Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
1.
Int J Mol Sci ; 25(7)2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38612782

RESUMEN

The synthesis and structural characterization of α-haloalkyl-substituted pyridinium-fused 1,2,4-selenadiazoles with various counterions is reported herein, demonstrating a strategy for directed supramolecular dimerization in the solid state. The compounds were obtained through a recently discovered 1,3-dipolar cycloaddition reaction between nitriles and bifunctional 2-pyridylselenyl reagents, and their structures were confirmed by the X-ray crystallography. α-Haloalkyl-substituted pyridinium-fused 1,2,4-selenadiazoles exclusively formed supramolecular dimers via four-center Se···N chalcogen bonding, supported by additional halogen bonding involving α-haloalkyl substituents. The introduction of halogens at the α-position of the substituent R in the selenadiazole core proved effective in promoting supramolecular dimerization, which was unaffected by variation of counterions. Additionally, the impact of cocrystallization with a classical halogen bond donor C6F3I3 on the supramolecular assembly was investigated. Non-covalent interactions were studied using density functional theory calculations and topological analysis of the electron density distribution, which indicated that all ChB, XB and HB interactions are purely non-covalent and attractive in nature. This study underscores the potential of halogen and chalcogen bonding in directing the self-assembly of functional supramolecular materials employing 1,2,4-selenadiazoles derived from recently discovered cycloaddition between nitriles and bifunctional 2-pyridylselenyl reagents.


Asunto(s)
Calcógenos , Halógenos , Dimerización , Reactivos de Enlaces Cruzados , Nitrilos
2.
Int J Mol Sci ; 23(12)2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35742815

RESUMEN

The synthesis and structural characterization of a series of supramolecular complexes of bicyclic cationic pyridine-fused 1,2,4-selenodiazoles with various anions is reported. The binding of trifluoroacetate, tetrachloroaurate, tetraphenylborate, perrhenate, and pertechnetate anions in the solid state is regarded. All the anions interact with selenodiazolium cations exclusively via a pair of "chelating" Se⋯O and H⋯O non-covalent interactions, which make them an attractive, novel, non-classical supramolecular recognition unit or a synthon. Trifluoroacetate salts were conveniently generated via novel oxidation reaction of 2,2'-dipyridyl diselenide with bis(trifluoroacetoxy)iodo)benzene in the presence of corresponding nitriles. Isolation and structural characterization of transient 2-pyridylselenyl trifluoroacetate was achieved. X-ray analysis has demonstrated that the latter forms dimers in the solid state featuring very short and strong Se⋯O and Se⋯N ChB contacts. 1,2,4-Selenodiazolium trifluoroacetates or halides show good solubility in water. In contrast, (AuCl4)-, (ReO4)-, or (TcO4)- derivatives immediately precipitate from aqueous solutions. Structural features of these supramolecular complexes in the solid state are discussed. The nature and energies of the non-covalent interactions in novel assembles were studied by the theoretical methods. To the best of our knowledge, this is the first study that regards perrhenate and pertechnetate as acceptors in ChB interactions. The results presented here will be useful for further developments in anion recognition and precipitation involving cationic 1,2,4-selenodiazoles.


Asunto(s)
Sales (Química) , Agua , Aniones/química , Cationes , Modelos Teóricos , Pertecnetato de Sodio Tc 99m , Ácido Trifluoroacético
3.
Molecules ; 27(3)2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35164294

RESUMEN

Chalcogenodiazoles have been intensively studied in recent years in the context of their supramolecular chemistry. In contrast, the newly discovered cationic 1,2,4-selenodiazole supramolecular building blocks, which can be obtained via coupling between 2-pyridylselenyl halides and nitriles, are virtually unexplored. A significant advantage of the latter is their facile structural tunability via the variation of nitriles, which could allow a fine tuning of their self-assembly in the solid state. Here, we explore the influence of the substituent (which derives from the nitrile) and counterions on the supramolecular assembly of cationic 1,2,4-selenodiazoles via chalcogen bonding.

4.
Molecules ; 27(16)2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-36014334

RESUMEN

New unsymmetrical monoterpenylhetaryl disulfides based on heterocyclic disulfides and monoterpene thiols were synthesized for the first time in 48-88% yields. Hydrolysis of disulfides with fragments of methyl esters of 2-mercaptonicotinic acid was carried out in 73-95% yields. The obtained compounds were evaluated for antioxidant, antibacterial, antifungal activity, cytotoxicity and mutagenicity.


