Chemical constituents from the whole herbs of Peperomia tetraphylla and their chemotaxonomic significance

Our studies report the isolation of seventeen compounds (1–17), which include three phenolic acids (12–14), seven flavonoids (3, 6, 8, 11, 15–17), four secolignans (1, 2, 5 and 9), one tetrahydrofuran lignin (10) and two alkaloids (4 and 7). These compounds have been obtained from the Peperomia tetraphylla using chromatographic methods. Their structures were confirmed based on spectroscopic methods. Among them, five compounds (4, 7, 8, 11 and 15) were found in the family, four compounds (3 and 12–14) were firstly reported from genus Peperomia, and four compounds (6, 9, 16 and 17) were firstly obtained from this species. Furthermore, the chemotaxonomic significance of these ingredients from the whole plants of P. tetraphylla has been discussed in detail.     

马尾松松针中化学成分的分离与鉴定

利用Diaion HP-20、Toyopearl HW-40及硅胶柱色谱进行分离纯化,研究松科(Pinaceae)植物马尾松(Pinus,massoniana Lamb．)松针的化学成分。从马尾松松针水煎液的正丁醇部位分离得到了4个化合物,根据理化性质和光谱数据分别鉴定为：(7S,8R)-4,9′-二羟基-3,3′-二甲氧基-7,8-二氢苯并呋喃-1′-丙基新木脂素-9-O-β-D-吡喃葡萄糖苷(1),对羟基苯基-2-丁酮(2),香草酸(3),氢醌(4)。这4个化合物均为首次从本植物中分离得到。     

Minor phenolics from Crinum bulbispermum bulbs

From the bulbs of Crinum bulbispermum Milne, four new minor compounds were isolated viz. 4-hydroxy-2',4'-dimethoxydihydrochalcone (1), 4,5-methylenedioxy-4'-hydroxy-2-aldehyde[1,1'-biphenyl] (4), hippacine (6), and 4'-hydroxy-7-methoxyflavan-3-ol (7). In addition, four known compounds were isolated and identified as 2(S),3',4'-dihydroxy-7-methoxy flavan (2), isolarrien (3), isoliquiritigenin (5) and liquiritigenin (8). The structures of the isolated compounds were established by spectral evidence.     

Alkaloids from Ruta montana

Two known and four new quinoline and 4-quinolone type alkaloids were isolated from Ruta montana collected from Rommani (Morocco). The known compounds were 1-methyl-4-methoxy-2-quinolone and evolitrine. The structures of the new compounds were established from 1D and 2D NMR experiments including HMQC, HMBC and MS spectral methods as 2-(nonan-8-one)-(1H)-4-quinolone, 2-(nonan-8-one)-4-methoxy-quinoline, 2-(nonan-8-one)-N-methyl-4-quinolone and 2-(decan-9-one)-N-methyl-4-quinolone.     

杠柳枝皮的化学成分研究(英文)

将杠柳枝皮粉末的乙醇提取物悬浮于水后,依次用石油醚、乙酸乙酯和正丁醇萃取.对乙酸乙酯萃取物采用各种柱层析进行多次分离后得到4个化合物,经波谱分析,鉴定它们的结构分别为β-香树素乙酸酯(1)、β-香树素(2)、periplogenin(3)和perilocoside N(4),其中化合物1和2是首次从该植物中分离得到.     

4-S-cysteaminylphenol and its analogues as substrates for tyrosinase and monoamine oxidase

