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1.
The mixture of dl-α-alanine and d-glucose was roasted at 250° for about an hour in nitrogen atmosphere. From the volatile condensates were isolated and identified alkyl and acyl pyrroles, alkyl pyrrole-2-aldehydes, furfuryl pyrroles, alkyl pyrazines and furanic compounds. The identification of these compounds was based on the spectroscopic methods (MS, GC-MS and IR) and gas chromatographic analysis.  相似文献   

2.
An exo-β-1,3-glucanase was purified from the commercial enzyme preparation “Kitalase” which is a yeast cell wall lytic enzyme preparation. The purification procedures consisted of following steps: ammonium sulfate fraction, SP-Sephadex C-50 and CM-Cellulose C-32 column chromatography, and Sephadex G-100 gel filtration. The optimum pH value was 5.8, and the optimum temperature was 55°C. The enzyme was stable in the pH range of 5.1 to 9.8 and at temperatures below 53°C. The isoelectric point and the molecular weight were estimated to be pH 9.3 and 73000, respectively. The enzyme was shown to bypass β-1,6-linkaged branches to cleave β-1,3-linkages when scleroglucan was used as substrate. The Km values for laminariri, laminari-pentaose, laminaritetraose and laminaritriose were 0.16, 2.01, 2.24 and 1.34 mM, respectively.  相似文献   

3.
A series of novel, potent PPARα/γ dual agonists were synthesized and appraised. The most potent analogue, compound 2b demonstrated EC50 value of 0.012 ± 0.002 and 0.032 ± 0.01 μM, respectively, for hPPARα and hPPARγ in transactivation assay. Additionally, compound 2b demonstrated good glucose and lipid lowering effect in genetic diabetic (db/db) mice.  相似文献   

4.
A series of polymethyl-substituted piperidines linked to either a 6-methoxy-1,2,3,4-tetrahydronaphthalen-1-yl or a 6-methoxynaphthalen-1-yl moiety was generated with the aim of verifying a previously generated hypothesis: tetralin and naphthalene nuclei confer opposite activity at the σ1 receptor. Compounds 6, 9 and 10 displayed appreciable affinity at both σ subtypes, but none of the novel compounds displayed significant antiproliferative activity in MCF7wt and MCF7σ1 cell lines. The effect on bradikynin-triggered Ca2+ mobilization was studied as a methodology to suggest σ receptors mediated activity.  相似文献   

5.
Indole-5-carboxylic acids with 3-aryloxy-2-oxopropyl residues in position 1 have been found to be potent inhibitors of human cytosolic phospholipase A2α (cPLA2α). In course of structure-activity relationship studies, we investigated the effect of the substitution of the electrophilic ketone group in the middle part of the molecule by other polar residues, such as hydroxyimino, azido, acyloxy, acylamino, urea and carbamate, on enzyme inhibition. With an IC50 of 1.7 μM against cPLA2α from human platelets, the 4-fluorophenylcarbamate derivative 23f was the most active of the compounds tested.  相似文献   

6.
The 13C.n.m.r spectra of water-soluble and -insoluble glucans synthesized by enzymes isolated from six strains of Streptococcus mutans are interpreted. The glucans are shown to be composed primarily of α(1→3)- and α-(1→6)-linked glucosyl residues, and the relative abundance of each linkage is estimated from peak areas. Treatment of water-insoluble glucans with dextranase is found to result in water-soluble and -insoluble products, the former enriched in α-(1→6)-linkages and the latter in α-(1→3)-linkages. The structural conclusions arrived at by 13C-n.m.r. spectroscopy are consistent with data from methylation analysis and 1H-n.m.r. spectroscopy.  相似文献   

