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1.
A methanol extract of avocado fruits showed potent inhibitory activity against acetyl-CoA carboxylase, a key enzyme in fatty acid biosynthesis. The active principles were isolated and identified as (5E,12Z,15Z)-2-hydroxy-4-oxoheneicosa-5,12,15-trienyl (1), (2R,12Z,15Z)-2-hydroxy-4-oxoheneicosa-12,15-dienyl (2), (2R*,4R*)-2,4-dihydroxyheptadec-16-enyl (3) and (2R*,4R*)-2,4-dihydroxyheptadec-16-ynyl (4) acetates by instrumental analyses. The IC50 of the compounds were 4.0 x 10(-6), 4.9 x 10(-6), 9.4 x 10(-6), and 5.1 x 10(-6) M, respectively.  相似文献   

2.
The synthesis of methyl (?)-shikimate [(?)-2] was achieved via lipase-catalyzed optical resolution of (1S*,4R*,5R*)-4-hydroxy-6-oxabicyclo[3.2.1]oct-2-en-7-one (3). Transesterification of (±)-3 and vinyl acetate with lipase MY and subsequent hydrolysis gave optically pure (?)-3. This compound was converted to (?)-2 in two steps.  相似文献   

3.
Bestatin, [(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl]-(S)-leucine, inhibited aminopeptidase B and leucine aminopeptidase in a competitive manner and their Ki values were calculated to be 6 × 10?8 and 2 × 10?8M, respectively. Among all stereoisomers of bestatin synthesized, those which have a (2S)-configuration in the 3-amino-2-hydroxy-4-phenylbutanoyl moiety showed marked inhibition against aminopeptidase B and leucine aminopeptidase compared with the other isomers which have (2R)-configuration. One of the isomers, [(2S,3S)-3-amino-2-hydroxy-4-phenylbutanoyl]-(R)-leucine, showed somewhat stronger activity against aminopeptidase B than bestatin. Aminopeptidase B appears to be a metallo-exopeptidase. It is proposed that bestatin and its active isomers are effective due to a mechanism other than a chelating action at the active center.  相似文献   

4.
Two diastereoisomers, 5R,6R-5-hydroxy-6(9α)-oxido-11α,15S-dihydroxyprost-13-enoic acid (7) and 5S,6S-5-hydroxy-6(9α)-oxido-11α,15S-dihydroxyprost-13-enoic acid (10) were synthesized for evaluation as possible biosynthetic intermediates in the enzymatic transformation of PGH2 or PGG2 into PGI2. The synthetic sequence entails the stereospecific reduction of the 9-keto function in PGE2 methyl ester after protecting the C-11 and C-15 hydroxyls as tbutyldimethylsilyl ethers. The resulting PGF derivative was epoxidized exclusively at the C-5 (6) double bond to yield a mixture of epoxides, which underwent facile rearrangement with SiO2 to yield the 5S,6S and 5R,6R-5-hydroxy-6(9α)-oxido cyclic ethers. It was found that dog aortic microsomes were unable to transform radioactive 9β-5S,6S[3H] or 9β-5R,6R[3H]-5-hydroxy-6(9α)-oxido cyclic ethers into PGI2. Also, when either diastereoisomer was included in the incubation mixture, neither isomer diluted the conversion of [1-14C]arachidonic acid into [1-14C]PGI2.  相似文献   

