7,965 results match your criteria conformation pyridine

Advantages of Organic Halogen Bonding for Halide Recognition.

Supramol Chem 2016 11;28(7-8):665-672. Epub 2015 Dec 11.

Department of Chemistry and Biochemistry, University of Montana, Missoula MT, USA.

The study of hydrogen bonding organocatalysis is rapidly expanding. Much research has been directed at making catalysts more active and selective, with less attention on fundamental design strategies. This study systematically increases steric hindrance at the active site of pH switchable urea organocatalysts. Read More

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December 2015

Conformational and rheological properties of bacterial cellulose sulfate.

Int J Biol Macromol 2021 Jun 2. Epub 2021 Jun 2.

School of Stomatology, Lanzhou University, Lanzhou 730000, China.

In this study, a water-soluble bacterial cellulose sulfate (BCS) was prepared with SO/pyridine (Py) complex in a LiCl/dimethylacetamide (DMAc) homogeneous solution system using bacterial cellulose (BC). The structural study showed that the value for the degrees of substitution of BCS was 1.23. Read More

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Crystal structure and Hirshfeld surface analysis of 6-amino-8-(2,6-di-chloro-phen-yl)-1,3,4,8-tetra-hydro-2-pyrido[1,2-]pyrimidine-7,9-dicarbo-nitrile.

Acta Crystallogr E Crystallogr Commun 2021 May 9;77(Pt 5):516-521. Epub 2021 Apr 9.

Department of Chemistry, Baku State University, Z. Khalilov str. 23, Az, 1148 Baku, Azerbaijan.

In the mol-ecular structure of the title compound, CHClN, the 1,4-di-hydro-pyridine ring of the 1,3,4,8-tetra-hydro-2-pyrido[1,2-]pyrimidine ring system adopts a screw-boat conformation, while the 1,3-diazinane ring is puckered. In the crystal, inter-molecular N-H⋯N and C-H⋯N hydrogen bonds form mol-ecular sheets parallel to the (110) and (10) planes, crossing each other. Adjacent mol-ecules are further linked by C-H⋯π inter-actions, which form zigzag chains propagating parallel to [100]. Read More

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Crystal structure and Hirshfeld surface analysis of 6-amino-8-phenyl-1,3,4,8-tetra-hydro-2-pyrido[1,2-]pyrimidine-7,9-dicarbo-nitrile.

Acta Crystallogr E Crystallogr Commun 2021 May 9;77(Pt 5):512-515. Epub 2021 Apr 9.

Department of Chemistry, Baku State University, Z. Khalilov str. 23, Az, 1148 Baku, Azerbaijan.

In the title compound, CHN, the 1,4-di-hydro-pyridine ring has a shallow boat conformation, while the 1,3-diazinane ring adopts an envelope conformation. In the crystal, pairwise N-H⋯N hydrogen bonds generate centrosymmetric dimers featuring (12) motifs and C-H⋯N contacts connect these dimers to form double layers lying parallel to (001). Weak C-H⋯π and N-H⋯π inter-actions help to consolidate the double layers and van der Waals inter-actions occur between layers. Read More

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Crystal structure and Hirshfeld surface analysis of ethyl 2-[9-(2-hy-droxy-phen-yl)-3,3,6,6-tetra-methyl-1,8-dioxo-2,3,4,4a,5,6,7,8a,9,9a,10,10a-dodeca-hydro-acridin-10-yl]acetate.

Acta Crystallogr E Crystallogr Commun 2021 Mar 12;77(Pt 3):247-250. Epub 2021 Feb 12.

Faculty of Science, Department of Bio Chemistry, Beni Suef University, Beni Suef, Egypt.

In the title compound, CHNO, a 3,3,6,6-tetra-methyl-tetra-hydro-acridine-1,8-dione ring system carries an ethyl acetate substituent on the acridine N atom and an -hy-droxy-phenyl ring on the central methine C atom of the di-hydro-pyridine ring. The benzene ring is inclined to the acridine ring system at an angle of 80.45 (7)° and this conformation is stabilized by an intra-molecular O-H⋯O hydrogen bond between the hy-droxy substituent on the benzene ring and one of the carbonyl groups of the acridinedione unit. Read More

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High-resolution view of HIV-1 reverse transcriptase initiation complexes and inhibition by NNRTI drugs.

Nat Commun 2021 05 4;12(1):2500. Epub 2021 May 4.

Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA.

Reverse transcription of the HIV-1 viral RNA genome (vRNA) is an integral step in virus replication. Upon viral entry, HIV-1 reverse transcriptase (RT) initiates from a host tRNA primer bound to the vRNA genome and is the target of key antivirals, such as non-nucleoside reverse transcriptase inhibitors (NNRTIs). Initiation proceeds slowly with discrete pausing events along the vRNA template. Read More

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Permeant fluorescent probes visualize the activation of SARM1 and uncover an anti-neurodegenerative drug candidate.

Elife 2021 May 4;10. Epub 2021 May 4.

State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, China.

SARM1 regulates axonal degeneration through its NAD-metabolizing activity and is a drug target for neurodegenerative disorders. We designed and synthesized fluorescent conjugates of styryl derivative with pyridine to serve as substrates of SARM1, which exhibited large red shifts after conversion. With the conjugates, SARM1 activation was visualized in live cells following elevation of endogenous NMN or treatment with a cell-permeant NMN-analog. Read More

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Crystal structures of 1-(4-chloro-phen-yl)-4-(4-methyl-phen-yl)-2,5-dioxo-1,2,5,6,7,8-hexa-hydro-quinoline-3-carb-oxy-lic acid and 4-(4-meth-oxy-phen-yl)-1-(4-methyl-phen-yl)-2,5-dioxo-1,2,5,6,7,8-hexa-hydro-quinoline-3-carbo-nitrile.

Acta Crystallogr E Crystallogr Commun 2021 Apr 5;77(Pt 4):351-355. Epub 2021 Mar 5.

Department of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA.

In the title compounds CHClNO [, namely 1-(4-chloro-phen-yl)-4-(4-methyl-phen-yl)-3,8-dioxo-1,2,5,6,7,8-hexa-hydro-quine-3-carb-oxy-lic acid] and CHNO [, namely 4-(4-meth-oxy-phen-yl)-1-(4-methyl-phen-yl)-2,5-dioxo-1,2,5,6,7,8-hexa-hydro-quinoline-3-carbo-nitrile], each of the cyclo-hexene and di-hydro-pyridine rings of the 1,2,5,6,7,8-hexa-hydro-quinoline moieties adopts a twisted-boat conformation. The asymmetric units of both compounds and consist of two independent mol-ecules ( and ). In , three carbon atoms of the cyclo-hexene ring are disordered over two sets of sites in a 0. Read More

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Synthesis, Characterization and Biological Evaluation of New 3,5-Disubstituted-Pyrazoline Derivatives as Potential Anti- H37Ra Compounds.

Molecules 2021 Apr 5;26(7). Epub 2021 Apr 5.

School of Chemical Sciences, Universiti Sains Malaysia, Minden, Penang 11800, Malaysia.

A total of fourteen pyrazoline derivatives were synthesized through cyclo-condensation reactions by chalcone derivatives with different types of semicarbazide. These compounds were characterized by IR, 1D-NMR (H, C and Distortionless Enhancement by Polarization Transfer - DEPT-135) and 2D-NMR (COSY, HSQC and HMBC) as well as mass spectroscopy analysis (HRMS). The synthesized compounds were tested for their antituberculosis activity against H37Ra in vitro. Read More

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2,3-Dihydroferroceno[3,4]pyrrolo[2,1-b]thiazol-5(8b)-ones: Synthesis, Structure and DFT Study on the Mechanism of Chemo- and Diastereoslective Annulations of ()-2-Formylferrocenecarbonyl Fluoride and ()-2-Formylferrocenecarboxylic Acid.

Molecules 2021 Mar 5;26(5). Epub 2021 Mar 5.

Department of Organic Chemistry, Eötvös Loránd University (ELTE), Pázmány P. sétány 1/A, H-1117 Budapest, Hungary.

By means of the annulation of easy-to-handle yet sufficiently reactive ()-2-formylferrocenecar- bonyl fluoride with the hydrochlorides of cysteamine and the methyl esters of enentiomer cysteines conducted in dichloromethane at room temperature in the presence of pyridine, the first members of 2,3-dihydroferroceno[3,4]pyrrolo[2,1-b]thiazol-5(8)-ones with the elements of planar- and central chirality were prepared as single enantiomers. An atom economic procedure was also elaborated for the synthesis of these organometallic heterocycles directly exploring ()-2-formylferrocenecarboxylic acid in situ activated by CDI and TFA, sequentially added to the reaction mixture. The relative and consequently, the absolute, configuration of the isolated diastereomers was determined by NMR measurements supported by DFT structural optimization. Read More

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Amyloid-Beta Induces Different Expression Pattern of Tissue Transglutaminase and Its Isoforms on Olfactory Ensheathing Cells: Modulatory Effect of Indicaxanthin.

