Oleanane-triterpene Saponins from Clinopodium urticifolium

Four new oleanane triterpene saponins were isolated and purified from the whole plant of Clinopodium urticifolium. They were 3β, 16β, 23, 28-tetrahydroxyoleana-9 (11), 12(13)-diene-3-yl-[β-D-glucopyranosyl-(1→2)]-[β-D-glucopyranosyl-(1→3)]- β-D-fucopyranoside 1; 3β, 16β,21β, 23, 28-pentahydroxyoleana-9(11), 12(13)-diene-3-yl-[β-D-glucopyranosyl-(1→2)]-[ β-D-glucopyranosyl-(1→3)]- β-D-fucopyranoside 2; 3β, 16β, 23, 28-tetrahydroxyoleana-9(11), 12(13)-diene-3-yl-[β-D-glucopyranosyl-(1→β)- β-D-glucopyranosyl-(1→3)]-[β-D-glucopyranosyl-(1→2)]-β-D-fucopyranoside 3; 3β, 16β, 23, 28-tetrahydroxyoleana-9(11), 12(13)-diene-3-yl-[β-D-gluco-pyranosyl-(1→4)-β-D-glucopyranosyl-(1→β)-β-D-glucopyranosyl-(1→3)]-[β-D-glucopyranosyl-(1→2)]- β-D-fucopyranoside 4. Their structures were elucidated on the basis of interpretation of NMR and MS data and from chemical evidence.     

Alkaloid and Anthraquinone Derivatives Produced by the Marine‐Derived Endophytic Fungus Eurotium rubrum

Cultivation of the fungal strain Eurotium rubrum, an endophytic fungus that was isolated from the inner tissue of the semi‐mangrove plant Hibiscus tiliaceus, resulted in the isolation of one new dioxopiperazine alkaloid, 12‐demethyl‐12‐oxo‐eurotechinulin B ( 1 ), and one new anthraquinone derivative, 9‐dehydroxyeurotinone ( 2 ), together with ten known compounds including variecolorin J ( 3 ), eurotechinulin B ( 4 ), variecolorin G ( 5 ), alkaloid E‐7 ( 6 ), cryptoechinuline G ( 7 ), isoechinulin B ( 8 ), 7‐isopentenylcryptoechinuline D ( 9 ), 2‐O‐methyl‐9‐dehydroxyeurotinone ( 10 ), emodin ( 11 ), and emodic acid ( 12 ). The structures of the isolated compounds were determined by extensive analysis of their spectroscopic data as well as by comparison with literature reports. Some of the purified compounds were evaluated for antibacterial, antifungal, and cytotoxic activities.     

维生素B12与12-钨磷酸相互作用的双波长共振瑞利散射光谱及其分析应用

建立了一种双波长共振瑞利散射光谱测定维生素B12的新方法. 在pH=1.0的HCl介质中, 维生素B12(VB12)与12-钨磷酸(TP)形成摩尔比为3:1的离子缔合物, 导致双波长共振瑞利散射(DWO-RRS)、 二级散射(SOS)和倍频散射(FDS)光谱显著增强, 其最大散射波长分别位于330和370 nm(RRS), 608 nm(SOS)和386 nm(FDS). 在一定范围内, 3种散射增强(ΔIRRS, ΔISOS和ΔIFDS)均与VB12的浓度成线性关系. 该方法具有较高的灵敏度, RRS, SOS和FDS法对VB12的检出限(3σ)在2.0~7.6 ng/mL之间. 研究了反应条件和共存物质的影响, 结果表明, 该方法具有良好的选择性. 据此, 提出了简便、 快速、 准确且高灵敏测定痕量VB12的光散射新方法, 适用于片剂和尿样中VB12的测定. 还对反应机理和散射光谱增强的原因进行了讨论.     