5.
In order to make a progress in discovering a new agents for chemotherapy with improved properties and bearing in mind the fact that substituted 3-hydroxy-3-pyrrolin-2-ones belong to a class of biologically active compounds, series of novel 1,5-diaryl-4-(2-thienylcarbonyl)-3-hydroxy-3-pyrrolin-2-ones were synthesized and characterized by spectral (UV–Vis, IR, NMR, ESI-MS), X-ray and elemental analysis. All compounds were examined for their cytotoxic effect on human cancer cell lines HeLa and MDA-MB 231 and normal fibroblasts (MRC-5). Four compounds, 3-hydroxy-1-(p-tolyl)-4-(2-thienylcarbonyl)-5-(4-chlorophenyl)-2,5-dihydro-1H-pyrrol-2-one (D10), 3-hydroxy-1-(3-nitrophenyl)-4-(2-thienylcarbonyl)-5-(4-(benzyloxy)phenyl)-2,5-dihydro-1H-pyrrol-2-one (D13), 3-hydroxy-1-(4-nitrophenyl)-4-(2-thienylcarbonyl)-5-(4-(benzyloxy)phenyl)-2,5-dihydro-1H-pyrrol-2-one (D14), and 3-hydroxy-1-(4-chlorophenyl)-4-(2-thienylcarbonyl)-5-(4-(benzyloxy)phenyl)-2,5-dihydro-1H-pyrrol-2-one (D15), that showed the highest cytotoxicity against malignant cells and the best selectivity towards normal cells were selected for further experiments. Results obtained by investigating mechanisms of cytotoxic activity suggest that selected 3-hydroxy-3-pyrrolin-2-one derivatives in HeLa cells induce apoptosis that is associated with S phase arrest (D13, D15, and D10) or unrelated to cell cycle distribution (D14). Additionally, to better understand their suitability for potential use as anticancer medicaments we studied the interactions between biomacromolecules (DNA or BSA) and D13 and D15. The results indicated that D13 and D15 have great affinity to displace EB from the EB-DNA complex through intercalation [Ksv = (3.7 ± 0.1) and (3.4 ± 0.1) × 103 M−1, respectively], an intercalative mode also confirmed through viscosity measurements. Ka values, obtained as result of fluorescence titration of BSA with D13 and D15 [Ka = (4.2 ± 0.2) and (2.6 ± 0.2) × 105 M, respectively], support the fact that a significant amount of the tested compounds could be transported and distributed through the cells. In addition, by DNA and BSA molecular docking study for D13, D14 and D15 is determined and predicted the binding mode and the interaction region.  相似文献   

6.
A series of 3(R)-aminopyrrolidine derivatives were designed and synthesized for JAK1-selective inhibitors through the modification of tofacitinib’s core structure, (3R,4R)-3-amino-4-methylpiperidine. From the new core structures, we selected (R)-N-methyl-N-(pyrrolidin-3-yl)-7H-pyrrolo[2,3-d]pyrimidin-4-amine as a scaffold for further SAR studies. From biochemical enzyme assays and liver microsomal stability tests, (R)-3-(3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)pyrrolidin-1-yl)-3-oxopropanenitrile (6) was chosen for further in vivo test through oral administration. Compound 6 showed improved selectivity for JAK1 compared to that of tofacitinib (IC50 11, 2.4?×?102, 2.8?×?103, and 1.1?×?102?nM for JAK1, JAK2, JAK3, and TYK2, respectively). In CIA and AIA model tests, compound 6 exhibited similar efficacy to tofacitinib citrate.  相似文献   

7.
(2R*,4S*,6S*,αS*)- and (2R,4R,6RS)-Streptovitacin-C2 (STV-C2) (1a and 1b) were synthesized by an aldol condensation of (2R*,4S*)- or (2R,4R)-2,4-dimethyl-2-trimethylsiloxy-1-cyclohexanone (15a or 15b) with 4-(2-oxoethyl)-2,6-piperidinedione (16), which was followed by desilylation of the products. The stereochemistry of the synthesized STV-C2 isomers (1a and 1b) was elucidated by NMR. STV-C2 isomers (1a and 1b) did not show strong antimicrobial activity against Saccharomyces cerevisiae and Pyricularia oryzae.  相似文献   

