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1.
A novel series of cis-3,4-diphenylpyrrolidines were designed as RORγt inverse agonists based on the binding conformation of previously reported bicyclic sulfonamide 1. Preliminary synthesis and structure–activity relationship (SAR) study established (3S,4S)-3-methyl-3-(4-fluorophenyl)-4-(4-(1,1,1,3,3,3-hexafluoro-2-hydroxyprop-2-yl)phenyl)pyrrolidine as the most effective scaffold. Subsequent SAR optimization led to identification of a piperidinyl carboxamide 31, which was potent against RORγt (EC50 of 61 nM in an inverse agonist assay), selective relative to RORα, RORβ, LXRα and LXRβ, and stable in human and mouse liver microsomes. Furthermore, compound 31 exhibited considerably lower PXR Ymax (46%) and emerged as a promising lead. The binding mode of the diphenylpyrrolidine series was established with an X-ray co-crystal structure of 10A/RORγt.  相似文献   

2.
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   

3.
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   

4.
The patterns of incorporation of d-[G-14C]shikimate and variously labelled 14C-4-(2′-carboxy-phenyl)-4-oxobutyrate into the naphthoquinone nucleus of phylloquinone by maize shoots have been investigated. The results show that (a) the alicyclic ring and C-7 of shikimate give rise to Ring A and either C-1 or C-4, and (b) the phenyl ring, 2′-carboxy and C-4, and C-2 and -3 of 4-(2′-carboxyphenyl)-4-oxobutyrate give rise to Ring A, C-1 and -4 and C-2 and -3. Radioactivity from α-[1-14C]naphthol, 1,4-[1,4-14C]naphthoquinone and [Me-14C]menadione is not incorporated into phylloquinone to any significant extent.  相似文献   

5.
For use as the internal standards in a quantitative analysis of natural jasmonic acid (JA) and methyl jasmonate (JAMe) by gas chromatography-mass spectrometry-selected ion monitoring, (±)-2-(2,3–2H2)JA and its methyl ester, (±)-2-(2,3–2H2)JAMe, were efficiently prepared from 2-(2–pentyl)-2-cyclopentenone through catalytic semi-deuteriogenation of acetylenic intermediates with deuterium gas in pyridine.  相似文献   

6.
Russian Journal of Bioorganic Chemistry - The synthesis of amphiphilic cationic β-cyclodextrin derivatives that contain the residues of some pharmacologically important acids have been...  相似文献   

7.
《Carbohydrate research》1988,172(1):11-25
Benzyl-3-O-benzyl-2-benzyloxycarbonylamino-6-O-[2-benzyloxycarbonyl-amino-2-deoxy-3,4-O-(tetraisopropyldisiloxane-1,3-diyl)- β-d-glucopyranosyl]-2-deoxy-α-d-glucopyranoside was coupled with methyl (4,5,7,8-tetra-O-acetyl-3-deoxy-α-d-manno-2-octulopyranosyl bromide)onate (13) to yield the α-glycosidically linked trisaccharide. After deacetylation and selective introduction of a second 7′,8′-O-tetraisopropyldisiloxane group, a further glycosidation reaction with 13 led regioselectively to the tetrasaccharide benzyl O-[methyl (4,5,7,8-tetra-O-acetyl-3-deoxy-α-d-manno-2-octulopyranosyl)onate]-(2→4)-O-{methyl [3-deoxy-7,8-O-(tetraisopropyldisiloxane-1,3-diyl)-α-d-manno-2-octulopyranosyl]-onate}-(2→6)-O- [2-benzyloxycarbonylamino-2-deoxy-3,4-O-(tetraisopropyldisiloxane-1,3-diyl)-β-d-glucopyranosyl]- (1→6)-3-O-benzyl-2-benzyloxycarbonyl-amino-2-deoxy-α-d-glucopyranoside. A series of deblocking steps gave O-(3-deoxy-α-d-manno-2-octulopyranosylonic acid)-(2→4)-O-(3-deoxy-α-d-manno-2-octulopyranosylonic acid)- (2→6)-O-(2-amino-2-deoxy-β-d-glucopyranosyl)-(1→6)-2-amino-2-deoxy-d-glucopyranose which was identical with a tetrasaccharide that had been isolated by hydrazinolysis of the lipopolysaccharide from Salmonella minnesota R 595. Hence, synthetic proof is provided for the linkages in this part of the inner core region of lipopolysaccharides.  相似文献   

