New triterpenoids from the leaves of Cyclocarya paliurus

Six new triterpenoids including four new secodammarane triterpenoid glycosides (1-4), an epoxydammarane triterpenoid glycoside (5), and a new secodammarane triterpenoid (6) were isolated from the ethanolic extract of the leaves of Cyclocarya paliurus. The structures of these compounds were elucidated by spectroscopic analysis methods. Compounds 1-6 were evaluated for their inhibitory activities against α-glucosidase, lipase, DPP-IV, and aldose reductase.     

New tetralone derivatives from the leaves of Cyclocarya paliurus

Two new tetralone derivatives, named cyclopalosides A (1) and B (2), were isolated from the leaves of Cyclocarya paliurus by column chromatography on silica gel, reversed-phase C₁₈ silica gel and preparative HPLC. Their chemical structures were established on the basis of extensive analyses of spectroscopic data. Their structural characteristic is tetralone glycoside with a caffeoyl unit. The antioxidant activities of compound 1 were evaluated by using hydroxyl, superoxide anion, and DPPH radical scavenging assay.     

New dammarane triterpenoid saponins from the leaves of Cyclocarya paliurus

Abstract

Three new dammarane triterpenoid saponins, cyclocariosides O-Q (1–3), were isolated from the ethanolic extracts of the leaves of Cyclocarya paliurus. The structures of these compounds were elucidated by spectroscopic methods.     

Geraniinic acid derivative from the leaves of Phyllanthus reticulatus

Chemical constituents as well as cytotoxic and insecticidal activity of the crude methanol extract from the leaves of Phyllanthus reticulatus Poir. (Euphorbiaceae) were investigated. (5R*,6R*)-4,6-Dimethoxycarbonyl-5-[2′,3′,4′-trihydroxy-6′-(methoxycarbonyl) phenyl]-5,6-dihydro-2H-pyran-2-one (1) along with 3,4,3′-tri-O-methylellagic acid, and methyl gallate were isolated from the dichloromethane extract. Determination of their structures was based on spectroscopic analysis. Compound 1 possessed a very weak insecticidal activity against Spodoptera frugiperda (Sf9) with an IC₅₀ value of 27.27?μg/mL.     

Pharmacokinetics, tissue distribution and placental permeability of tetrahydro-tetramethyl-naphthalenyl-propenyl benzoic acid (a retinoidal benzoic acid derivative) in hamsters

Tritiated tetrahydro-tetramethyl-naphthalenyl-propenyl benzoic acid (TTNPB; Ro 13-7410) was administered as a single oral bolus to pregnant hamsters (day 8) to determine the maternal plasma pharmacokinetic profile and peripheral tissue distribution patterns. Blood and tissue, including embryo or fetus, were collected at specific time intervals to 96 h and assayed for total radioactive compounds and/or parent retinoid. No lag time was required to describe retinoid absorption (t 1/2 pi = 1.2 h) with peak plasma levels at 2.4 h; the concentrations then declined with exponential elimination from the central compartment (t 1/2 e = 3 h). The maximum concentrations of circulating radioactive compound or metabolites after 100 micrograms/kg [3H]2-TTNPB occurred in liver greater than fetus greater than adrenal greater than lung approximately equal to kidney greater than plasma; after 1000 micrograms/kg, maternal liver accumulated the highest concentration followed by plasma greater than fetus = placenta = uterus. An unidentified, polar metabolite was detected in plasma at 0.5 h and by 12 h constituted greater than 90% of the total circulating radioactivity. TTNPB was absorbed and cleared more slowly, concentrated in the conceptus to a higher degree and possessed greater intrinsic activity than the naturally-occurring tetraene retinoids. These properties contribute to the marked teratogenic activity of TTNPB as compared to the tetraene retinoids.     

A new ascorbic acid derivative and two new terpenoids from the leaves and twigs of Rhododendron decorum

The phytochemical study of the ethanol extract of the leaves and twigs of Rhododendron decorum afforded a new ascorbic acid derivative (1), a new ionone analogue (2), a new ursane-type triterpenoid glucoside (3), and four known compounds (4?7). The structures were elucidated by spectroscopic analyses, including HRESIMS, 1D, and 2D NMR. The anti-neuroinflammatory activities of the compounds were evaluated by measuring inhibitory effects of LPS-induced NO production in BV2 cells.     

A new benzoquinone derivative from the leaves of Garcinia parvifolia

Parvifoliquinone (1) was isolated from the leaves of Garcinia parvifolia together with six known compounds: parvifoliols B (2), C (3), E (4), garcidepsidone B (5), nigrolineaisoflavone A (6), and mangostinone (7). The structures were elucidated by spectral analyses. Their antibacterial activity against methicillin-resistant Staphylococcus aureus was evaluated.     