8.
A highly sensitive and selective resonance scattering spectral assay was proposed for the determination of horseradish peroxidase (HRP), based on its catalytic effect on the H2O2 oxidation of KI to form I3?. The I3? combined respectively with rhodamine (Rh) dye such as rhodamine S (RhS), rhodamine 6G (Rh6G), rhodamine B (RhB) and butyl‐rhodamine B (b‐RhB), to form association particles (Rh‐I3)n. The four Rh systems all exhibit a stronger resonance scattering (RS) peak at 424 nm. For the RhS, Rh6G, RhB and b‐RhB systems, HRP concentration in the range of 3.2 × 10?12 to 4.8 × 10?9, 2 × 10?11 to 3.2 × 10?9, 1.6 × 10?11 to 3.2 × 10?9 and 1.6 × 10?11 to 4 × 10?9 g/mL was linear to its RS intensity at 424 nm, with a detection limit of 2.2 × 10?12, 2.5 × 10?12, 4.4 × 10?12 and 2.6 × 10?12 g/mL, respectively. This RhS system was most sensitive and stable, and was applied for the determination of HRP in the hepatitis B surface antibody labeling HRP and water samples, with satisfactory results. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

9.
Proteomic approaches have unique advantages in the identification of biological pathways that influence physical frailty, a multifactorial geriatric syndrome predictive of adverse health outcomes in older adults. To date, proteomic studies of frailty are scarce, and few evaluated prefrailty as a separate state or examined predictors of incident frailty. Using plasma proteins measured by 4955 SOMAmers in the Atherosclerosis Risk in Community study, we identified 134 and 179 proteins cross-sectionally associated with prefrailty and frailty, respectively, after Bonferroni correction (p < 1 × 10−5) among 3838 older adults aged ≥65 years, adjusting for demographic and physiologic factors and chronic diseases. Among them, 23 (17%) and 82 (46%) were replicated in the Cardiovascular Health Study using the same models (FDR p < 0.05). Notably, higher odds of prefrailty and frailty were observed with higher levels of growth differentiation factor 15 (GDF15; pprefrailty = 1 × 10−15, pfrailty = 2 × 10−19), transgelin (TAGLN; pprefrailty = 2 × 10−12, pfrailty = 6 × 10−22), and insulin-like growth factor-binding protein 2 (IGFBP2; pprefrailty = 5 × 10−15, pfrailty = 1 × 10−15) and with a lower level of growth hormone receptor (GHR, pprefrailty = 3 × 10−16, pfrailty = 2 × 10−18). Longitudinally, we identified 4 proteins associated with incident frailty (p < 1 × 10−5). Higher levels of triggering receptor expressed on myeloid cells 1 (TREM1), TAGLN, and heart and adipocyte fatty-acid binding proteins predicted incident frailty. Differentially regulated proteins were enriched in pathways and upstream regulators related to lipid metabolism, angiogenesis, inflammation, and cell senescence. Our findings provide a set of plasma proteins and biological mechanisms that were dysregulated in both the prodromal and the clinical stage of frailty, offering new insights into frailty etiology and targets for intervention.  相似文献   

10.
The effect of hormone-like compounds at different concentrations: 2,4-D (2 × 10?6; 2 × 10?5; and 2 × 10?4M) and 1-NAA (2 × 10?7; 2 × 10?6; 2 × 10?5; 4 × 10?5, and 6 × 10?5 M) on the growth and production of phenolic compounds, including flavans and lignin, was investigated in callus culture of tea plant (Camellia sinensis L., a highly productive strain IFR ChS-2). The growth of the culture was vigorous, and production of phenolic compounds therein was efficient in the medium containing 2 × 10?5 M 2,4-D. Substitution of 1-NAA for 2,4-D in all the cases decelerated the growth of the culture. These changes were more pronounced when 2 × 10?7 and 2 × 10?6 M 1-NAA was used; in this case, biomass accumulation decreased by 1.5–2.0 times as compared with control material growing on the medium with 2 × 10?5 M 2,4-D. In the presence of 1-NAA, the content of total soluble phenolic compounds and flavans in the calli rose by 30% on the average as compared with control material. Accumulation of lignin remained essentially the same. Therefore, the replacement of 2,4-D with 1-NAA in the nutrient medium used for the growing of highly productive strain of tea plant callus did not induce considerable changes in its ability to produce phenolic compounds.  相似文献   