8.
The design of a new clinical candidate histamine-H(3) receptor antagonist for the potential treatment of excessive daytime sleepiness (EDS) is described. Phenethyl-R-2-methylpyrrolidine containing biphenylsulfonamide compounds were modified by replacement of the sulfonamide linkage with a sulfone. One compound from this series, 2j (APD916) increased wakefulness in rodents as measured by polysomnography with a duration of effect consistent with its pharmacokinetic properties. The identification of a suitable salt form of 2j allowed it to be selected for further development.  相似文献   

9.
We studied hydrated calcium oxalate and its ions at the restricted Hartree–Fock RHF/6-31G* level of theory. Performing a configurational search seems to improve the fit of the HF/6-31G* level to experimental data. The first solvation shell of calcium oxalate contains 13 water molecules, while the first solvation shell of oxalate ion is formed by 14 water molecules. The first solvation shell of Ca(II) is formed by six water molecules, while the second shell contains five. At 298.15 K, we estimate the asymptotic limits (infinite dilution) of the total standard enthalpies of hydration for Ca(II), oxalate ion and calcium oxalate as ?480.78, –302.78 and –312.73 kcal mol?1, resp. The dissociation of hydrated calcium oxalate is an endothermic process with an asymptotic limit of +470.84 kcal mol?1.
Figure
CaC2O4(H2O)16 and C2O4 2-(H2O)14  相似文献   

10.
4-(2′-Carboxyphenyl)-4-oxobutyric acid (6) has been detected in cuttings of Impatiens balsamina. It is labelled under conditions where activity from U-14C-glutamate is incorporated effectively into lawsone (1). 3-(2′-Carboxyphenyl)-3-oxopropionic acid (7) has also been encountered in the cuttings.  相似文献   

11.
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   

12.
岑文  孔维维  郑鹏  化文平 《广西植物》2015,35(5):755-760
龙胆苦苷(gentiopicroside)等裂环烯醚萜苷类化合物是中药秦艽中主要的有效成分,属于萜类化合物的衍生物,1-羟基-2-甲基-2-(E)-丁烯基-4-焦磷酸还原酶(1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate reductase,HDR)是植物萜类物质合成的关键酶之一。该研究在实验室高通量测序的基础上,采用RT-PCR方法克隆了秦艽HDR基因(即Gm HDR基因),利用生物信息学的方法分析了Gm HDR编码氨基酸序列的理化性质、信号肽、转运肽、亚细胞定位、保守结构域和高级结构等特征,并采用实时定量PCR分析了HDR的表达模式。结果表明:秦艽Gm HDR基因包含一个完整的长1 392 bp的ORF框,编码463个氨基酸;Gm HDR与萝芙木、艾菊等植物HDR蛋白具有很高的一致性(≥84%),无跨膜结构域,有叶绿体转运肽等结构,主要定位于叶绿体中。实时定量PCR结果显示,Gm HDR基因在秦艽的花中进行表达量高,在叶、茎和根等部位表达较低。Gm HDR在序列上与其他植物的HDR蛋白序列特征上存在很大的相似性;Gm HDR基因主要在秦艽花中表达,可能主要参与花中萜类物质的合成。该研究结果可为今后研究秦艽环烯醚萜类化合物的生物合成机制提供依据。  相似文献   

13.
[2–14C]-(2Z,4E)-γ-Ionylideneethanol and [2–14C]-(2Z,4E)-γ-ionylideneacetic acid were converted by Cercospora cruenta to [2–14C]-(2Z,4E)-1′,4′-dihydroxy-γ-ionylideneacetic acid and [2-14C]-(2Z,4E)-4′-hydroxy-γ-ionylideneacetic acid, which are intermediates of ABA biosynthesis in C. cruenta.  相似文献   