A new ionone derivative from the leaves of Picrasma quassioides

Nigakialcohol A (1), as unusual cyclization ionone derivative, together with eight known ones (2–9), were isolated from the leaves of Picrasma quassioides (D. Don) Benn (Simaroubaceae). Their structures were elucidated by extensive spectroscopic analyses and comparison with literature data. Compound 2 showed a weak inhibitory effect on NO production at non-cytotoxic concentration (100 μM) with inhibitory rate of 59%, and thus it should be regarded as potential anti-inflammatory agents.     

A novel analgesic pyrazine derivative from the leaves of Croton tiglium L

A novel analgesic pyrazine derivative, named crotonine, was isolated from the leaves of Croton tiglium L. The structure was elucidated as 2-(furan-2-yl)-5-(2,3,4-trihydroxy-butyl)-1,4-diazine by spectroscopic analysis. Crotonine inhibited remarkably the acetic acid-induced writhing in mice.     

Kakispyrol, a new biphenyl derivative from the leaves of Diospyros kaki

A new biphenyl derivative, 4',5-dimethoxy-3-beta-D-glucopyranosyloxy-4-hydroxy-biphenyl, named kakispyrol (1), has been isolated from the leaves of Diospyros kaki, together with three known compounds, vitexin (2), 2'-O-rhamnosyl vitexin (3) and isorhamnetin-3-O-beta-D-glucopyranoside (4). The structure of compound 1 has been determined on the basis of spectroscopic evidence.     

Highly potent and stereoselective effects of the benzoic acid derivative AZ-DF 265 on pancreatic beta-cells.

1. Mouse islets were used to define the characteristics and study the mechanisms of the stimulation of insulin release by compound AZ-DF 265, 4-[[N-(alpha-phenyl-2-piperidino-benzyl) carbamoyl]methyl] benzoic acid, a substituted benzoic acid with an asymmetric carbon atom. 2. At a non-stimulatory concentration of glucose (3 mM), (-)-AZ-DF 265 reversibly inhibited 86Rb efflux from islet cells, depolarized the beta-cell membrane, induced electrical activity, stimulated 45Ca efflux, and triggered insulin release. Maximum inhibition of 86Rb efflux occurred at 0.03 microM (-)-AZ-DF 265, whereas the threshold concentration for stimulation of release was 0.1 microM. Omission of extracellular Ca2+ abolished all effects of the drug but the inhibition of 86Rb efflux. 3. At a stimulatory concentration of glucose (10 mM), (-)-AZ-DF 265 reversibly increased 86Rb efflux, potentiated electrical activity, augmented 45Ca efflux, and increased insulin release. Maximum stimulation of 86Rb efflux and insulin release was obtained with 0.03 microM (-)-AZ-DF 265. Omission of extracellular Ca2+ abolished all effects of the drug. 4. The potency of (-)-AZ-DF 265 was similar to that of glibenclamide, whereas the (+)-enantiomer was about 10 times less potent on 86Rb efflux and insulin release. 5. It is concluded that, like sulphonylureas, compound AZ-DF 265 decreases K+ permeability of the beta-cell membrane and thereby causes depolarization. This activates voltage-dependent Ca channels, permits Ca2+ influx and eventually stimulates insulin release. Its stereoselectivity may help to elucidate the mechanisms of K channel blockade and, hence, lead to the design of more potent and specific insulinotropic drugs.     

A novel analgesic pyrazine derivative from the leaves of Croton tiglium L.

A novel analgesic pyrazine derivative, named crotonine, was isolated from the leaves of Croton tiglium L. The structure was elucidated as 2-(furan-2-yl)-5-(2,3,4-trihydroxy-butyl)-1,4-diazine by spectroscopic analysis. Crotonine inhibited remarkably the acetic acid-induced writhing in mice.     

Synthesis and biological activities of the tri-L-alanine derivative of isonicotinic acid hydrazide

N-(tert-Butyloxycarbonyl) tri-L-alanine was coupled to the hydrazide function of isonicotinic acid hydrazide followed by cleavage of the amino protective group. The resulting dihydrochloride of the tri-L-alanine derivative of isonicotinic acid hydrazide was characterized by 13C-NMR. The minimal inhibitory concentration of isonicotinic acid hydrazide was not improved by the peptide derivative, and competition experiments with tri-L-alanine demonstrated that tri-L-alanyl-isonicotinic acid hydrazide did not use the peptide transport system. Isonicotinic acid hydrazide and its tri-peptide derivative possessed the same activity against pathogenic mycobacteria and did not antagonize each other. The relatively high stability of the tri-peptide derivative against peptidases of Mycobacterium fortuitum was discussed as being responsible for the significantly weaker activity against this atypical mycobacterium strain. With the exception of peptidases of hog intestinal mucose, the tri-L-alanyl derivative of isonicotinic acid hydrazide was stable to pronase and alpha-chymotrypsin when compared to other peptides.     

A novel analgesic pyrazine derivative from the leaves of Croton tiglium L.

A novel analgesic pyrazine derivative, named crotonine, was isolated from the leaves of Croton tiglium L. The structure was elucidated as 2-(furan-2-yl)-5-(2,3,4-trihydroxy-butyl)-1,4-diazine by spectroscopic analysis. Crotonine inhibited remarkably the acetic acid-induced writhing in mice.     

A new sesquiterpene lactone glycoside and a new quinic acid methyl ester from Patrinia villosa

A new sesquiterpene lactone glycoside (1) and a new quinic acid methyl ester (2) were isolated from Patrinia villosa, together with another two known compounds chlorogenic acid n-butyl ester (3), 3, 4-di-O-caffeoylquinic acid methyl ester (4). Their structures were established using 1D/2D-NMR spectroscopy, mass spectrometry, and comparing with spectroscopic data reported in the literature.     

FR258900, a novel glycogen phosphorylase inhibitor isolated from Fungus No. 138354. I. Taxonomy, fermentation, isolation and biological activities

FR258900 is a novel glycogen synthesis activator produced by Fungus No. 138354. This compound was isolated from the culture broth by solvent extraction and reverse-phase column chromatography. FR258900 stimulated glycogen synthesis and glycogen synthase activity in primary rat hepatocytes. FR258900 exhibited a potent inhibitory effect on the activity of liver glycogen phosphorylase, suggesting that this compound may activate hepatic glycogen synthesis via glycogen phosphorylase inhibition. Thus, this glycogen phosphorylase inhibitor may be useful in the treatment of postprandial hyperglycemia in type 2 diabetes.     

Ardisiatetrons A and B: tetronic acid derivatives and triterpenes from the leaves of Ardisia quinquegona and their biological activity

Journal of Natural Medicines - From the leaves of Ardisia quinquegona, two alkylated tetronic acid derivatives, named ardisiatetrons A and B (1, 2), and four triterpenoids (3–6) were isolated...     

A new para-quinone-type flavan from the leaves of Ilex centrochinensis and its anti-inflammatory activities

A new para-quinone-type flavan, (2S)-7-methoxy-3′,4′-dihydroxy-5,8-quinoflavan (1), together with three known compounds, were isolated from the leaves of Ilex centrochinensis. Their structures were elucidated by detailed spectroscopic analyses for new structure and in comparison with published data for known compounds. Moreover, the new compound was evaluated its cytotoxic and anti-inflammatory activities in vitro on LPS induced RAW 264.7 cells and the results showed that 1 has promising anti-inflammatory activities.     

蕲艾挥发油的化学成分及其体外抗氧化活性研究

目的：分析蕲艾挥发油的化学成分,对蕲艾挥发油体外抗氧化活性进行研究。方法：采用水蒸气蒸馏法提取蕲艾挥发油,运用气相色谱-质谱连用技术（GC-MS）分析蕲艾挥发油化学成分。通过清除1,1-二苯基-2-三硝基苯肼（DPPH）有机自由基法研究蕲艾挥发油的清除自由基作用,运用紫外-可见分光光度法测定蕲艾挥发油、抗氧化剂2,6-二叔丁基-4-甲基苯酚（BHT）和维生素E的清除率,并进行比较。结果：蕲艾挥发油检测到40种化学成分,初步鉴定了27种化合物,占总挥发性成分89.12%,其化学成分主要为侧柏酮（25.17%）、桉油精（23.42%）、樟脑（8.58%）、α-柏酮（7.76%）、4-萜品醇（4.7%）和冰片（3.34%）等。蕲艾挥发油的体外抗氧化试验表明,清除DPPH能力从强至弱的顺序为BHT > 蕲艾挥发油 > 维生素E。结论：蕲艾挥发油主要由酮类和萜类组成,并具有较好的体外抗氧化活性。     

龙爪槐叶和茎中挥发油的GC-MS分析及活性研究

目的 分析龙爪槐叶和茎挥发油中的化学成分,并考察挥发油的活性.方法 采用超临界CO2萃取龙爪槐叶和茎的挥发油,并用GC-MS法分析其化学成分;考察挥发油的体外抗菌及抗氧化活性.结果 从龙爪槐叶的挥发油中鉴定了49个化合物,主要有棕榈酸(7.86％)、亚油酸(5.80％)、4-乙烯基-2-甲氧基苯酚(5.32％)、4-乙基-2-甲氧基苯酚(5.20％)、Z-3-己烯-1-醇(5.11％)、叶绿醇(4.77％)和大马士酮(4.47％);从茎的挥发油中鉴定了31个化合物,主要有正己醇(5.92％)、3-烯丙基-6-甲氧基苯酚(4.63％)和3-甲基丁醛(4.12％).叶挥发油对大肠杆菌、金黄色葡萄球菌的抑制作用较强,其最小抑菌浓度(MIC)分别为0.062、0.031 mg·mL-1,同时对DPPH自由基、亚硝酸盐、ABTS、超氧阴离子也有较强的清除作用.结论 龙爪槐叶的挥发油具有较强的抗菌、抗氧化活性,具开发利用价值.