7.
Microorganisms that hydrolyze methyl 2-phenylpropionate (1) or reduce 4-phenyl-2-butanone (3) were screened from 250 type cultures. Several Aspergilli and two bacteria hydrolyzed ester 1, and Asp. sojae IAM 2703 preferentially hydrolyzed (R)-isomer of (±)-1, whereas Bacillus subtilis var. niger IFO 3108 and Mycobacterium smegmatis ATCC 10143 preferentially hydrolyzed (S)-isomer. The hydrolysis of the related esters of 1 with these organisms was also examined.  相似文献   

8.
9.
Novel series of N-(5-(arylcarbonyl)thiazol-2-yl)amides and N-(5-(arylcarbonyl)thiophen-2-yl)amides were discovered as potent retinoic acid receptor-related orphan receptor-gamma-t (RORγt) inhibitors. SAR studies of the RORγt HTS hit 6a led to identification of thiazole ketone amide 8h and thiophene ketone amide 9g with high binding affinity and inhibitory activity of Th17 cell differentiation. Compound 8h showed in vivo efficacy in both mouse experimental autoimmune encephalomyelitis (EAE) and collagen induced arthritis (CIA) models via oral administration.  相似文献   

10.
Abstract

Reaction of methyl 2-deoxy-2-C-(3-bromoacetoxypropyl)-α-D-arabinofuranosides, prepared from methyl 2,3-anhydro-α-D-ribofuranoside, with oligodeoxyribonucleotide (21mer) in acetonitrile-H2O (pH 7) and subsequent treatment with piperidine resulted in the cleavage of the nucleotide chain at the position G, A, and C.  相似文献   

11.
A series of 1-(6-methylpyridin-2-yl)-5-(quinoxalin-6-yl)-1,2,3-triazoles has been synthesized and evaluated for their ALK5 inhibitory activity. The 1-(6-methylpyridin-2-yl)-1,2,3-triazoles were assembled by Cu(I)-catalyzed azide–alkyne 1,3-dipolar cycloaddition. Following this, quinoxaline was introduced through Pd-catalyzed direct arylation. The synthesized 1-(6-methylpyridin-2-yl)-5-(quinoxalin-6-yl)-1,2,3-triazoles revealed significant selectivity differences with respect to p38α MAP kinase. In particular, 12k showed 80.8% ALK5 inhibitory activity at a concentration of 10 μM and IC50 value of 4.69 μM, but did not show p38α MAP kinase inhibitory activity (?1.94% inhibition at a concentration of 10 μM).  相似文献   

12.
Abstract

2′-5′ and 3′-5′ linked 2-aminoadenylyl-2-aminoadenosines [(2′-5′)n2Apn2A (1) and (3′-5′)n2Apn2A (2)] were synthesized by condensation of 5′-O-monomethoxytrityl-N 2 N 6-dibenzoyl-2-aminoadenosine and N 2,N 6,2′,3′-O-tetrabenzoyl-2-aminoadenosine 5′-phosphate using dicyclohexylcarbodiimide (DCC). The conformational properties of these dimers 1 and 2 were examined by UV, NMR and CD spectroscopy. The results reveal that the 2′-5′-isomer 1 takes a stacked conformation, which contains a larger base-base overlap and is more stable against thermal perturbation with respect to the 3′-5′-isomer 2. Interactions of 1 and 2 with polyuridylic acid (Poly (U)) were also examined by Tm, mixing curves, UV and CD spectra. Both the dinucleoside isomers 1 and 2 formed a complex of 1 : 2 stoichiometry with poly(U), which was much more stable than that of the corresponding ApA isomer  相似文献   

13.
Novel inhibitors of TGF-β1 and activin A signalling based on a 2-aryl-4-(3-(pyridin-2-yl)-1H-pyrazol-4-yl)pyridine pharmacophore have been synthesised. Compounds containing phenyl or aromatic nitrogen heterocycle substituents inhibited both types of signalling with HEK-293T cells in culture, with a selectivity preference for TGF-β1. Synthetic compounds containing pyridin-3-yl, pyrazol-4-yl, pyrazol-1-yl or 1H-imidazoyl-1-yl substituents exhibited structural and functional attributes suitable for further investigation related to the development of more potent TGF-β inhibitors.  相似文献   

14.
The formation of a complex between (1 → 3)-β-d-glucan and congo red in dilute alkaline solutions (0.1 and 0.15 m sodium hydroxide) where the glucan takes an ordered conformation was studied by measuring visible absorption spectra of the solutions at various temperatures between 15 and 35°C. The average number of the glucose residues forming the binding site to accommodate one dye molecule decreased with increasing temperature or decreasing alkaline concentration, suggesting possible conformational changes of the glucan chain. The complex formation constant, K, increased with increasing temperature, and thermodynamical parameters, ?H° and ?S°, for the complex formation in 0.1 m and 0.15 m aqueous NaOH solutions were obtained at 25°C to be 14 kcal/mol and 77 e.u. (0.1 m), and 12 kcal/mol and 68 e.u. (0.15 m), respectively. These results indicate that the driving force for the complex formation is entropic in nature stemming from the decrease of “iceberg formation”.  相似文献   

15.
A series of 1-substituted-3(5)-(6-methylpyridin-2-yl)-4-(quinolin-6-yl)pyrazoles 14a-e, 15a-e, 17a-c, and 18a-d have been synthesized and evaluated for their ALK5 inhibitory activity in an enzyme assay and in a cell-based luciferase reporter assay. The 6-quinolinyl pyrazole analogue 14b inhibited ALK5 phosphorylation with IC(50) value of 0.022 μM and showed 84% inhibition at 0.1 μM in a luciferase reporter assay using HaCaT cells permanently transfected with p3TP-luc reporter construct.  相似文献   

16.
An atom-efficient and stereoselective synthesis has been developed for the preparation of α-2H-labelled (S)-α-amino acids, starting from a novel chiral diketopiperazine scaffold. Efficient mono-alkylation of the chiral template afforded the (S)-substituted adducts with the nature of the electrophile significantly effecting the stereochemical outcome. Subsequent alkylation was totally selective producing the 1,4-cis adduct as the sole diastereoisomer. The deprotection was carried out using cerium ammonium nitrate followed by acid hydrolysis affording the enantipure α-amino acids.  相似文献   

17.
Among a library of 70 azoles, 8 indole derivatives substituted in the 2-, 3- or 5- position with an azolylmethyl or α-azolylbenzyl chain were evaluated for retinoic acid (RA) metabolism inhibitory activity. The most active inhibitors identified in this study were 5-bromo-1-ethyl-3-methyl-2-[(phenyl)(1H-1,2,4-triazol-1-yl)methyl]-1H-indole (3) (68.9% inhibition) and 5-bromo-1-ethyl-2-[(4-fluorophenyl)(1H-1,2,4-triazol-1-yl)methyl]-3-methyl-1H-indole (6) (60.4% inhibition). At the same concentration (100 μM) ketoconazole exerted similar inhibitory effect (70% inhibition).  相似文献   

18.
19.
20.
Acetyl-CoA carboxylases (ACCs) catalyze a critical step in de novo lipogenesis, and are considered as promising targets for treatment of obesity, dyslipidemia and type 2 diabetes mellitus. On the other hand, peroxisome proliferator-activated receptors (PPARs) are well-established therapeutic targets for these metabolic syndrome-related diseases. Therefore, we considered that dual modulators of ACC and PPARs would be promising candidates as therapeutic agents. Here, we designed a series of acetamides based on the molecular similarity between ACC inhibitors and PPAR agonists. Screening of the synthesized compounds identified N-(1-(3-(4-phenoxyphenyl)-1,2,4-oxadiazol-5-yl)ethyl)acetamides as novel ACC2 inhibitors with PPARα/PPARδ dual agonistic activity. Structure–activity relationship studies and further structural elaboration afforded compounds with distinct activity profiles. Our findings should be helpful for the discovery of candidate agents with an appropriate balance of ACC-inhibitory and PPAR-activating activities for therapeutic lipid control.  相似文献   

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