11.
The second-order rate constants (M?1sec?1, 25°C, pH 8.2, I = 0.15 M) for the oxidation to (semi-met)0of deoxyhemerythrin from Phascolopsis gouldii (P.g.) and Themiste zostericola (T.z.) have been determined for Fe(CN)5(4-NH2py)2? (3.6 × 104 T.z.,2.8 × 102P.g.),Fe(CN)5NH32?(2.4 × 104 T.z.), Fe(CN)63? (1.0 × 105 T.z.,1.4 × 102P.g.), Fe(CN)5PPh32? (7.3 × 105T.z.), and Fe(CN)4dipy- (~6 × 106 T.z.,7.5 × 104 P.g.). Corresponding rate constants for the oxidation of (semi-met)R to met are: Fe(CN)5(4-NH2py)2? (1.2 × 103 P.g.), Fe(CN)63? (3.4 × 105 T.z., 4.5 × 10 Fe(CN)5PPh32? (4.4 × 104P.g.), Fe(CN)4dipy? (1.7 × 105P.g.), and Coterpy23+ (5.1 P.g.) The rates of oxidation of deoxy- and (semi-met)R myohemetythrin by Fe(CN)63? were too rapid for stopped-flow measurement. The Marcus relationship for cross-reactions was successfully applied to these data.  相似文献   

12.
This study examines the effects of ionizing radiation (control, 4 × 1016, 6 × 1016, 9.5 × 1016, and 15 × 1016 Ar+/cm2) on some physio-biochemical and molecular responses of highland barley (Hordeum vulgare L. ssp. vulgare) under salt stress for 0, 24, 48, and 96 h. The growth parameters of highland barley were the highest at the dose of 9.5 × 1016 Ar+/cm2, but the lowest at 15 × 1016 Ar+/cm2 dose. The malondialdehyde (MDA) content increased with increasing irradiation dose and peaked at 15 × 1016 Ar+/cm2 during stress treatments. The activities of antioxidant enzymes and proline accumulation showed different changes than MDA following ion beam irradiation toward stress conditions, at the dose of 15 × 1016 Ar+/cm2, antioxidant enzyme activities and proline content were the lowest compared with their corresponding controls, while at the dose of 9.5 × 1016 Ar+/cm2 antioxidant enzyme activities and proline content were the highest. Moreover, the expression of salt-related gene followed the same pattern as that of the antioxidant enzymes. Our results suggest that the dose of 9.5 × 1016 Ar+/cm2 alleviates salt stress by modulating the physio-biochemical responses and eliciting the stress signal transduction in plants.  相似文献   

13.
The acute effects of beraprost sodium (sodium (±)-(1R*, 2R, 3aS*, 8bS*)-2, 3, 3a 8b-tetrahydro-2-hydroxy-l-((E)-(3S*)-3-hydroxy-4-methylI-octen-6-yny1] -1H-cyclopenta [b] bensofuran-5-butyrate), a stable analogue of prostaglandin I2 which works as a vasodilator and anti-platelet agent, were investigated in patients with non-insulin dependent diabetes mellitus. Its effects on the dorsal pedis artery were examined using a new real-time two-dimensional Doppler ultrasonographic technique and by laser blood flowmetry. Before and 60 min after oral administration of beraprost sodium (Dolner® 40 μg) and elastase (Elaszym® 1800 U), the cross-sectional area (CSA) of the dorsal pedis artery and its blood flow index (BFI), calculated from the maximum flow velocity and area, were determined. Dermal microcirculatory blood volume (MBV) was also measured by laser blood flowmetry. In the beraprost sodium group, the CSA, BFI and MBV were significantly increased, while in the elastase group, no significant changes were observed. These result suggest that beraprost sodium has a beneficial effect on diabetic macro- and microangiopathy.  相似文献   

14.
Two new ent-kauren-19-oic acid derivatives, ent-14S*-hydroxykaur-16-en-19-oic acid and ent-14S*,17-dihydroxykaur-15-en-19-oic acid together with eleven known compounds ent-kaur-16-en-19-oic acid, ent-kaur-16-en-19-al, ent-12β-hydroxykaur-16-en-19-oic acid, ent-12β-acetoxykaur-16-en-19-oic acid, 8R,13R-epoxylabd-14-ene, eudesm-4(15)-ene-1β,6α-diol, (?)-7-epivaleran-4-one, germacra-4(15), 5E,10(14)-trien-9β-ol, acetyl aleuritolic acid, β-amyrin, and stigmasterol were isolated from the stem bark of Croton pseudopulchellus (Euphorbiaceae). Structures were determined using spectroscopic techniques. Ent-14S*-hydroxykaur-16-en-19-oic acid, ent-kaur-16-en-19-oic acid, ent-12β-hydroxykaur-16-en-19-oic acid, ent-12β-acetoxykaur-16-en-19-oic acid and 8R,13R-epoxylabd-14-ene were tested for their effects on Semliki Forest virus replication and for cytotoxicity against human liver tumour cells (Huh-7 strain) but were found to be inactive. Ent-kaur-16-en-19-oic acid, the major constituent, showed weak activity against the Plasmodium falciparum (CQS) D10 strain.  相似文献   

15.
The sesquiterpene lactone, 2-methyl-2-butenoic acid dodecahydro-4-(hydroxymethyl)-10a-methyl-8-methylene-3,7-dioxooxineno[5,6]cyclodeca[1,2-b]furan-9-yl ester [1aR*-[1aS*,4R*,5aS*,8aR*,9R*(E)]], argophyllone-B, was isolated from acetone extracts from the leaves of Helianthus argophyllus. Its structure has been determined by single crystal X-ray analysis. Complete 1H NMR and 13C NMR assignments have been made.  相似文献   

16.
Robert H. White 《Chirality》1996,8(4):332-340
The configuration at the C-9 of methanopterin (MPT) has been determined by comparing the circular dichroism (CD) spectra of MPT and its hydrolytic fragment, 1-[4-[[1-(2-amino-7-methyl-4-hydroxy-6-pteridinyl)-ethyl]amino]phenyl]-1-deoxy-D -ribitol (HP-1), with the CD spectra of a series of model compounds of known stereochemistry. These compounds included (S)-6-[1-(4-carboxymethylanilino)ethyl]pterin, (S-6(1-hydroxyethyl)-7-methylpterin, (S-6-(1-hydroxyethyl)pterin, (R)-6-(1-phenoxyethyl)pterin, D (+)-neopterin, and L -biopterin. From this comparison it was concluded that MPT has the R configuration at C-9 and is thus configurationally related to D (+)-neopterin, which has the S configuration at C-1. From previous work establishing the relative stereochemistry at C-6, C-7, and C-9 of N5-N10-methenyl-5,6,7,8-tetrahydromethanopterin (N5-N10-methenyl-H4MPT) as R, S, and R, respectively, it is clear that the remaining asymmetric carbons at C-6 and C-7 of H4MPT have the S and S configuration, respectively. Comparison of these latter two positions to the equivalent carbons in 5,6,7,8-tetrahydrofolate (H4folate) show that the steps involved in the biological reduction of MPT to H4MPT occur with the same stereochemical outcome as those involved in the biological reduction of folate to H4folate. © 1996 Wiley-Liss, Inc.  相似文献   

17.
Two new eudesmane sesquiterpenoids artanoate (1) and eudesmanomolide (2) were isolated from the aerial parts of Artemisia anomala S. Moore. Their structures were elucidated as methyl (4R, 5S, 6S, 7S, 10R)-1-oxo-4, 6-dihydroxy-eudesma-2, 11 (13)-dien-12-oate (1) and (1R, 5R, 6R, 10R)-3, 13-diacetoxy-1-hydroxy-3, 7(11)-diene-12, 6-olide (2) on the basis of extensive spectroscopic analyses. Compound 1 showed cytotoxicity against HCT-8 cell lines with IC50 value of 9.13 μM, and compound 2 exhibited inhibitory activities against HCT-8 and A549 cell lines with IC50 values of 3.76 and 5.49 μM, respectively.  相似文献   