A phenolic amine compound, 4-S-cysteaminylphenol (4-S-CAP), was found to cause a selective destruction of follicular melanocytes. It was also recently found that 4-S-CAP can be a substrate for both tyrosinase and plasma monoamine oxidase (MAO). Both of these enzymes are capable of producing cytotoxic intermediates through their interaction with 4-S-CAP. To study the mechanism of selective melanocytotoxicity of phenolic amine compounds, we compared the in vivo depigmenting potency of 4-S-CAP and its three analogues; i.e., 4-S-HomoCAP, alpha-methyl(Me)-4-S-CAP and N,N-dimethyl(DiMe)-4-S-CAP, using black hair follicles. All four of these phenolic amine compounds possessed depigmenting potency. In this study we examined the kinetics of tyrosinase and MAO by these four compounds. 4-S-CAP and 4-S-HomoCAP were the substrates of both tyrosinase and MAO, whereas alpha-Me-4-S-CAP and N,N-DiMe-4-S-CAP were the substrates of tyrosinase alone. The rate of o-quinone formation by tyrosinase was not in parallel to the in vivo depigmenting potency of the tested compounds. It is therefore indicated that plasma MAO is not the enzyme directly responsible for the production of the melanocytotoxic intermediates from the phenolic amine compounds. We also found that the observed in vivo depigmentation results from complex processes involving the amount of o-quinone formed and the intracellular interaction of o-quinone with protein species.     

红背山麻杆化学成分的研究

采用柱色谱技术从红背山麻杆叶子的60％乙醇提取物中分离得到4个黄酮苷和2个其他类化合物.根据理化性质及波谱方法分别鉴定为:芹菜素-6-C-D-葡萄糖苷(1)、芹菜素-7-O-芸香糖苷(2)、芹菜素-7-O-β-(2″-O-α-鼠李糖基)葡萄糖醛酸苷(3)、木犀草素-7-O-α-L-鼠李糖(1→6)-β-D-葡萄糖苷(4)、没食子酸乙酯(5)、β-胡萝卜苷(6).以上化合物均为首次从该植物中分离得到,其中化合物1～4为首次从山麻杆属中分离得到的黄酮苷.     

Theoretical study on benzoheterocycle based energetic materials,effect of heterocyclic-fused,conjugation, hydrogen bond,and substitutional group on the detonation performance

In this paper, four series of benzoheterocycle based energetic materials (EMs) have been designed to plan out a strategy to improve the density and safety of EMs, such as combining the insensitive group with aminobenzene ring and the high energetic nitramine explosives, benzo-heterocycle mother ring, designing multi-nitrogen heterocycles with a conjugated system containing N-N and C-N high energy bonds, and hydrogen bonding. Their optimized structure and detonation properties were first calculated and discussed using DFT methods. After calculation, these designed explosives all showed good detonation from 7352 m/s to 8788 m/s. Among them, the compounds with six nitro groups, 1c, 2c, 3c, and 4c, exhibit better performance and rather poor impact sensitivity. However, we found that the compounds with five nitro groups and one amino group have a limited performance reduction and a rapid stability improvement. These four compounds, 1b, 2b, 3b, and 4b, have good detonation performance and better stability. Moreover, the synthesis routes for these four compounds were also designed. The precursor 4–0 and mononitro product 4–1 were successfully synthesized. Their 1H NMR, single crystal, and elemental analysis were also done to verify the structures.     

Bio-assay guided isolation and identification of α-glucosidase inhibitors from the leaves of Aquilaria sinensis

Eight α-glucosidase inhibitors including four new compounds were isolated from the 70% aqueous ethanolic extract of leaves of Aquilaria sinensis (Lour.) Gilg by activity-directed fractionation and purification processes. The ethanolic extract was first separated into petroleum ether, ethyl acetate, n-butanol and water soluble fractions and screened for inhibitory activity against α-glucosidase. Further activity-directed investigation lead to the isolation of four new compounds with moderate inhibitory activity, viz, aquilarisinin (1), aquilarisin (2), hypolaetin 5-O-β-D-glucuronopyranoside (3) and aquilarixanthone (4) from the n-butanol fraction, and four known compounds showing potent activity including mangiferin (5), iriflophenone 2-O-α-L-rhamnopyranoside (6), iriflophenone 3-C-β-D-glucoside (7) and iriflophenone 3,5-C-β-D-diglucopyranoside (8) from the most potent ethyl acetate fraction. The structures of these compounds were determined by extensive spectroscopic analyses, including IR, UV, ESIMS, HRESIMS, 1D and 2D NMR.     

