μg·mL^-1。     

轮叶棘豆的化学成分研究

目的：研究轮叶棘豆的化学成分。方法：90%乙醇冷浸提取,所得浸膏经硅胶,聚酰胺,C-18,Sephadex LH-20等多种材料进行柱色谱分离,通过波谱学方法鉴定化合物的结构。结果：分离鉴定了8个化合物,分别鉴定为azukisapogenol(1),(22E,24R)-24-甲基-5α-胆甾-7,22-二烯-3β,5α,6β-三醇(2),芹菜素(3),3′,4′-二甲氧基-槲皮素-3-O-β-D-半乳糖吡喃苷 (4),7,4′- 二甲氧基-槲皮素-3-O-α-L-鼠李糖吡喃基(1→2)-β-D-葡萄糖吡喃苷(5),(2S,3S,4R)-N-［(R)-2′-羟基二十四烷醇基］-1,3,4-三羟基-2-氨基-十八-6-烯(6),β-谷甾醇(7),胡萝卜苷(8)。结论：所有化合物均为首次从该植物中分得。     

Antitubercular chromones and flavonoids from Pisonia aculeata

Three new chromones, pisonins A (1), B (2), and D (4), two new flavonoids, pisonivanone [(2S)-5,7,2'-trihydroxy-8-methylflavanone] (7) and pisonivanol [(2R,3R)-3,7-dihydroxy-5,6-dimethoxyflavanone] (8), one new isoflavonoid, pisonianone (5,7,2'-trihydroxy-6-methoxy-8-methylisoflavone) (9), and five compounds first isolated from nature, namely, pisonins C (3), E (5), and F (6), pisoniamide (10), and pisonolic acid (11), together with 18 known compounds have been isolated from the methanol extract of the combined stem and root of Pisonia aculeata. Among these isolates, 2, 7, 14, 16, and 19 exhibited antitubercular activities (MICs≤50.0 μg/mL) against Mycobacterium tuberculosis H37Rv in vitro.     

Antidermatophytic properties of extracts from the leaves of Aristolochia paucinervis Pomel

Several fractions of a methanol extract from the leaves of Aristolochia paucinervis Pomel (Aristolochiaceae) were screened for their antidermatophytic efficiency against different human pathogenic fungi responsible for tinea and other skin infections. The antifungal study was carried out by the macrodilution agar method and the results showed that, with the exception of the aqueous fraction, all the fractions exhibited antifungal activities against the dermatophytic fungi tested. The hexane fraction was found to be the most effective (MIC range: 64-2048 microg/mL), whereas the butanol fraction was the least active (MIC range: 1024 microg/mL to more than 2048 microg/mL). The most susceptible fungi were Epidermophyton floccosum and Trichophyton violaceum in contrast to Trichophyton mentagrophytes and Trychophyton rubrum which were less sensitive to the fractions tested. The effects were compared with those of ketoconazole, amphotericin B and griseofulvin, for which MIC ranges were, respectively, 0.12-4 microg/mL, 0.5-4 microg/mL and 0.5-2 microg/mL.