Asunto(s)
Disulfuros , Compuestos de Sulfhidrilo , Antifúngicos/farmacología , Antioxidantes/farmacología , Ésteres , Mutágenos
5.
Molecules ; 27(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36144534

RESUMEN

A practical method for the synthesis of 2-selenoxo-1,2,3,4-tetrahydro-4-quinazolinone was reported. The latter compounds were found to undergo facile oxidation with H2O2 into corresponding diselenides. Novel organoselenium derivatives were characterized by the 1H, 77Se, and 13C NMR spectroscopies, high-resolution electrospray ionization mass spectrometry, IR, elemental analyses (C, H, N), and X-ray diffraction analysis for several of them. Novel heterocycles exhibited multiple remarkable chalcogen bonding (ChB) interactions in the solid state, which were studied theoretically.


Asunto(s)
Calcógenos , Peróxido de Hidrógeno , Ciclización , Compuestos de Organoselenio , Quinazolinonas , ortoaminobenzoatos
6.
Bioorg Med Chem Lett ; 29(17): 2443-2447, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31358465

RESUMEN

Type 2 diabetes mellitus is a complex metabolic disorder requiring polypharmacology approaches for effective treatment. Combinatorial library of fifteen new tricyclic benzimidazole derivatives have been designed and synthesized to combine fragments commonly found in allosteric AMPK activators and AT1 receptor antagonists. It was found that 2'-cyanobiphenyl serves as the pharmacophore of AMPK-activating activity, which also increases with the expansion of the external hydrogenated cycle. Also, pronounced antiplatelet activity is characteristic of the studied compounds. One of derivatives was identified as a potent inhibitor of the formation of advanced protein glycation end-products with reactive dicarbonyl scavenging activity. Two submicromolar AMPK activators 2b and 3b prevents inflammatory activation of murine macrophages. Along with good water solubility and synthetic availability, these results render biphenyl derivatives of fused benzimidazoles as a valuable starting point for the development of AMPK activators with multi-target antidiabetic activity.


Asunto(s)
Proteínas Quinasas Activadas por AMP/química , Bencimidazoles/química , Activadores de Enzimas/química , Hipoglucemiantes/química , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Bencimidazoles/farmacología , Bencimidazoles/uso terapéutico , Compuestos de Bifenilo/química , Bovinos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/patología , Evaluación Preclínica de Medicamentos , Activadores de Enzimas/farmacología , Activadores de Enzimas/uso terapéutico , Glicosilación/efectos de los fármacos , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Lipopolisacáridos/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Óxido Nítrico/metabolismo , Albúmina Sérica Bovina/metabolismo , Solubilidad , Relación Estructura-Actividad
7.
Bioorg Med Chem ; 27(9): 1804-1817, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30902399

RESUMEN

Glycogen synthase kinase 3ß (GSK-3ß) is a widely investigated molecular target for numerous diseases including Alzheimer's disease, cancer, and diabetes mellitus. Inhibition of GSK-3ß activity has become an attractive approach for treatment of diabetes and cancer. We report the discovery of novel GSK-3ß inhibitors of 3-arylidene-2-oxindole scaffold with promising activity. The most potent compound 3a inhibits GSK-3ß with IC50 4.19 nM. In a cell-based assay 3a shows no significant leucocyte toxicity at 10 µM and is moderately cytotoxic against A549 cells. Compound 3a demonstrated high antidiabetic efficacy in obese streptozotocin-treated rats improving glucose tolerance at a dose of 50 mg/kg body weight thus representing an interesting lead for further optimization.