18.
Six compounds, eudesm-11(13)-en-4β,9β-diol, 15R,16-dihydroxy-3-oxoisopimar-9(11)-ene, 15S,16-dihydroxy-3-oxoisopimar-9(11)-ene, 1α-hydroxy-7-oxo-iso-anhydrooplopanone, 10α-hydroxy-11,13-dihydro-5-epi-psilostachyin, and 4β-hydroxypseudoguaian-12,6-olide 4-O-β-d-glucopyranoside, together with 12 known sesquiterpenes, were isolated from the leaves of Ambrosia arborescens. Structures were elucidated by 1D and 2D NMR spectroscopy including 1D-TOCSY, DQF-COSY, 2D-ROESY, HSQC, and HMBC experiments, as well as by ESI mass spectrometry. The absolute configuration of the 15,16-diol moiety in 15R,16-dihydroxy-3-oxoisopimar-9(11)-ene and 15S,16-dihydroxy-3-oxoisopimar-9(11)-ene was determined using Snatzke’s method. All compounds were evaluated for antiproliferative activity.  相似文献   

19.
The aerial parts of Aruncus dioicus var. kamtschaticus afforded five new monoterpenoids (1-5): 4-(erythro-6,7-dihydroxy-9-methylpent-8-enyl)furan-2(5H)-one (1, aruncin A), 2-(8-ethoxy-8-methylpropylidene)-5-hydroxy-3,6-dihydro-2H-pyran-4-carboxylic acid (2, aruncin B), 4-(hydroxymethyl)-6-(8-methylprop-7-enyl)-5,6-dihydro-2H-pyran-2-one-11-O-β-d-glucopyranoside (3, aruncide A), (3S,4S,5R,10R)-3-(10-ethoxy-11-hydroxyethyl)-4-(5-hydroxy-7-methylbut-6-enyl)oxetan-2-one-11-O-β-d-glucopyranoside (4, aruncide B), and (3S,4S,5R,7R)-5-(9-methylprop-8-enyl)-1,6-dioxabicyclo[3,2,0]heptan-2-one-7-(hydroxymethyl)-12-O-β-d-glucopyranoside (5, aruncide C). Compound 2 showed potent cytotoxicity against Jurkat T cells with an IC50 value of 17.15 μg/mL. In addition, compounds 7 and 10 exhibited moderate antioxidant activity with IC50 values of 46.3 and 11.7 μM, respectively.  相似文献   

20.
In moths, males can detect a distinct blend of several pheromone components by specialized olfactory receptor neurons (ORNs) on the antennae. Four candidate pheromone receptors (PR) with seven transmembrane domains were identified by homology cloning from the antennae of Spodoptera exigua (Sexi). Phylogenetic analyses reveal that all four odorant receptors (OR) belong to pheromone receptor subtypes. Expression patterns revealed that PRs were male-specific in the antenna except for SexiOR11, which was female antenna-biased. Functional analyses of these PRs were conducted using heterologous expression in Xenopus oocytes. SexiOR13 and SexiOR16 were all broadly activated by multiple pheromone components. SexiOR13 responded robustly to the critical pheromone component, Z9, E12-14:OAc and the minor pheromone component, Z9-14:OAc at a concentration of 10?4 M. Dose-response studies indicate that SexiOR13 was approximately 4 times more sensitive to Z9,E12-14:OAc (EC50 = 3.158 × 10?6 M) compared to Z9-14:OAc (EC50 = 1.203 × 10?5 M). While, SexiOR16 responded robustly to the secondary pheromone component Z9-14:OH with high sensitivity (EC50 = 9.690 × 10?7 M). However, similar tests of the five pheromones with SexiOR6 and SexiOR11 failed to elicit any response. These results provide basic knowledge to further advance research on the molecular mechanisms of pheromone reception.  相似文献   

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