Int J Mol Sci 2021 Mar 25;22(7). Epub 2021 Mar 25.

Institute for Biomedical Research and Innovation (IRIB), National Research Council, 95126 Catania, Italy.

Herein, we assessed the effect of full native peptide of amyloid-beta (Aβ) (1-42) and its fragments (25-35 and 35-25) on tissue transglutaminase (TG2) and its isoforms (TG2-Long and TG2-Short) expression levels on olfactory ensheathing cells (OECs). Vimentin and glial fibrillary acid protein (GFAP) were also studied. The effect of the pre-treatment with indicaxanthin from Opuntia ficus-indica fruit on TG2 expression levels and its isoforms, cell viability, total reactive oxygen species (ROS), superoxide anion (O), and apoptotic pathway activation was assessed. Read More

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The diverse functionality of NQO1 and its roles in redox control.

Redox Biol 2021 May 20;41:101950. Epub 2021 Mar 20.

Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.

In this review, we summarize the multiple functions of NQO1, its established roles in redox processes and potential roles in redox control that are currently emerging. NQO1 has attracted interest due to its roles in cell defense and marked inducibility during cellular stress. Exogenous substrates for NQO1 include many xenobiotic quinones. Read More

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Can Serendipity Still Hold Any Surprises in the Coordination Chemistry of Mixed-Donor Macrocyclic Ligands? The Case Study of Pyridine-Containing 12-Membered Macrocycles and Platinum Group Metal Ions Pd, Pt, and Rh.

Molecules 2021 Feb 27;26(5). Epub 2021 Feb 27.

Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Cagliari, S.S. 554 bivio per Sestu, 09042 Monserrato (Cagliari), Italy.

This study investigates the coordination chemistry of the tetradentate pyridine-containing 12-membered macrocycles - towards Platinum Group metal ions Pd, Pt, and Rh. The reactions between the chloride salts of these metal ions and the three ligands in MeCN/HO or MeOH/HO (1:1 /) are shown, and the isolated solid compounds are characterized, where possible, by mass spectroscopy and H- and C-NMR spectroscopic measurements. Structural characterization of the 1:1 metal-to-ligand complexes [Pd()Cl][PdCl], [Pt()Cl](BF), [Rh()Cl](PF), and [Rh()Cl](BF)·MeCN shows the coordinated macrocyclic ligands adopting a folded conformation, and occupying four coordination sites of a distorted square-based pyramidal and octahedral coordination environment for the Pd/Pt, and Rh complexes, respectively. Read More

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February 2021

Structural and Thermodynamic Analysis of the Resistance Development to Pimodivir (VX-787), the Clinical Inhibitor of Cap Binding to PB2 Subunit of Influenza A Polymerase.

Molecules 2021 Feb 14;26(4). Epub 2021 Feb 14.

Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Gilead Sciences and IOCB Research Center, Flemingovo n. 2, 16610 Prague 6, Czech Republic.

Influenza A virus (IAV) encodes a polymerase composed of three subunits: PA, with endonuclease activity, PB1 with polymerase activity and PB2 with host RNA five-prime cap binding site. Their cooperation and stepwise activation include a process called cap-snatching, which is a crucial step in the IAV life cycle. Reproduction of IAV can be blocked by disrupting the interaction between the PB2 domain and the five-prime cap. Read More

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February 2021

Versatile Reactivity of Mn Complexes in Reactions with N-Donor Heterocycles: Metamorphosis of Labile Homometallic Pivalates vs. Assembling of Endurable Heterometallic Acetates.

Molecules 2021 Feb 15;26(4). Epub 2021 Feb 15.

N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP-1, Russia.

Reaction of 2,2'-bipyridine (2,2'-bipy) or 1,10-phenantroline (phen) with [Mn(Piv)(EtOH)] led to the formation of binuclear complexes [Mn(Piv)L] (L = 2,2'-bipy (), phen (); Piv is the anion of pivalic acid). Oxidation of or by air oxygen resulted in the formation of tetranuclear Mn complexes [MnO(Piv)L] (L = 2,2'-bipy (), phen ()). The hexanuclear complex [Mn(OH)(Piv)(pym)] () was formed in the reaction of [Mn(Piv)(EtOH)] with pyrimidine (pym), while oxidation of produced the coordination polymer [MnO(Piv)(pym)] (). Read More

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February 2021

Influence of ligand substituent conformation on the spin state of an iron(II)/di(pyrazol-1-yl)pyridine complex.

Dalton Trans 2021 Mar;50(10):3464-3467

School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, UK LS2 9JT.

The temperature of the solution-phase spin-crossover equilibrium in iron(ii) complexes of 4-alkylsulfanyl-2,6-di{pyrazol-1-yl}pyridine (bppSR) complexes depends strongly on the alkylsulfanyl substituent. DFT calculations imply this reflects the conformation of the alkylsulfanyl groups, which lie perpendicular to the heterocyclic ligand donors in [Fe(bppStBu)2]2+ but are oriented co-planar with the ligand core for smaller SR substituents. Read More

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Structure-guided insights into heterocyclic ring-cleavage catalysis of the non-heme Fe (II) dioxygenase NicX.

Nat Commun 2021 02 26;12(1):1301. Epub 2021 Feb 26.

State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China.

Biodegradation of aromatic and heterocyclic compounds requires an oxidative ring cleavage enzymatic step. Extensive biochemical research has yielded mechanistic insights about catabolism of aromatic substrates; yet much less is known about the reaction mechanisms underlying the cleavage of heterocyclic compounds such as pyridine-ring-containing ones like 2,5-hydroxy-pyridine (DHP). 2,5-Dihydroxypyridine dioxygenase (NicX) from Pseudomonas putida KT2440 uses a mononuclear nonheme Fe(II) to catalyze the oxidative pyridine ring cleavage reaction by transforming DHP into N-formylmaleamic acid (NFM). Read More

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February 2021

Crystal structure and Hirshfeld surface analysis of the hydro-chloride salt of 8-{4-[(6-phenyl-pyridin-3-yl)meth-yl]piperazin-1-yl}-3,4-di-hydro-quinolin-2(1)-one.

Acta Crystallogr E Crystallogr Commun 2021 Feb 29;77(Pt 2):208-212. Epub 2021 Jan 29.

Institute of Physics, University of Neuchâtel, rue Emile-Argand 11, CH-2000 Neuchâtel, Switzerland.

The amine 8-{4-[(6-phenyl-pyridin-3-yl)meth-yl]piperazin-1-yl}-3,4-di-hydro-quinolin-2(1)-one was crystallized as the hydro-chloride salt, 4-(2-oxo-1,2,3,4-tetra-hydro-quinolin-8-yl)-1-[(6-phenyl-pyridin-3-yl)meth-yl]piperazin-1-ium chloride, CHN·Cl (). The conformation of the organic cation is half-moon in shape enclosing the chloride anion. The piperidine ring of the 3,4-di-hydro-quinolin-2(1)-one moiety has a screw-boat conformation, while the piperazine ring has a chair conformation. Read More

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February 2021

Crystal structure and Hirshfeld surface analysis of 3-amino-1-oxo-2,6,8-triphenyl-1,2,7,8-tetra-hydro-iso-quinoline-4-carbo-nitrile.

Acta Crystallogr E Crystallogr Commun 2021 Feb 29;77(Pt 2):195-199. Epub 2021 Jan 29.

Department of Chemistry, Baku State University, Z. Khalilov str. 23, Az, 1148 Baku, Azerbaijan.

In the title compound, CHNO, the 1,2-di-hydro-pyridine ring of the 1,2,7,8-tetra-hydro-iso-quinoline ring system is planar as expected, while the cyclo-hexa-1,3-diene ring has a twist-boat conformation, with Cremer-Pople parameters = 0.367 (2) A, θ = 117.3 (3)° and φ = 327. Read More

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February 2021

Design of pyrido[2,3-d]pyrimidin-7-one inhibitors of receptor interacting protein kinase-2 (RIPK2) and nucleotide-binding oligomerization domain (NOD) cell signaling.

Eur J Med Chem 2021 Apr 3;215:113252. Epub 2021 Feb 3.

Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Health Building 2, Houston, TX, 77204, USA. Electronic address:

Receptor interacting protein kinase-2 (RIPK2) is an enzyme involved in the transduction of pro-inflammatory nucleotide-binding oligomerization domain (NOD) cell signaling, a pathway implicated in numerous chronic inflammatory conditions. Herein, a pyrido[2,3-d]pyrimidin-7-one based class of RIPK2 kinase and NOD2 cell signaling inhibitors is described. For example, 33 (e. Read More

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Dual Trapping of a Metastable Planarized Triarylborane π-System Based on Folding and Lewis Acid-Base Complexation for Seeded Polymerization.

J Am Chem Soc 2021 Feb 10;143(7):2953-2961. Epub 2021 Feb 10.

Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo, Chikusa, Nagoya 464-8601, Japan.

We report the kinetically controlled supramolecular polymerization of boron-containing π-conjugated molecules, which was enabled by a seeding method based on dual trapping of a metastable state by synergistic intramolecular hydrogen bonding and Lewis acid-based complexation. Planarized triarylborane-based , which bears a diamide chain with chiral alkyl groups, was synthesized. Upon cooling, the solution of monomer afforded a supramolecular polymerization in a cooperative manner to form helical supramolecular nanostructures with intense J-type aggregate emission. Read More

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February 2021

Impact of the Metal Center and Leaving Group on the Anticancer Activity of Organometallic Complexes of Pyridine-2-carbothioamide.

Molecules 2021 Feb 5;26(4). Epub 2021 Feb 5.

School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.

Ru(cym)Cl (cym = η--cymene) complexes of pyridinecarbothioamides have shown potential for development as orally active anticancer metallodrugs, underlined by their high selectivity towards plectin as the molecular target. In order to investigate the impact of the metal center on the anticancer activity and their physicochemical properties, the Os(cym), Rh- and Ir(Cp*) (Cp* = pentamethylcyclopentadienyl) analogues of the most promising and orally active compound plecstatin were prepared and characterized by spectroscopic techniques and X-ray diffraction analysis. Dissolution in aqueous medium results in quick ligand exchange reactions; however, over time no further changes in the H NMR spectra were observed. Read More

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February 2021

Molecular Recognition of Imidazole Derivatives by Co(III)-Porphyrinsin Phosphate Buffer (pH = 7.4) and Cetylpyridinium Chloride Containing Solutions.

Molecules 2021 Feb 6;26(4). Epub 2021 Feb 6.

G.A. Krestov Institute of Solution Chemistry of the Russian Academy of Sciences, Akademicheskayast. 1, Ivanovo 153045, Russia.

Bymeans of spectrophotometric titration and NMR spectroscopy, the selective binding ability ofthe Co(III)-5,15-bis-(3-hydroxyphenyl)-10,20-bis-(4-sulfophenyl)porphyrin (Со(III)Р1) andCo(III)-5,15-bis-(2-hydroxyphenyl)-10,20-bis-(4-sulfophenyl)porphyrin (Со(III)Р2) towards imidazole derivatives of various nature (imidazole (L1), metronidazole (L2), and histamine (L3)) in phosphate buffer (pH 7.4) has been studied. It was found that in the case of L2, L3 the binding of the "first" ligand molecule by porphyrinatesCo(III)P1 and Co(III)P2 occurs with the formation of complexes with two binding sites (donor-acceptor bond at the center and hydrogen bond at the periphery of the macrocycle), while the "second" ligand molecule is added to the metalloporphyrin only due to the formation of the donor-acceptor bond at the macrocycle coordination center. Read More

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February 2021

Differential inhibition of human CYP2C8 and molecular docking interactions elicited by sorafenib and its major N-oxide metabolite.

Chem Biol Interact 2021 Apr 5;338:109401. Epub 2021 Feb 5.

Pharmacogenomics and Drug Development Group, Discipline of Pharmacology, School of Medical Sciences, Sydney Medical School, University of Sydney, NSW, 2006, Australia. Electronic address:

The tyrosine kinase inhibitor sorafenib (SOR) is being used increasingly in combination with other anticancer agents like paclitaxel, but this increases the potential for drug toxicity. SOR inhibits several human CYPs, including CYP2C8, which is a major enzyme in the elimination of oncology drugs like paclitaxel and imatinib. It has been reported that CYP2C8 inhibition by SOR in human liver microsomes is potentiated by NADPH-dependent biotransformation. Read More

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Structures of active-state orexin receptor 2 rationalize peptide and small-molecule agonist recognition and receptor activation.

Nat Commun 2021 02 5;12(1):815. Epub 2021 Feb 5.