Asunto(s)
Glucógeno Sintasa Quinasa 3 beta/antagonistas & inhibidores , Oxindoles/química , Inhibidores de Proteínas Quinasas/síntesis química , Células A549 , Animales , Sitios de Unión , Dominio Catalítico , Supervivencia Celular/efectos de los fármacos , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/tratamiento farmacológico , Prueba de Tolerancia a la Glucosa , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , Oxindoles/farmacología , Oxindoles/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Ratas , Relación Estructura-Actividad
8.
Beilstein J Org Chem ; 15: 1032-1045, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31164941

RESUMEN

The unexpectedly uncatalyzed reaction between 2-amino-4-arylimidazoles, aromatic aldehydes and Meldrum's acid has selectively led to the corresponding Knoevenagel-Michael adducts containing a free amino group in the imidazole fragment. The adducts derived from Meldrum's acid have been smoothly converted into 1,7-diaryl-3-amino-6,7-dihydro-5H-pyrrolo[1,2-c]imidazol-5-ones and 3-(2-amino-4-aryl-1H-imidazol-5-yl)-3-arylpropanoic acids. The interaction of 2-amino-4-arylimidazoles with aromatic aldehydes or isatins and acyclic methylene active compounds has led to the formation of pyrrolo[1,2-c]imidazole-6-carbonitriles, pyrrolo[1,2-с]imidazole-6-carboxylates and spiro[indoline-3,7'-pyrrolo[1,2-c]imidazoles], which can be considered as the analogues of both 3,3'-spirooxindole and 2-aminoimidazole marine sponge alkaloids.

9.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 5): o703-4, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23723858

RESUMEN

The title compound, C16H12NOSSe(+)·HSO4 (-), was obtained from a mixture of 3-(4-meth-oxy-phen-yl)[1,3]selenazolo[2,3-b][1,3]benzo-thia-zol-4-ium chloride and potassium hydrogen sulfate. In the cation, the benzene ring is twisted by 71.62 (7)° from the tricycle mean plane. In the crystal, O-H⋯O hydrogen bonds link the anions into chains along [100]. The anions in adjacent chains are linked via weak C-H⋯O hydrogen bonds. The crystal packing exhibits short inter-molecular contacts between the chalcogen unit and the O atoms: Se⋯O(anion) 2.713 (3), Se⋯O(cation) 2.987 (3) and S⋯O(anion) 2.958 (3) Å.

10.
Artículo en Inglés | MEDLINE | ID: mdl-24046550

RESUMEN

The title compound, [SnCl2(C5H4NSe)2], is the product of a reaction of 2,2'-dipyridyl diselenide with tin tetra-chloride. The mol-ecule is located about a twofold rotation axis. The coordination environment of the Sn(IV) atom is a distorted octa-hedron, with two bidentate 2-pyridine-seleno-late ligands inclined to each other at an angle of 83.96 (7)°. The two Sn-Cl and two Sn-N bonds are in cis configurations, while the two Sn-Se bonds of 2.5917 (3) Šare in a trans configuration, with an Se-Sn-Se angle of 157.988 (15)°. In the crystal, π-π inter-actions between the pyridine rings [centroid-to-centroid distance of 3.758 (3) Å] and weak inter-molecular C-H⋯Cl hydrogen bonds link the mol-ecules into chains along the c axis.

11.
Mol Divers ; 16(4): 749-57, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23108947

RESUMEN

A facile method for the synthesis of substituted pyrrolo[2,3-c]pyridine-7-ones is developed that applies an acid-promoted intramolecular cyclization of 2-pyrrolecarboxylic acid amidoacetals as key step. The synthesis is easily scaled up to 1.5 mol quantity with no yield decrease. The alkylation/arylation reaction of the pyrrolo[2,3-c]pyridine-7-ones proceeds regioselectively giving N6-substituted derivatives.


Asunto(s)
Piridinas/síntesis química , Piridonas/síntesis química , Pirroles/síntesis química , Alquilación , Ciclización , Espectroscopía de Resonancia Magnética , Estructura Molecular , Peso Molecular , Prolina/análogos & derivados , Prolina/química , Piridonas/química , Pirroles/química
12.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): m875-6, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22807723

