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The use of tris(4-aminophenyl)amine (TAPA) as central to the synthesis of both polyimines and polyimides and covalent organic frameworks and inorganic cages, among others, has grown in the last few years. The resulting materials exhibit high performance in their area of application. In this contribution, the crystal structures of two TAPA derivatives, triethyl (nitrilotris(benzene-4,1-diyl))tricarbamate (1) and triethyl 2,2′,2″-((nitrilotris(benzene-4,1-diyl))tris(azanediyl))tris(2-oxoacetate) (2), are described. The molecular and supramolecular structures of both compounds were compared between them and with analogous compounds. The analyses of their vibrational and 13C-CPMAS NMR spectroscopies, as well as their thermal stability, were included and corelated with the crystal structure. Hirshfeld surface analysis on the crystal structures of both TAPA derivatives revealed the stabilization of the crystal network via the amide N—H∙∙∙O interactions of dispersive nature in the carbamate, whereas dispersive carbonyl–carbonyl interactions also played a competitive role in the supramolecular arrangement of the oxamate. Interaction energy DFT calculations performed at the B3LYP/6-31G(d,p) level allowed us to estimate the energy contributions and nature of several interactions in terms of the stability of both crystal lattices. [ABSTRACT FROM AUTHOR]

(Thio)ureas ((T)Us) and benzothiazoles (BTs) each have demonstrated to have a great variety of biological activities. When these groups come together, the 2-(thio)ureabenzothizoles [(T)UBTs] are formed, improving the physicochemical as well as the biological properties, making these compounds very interesting in medicinal chemistry. Frentizole, bentaluron and methabenzthiazuron are examples of UBTs used for treatment of rheumatoid arthritis and as wood preservatives and herbicides in winter corn crops, respectively. With this antecedent, we recently reported a bibliographic review about the synthesis of this class of compounds, from the reaction of substituted 2-aminobenzothiazoles (ABTs) with iso(thio)cyanates, (thio)phosgenes, (thio)carbamoyl chlorides, 1,1'-(thio)carbonyldiimidazoles, and carbon disulfide. Herein, we prepared a bibliographic review about those features of design, chemical synthesis, and biological activities relating to (T)UBTs as potential therapeutic agents. This review is about synthetic methodologies generated from 1968 to the present day, highlighting the focus to transform (T)UBTs to compounds containing a range substituents, as illustrated with 37 schemes and 11 figures and concluded with 148 references. In this topic, the scientists dedicated to medicinal chemistry and pharmaceutical industry will find useful information for the design and synthesis of this interesting group of compounds with the aim of repurposing these compounds. [ABSTRACT FROM AUTHOR]

Benzimidazole is an important heterocyclic fragment, present in many biologically active compounds with a great variety of therapeutic purposes. Most of the benzimidazole activities are explained through the existence of 1,3-tautomeric equilibrium. As the binding affinity of each tautomer to a protein target depends on an established bioactive conformation, the effect of tautomers on the ligand protein binding mechanism is determinant. In this work, we searched and analyzed a series of reported 13C-NMR spectra of benzazoles and benzazolidine-2-thiones with the purpose of estimating their tautomeric equilibrium. Herein, several approaches to determine this problem are presented, which makes it a good initial introduction to the non-expert reader. This chemical shift difference and C4/C7 signals of benzimidazolidine-2-thione and 1-methyl-2-thiomethylbenzimidazole as references were used in this work to quantitatively calculate, in solution, the pyrrole–pyridine tautomeric ratio in equilibrium. The analysis will help researchers to correctly assign the chemical shifts of benzimidazoles and to calculate their intracyclic or exocyclic tautomeric ratio as well as mesomeric proportion in benzimidazoles. [ABSTRACT FROM AUTHOR]