Degraded and oxetane-bearing limonoids from the roots of Melia azedarach

Brine shrimp lethality test (BST)-guided fractionation of a methanol extract of the roots of Melia azedarach resulted in the isolation of two new limonoids, 9alpha-hydroxy-12alpha-acetoxyfraxinellone (1) and 7,14-epoxy-azedarachin B (2), together with the known compounds, 12alpha-hydroxyfraxinellone (4), 9alpha-hydroxyfraxinellone (5), azedarachin B (6), and neoazedarachin B (7). The structures of 1 and 2 were elucidated by analysis of spectroscopic data and comparison of their NMR data with those of the known compounds. Compounds 1, 2 and 4-7 exhibited significant activity in the BST, in particular, azedarachin B (6) showed remarkable BST activity with an LC(50) value of 0.0098 microM.     

Simultaneous determination of vitamin B12 and its derivatives using some of multivariate calibration 1 (MVC1) techniques

Resolution of binary mixtures of vitamin B12, methylcobalamin and B12 coenzyme with minimum sample pre-treatment and without analyte separation has been successfully achieved by methods of partial least squares algorithm with one dependent variable (PLS1), orthogonal signal correction/partial least squares (OSC/PLS), principal component regression (PCR) and hybrid linear analysis (HLA). Data of analysis were obtained from UV-vis spectra. The UV-vis spectra of the vitamin B12, methylcobalamin and B12 coenzyme were recorded in the same spectral conditions. The method of central composite design was used in the ranges of 10-80mgL(-1) for vitamin B12 and methylcobalamin and 20-130mgL(-1) for B12 coenzyme. The models refinement procedure and validation were performed by cross-validation. The minimum root mean square error of prediction (RMSEP) was 2.26mgL(-1) for vitamin B12 with PLS1, 1.33mgL(-1) for methylcobalamin with OSC/PLS and 3.24mgL(-1) for B12 coenzyme with HLA techniques. Figures of merit such as selectivity, sensitivity, analytical sensitivity and LOD were determined for three compounds. The procedure was successfully applied to simultaneous determination of three compounds in synthetic mixtures and in a pharmaceutical formulation.     

Determination of a cationic surfactant with naphthalene black 12B by the resonance light scattering technique

A new determination method for a cationic surfactant, zephiramine (Zeph), was developed with resonance light scattering (RLS) technique, based on the interaction of naphthalene black 12B with Zeph. The resonance light scattering (RLS) and UV characteristics of interaction between naphthalene black 12B and Zeph were studied. The RLS intensity of naphthalene black 12B at 363 nm was greatly enhanced in the presence of Zeph at pH 6.0. The enhanced RLS is proportional to the concentration of Zeph in the range of 3.20 x 10(-7) - 1.44 x 10(-5) mol L(-1). The limit of detection was 8.8 x 10(-8) mol L(-1). The proposed method was applied to the determination of Zeph in synthetic and spiked water samples with the recovery of 96.2-104% and RSD of 1.1-2.5%.     

(Zr6B)Cl12(MeCN)6][Ph4B].1.6MeCN: an easily-accessible starting material for zirconium cluster chemistry and [(Zr6B)Cl12(Pyr6)][Ph4B].2{(PyrH)[Ph4B]}, a first reaction product

In an attempt to produce a convenient starting material for the development of new interstitially centered, octahedral zirconium cluster compounds by solution-chemical methods, a new approach, using Na[Ph4B] to withdraw all six outer chlorides by precipitating them as NaCl, was explored. From a solution of K 2[(Zr 6B)Cl15] and Na[Ph4B] in acetonitrile, the tetraphenylborate salt [(Zr6B)Cl12(MeCN)6][Ph4B].1.6 MeCN (1) was obtained with high yield. It contains the [(Zr6B)Cl(i)12(MeCN)(a)6](+) ion (2) with an octahedral metal core. The crystal structure of 1, which possesses high solubility in several organic solvents, is reported. Treatment of 1 with pyridine gave the new cluster phase [(Zr6B)Cl12(Pyr6][Ph4B].2{(PyrH)[Ph4B]} (3), which was characterized as well by X-ray crystallography. An advantage of both title phases is that they contain Lewis acidic zirconium cluster units, which might be useful as catalysts, with the additional advantage of tuneable redox properties.     