Discovery of a series of acrylic acids and their derivatives as chemical leads for selective EP3 receptor antagonists

A series of acrylic acids and their structurally related compounds were evaluated for their binding affinity to four EP receptor subtypes (EP1-4). Starting from the initial hit 3, which was discovered in our in-house library, compounds 4 and 5 were identified as new chemical leads as candidates for further optimization towards a selective EP3 receptor antagonist. The identification process of these compounds and their pharmacokinetic profiles are presented.     

醉鱼草果实水部位化学成分及神经保护活性研究

为研究醉鱼草果实水部位化学成分及其神经保护作用,利用多种色谱分离技术从醉鱼草果实水部位中分离得到10个化合物。结合现代光谱技术对分离得到的化合物进行结构鉴定,分别为密蒙花苷C(1)、异毛蕊花糖苷(2)、毛蕊花糖苷(3)、4′-hydroxyphenyl ethyl vanillate(4)、6-O-香草酰筋骨草苷(5)、syringaresinol-4′-O-β-D-glucopyranoside(6)、刺五加苷B(7)、松柏苷(8)、醉鱼草皂苷Ⅳb(9)、6-O-(3"-O-p-coumaroyl-α-L-rhamnopyranosyl)catalpol(10),其中化合物4、6、7、8、10为首次从醉鱼草属植物中分离得到,化合物2、3为首次从醉鱼草果实中分离得到;利用MPP+诱导的SH-SY5Y细胞模型对化合物1、5、6、7的神经保护作用进行活性筛选,结果显示四个化合物均能使细胞存活率显著提高。     

Phenolic compounds and flavonoids as plant growth regulators from fruit and leaf of Vitex rotundifolia

Five phenolic compounds, 4-hydroxybenzoic acid methyl ester (1), vanillic acid methyl ester (2), 4-hydroxy benzaldehyde (3), 4-hydroxybenzoic acid (4) and ferulic acid (5), and four flavonoids, 5,5'-dihydroxy-4',6,7-trimethoxyflavanone (6), luteolin (7), vitexicarpin (8) and artemetin (9), were isolated from fruits and leaves of Vitex rotundifolia L. The biological activities of these nine compounds have been examined using a bioassay with lettuce seedlings.     

Anti-fungal effects of phenolic amides isolated from the root bark of Lycium chinense

Four phenolic amides, dihydro-N-caffeoyltyramine (1), trans-N-feruloyloctopamine (2), trans-N -caffeoyltyramine (3), and cis-N-caffeoyltyramine (4), were isolated from an ethyl acetate extract of the root bark of Lycium chinense Miller. All had an anti-fungal effect; compounds 1-3 were potent at 5-10 microg ml(-1) and were without hemolytic activity against human erythrocyte cells. Compound 4 was active at 40 microg ml(-1). All four compounds impeded the dimorphic transition of pathogen, Candida albicans.     

Furanoflavonoids from Pongamia pinnata fruits

Fruits of Pongamia pinnata afforded four new furanoflavonoids, pongapinnol A-D (1-4), and a new coumestan, pongacoumestan (5) along with thirteen known compounds 6-18. Compounds 16 and 17 are isolated for the first time from this plant. The structures of isolated compounds were elucidated on the basis of spectroscopic data interpretation.     

Phenylpropanoid and iridoid glycosides from Pedicularis lasiophrys.

Two new compounds, pedicularioside E and F, were isolated from whole plants of Pedicularis lasiophrys, along with the four known compounds, verbascoside, cistanoside C, cistanoside D and 8-epiloganin. On the basis of spectral and chemical evidence, pedicularioside E and F were identified to be 1'-O-beta-D-(3-methoxy-4-hydroxy-beta-phenyl)-ethyl-6'-O-feruloyl- alpha-L-(2-acetyl)-rhamnosyl-(1----3')-4'-acetylglucopyranoside and shanzhisin methyl ester cellobioside, respectively.     

Macrocarpins A-D, new cytotoxic nor-triterpenes from Maytenus macrocarpa

Macrocarpins A (1), B (2), C (3) and D (4), four new nor-triterpenes, have been isolated from the roots of Maytenus macrocarpa. The structures were established by spectroscopic examinations. Natural compounds 1, 2, 4 and the acetyl derivative 1a are cytotoxic against four tumoral cell lines with IC50 values ranging between 0.4 and 5.2 microM.     

Comparative analysis of the volatile fraction of fruit juice from different Citrus species

The volatile composition of fruit from four Citrus varieties (Powell Navel orange, Clemenules mandarine, and Fortune mandarine and Chandler pummelo) covering four different species has been studied. Over one hundred compounds were profiled after HS-SPME-GC-MS analysis, including 27 esters, 23 aldehydes, 21 alcohols, 13 monoterpene hydrocarbons, 10 ketones, 5 sesquiterpene hydrocarbons, 4 monoterpene cyclic ethers, 4 furans, and 2 aromatic hydrocarbons, which were all confirmed with standards. The differences in the volatile profile among juices of these varieties were essentially quantitative and only a few compounds were found exclusively in a single variety, mainly in Chandler. The volatile profile however was able to differentiate all four varieties and revealed complex interactions between them including the participation in the same biosynthetic pathway. Some compounds (6 esters, 2 ketones, 1 furan and 2 aromatic hydrocarbons) had never been reported earlier in Citrus juices. This volatile profiling platform for Citrus juice by HS-SPME-GC-MS and the interrelationship detected among the volatiles can be used as a roadmap for future breeding or biotechnological applications.     

Detection of potential volatile inhibitory compounds produced by endobacteria with biocontrol properties towards <Emphasis Type="Italic">Fusarium oxysporum</Emphasis> f. sp. <Emphasis Type="Italic">cubense</Emphasis> race 4

A variety of volatile compounds were detected from six endobacteria isolated from different host species. From this, only two isolates (LCB01 and AVA02) produced volatile compounds capable of inhibiting the growth of the pathogenic Fusarium oxysporum f. sp. cubense race 4 (FocR4). Inhibition by volatile compounds produced by isolate LCB01 (Herbaspirillum spp.) was the most effective with 20.3% inhibition towards FocR4. Volatile compounds profiles indicated that inhibition may be attributed to the presence of single compounds such as 2-pentane 3-methyl, methanethiol and 3-undecene, or their action synergistically. Both methanethiol and 3-undecene were also produced by AVA02 (Pseudomonas spp.), but the absence of 2-pentane 3-methyl seemed to have affected the inhibitory effect with only 1.4% inhibition. The absence or the low levels of the three compounds in the other four isolates resulted in no inhibition of FocR4. These observations strongly suggest the antifungal nature of the three volatile compounds towards FocR4.     

Algicidal Activity of Marine Alteromonas sp. KNS-16 and Isolation of Active Compounds

The KNS-16 algicidal strain was isolated from a harmful alga bloom (HAB) area and identified as Alteromonas sp. based on 16S rDNA sequencing. The KNS-16 strain was found to control HABs by producing algicidal compounds in an indirect interaction. Four active compounds were isolated from KNS-16 culture, and their structures were analyzed by interpreting nuclear magnetic resonance and mass spectroscopy data. The structures were identified as 2-undecen-1'-yl-4-quinolone (1), 2-undecyl-4-quinolone (2), 3-hexyl-6-pentyl-4-hydroxyl-2H-pyran-2-one (3), and 6-heptyl-3-hexyl-4-hydroxyl-2H-pyran-2-one (4). Compound 1 was most active against HABs such as Heterosigma akashiwo, Cochlodinium polykrikoides, and Alexandrium tamarense with LC(50) values of 0.5-1.1 μg/mL. The four compounds exhibited high LC(50) values against aquaculture algae such as Tetaselmis suecica, Isochrysis galbana, and Pavlova lutheri at 39-66 μg/mL. Based on toxicity tests on the brine shrimp Artemia salina and the rotifer Brachionus rotundiformis, the four compounds showed ranges of 409-608 and 189-224 μg/mL of LC(50) for the two organisms, respectively. The LC(50) values for juvenile fish of Sebastes schlegelii were 284-304 μg/mL.