The (thio)urea and benzothiazole (BT) derivatives have been shown to have a broad spectrum of biological activities. These groups, when bonded, result in the 2-(thio)ureabenzothizoles (TBT and UBT), which could favor the physicochemical and biological properties. UBTs and TBTs are compounds of great importance in medicinal chemistry. For instance, Frentizole is a UBT derivative used for the treatment of rheumatoid arthritis and systemic lupus erythematosus. The UBTs Bentaluron and Bethabenthiazuron are commercial fungicides used as wood preservatives and herbicides in winter corn crops. On these bases, we prepared this bibliography review, which covers chemical aspects of UBTs and TBTs as potential therapeutic agents as well as their studies on the mechanisms of a variety of pharmacological activities. This work covers synthetic methodologies from 1935 to nowadays, highlighting the most recent approaches to afford UBTs and TBTs with a variety of substituents as illustrated in 42 schemes and 13 figures and concluded with 187 references. In addition, this interesting review is designed on chemical reactions of 2-aminobenzothiazoles (2ABTs) with (thio)phosgenes, iso(thio)cyanates, 1,1′-(thio)carbonyldiimidazoles [(T)CDI]s, (thio)carbamoyl chlorides, and carbon disulfide. This topic will provide information of utility for medicinal chemists dedicated to the design and synthesis of this class of compounds to be tested with respect to their biological activities and be proposed as new pharmacophores. [ABSTRACT FROM AUTHOR]

Oxalamic acid derivatives are model molecules used in crystal engineering and molecular recognition both in solution and in the solid state. Despite their growing importance, hardly any information on polymorphism, stability and interrelations of their solid forms can be found in the literature. In this work, the molecular and supramolecular structures of three cocrystal solvates of formula H2pOx·2S (S = DMSO, DMF, ⅓(MeOH·2W); W = H2O) and the dimethylammonium salt of N,N′-(1,4-phenylene)dioxalamic acid (H2pOx) are described. The nature and energetics of non-covalent interactions were explored through computational methods including the evaluation of the Hirshfeld surface, two-dimensional fingerprint plots, energy-framework diagrams and crystal lattice energies. The X-ray structural parameters were correlated with experimental solid state IR, 13C-CPMAS, thermal analysis and SEM to elucidate the unknown molecular and supramolecular structures of two hydromorphs and three desolvated polymorphs of H2pOx. The role of the crystallized solvents was demonstrated to fix the conformation of H2pOx through hydrogen bonding and n/π → π* interactions, favoring the sp–ap conformation to fit the shape of the solvent. The interconversion pathways between the ten solid phases of H2pOx were stablished, relying on the crystal size and temperature to yield a specific solvent-free polymorph. [ABSTRACT FROM AUTHOR]

A detailed structural analysis of the benzimidazole nitroarenes 1‐(4‐nitrophenyl)‐1H‐1,3‐benzimidazole, C13H9N3O2, (I), 1‐(4‐nitrophenyl)‐2‐phenyl‐1H‐1,3‐benzimidazole, C19H13N3O2, (II), and 2‐(3‐methylphenyl)‐1‐(4‐nitrophenyl)‐1H‐1,3‐benzimidazole, C20H15N3O2, (III), has been performed. They are nonplanar structures whose crystal arrangement is governed by Csp2—H…A (A = NO2, Npy and π) hydrogen bonding. The inherent complexity of the supramolecular arrangements of compounds (I) (Z′ = 2) and (II) (Z′ = 4) into tapes, helices and sheets is the result of the additional participation of π– and n–π* (n = O and Npy; π* = Csp2 and ) interactions that contribute to the stabilization of the equi‐energetic conformations adopted by each of the independent molecules in the asymmetric unit. In contrast, compound (III) (Z′ = 1) is self‐paired, probably due to the effect of the steric demand of the methyl group on the crystal packing. Theoretical ab initio calculations confirmed that the presence of the arene ring at the benzimidazole 2‐position increases the rotational barrier of the nitrobenzene ring and also supports the electrostatic nature of the orthogonal ONO…Csp2 and Npy…NO2 interactions. [ABSTRACT FROM AUTHOR]

Two new molecular structures, namely 1,3-bis(trimethylsilyl)-1 H-benzimidazole-2(3 H)-thione, C13H22N2SSi2, (2), and 1-trimethylsilyl-1 H-benzimidazole-2(3 H)-thione, C10H14N2SSi, (3), are reported. Both systems were derived from 1 H-benzimidazole-2(3 H)-thione. Noncovalent C-H...π interactions between the centroid of the benzmidazole system and the SiMe3 groups form helicoidal arrangements in (2). Dimerization of (3) results in the formation of R22(8) rings via N-H...S interactions, along with parallel π-π interactions between imidazole and benzene rings. [ABSTRACT FROM AUTHOR]

The title compound, C12H13NO4, is one of the few examples that exhibits a syn conformation between the amide and ester carbonyl groups of the oxalyl group. This conformation allows the engagement of the amide H atom in an intramolecular three-centred hydrogen-bonding S(6) S(5) motif. The compound is self-assembled by C=O...C=O and amide-π interactions into stacked columns along the b-axis direction. The concurrence of both interactions seems to be responsible for stabilizing the observed syn conformation between the carbonyl groups. The second dimension, along the a-axis direction, is developed by soft C-H...O hydrogen bonding. Density functional theory (DFT) calculations at the B3LYP/6-31G(d,p) level of theory were performed to support the experimental findings. [ABSTRACT FROM AUTHOR]

Intramolecular hydrogen bond (HB) formation was analyzed in the model compounds N-(2-benzoylphenyl)acetamide, N-(2-benzoylphenyl)oxalamate and N1,N2-bis(2-benzoylphenyl)oxalamide. The formation of three-center hydrogen bonds in oxalyl derivatives was demonstrated in the solid state by the X-ray diffraction analysis of the geometric parameters associated with the molecular structures. The solvent effect on the chemical shift of H6 [δH6(DMSO-d6)–δH6(CDCl3)] and Δδ(ΝΗ)/ΔT measurements, in DMSO-d6 as solvent, have been used to establish the energetics associated with intramolecular hydrogen bonding. Two center intramolecular HB is not allowed in N-(2-benzoylphenyl)acetamide either in the solid state or in DMSO-d6 solution because of the unfavorable steric effects of the o-benzoyl group. The estimated ΔH° and ΔS° values for the hydrogen bonding disruption by DMSO-d6 of 28.3(0.1) kJ·mol-1 and 69.1(0.4) J·mol-1·K-1 for oxalamide, are in agreement with intramolecular three-center hydrogen bonding in solution. In the solid, the benzoyl group contributes to develop 1-D and 2-D crystal networks, through C–H•••A (A = O, π) and dipolar C=O•••A (A = CO, π) interactions, in oxalyl derivatives. To the best of our knowledge, this is the first example where three-center hydrogen bond is claimed to overcome steric constraints. [ABSTRACT FROM AUTHOR]

The reactions of the benzimidazole nitrogen atoms and the exocyclic amino group of 2-aminobenzimidazole with CS2 in NaOH basic medium followed by methylation with methyl iodide was explored. With careful control of the stoichiometric quantities and addition sequences, this set of reactions allows the selective functionalization of the benzimidazole ring with N-dithiocarbamate, S-methyldithiocarbamate or dimethyldithiocarboimidate groups. The products were characterized by 1H-, 13C-NMR spectroscopy and three of them by X-ray diffraction analysis. The preferred isomers, tautomers and conformers were established. [ABSTRACT FROM AUTHOR]

In the title compound, C24H36N6O6·C2H6OS, the carbonyl groups are in an antiperiplanar conformation, with O=C-C=O torsion angles of 178.59 (15) and −172.08 (16)°. An intramolecular hydrogen-bonding pattern is depicted by four N-H...O interactions, which form two adjacent S(5) S(5) motifs, and an N-H...N interaction, which forms an S(6) ring motif. Intermolecular N-H...O hydrogen bonding and C-H...O soft interactions allow the formation of a meso-helix. The title compound is the first example of a helical 1,2-phenylenedioxalamide. The oxalamide traps one molecule of dimethyl sulfoxide through N-H...O hydrogen bonding. C-H...O soft interactions give rise to the two-dimensional structure. [ABSTRACT FROM AUTHOR]

Symmetric and non-symmetric 2-(N-H, N-methyl, N-ethylenyl and N-aryl)guanidinebenzothiazoles were synthesized from the reaction of ammonia, methylamine, pyrrolidine and aniline with dimethyl benzo[d]thiazol-2-yl-carbonodithioimidate (5) as intermediate. The products were characterized by 1H-, 13C-NMR spectroscopy and three of them by X-ray diffraction analysis. HN-phenyl protons formed intramolecular hydrogen bonds that assist the stereochemistry of the second substituent, whereas the HN-alkyl protons were involved in intermolecular hydrogen bonding. [ABSTRACT FROM AUTHOR]

In this contribution the supramolecular architecture of a series of six 1,3-phenyl-dioxalamic molecular clefts is described. The conformation was controlled by the use of Me and OMe group substitution in the phenyl spacer. The structural and conformational study was carried out by X-ray diffraction analysis, DFT calculations at PBEPBE 6-31+G (3df, 3pd) theory level and variable temperature 1H NMR in solution. The C2-Me group exerts a dual influence on the conformation adopting the endo(sc) or exo(ac) conformations in the oxalamic arms, meanwhile the C2-OMe group leads to the adoption of the exo(ap) conformation. DFT study results showed that the exo(ap)–exo(ap) conformation is more stable than the other conformations due to the conjugation that stabilizes the molecule and minimizes the conformational energy. Supramolecular arrays in oxalamate/oxalamide derivatives of 1,3-diaminobenzene, 2-methyl-benzene-1,3-diamine and 2,4,6-trimethyl-benzene-1,3-diamine are directed by self-complementary N–HO hydrogen bonding interactions, whose organization in the crystal depends on the twist of the oxalamic arms, meanwhile in oxalamate/oxalamide derivatives of 5-tert-butyl-2,6-diamineanisol with an exo(ap)–exo(ap) conformation, the supramolecular arrays are directed by π-stacking, dipolar carbonyl–carbonyl interactions and C–HO soft contacts. N1,N1′-(1,3-(2,4,6-Trimethyl)-phenyl)-bis-(N2-(2-(2-hydroxyethoxy)ethyl)oxalamide) adopts the form of a supramolecular meso-helix, which is the first example of helical 1,3-phenyl-dioxalamide. [ABSTRACT FROM AUTHOR]

The thermal [4+2] cycloadditions of 3-acetyl-, 3-carbamoyl, and 3-ethoxycarbonylcoumarins with 2,3-dimethyl-1,3-butadiene under solvent free conditions are reported, as well as the epoxidation reactions of some adducts. Discussion is focused on the structural features of the Diels-Alder adducts and their epoxides, based upon NMR, X-ray, and mass spectral data, and supported by ab initio theoretical calculations. [ABSTRACT FROM AUTHOR]

Abstract: The reaction of [Ru3(CO)12] with the phosphorus chalcogenide ligands (EPR2)()NH [E=E′=S, R=Ph, R′=Me (L1) and E=E′=Se, R=R′=Ph (L2)] produced the complexes [Ru3(μ2-H)(μ3-S){μ2-S,S,P′-(SPPh2)(PMe2)N}(CO)8] 1, [Ru3(μ2-H)(μ3-S){μ2-S,S,P′-(SPMe2)(PPh2)N}(CO)8] 2, [Ru3(μ3-S)2{μ2-P,P′-(Ph2P)(PMe2)NH}(CO)7] 3, [Ru4(μ4-S)2{μ2-P,P′-(Ph2P)(PMe2)NH}(CO)8(μ2-CO)] 4, [Ru3(μ2-H)(μ3-Se){μ2-Se,Se,P′-(SePPh2)(PPh2)N}(CO)8], 5, [Ru3(μ3-Se)2{μ2-P,P′-(PPh2)2NH}(CO)7] 6, and [Ru4(μ4-Se)2{μ2-P,P′-(PPh2)2NH}(CO)8(μ2-CO)] 7, indicating that cleavage of one of the Pf the ligand is one of the first steps in the reaction, followed by the cleavage the remaining P bond. The isostructural tellurium compound, [Ru4(μ4-Te)2{μ2-P,P′-(PPh2)2NH}(CO)8(μ2-CO)] 8, was also prepared through the reaction of [Ru3(CO)12] with elemental Te and (PPh2)2NH. When the monothio ligand (SPPh2)(OPPh2)NH (L3) was used, a mononuclear derivative, [Ru{(SPPh2)(OPPh2)N}2(CO)2] 9, was formed suggesting that the presence of an oxygen atom favors the breaking of the metal-metal bonds instead of that of the Pll these Ru complexes were characterized by spectroscopic methods and the X-ray crystal structures of complexes 1, 2, 3, 6, 8 and 9 were determined, thus allowing comparison between similar compounds containing different donating chalcogen atoms. [Copyright &y& Elsevier]

The carboxylic acid group and the double bond are coplanar in (E)-3-(benzoxazol-2-yl)prop-2-enoic acid, C10H7NO3, whereas in isomeric (Z)-3-(benzoxazol-2-yl)prop-2-enoic acid, also C10H7NO3, they are almost orthogonal. In both isomers, a strong O-H···N hydrogen bond, with the carboxylic acid group as a donor and the pyridine-like N atom as an acceptor, and weak C-H···O interactions contribute to the observed supramolecular structures, which are completed by π-π stacking interactions between oxazole and benzenoid rings. [ABSTRACT FROM AUTHOR]

In exo-2-(3,5-dioxo-10-oxa-4-azatricyclo[ 5.2.1.02,6]dec-8-en-4-yl)phenyl acetate, C16H13NO5, the plane of the acetoxy group lies almost perpendicular to that of the phenyl ring [dihedral angle = 89.8 (1)°], in contrast with the smaller deviations found in the para isomer exo-4-(3,5-dioxo-lO-oxa-4-azatricyclo[5.2.1.02,6]dec-8-en-4-yl)phenyl acetate, C16H13NO5, these being 63.6 (1) and 37.0 (1)° for the two crystallographically independent molecules. Irrespective of the position of the acetoxy group, both compounds pack through soft CH…X (X is O or phenyl) interactions, forming interlinked centrosymmetric tetramers in the bc plane. [ABSTRACT FROM AUTHOR]

The monosubstituted [H4Ru4(CO)11L] derivatives where L=P(C6F5)3, PMe2Ph, P(OMe)3 and P(OEt)3 (compounds 1 to 4, respectively) were synthesized, the crystal structure of 1, 2 and 4 were determined by X-ray diffraction (that of compound 3 had been determined previously but not fully reported so we obtained it again) and their dynamical behavior studied by 1H, 31P and 19F NMR. The structures of compounds 1, 3 and 4 show the common tetrahedral structure with four long (hydride bridged) and two short metal–metal bonds with the P-donor ligand transoid to an unbridged Ru–Ru bond. The structure of 2 is different since the M–M bonds to the Ru atom bonded to the phosphine, are all hydride-bridged. The variable temperature NMR studies of 1, 2 and 3 show dynamical behaviour similar to what had been reported for compound 4. However we propose that some of the structures involved in the equilibrium have the phosphorus substituent transoid to a bridged Ru–Ru bond. [Copyright &y& Elsevier]

Nowadays, organic chemists are interested in the field of heterocyclic chemistry due to its use in the synthesis of a great variety of biologically active compounds. Heterocyclic compounds are widely found in nature and are essential for life. Among these, some natural nitrogen containing heterocyclic compounds have been used as chemotherapeutic agents. Their attachment to sugar molecules either as thioglycosides or as nucleosides analogues plays an important role in vital biological processes as well as in synthetic organic chemistry. Molecules containing benzothiazole (BT) nuclei are of this interesting class of compounds because some of them have been found to have a wide variety of biological activities. In this sense, we selected this topic to review and to then summarize the procedures related to the condensation reactions of o-aminothiophenoles (ATPs) as well as their disulfides with carboxylic acids, esters, orthoesters, acyl chlorides, amides, and nitriles. The condensation reactions with carbon dioxide (CO2) are included. Conventional methods with the use of acid and metal catalysts as well as recent green techniques, such as microwave irradiation, the use of ionic liquids, and ultrasound (US) chemistry, which have proven to have many advantages, were found in the review. [ABSTRACT FROM AUTHOR]

In the title complex salt, [Ir(C5H4O)(C16H22N6)(CO)](CF3O3S), the IrIII centre adopts a distorted octahedral geometry with a facial coordination of the tris(3,5-dimethyl-1 H-pyrazol-1-yl)methane ligand. The C-C distances of the iridacycle are in agreement with its iridacyclohexa-2,5-dien-4-one nature, which presents a nonsymmetric boat-like conformation with the C-Ir-C vertex more bent than the C-C(=O)-C vertex. The supramolecular architecture is mainly directed by CO...CO and CO...π and C sp3-H...O interactions, the arrangement of which depends on the anion. [ABSTRACT FROM AUTHOR]

A new organic salt of metformin, an antidiabetic drug, and N,N′-(1,4-phenylene)dioxalamic acid, was mechanochemically synthesized, purified by crystallization from solution and characterized by single X-ray crystallography. The structure revealed a salt-type crystal hydrate composed of one dicationic metformin unit, two monoanionic units of the acid and four water molecules, namely H2Mf(HpOXA)2∙4H2O. X-ray powder, IR, 13C-CPMAS, thermal and BET adsorption–desorption analyses were performed to elucidate the structure of the molecular and supramolecular structure of the anhydrous microcrystalline mesoporous solid H2Mf(HpOXA)2. The results suggest that their structures, conformation and hydrogen bonding schemes are very similar. To the best of our knowledge, the selective formation of the monoanion HpOXA−, as well as its structure in the solid, is herein reported for the first time. Regular O(δ−)∙∙∙C(δ), O(δ−)∙∙∙N+ and bifacial O(δ−)∙∙∙C(δ)∙∙∙O(δ−) of n→π * charge-assisted interactions are herein described in H2MfA organic salts which could be responsible of the interactions of metformin in biologic systems. The results support the participation of n→π * charge-assisted interactions independently, and not just as a short contact imposed by the geometric constraint due to the hydrogen bonding patterns. [ABSTRACT FROM AUTHOR]

The title compound, C10H12N2O4, crystallizes in the monoclinic non-centrosymmetric space group Pn with Z = 2. The two methyl carbamate groups, —N(H)—C(=O)—OCH3, are twisted away from the aromatic ring mean plane, but form a semiflexible eight-membered cavity involving the atoms of the MeO—C(=O)—N(H)—CH2—CH2—N(H)—C(=O)—OMe group. The NH groups act as hydrogen-bond donors and the C=O groups as acceptors to form intermolecular N—H⋯O hydrogen bonding with an R21(7) motif, generating extended ribbons along the b direction. [ABSTRACT FROM AUTHOR]

The ethyl oxamate group, N-C(O)-C(O)-OEt, in the title compound, alternatively called diethyl N,N′:N,N′-bis- (ethylene)dioxamate, C12H18N2O6, can be considered as being composed of two singly bonded amide and ester functionalities. The ethyl oxamate group is not planar. The two carbonyl groups are almost perpendicular, with an oxalyl O=C-C=O torsion angle of -111.34 (17)°. The molecule is located on an inversion centre. Infinite supramolecular tapes, propagating along the b axis, are formed through soft C—H…O interactions which form a centrosymmetric R22(12) motif. [ABSTRACT FROM AUTHOR]

The title compound, C16H19NO5, crystallizes as a centrosymmetric dimer through strong O-H···O hydrogen-bonding interactions between the hydroxyphenyl and morpholinocarbonyl groups. The morpholinocarbonyl group is almost perpendicular to the propenoate moiety. Electron delocalization in the N-C(=O) fragment leads to the formation of hydrogen-bonded S(5) ring motifs through C-H···O interactions. [ABSTRACT FROM AUTHOR]

Discusses the crystal structure of 2-Amino-1,3-benzothiazole—ethyl coumarin-3-carboxylate. Formation of yellow monoclinic crystals; Intermolecular three-centered hydrogen bonding interaction; Donor-acceptor nature of the compound.

Discusses the crystal structure of ethyl N-phenyloxamate. Intramolecular hydrogen-bonding interactions; Supramolecular arrangement of the compound; Hydrogen-bonding geometry.

In this investigation, the reaction of 2-dithiomethylcarboimidatebenzothiazole with a series of six chiral amino-acids was studied. The reaction proceeds through the isolable sodium salt of SMe-isothiourea carboxylates as intermediates, whose reaction with methyl iodide in stirring DMF as solvent affords SMe-isothiourea methyl esters. The presence of water in the reaction leads to the corresponding urea carboxylates as isolable intermediates, whose methyl esters were obtained. Finally, the urea N-methyl amide derivatives were isolated when SMe-isothiourea or urea methyl esters were reacted with methylamine in the presence of water. The structures of synthesized compounds were established by 1H and 13C nuclear magnetic resonance and the structures of SMe-isothiourea methyl esters derived from (l)-glycine, (l)-alanine, (l)-phenylglycine, and (l)-leucine, by X-ray diffraction analysis. This methodology allows to functionalize 2-aminobenzothiazole with SMe-isothiourea, urea, and methylamide groups derived from chiral amino acids to get benzothiazole derivatives containing coordination sites and hydrogen bonding groups. Further research on the biological activities of some of these derivatives is ongoing. [ABSTRACT FROM AUTHOR]

In the title compound, C9H8N2O4, the 3-nitro­benz­aldehyde oxime and acetyl group have a dihedral angle of 19.5 (4)°. The acetyl carbonyl and 3-nitro­benz­aldehyde oxime groups both adopt a trans configuration ( E). In the crystal structure, mol­ecules are linked by a series of weak intermolecular C—H⋯O interactions, forming a sheet-like structure parallel to the (303) plane. [ABSTRACT FROM AUTHOR]

Two tetrasubstituted tetranuclear ruthenium clusters containing dimethylphenylphosphine [H4Ru4(CO)8(PMe2Ph)4] and [H2Ru4(CO)9(PMe2Ph)4] were prepared and characterized spectroscopically as well as by X-ray crystallography. Both compounds show a structure based on the usual 60-electron tetrahedral framework with each ruthenium atom being bonded to one phosphine ligand. In the case of the nonacarbonyl derivative, one of the ruthenium atoms has one terminal carbonyl group and is also bonded to two semibridging carbonyl groups; two other metal–metal bonds are bridged by the hydride groups. In the case of the octacarbonyl compound all the ruthenium atoms are bonded to two terminal carbonyls and to two bridging hydrides. NMR spectroscopical information of [H4Ru4(CO)8(PMe2Ph)4] suggests the presence of two isomers in solution which we propose to have D2d and Cs symmetries. The observation of the NMR properties gives some observations about conditions that favour coupling between substituents in different ruthenium atoms. [Copyright &y& Elsevier]

Being the base of several non-communicable diseases, including cancer, inflammation is a complex process generated by tissue damage or change in the body homeostatic state. Currently, the therapeutic treatment for chronic inflammation related diseases is based on the use of selective cyclooxygenase II enzyme, COX-2, inhibitors or Coxibs, which have recently regained attention giving their preventive role in colon cancer. Thus, the discovery of new molecules that selectively inhibit COX-2 and other inflammatory mediators is a current challenge in the medicinal chemistry field. 1-Phenylbenzimidazoles have shown potential COX inhibitory activity, because they can reproduce the interaction profile of known COX inhibitors. Therefore, in the present investigation a series of 1,2-diphenylbenzimidazoles (DPBI) with different aromatic substitutions in the para position were synthesized and their interaction with COX-2 and nitric oxide synthase, iNOS, was determined in silico, in vitro and in vivo. Compound 2-(4-bromophenyl)-1-(4-nitrophenyl)-1 H -benzo[ d ]imidazole showed the best inhibition towards COX-2, while compounds N -(4-(2-(4-bromophenyl)-1 H -benzo[ d ]imidazol-1-yl)phenyl)acetamide and N -(4-(2-(4-chlorophenyl)-1 H -benzo[ d ]imidazol-1-yl)phenyl)acetamide diminished the production of NO in vitro. Additionally, they had a significant anti-inflammatory activity in vivo when given orally. [ABSTRACT FROM AUTHOR]

The title compound, C16H17NO3, crystallizes in the space group P , with one mol­ecule in the asymmetric unit. The amide H atom is engaged in an intramolecular N—H⋯O contact to the O atom of one of the two carbonyl groups. The mol­ecules form centrosymmetric dimers through self-complementary C—H⋯O hydrogen-bonding interactions defining the R22(14)[ R21(6)] motif. The supramolecular structure is achieved by aryl C—H⋯π interactions, as well as face-to-face π–π stacking interactions between lactone and benzenoid rings. [ABSTRACT FROM AUTHOR]

Este trabajo describe una ruta de síntesis de la 3-acetilcumarina-(2,4-dinitrofenil)hidrazona (5), así como su caracterización estructural en solución por resonancia magnética nuclear de ¹H y 13C. [ABSTRACT FROM AUTHOR]

Este trabajo describe una ruta de síntesis (condensación de Knoevenagel) sin disolvente (green chemistry) y la caracterización estructural por resonancia magnética nuclear de ¹H y 13C de dos derivados cumarínicos con posible actividad biológica. Estos compuestos son: N-[2-(2-oxo-2H- 1 -benzopirano-3-carboximidil) propil]morfolina (4), N-[2-(2-oxo-2H-1-benzopirano-3-carboximidil)-etil] piperidina (5). [ABSTRACT FROM AUTHOR]