Computational & Structural Chemistry, MRL, Merck & Co., Inc, West Point, PA, USA.

Narcolepsy type 1 (NT1) is a chronic neurological disorder that impairs the brain's ability to control sleep-wake cycles. Current therapies are limited to the management of symptoms with modest effectiveness and substantial adverse effects. Agonists of the orexin receptor 2 (OXR) have shown promise as novel therapeutics that directly target the pathophysiology of the disease. Read More

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February 2021

New Pharmaceutical Salts of Trazodone.

Molecules 2021 Feb 2;26(3). Epub 2021 Feb 2.

Department of Analytical Chemistry and Biomaterials, Faculty of Pharmacy, Medical University of Warsaw, Banacha 1, 02-093 Warsaw, Poland.

New pharmaceutically acceptable salts of trazodone (trazodone hydrogen bromide and trazodone 1-hydroxy-2-naphthonic acid) for the treatment of central nervous system disorders are synthesized and described. Although trazodone salts are poorly crystalline, single-crystal X-ray diffraction data for trazodone 1-hydroxy-2-naphthonic acid were collected and analyzed as well as compared to the previously described crystal structure of commercially available trazodone hydrochloride. The powder samples of all new salts were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and C solid-state nuclear magnetic resonance spectroscopy. Read More

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February 2021

A Fold Type II PLP-Dependent Enzyme from Functions as a Serine Synthase and Cysteine Synthase.

Biochemistry 2021 02 4;60(7):524-536. Epub 2021 Feb 4.

Department of Chemistry, University of British Columbia, Okanagan Campus, 3247 University Way, Kelowna, BC V1V 1V7, Canada.

Serine synthase (SS) from is a fold type II pyridoxal 5'-phosphate (PLP)-dependent enzyme that catalyzes the β-replacement of l-cysteine with water to form l-serine and HS. Herein, we show that SS can also function as a cysteine synthase, catalyzing the β-replacement of l-serine with bisulfide to produce l-cysteine and HO. The forward (serine synthase) and reverse (cysteine synthase) reactions occur with comparable turnover numbers and catalytic efficiencies for the amino acid substrate. Read More

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February 2021

Structural basis for ligand recognition of the neuropeptide Y Y receptor.

Nat Commun 2021 02 2;12(1):737. Epub 2021 Feb 2.

CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Pudong, Shanghai, 201203, China.

The human neuropeptide Y (NPY) Y receptor (YR) plays essential roles in food intake, bone formation and mood regulation, and has been considered an important drug target for obesity and anxiety. However, development of drugs targeting YR remains challenging with no success in clinical application yet. Here, we report the crystal structure of YR bound to a selective antagonist JNJ-31020028 at 2. Read More

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February 2021

Selective inhibition mechanism of nitroxoline to the BET family: Insight from molecular simulations.

Life Sci 2021 Apr 30;270:119141. Epub 2021 Jan 30.

College of Chemistry & Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China.

Although the proteins in bromodomain and extra-terminal domain (BET) family are promising therapy drug targets for numerous human diseases, the binding effectiveness is interfered by the competition from non-BET protein BRD9. In this study, molecular docking, molecular dynamics simulations, binding free energy calculations and per-residue energy decomposition methods were employed to clarify the selective inhibition mechanism of nitroxoline. The results showed that the different cavity volume of effective embedding inhibitor and the changes in conserved residues were associated with the significant higher selectivity of inhibitor nitroxoline for BET family than non-BET protein (BRD9). Read More

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Metal-Organic Cages with Missing Linker Defects.

Angew Chem Int Ed Engl 2021 Apr 5;60(16):9099-9105. Epub 2021 Mar 5.

School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai, 200240, China.

We present here the controlled synthesis of defective coordination cages by employing steric hindrance of organic linkers to manipulate coordination modes of the assembled metal ions. Three chiral 1,1'-bi-2-naphthol (BINOL) derived bis-tridentate ligands L -L with pyridine-2,6-dicarboxamides (pcam) chelating moieties are therefore designed and synthesized, among which L has a smaller steric hindrance on the coordinating sites relative to the other two linkers. Complexes of L and L with lanthanides afford the irregular Ln (L ) hexahedra with two missing edges and Ln (L ) tetrahedra with one missing edge, respectively, both of which contain a 1:1 mixture of Ln(pcam) and Ln(pcam) . Read More

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