14.
The optimum geometries and binding energies of the complexes formed by AMPA and Kainic acid, as well as their anions with tyrosine, proline and some tripeptides are investigated with quantum chemical calculations (HF/6-31G**). It was found that receptors featuring the Tyr-Ala-Pro sequence exhibit stronger binding energies to the substrates than the Tyr-Ser-Pro and Tyr-Ser-Ser. As expected, the anions are more bound than the neutral species. This work can lead to investigations on the effect of AMPA receptors mutations on the brain functions, possibly related to criminal tendencies.  相似文献   

15.
Pd(II), Cu(II) and Zn(II) complexes (13) based on 4′-(4-(2-(piperidin-1-yl)ethoxy)phenyl)-2,2′:6′,2″-terpyridine were synthesized and characterized by UV, IR, NMR, EPR, HRMS, elemental analyses, and molar conductivity measurements. The cytotoxicity of these complexes against HL-60, BGC-823, KB, Bel-7402, A549, Hela, K562 and MCF-7 cell lines in vitro was measured by MTT method. The DNA binding property of the complexes was evaluated by UV, fluorescence, CD spectroscopies and thermal denaturation. The cytotoxicity of complexes 1 and 3 against all the tested cell lines is better than that of cisplatin. Complexes 1 and 2 exhibit 7- and 4-folds higher cytotoxicity than cisplatin against Bel-7402 cell line. Complex 3 displays the highest cytotoxicity against all the cell lines tested, and shows 7-, 14-, 8-, 11- and 8-folds higher cytotoxicity than cisplatin against Bel-7402, A549, Hela, K562 and MCF-7 cell lines. The complexes bind to DNA via intercalation mode and complex 3 stabilizes the G-quadruplex. The results reveal that all the complexes display high cytotoxicity against all the tested cancer cell lines, and complex 3 is selective for G-quadruplex over duplex DNA.  相似文献   

16.
A series of galactose-derived aryl enones were synthesised and screened against Mycobacterium tuberculosis H37Rv. Preliminary results were promising with MIC values in the range 1.56-12.5 μg/mL.  相似文献   

17.
4-羟基-3-甲基-2-(E)-丁烯基-4-磷酸还原酶(4-hydroxy-3-methyl-2-(E)-butenyl-4-diphosphatereductase,HDR)是异戊烯基焦磷酸合成途径之一甲基赤藓糖磷酸(methylerythritol phosphate,MEP)途径中的最后一个酶,催化4-羟基-3-甲基-(2E)-丁烯基-4-磷酸生成异戊烯基焦磷酸.根据植物HDR的同源序列设计引物,通过RT-PCR结合RACE的方法在橡胶树中获得了与其相应的HDR基因,命名为HbHDR.序列分析表明HbHDR长1 627 bp,编码462个氨基酸,属于LYTB家族,该氨基酸序列与烟草、长春花、胡黄连、拟南芥、银杏和火炬松的HDR同源性为79.1%、78.4%、76.5%、75.3%、72.2%和70.9%.半定量RT-PCR结果显示,乙烯诱导胶乳HbHDR的表达.  相似文献   

18.
The effect of tripropyltin chloride (TPT) on transport systems in E. coli was investigated. The inhibition on uptakes of 14C-l-leucine, l-proline, adenine and methyl-(α-d-gluco)pyrano-side (α-methylglucoside) by TPT was examined. The active uptake of l-leucine which utilized ATP molecule as an energy source was 100% inhibited at the concentration of 10 µg/ml TPT. On the other hand, the uptake of l-proline which was generated by an “energied” membrane state of the cells was inhibited only 40% at the same concentration of TPT. α-Methylglucoside uptake was scarcely inhibited. Adenine uptake was intensely inhibited at 20 µg/ml TPT. The effect of the delayed addition of TPT on transport systems was also examined. l-Leucine incorporated into cells was completely released from cells by TPT. Leucine binding protein (LBP) was prepared from E. coli cells and the effect of TPT on LBP activity was examined. TPT scarcely inhibited LBP activity.  相似文献   

19.
20.
Abstract

Phase-transfer catalysis of pyrrolo[2,3-d]pyrimidine 4a with the halogenose 5 yields the anomers 6a and 7a. Deprotection with boron trichloride gives the chloro nucleosides 6b and 7b, which are converted into the potential anticytokinin 2 and its α-anomer 3.  相似文献   

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