RESUMEN

The title compound, [SnCl2(C5H4NS)2], is the product of reaction of 2,2'-dipyridyl disulfide with tin tetra-chloride. The Sn(IV) atom adopts a distorted octa-hedral geometry, with the two bidentate pyridine-2-thiol-ate ligands forming two planar four-membered chelate rings. The two Sn-Cl, two Sn-N and two Sn-S bonds are in cis, cis and trans configurations, respectively. The crystal grown from acetonitrile represents a new monoclinic polymorph in space group C2/c with the mol-ecule having twofold rotational symmetry, the Sn(IV) atom lying on the twofold axis. The mol-ecular structure of the monoclinic polymorph is very close to that of the triclinic polymorph studied previously in space group P-1, the mol-ecule occupying a general position [Masaki & Matsunami (1976 ▶). Bull. Chem. Soc. Jpn, 49, 3274-3279; Masaki et al. (1978 ▶). Bull. Chem. Soc. Jpn, 51, 3298-3301]. Apparently, the formation of the two polymorphs is determined by the different systems of inter-molecular inter-actions. In the crystal of the monoclinic polymorph, mol-ecules are bound into ribbons along the c axis by C-H⋯Cl hydrogen bonds, whereas in the crystal of the triclinic polymorph, mol-ecules form chains along the a axis by attractive S⋯S inter-actions. The crystal studied was a pseudo-merohedral twin; the refined BASF value is 0.221 (1).

13.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): m983, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22807800

RESUMEN

The title compound, [SnCl(4)(C(10)H(8)N(2)Se)], was obtained by the reaction of 2,2'-dipyridyl diselenide with tin tetra-chloride. The Sn(IV) ion is coordinated by two N atoms [Sn-N = 2.266 (2) and 2.274 (2) Å] from the bis-(2-pyrid-yl)selenide ligand and four chloride anions [Sn-Cl = 2.3717 (6)-2.3939 (6) Å] in a distorted octa-hedral geometry. The central six-membered chelate ring has a boat conformation with the Se and Sn atoms deviating by 0.692 (3) and 0.855 (3) Å, respectively, from the mean plane through the remaining four ring atoms. The pyridine rings are inclined to each other by a dihedral angle of 49.62 (8)°. The crystal packing exhibits short inter-molecular Se⋯Cl contacts [3.5417 (7) and 3.5648 (7) Å], weak C-H⋯Cl hydrogen bonds and π-π stacking inter-actions between the pyridine rings with a centroid-centroid distance of 3.683 (3) Å.

14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): o1381, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-22590272

RESUMEN

The title compound C(8)H(8)N(2)Se, is the product of the reaction of 2-chloro-1-methyl-benzimidazole with sodium hydro-selenide. The mol-ecule is almost planar (r.m.s. deviation = 0.041 Å) owing to the presence of the long chain of conjugated bonds (Se=C-NMe-C=C-C=C-C=C-NH). The C=Se bond length [1.838 (2) Å] corresponds well to those found in the close analogs and indicates its pronounced double-bond character. In the crystal, mol-ecules form helicoidal chains along the b axis by means of N-H⋯Se hydrogen bonds.

15.
Avian Pathol ; 40(5): 507-14, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21854179

RESUMEN

Infectious bronchitis virus (IBV) isolates recovered in Russia, Ukraine, and Kazakhstan between 2007 and 2010 were subjected to molecular characterization and compared with those isolated a decade ago. The IBV genome was detected in 202 out of 605 field samples from chickens with various clinical signs. Partial sequencing of the S1 gene revealed 153 vaccine strains and 49 field isolates of several genetic groups. Massachusetts, 793/B and D274 remained the predominant IBV genotypes along with QX, whereas B1648, Italy-02, Arkansas and variants accounted for about 12% of the total number. Three IBVs contained recombinant S1 gene sequences comprising genome fragments of QX-type field isolates and vaccine strains H120 (UKR/02/2009) or 4/91 (RF/03/2010), and vaccine strains H120 and D274 (RF/01/2010). The results of the present study showed a significant decline in prevalence of variant IBVs and a further spread of QX-type isolates in commercial chicken flocks in Russia as compared with the 1998 to 2002 data.


Asunto(s)
Proteínas de la Cápside/genética , Pollos/virología , Variación Genética , Genética de Población , Virus de la Bronquitis Infecciosa/genética , Filogenia , Recombinación Genética/genética , Animales , Secuencia de Bases , Análisis por Conglomerados , Cartilla de ADN/genética , Genotipo , Virus de la Bronquitis Infecciosa/clasificación , Kazajstán , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Federación de Rusia , Alineación de Secuencia , Análisis de Secuencia de ADN , Especificidad de la Especie , Ucrania
16.
Avian Pathol ; 40(2): 213-9, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21500042