Bengamides revisited: new structures and antitumor studies

The structural chemistry and biological activity of the bengamide class of compounds have been further characterized. Extracts prepared from recollected Jaspis cf. coriacea from five sites in Fiji were pooled. Six new bengamides, M (7b), N (8a), O (8b), P (9a), Q (9b), and R (10), were identified, accompanied by the known bengamides A (1a), B (1b), E (3a), F (3b), Y (5), Z (6), L (7a), G (11a), H (11b), and I (12). The structures of the new compounds were determined from spectroscopic data, and some were additionally confirmed by semisynthesis. Cytotoxicity screening data were obtained from the NCI-DTP 60 cell screen for bengamides A, B, and P. Bengamides A and B were more potent than bengamide P, with average IC(50) values of 0.046, 0.011, and 2.70 FM, respectively. The in vitro antitumor activity against MDA-MB-435 human mammary carcinoma was also determined for natural bengamides A, B, E, F, P, M, O, and Z and for synthetic samples of B and O. The best activity was observed for the natural bengamides A (IC(50) = 1 nM) and O (IC(50) = 0.3 nM).     

New bisindole alkaloids isolated from Myxomycetes Arcyria cinerea and Lycogala epidendrum

Two new bisindole alkaloids, named cinereapyrrole A (1) and B (2), were isolated from wild fruit bodies of Arcyria cinerea and three new bisindole alkaloids (3-5) were isolated from wild fruit bodies of Lycogala epidendrum. Seven known bisindoles (6-12) were concomitantly obtained from them. The structures of the new compounds were elucidated by spectral data. Among these bisindole alkaloids, compound 12 showed cytotoxicity against cultured tumor cell lines.     

Polyoxygenated Cembranoids from Soft Coral Lobophytum Crassum and Their Anti-tumoral Activities

Four new cembranoids,6-oxo-cembrene-A (1),Iobocrassins G-H (2-3),and 14-epi-lobophytolide B (4),along with eight known related compounds (5-12),were isolated fr...     

New Tryptophan Metabolites from Cultures of the Lipophilic Yeast Malassezia furfur

Eleven new indole alkaloids were isolated from cultures of the human pathogenic yeast Malassezia furfur after addition of L ‐tryptophan as the sole N‐source: pityriacitrin B ( 2 ), the malassezindoles A ( 3 ) and B ( 4 ), malassezialactic acid ( 6 ), the malasseziazoles A ( 7 ), B ( 8 ), and C ( 9 ), pityriazole ( 10 ), malasseziacitrin ( 11 ), and malassezione ( 12 ), along with the known d‐ indole‐3‐lactic acid (=(αR)‐α‐hydroxy‐1H‐indole‐3‐propanoic acid 5 ), and 2‐hydroxy‐1‐(1H‐indol‐3‐yl)ethanone ( 13 ). The structural elucidation of these compounds was performed by spectroscopic methods (MS as well as 1D‐ and 2D‐NMR). The biogenetic relationships (Scheme) and biological activities of the new metabolites are discussed.     

Chemical constituents of the roots of Piper sarmentosum

Sixteen compounds were isolated from the fresh roots of Piper sarmentosum. Seven of these have been previously isolated from the fruits and leaves of this plant: the aromatic alkene (1), 1-allyl-2-methoxy-4,5-methylenedioxybenzene (4), beta-sitosterol, pyrrole amide (6), sarmentine (10), sarmentosine (13) and pellitorine (14). (+)-Sesamin (2), horsfieldin (3), two pyrrolidine amides 11 and 12, guineensine (15) and brachystamide B (16) are new for P. sarmentosum. Sarmentamide A, B, and C (7-9) are new natural products. Compounds 1--4 and 6--16 were tested for antiplasmodial, antimycobacterial and antifungal activities.     

Constituents of the Vietnamese medicinal plant Orthosiphon stamineus

From the MeOH extract of the aerial part of Vietnamese Orthosiphon stamineus, five new isopimarane-type diterpenes [orthosiphols F-J (1-5)] and two new diterpenes [staminols A (6) and B (7)] with a novel carbon-framework, to which we proposed the name "staminane", and three new highly-oxygenated staminane-type diterpenes [staminolactones A (8) and B (9) and norstaminol A (10)1 were isolated. Moreover, staminolactone A (8) is 8,14-secostaminane-type and staminolactone B (9) is 13,14-secostaminane-type, while norstaminol A (10) is 14-norstaminen-type. Together with these new diterpenes, sixteen known compounds were also isolated and identified to be: 7,3',4'-tri-O-methylluteolin (11), eupatorin (12), sinensetin (13), 5-hydroxy-6,7,3',4'-tetramethoxyflavone (14), salvigenin (15), ladanein (16), tetramethylscutellarein (17), 6-hydroxy-5,7,4'-trimethoxyflavone (18), vomifoliol (19), aurantiamide acetate (20), rosmarinic acid (21), caffeic acid (22), oleanolic acid (23), ursolic acid (24), betulinic acid (25), and beta-sitosterol (26). All the isolated compounds were tested for their cytotoxicity towards highly liver metastatic murine colon 26-L5 carcinoma cells, and the new diterpenes, except for 4, and flavonoids (11, 12, 16, 18) showed cytotoxicity with an ED50 value between 10 and 90 microg/ml.     

ent‐Kaurane Diterpenoids from Isodon phyllostachys

Phytochemical investigation of the medicinal plant Isodon phyllostachys led to the isolation of four new ent‐kaurane diterpenoids, phyllostacins F–I ( 1 – 4 , resp.), together with 11 known compounds, rosthorin A ( 5 ), rabdoternin C ( 6 ), enmenol ( 7 ), oridonin ( 8 ), lasiocarpanin ( 9 ), xerophilusin B ( 10 ), ponicidin ( 11 ), macrocalin B ( 12 ), phyllostachysin A ( 13 ), sculponeatin C ( 14 ), and macrocalyxoformin E ( 15 ). The structures of the new compounds were established by spectroscopic methods, including extensive 1D‐ and 2D‐NMR analyses. Compounds 1, 2, 7, 10 , and 13 were evaluated for their inhibitory activity against K562 and HepG2 cell lines.     

Flavonoid glycosides and other constituents of Psorospermum androsaemifolium BAKER (Clusiaceae)

Two new flavonoid glycosides, namely 3'-(2',4'-dihydroxybenzyloxy)acanthophorin B (1b) and beta,2,3',4,4',6-hexahydroxy-alpha-(alpha-L-rhamnopyranosyl)dihydrochalcone (2) were isolated from the leaves of Psorospermum androsaemifolium together with quercetin (1), acanthophorin B (1a), alpha- (3) and beta-amyrine (3a), vismiaquinone (4), 12-hentriacontanol and hentriacontane. The structures of these secondary metabolites were established using detailed spectroscopic analysis and by comparison with published data. Compounds 1, 1a, 1b, 2, 3, 3a and 4 showed weak antifungal and antibacterial activities.     

Three New Polyketide Metabolites from the Endophytic Fungal Strain Cladosporium tenuissimum LR463 of Maytenus hookeri

Three new polyketide metabolites, the twelve‐membered macrolides (6R,12S)‐6‐hydroxy‐12‐methyloxacyclodoecane‐2,5‐dione ( 1 ), (10S,12S)‐10‐hydroxy‐12‐methyloxacyclododecane‐2,5‐dione ( 2 ), and 4,5‐dihydroxy‐12‐methyloxacyclododecan‐2‐one ( 3 ), were isolated from the endophytic fungal strain Cladosporium tenuissimum LR463 of Maytenus hookeri, together with three known compounds, cladospolide A, cladospolide B, and isocladospolide B. Their structures were elucidated by spectroscopic analysis including 1D‐ and 2D‐NMR experiments, and the absolute configurations of 1 and 2 were determined by the Mosher ester method.     

The Relationship between Procyanidin Structure and Their Protective Effect in a Parkinson’s Disease Model

This study evaluated the effect of grape seed-derived monomer, dimeric, and trimeric procyanidins on rat pheochromocytoma cell line (PC12) cells and in a zebrafish Parkinson’s disease (PD) model. PC12 cells were cultured with grape seed-derived procyanidins or deprenyl for 24 h and then exposed to 1.5 mm 1-methyl-4-phenylpyridinium (MPP⁺) for 24 h. Zebrafish larvae (AB strain) 3 days post-fertilization were incubated with deprenyl or grape seed-derived procyanidins in 400 µM 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) for 4 days. The results showed that the procyanidin dimers procyanidin B1 (B1), procyanidin B2 (B2), procyanidin B3 (B3), procyanidin B4 (B4), procyanidin B1-3-O-gallate (B1-G), procyanidin B2-3-O-gallate (B2-G), and the procyanidin trimer procyanidin C1 (C1) had a protective effect on PC12 cells, decreasing the damaged dopaminergic neurons and motor impairment in zebrafish. In PC12 cells and the zebrafish PD model, procyanidin (B1, B2, B3, B4, B1-G, B2-G, C1) treatment decreased the content of reactive oxygen species (ROS) and malondialdehyde (MDA), increased the activity of antioxidant enzymes glutathione peroxidase (GSH-Px), catalase (CAT), and superoxide dismutase (SOD), and upregulated the expression of nuclear factor-erythroid 2-related factor (Nrf2), NAD(P)H: quinone oxidoreductase 1 (NQO1), and heme oxygenase-1 (HO-1). These results suggest that in PC12 cells and the zebrafish PD model, the neuroprotective effects of the procyanidins were positively correlated with their degree of polymerization.     

Triterpenoids and phenolics from the fruiting bodies of Inonotus hispidus and their activations of melanogenesis and tyrosinase

Two new 24-methyl lanostane triterpenoids,hispindic acids A and B(1 and 2),and a new phenolic compound,hispinine(7),along with nine known compounds(3-6,and 8-12),were isolated from the fruiting bodies of Inonotus hispidus.Their structures were elucidated based on the extensive analysis of spectroscopic data(NMR and HRMS).Hispindic acid A(1) possesses an unusual formyl group at C-30.Compounds 1,3-4,and 8 showed stronger activate abilities of melanogenesis and tyrosinase in B16 melanoma cells than those of positive control,8-methoxypsoralen,at 50 μmol/L     

Furanone Derivatives from Aspergillus sp. XW‐12, an Endophytic Fungus in Huperzia serrata

Two new 5‐methoxyfuran‐3(2H)‐one derivatives, huaspenone A ( 1 ) and B ( 2 ), together with four known ones, i.e., aspertetronin A ( 3 ), aspertetronin B ( 4 ), gregatin E ( 5 ), and penicilliol A ( 6 ), were isolated from the cultures of an endophytic fungus Aspergillus sp. XW‐12, derived from the stems of Huperzia serrata. The structures of the new isolates were established by detailed interpretation of the 1D‐ and 2D‐NMR and HR‐ESI‐MS data.     

Ent-kaurane diterpenoids from Isodon rubescens var. lushanensis

Four new ent-kaurane diterpenoids lushanrubescensins F-I (1-4), together with 11 known ones, lasiodonin (5), oridonin (6), ponicidin (7), isodonoiol (8), isodonal (9), rabdosin B (10), rabdoternins A and B (11 and 12), enmenol (13), epinodosin (14), and inflexusin (15), were isolated from Isodon rubescens var. lushanensis, and the structures were elucidated by spectroscopic analysis. The inhibitory effect against the K562, Bcap37, BGC823, BIU87, CA, CNE, and Hela cell lines of compounds 3 and 5-10 were evaluated.