RESUMEN

An earlier study on commercial chickens and turkeys with a history of respiratory disease established Mycoplasma gallisepticum infection rates on 164 poultry farms of the Russian Federation. Forty-seven (29%) of these poultry farms were M. gallisepticum-positive by polymerase chain reaction but isolation of the mycoplasma was successful only on 10 farms. Five field isolates from different farms were selected for pathogenicity studies in specific pathogen-free chicks. Clinical signs, seroconversion, culture rates, air sac and tracheal lesions and mean tracheal mucosal thickness were all assessed in comparison with the reference strain, S6. Of the five isolates, MG140905 and MG070607 appeared to be slightly more pathogenic than the other three, as indicated by clinical signs, culture-positive rates and lesions, but only isolate MG140905 differed statistically (P < 0.05) from them, thus proving to be the most pathogenic. However, none of the Russian field isolates was as pathogenic as the S6 strain by the parameters measured. Stress or other factors such as concurrent bacterial or viral infections may have served as exacerbating factors for the disease seen in the naturally affected flocks. Sequence analysis of the gapA and mgc2 genes showed that MG140905 clustered with M. gallisepticum R(low) and was more distant from the majority of the Russian isolates.


Asunto(s)
Pollos/microbiología , Infecciones por Mycoplasma/veterinaria , Mycoplasma gallisepticum/genética , Mycoplasma gallisepticum/patogenicidad , Enfermedades de las Aves de Corral/microbiología , Pavos/microbiología , Adhesinas Bacterianas/genética , Sacos Aéreos/patología , Animales , Proteínas Bacterianas/genética , Secuencia de Bases , ADN Bacteriano/química , ADN Bacteriano/genética , Datos de Secuencia Molecular , Infecciones por Mycoplasma/microbiología , Distribución Aleatoria , Federación de Rusia , Análisis de Secuencia de ADN , Organismos Libres de Patógenos Específicos , Tráquea/patología , Virulencia
17.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 12): o3286-7, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22199791

RESUMEN

In the title compound, C(18)H(14)NSe(+)·HSO(4) (-), the cyclo-pentene ring in the cation has an envelope conformation while the central six-membered 1,4-selenazine ring adopts a sofa conformation. The dihedral angle between the planes of the terminal benzene rings is 68.08 (11)°. In the crystal, the anions form chains along the c axis through O-H⋯O hydrogen bonds. Weak C-H⋯O and C-H⋯π hydrogen bonds, as well as attractive Se⋯Se [3.5608 (8) Å] inter-actions, further consolidate the crystal structure.

18.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): o3050, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22220061

RESUMEN

The title compound, C(7)H(5)NSSe, is the product of the reaction of 2-chloro-benzothia-zole with sodium hydro-selenide. The mol-ecule is almost planar (r.m.s. deviation = 0.018 Å) owing to the presence of the long chain of conjugated bonds (Se=C-N-C=C-C=C-C=C). The geometrical parameters correspond well to those of the analog N-methyl-benzothia-zole-2(3H)-selone, demonstrating that the S atom does not take a significant role in the electron delocalization within the mol-ecule. In the crystal, mol-ecules form centrosymmetric dimers by means of inter-molecular N-H⋯Se hydrogen bonds. The dimers have a nonplanar ladder-like structure. Furthermore, the dimers are linked into ribbons propagating in [010] by weak attractive Se⋯S [3.7593 (4) Å] inter-actions.

19.
Dalton Trans ; 50(31): 10689-10691, 2021 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-34165455

RESUMEN

2-Pyridylselenyl halides undergo facile coupling with a triple CN bond of unactivated nitriles. Unprecedented heterocyclization allowed the preparation of a novel class of cationic 1,2,4-selenadiazoles in remarkably high yields. Cationic 1,2,4-selenadiazoles form supramolecular dimers in the crystal via SeN chalcogen bonding, which was studied theoretically.

20.
Dalton Trans ; 50(36): 12730, 2021 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-34494059

RESUMEN

Correction for 'Novel cationic 1,2,4-selenadiazoles: synthesis via addition of 2-pyridylselenyl halides to unactivated nitriles, structures and four-center Se⋯N contacts' by Victor N. Khrustalev et al., Dalton Trans., 2021, 50, 10689-10691, DOI: 10.1039/D1DT01322J.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA