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Two new 1-(thiazol-2-yl)-4,5-dihydropyrazoles have been synthesized from simple precursors, and characterized both spectroscopically and structurally. In addition, two intermediates in the reaction pathway have been isolated and characterized, one of them structurally. The molecules of the intermediate (E)- 1-(4-methoxyphenyl)-3-[4-(prop-2-ynyloxy)phenyl]prop-2-en-1-one, C19H16O3 (I), are linked by a combination of C—HO and C—H(arene) hydrogen bonds to form ribbons. The products (RS)-5-(4-methoxyphenyl)-1-(4- phenythiazol-2-yl)-3-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydro-1H-pyrazole, C28H23N3O2S (II), and (RS)-5-(4-methoxyphenyl)-1-[4-(4-methylphenyl)thiazol-2- yl]-3-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydro-1H-pyrazole, C29H25N3O2S (III), are closely related – differing only by presence or absence of a methyl group at the arylthiazolyl substituent – and crystallize in an isomorphous setting. Both molecules contain an effectively planar dihydro-pyrazole ring, and possess an overall T-shaped structure, which is a characteristic of triaryl-substituted 4,5-dihydro-1-(thiazol-2-yl)pyrazole compounds. The crystal packing is characterized by intermolecular C—HS and C—H (aryl/alkyne) interactions. A combination of two C—H(arene) hydrogen bonds links the product molecules into sheets. [ABSTRACT FROM AUTHOR]

The crystal structures of three benzimidazole esters containing aryl or heterocyclic substituents at position 2 are reported, and all three exhibit disorder of mol­ecular entities. In ethyl 1-methyl-2-[4-(prop-2-yn­oxy)phen­yl]-1H-benzimidazole-5-carboxyl­ate, C20H18N2O3, (I), the prop-2-yn-1-oxyphenyl unit is disordered over two sets of atomic sites having effectively equal occupancies, 0.506 (5) and 0.494 (5). The propyl substituent in ethyl 1-propyl-2-(pyren-1-yl)-1H-benzimidazole-5-carboxyl­ate, C29H24N2O2, (II), is disordered over two sets of atomic sites having occupancies 0.601 (8) and 0.399 (8), and the ester unit in ethyl 1-methyl-2-(5-chloro-3-methyl-1-phenyl-1H-pyrazol-4-yl)-1H-benzimidazole-5-carboxyl­ate, C21H19ClN4O2 (III), is disordered over two sets of atomic sites having occupancies 0.645 (7) and 0.355 (7). In each of the C—H...π(arene) hydrogen bonds in (I), the donor and acceptor form parts of different disorder components, so that no continuous aggregation is possible. The mol­ecules of (II) are linked by a single C—H...O hydrogen bond into C(10) chains, which are linked into sheets by a π–π stacking inter­action, whereas those of (III) are just linked into C(13) chains, again by a single C—H...O hydrogen bond. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

Crystal structures are reported for three amides containing N-benzo[d]thia­zole substituents. In N-(benzo[d]thia­zol-6-yl)-3-bromo­benzamide, C14H9BrN2OS, where the two ring systems are nearly parallel to one another [dihedral angle = 5.8 (2)°], the mol­ecules are linked by N—H...O and C—H...N hydrogen bonds to form ribbons of R3³(19) rings, which are linked into sheets by short Br...Br inter­actions [3.5812 (6) Å]. N-(6-Meth­oxy­benzo[d]thia­zol-2-yl)-2-nitro­benzamide, C15H11N3O4S, crystallizes with Z′ = 2 in space group Pna21: the dihedral angles between the ring systems [46.43 (15) and 66.35 (13)°] are significantly different in the independent mol­ecules and a combination of two N—H...N and five C—H...O hydrogen bonds links the mol­ecules into a three-dimensional network. The mol­ecules of 5-cyclo­propyl-N-(6-meth­oxy­ben­zo[d]thia­zol-2-yl)­isoxazole-3-carboxamide, C15H13N3O3S, exhibit two forms of disorder, in the meth­oxy group and in the cyclo­propyl­isoxazole unit; symmetry-related pairs of mol­ecules are linked into dimers by pairwise N—H...N hydrogen bonds. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

Cyclo-addition reactions between 3-(5-ar-yloxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)-1-(thio-phen-2-yl)prop-2-en-1-ones and thio-semicarbazide leads to the formation of reduced 3,4'-bi-pyrazole-2-carbo-thio-amides. Further cyclo-addition of these inter-mediates with either diethyl acetyl-enedi-carboxyl-ate or 4-bromo-phenacyl bromide leads to reduced 3,4'-bi-pyrazoles carrying oxo-thia-zole or thia-zole substituents, respectively. The structures of two representative inter-mediates and two representative products established unambiguously the regiochemistry of the cyclo-addition reactions. The mol-ecules of 3'-methyl-5'-(2-methyl-phen-oxy)-1'-phenyl-5-(thio-phen-2-yl)-3,4-di-hydro-1'H,2H-3,4'-bi-pyra-zole-2-carbo-thio-amide, C25H23N5OS2 (Ia), are linked by N--H⋯N hydrogen bonds to form simple C(8) chains. The analogous compound 5'-(2,4-di-chloro-phen-oxy)-3'-methyl-1'-phenyl-5-(thio-phen-2-yl)-3,4-di-hydro-1'H,2H-3,4'-bi-pyra-zole-2-carbo-thio-amide hemihydrate crystallizes as a hemihydrate, C24H19Cl2N5OS2⋅0.5H2O (Ib), and the independent components are linked into a chain of spiro-fused R44(20) rings by a combination of O--H⋯N and N--H⋯O hydrogen bonds. In the structure of ethyl (Z)-2-{2-[3'-methyl-1'-phenyl-5-(thio-phen-2-yl)-5'-(2-methyl-phen-oxy)-3,4-di-hydro-1'H,2H-3,4'-bi-pyrazole-2-yl]-4-oxo-4,5-di-hydro-thia-zol-5-yl-idene}acetate, C31H27N5O4S2 (II), inversion-related pairs of mol-ecules are linked by paired C--H⋯π(arene) hydrogen bonds to form cyclic centrosymmetric dimers, but there are no direction-specific inter-molecular inter-actions in 4-(4-bromo-phen-yl)-2-[5'-(2,4-di-chloro-phen-oxy)-3'-methyl-1'-phenyl-5-(thio-phen-2-yl)-3,4-di-hydro-1'H,2H-3,4'-bi-pyrazole-2-yl]-4-thia-zole, C32H22BrCl2N5OS2 (III). Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

Two new N-{[4-(3-aryl-4-sydnonyl­idene­amino)-5-sulfanyl­idene-1H-1,2,4-triazol-3-yl]meth­yl}benzamides have been prepared by acid-promoted condensation reactions between 3-aryl-4-formyl­sydnones and N-[(4-amino-5-sulfanyl­idene-1H-1,2,4-triazol-3-yl)meth­yl]benzamide, and both have been crystallized as ethanol monosolvates. N-{[4-(3-Phenyl-4-sydnonyl­idene­amino)-5-sulfanyl­idene-1H-1,2,4-triazol-3-yl]meth­yl}benzamide ethanol monosolvate, C19H15N7O3S·C2H6O (I), and N-({4-[3-(4-methyl­phen­yl)-4-sydnonyl­idene­amino]-5-sulfanyl­idene-1H-1,2,4-triazol-3-yl}meth­yl)benzamide ethanol monosolvate, C20H17N7O3S·C2H6O (II), differ only in the presence of a methyl group for (II) instead of a hydrogen atom for (I), and in both of them the ethanol component is disordered over two sets of atomic sites having occupancies of 0.836 (6) and 0.164 (6) in (I), and 0.906 (6) and 0.094 (6) in (II). Combinations of O—H···O and N—H···O hydrogen bonds link the mol­ecules into cyclic, centrosymmetric four-mol­ecule aggregates. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

Chalcones of type 4-XC6H4C(O)CH=CHC6H4(OCH2CCH)-4, where X = Cl, Br or MeO, have been converted to the corresponding 4,5-dihydropyrazole-1-carbothioamides using a cyclocondensation reaction with thiosemicarbazide. The chalcones 1-(4-chlorophenyl)-3-[4-(prop-2-ynyloxy)phenyl]prop-2-en-1-one, C18H13ClO2, (I), and 1-(4-bromophenyl)-3-[4-(prop-2-ynyloxy)phenyl]prop-2-en-1-one, C18H13BrO2, (II), are isomorphous, and their molecules are linked into sheets by two independent C-H···π(arene) interactions, both involving the same aryl ring with one C-H donor approaching each face. In each of the products (RS)-3-(4-chlorophenyl)-5-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydropyrazole-1-carbothioamide, C19H16ClN3OS, (IV), (RS)-3-(4-bromophenyl)-5-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydropyrazole-1-carbothioamide, C19H16BrN3OS, (V), and (RS)-3-(4-methoxyphenyl)-5-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydropyrazole-1-carbothioamide, C20H19N3O2S, (VI), the reduced pyrazole ring adopts an envelope conformation with the C atom bearing the 4-prop-2-ynyloxy)phenyl substituent, which occupies the axial site, displaced from the plane of the four ring atoms. Compounds (IV) and (V) are isomorphous and their molecules are linked into chains of edge-fused rings by a combination of N-H···S and C-H···S hydrogen bonds. The molecules of (VI) are linked into sheets by a combination of N-H···S, N-H···N and C-H···π(arene) hydrogen bonds. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

Two new chalcones containing both pyrazole and thiophene substituents have been prepared and structurally characterized. 3-(3-Methyl-5-phenoxy-1-phenyl- 1H-pyrazol-4-yl)-1-(thiophen-2-yl)prop-2-en-1-one, C23H18N2O2S (I), and 3-[3- methyl-5-(2-methylphenoxy)-1-phenyl-1H-pyrazol-4-yl]-1-(thiophen-2-yl)prop- 2-en-1-one, C24H20N2O2S (II), are isomorphous as well as isostructural, and in each the thiophene substituent is disordered over two sets of atomic sites having occupancies 0.844 (3) and 0.156 (3) in (I), and 0.883 (2) and 0.117 (2) in (II). In each structure, the molecules are linked into sheets by a combination of C-- H ⋯N and C--H ⋯O hydrogen bonds. Comparisons are made with some related compounds. [ABSTRACT FROM AUTHOR]

Three title compounds, namely, 2-(4-chlorobenzyl)-5-[(1H-indol-3-yl)methyl]-6- phenylimidazo[2,1-b][1,3,4]thiadiazole, C26H19ClN4S, (I), 2-(4-chlorobenzyl)-6- (4-fluorophenyl)-5-[(1H-indol-3-yl)methyl]imidazo[2,1-b][1,3,4]thiadiazole, C26H18ClFN4S, (II), and 6-(4-bromophenyl)-2-(4-chlorobenzyl)-5-[(1H-indol-3- yl)methyl]imidazo[2,1-b][1,3,4]thiadiazole, C26H18BrClN4S, (III), have been prepared using a reductive condensation of indole with the corresponding 6-aryl-2-(4-chlorobenzyl)imidazo[2,1-b][1,3,4]thiadiazole-5-carbaldehydes (aryl = phenyl, 4-fluorophenyl or 4-bromophenyl), and their crystal structures have been determined. The asymmetric unit of compound (I) consists of two independent molecules and one of the molecules exhibits disorder of the 4-chlorobenzyl substituent with occupancies 0.6289 (17) and 0.3711 (17). Each type of molecule forms a C(8) chain motif built from N--H ⋯ N hydrogen bonds, which for the fully ordered molecule is reinforced by C--H ⋯ π interactions. In compound (II), the chlorobenzyl unit is again disordered, with occupancies 0.822 (6) and 0.178 (6), and the molecules form C(8) chains similar to those in (I), reinforced by C--H ⋯ π interactions involving only the major disorder component. The chlorobenzyl unit in compound (III) is also disordered with occupancies of 0.839 (5) and 0.161 (5). The molecules are linked by a combination of one N--H ⋯ N hydrogen bond and four C--H⋯π interactions, forming a three-dimensional framework. [ABSTRACT FROM AUTHOR]

The reaction of 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde with phenols under basic conditions yields the corresponding 5‐aryloxy derivatives; the subsequent reaction of these carbaldehydes with substituted acetophenones yields the corresponding chalcones, which in turn undergo cyclocondensation reactions with hydrazine in the presence of acetic acid to form N‐acetylated reduced bipyrazoles. Structures are reported for three 5‐aryloxycarbaldehydes and the 5‐piperidino analogue, and for two reduced bipyrazole products. 5‐(2‐Chlorophenoxy)‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde, C17H13ClN2O2, (II), which crystallizes with Z′ = 2 in the space group P, exhibits orientational disorder of the carbaldehyde group in each of the two independent molecules. Each of 3‐methyl‐5‐(4‐nitrophenoxy)‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde, C17H13N3O4, (IV), 3‐methyl‐5‐(naphthalen‐2‐yloxy)‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde, C21H16N2O2, (V), and 3‐methyl‐1‐phenyl‐5‐(piperidin‐1‐yl)‐1H‐pyrazole‐4‐carbaldehyde, C16H19N3O, (VI), (3RS)‐2‐acetyl‐5‐(4‐azidophenyl)‐5′‐(2‐chlorophenoxy)‐3′‐methyl‐1′‐phenyl‐3,4‐dihydro‐1′H,2H‐[3,4′‐bipyrazole] C27H22ClN7O2, (IX) and (3RS)‐2‐acetyl‐5‐(4‐azidophenyl)‐3′‐methyl‐5′‐(naphthalen‐2‐yloxy)‐1′‐phenyl‐3,4‐dihydro‐1′H,2H‐[3,4′‐bipyrazole] C31H25N7O2, (X), has Z′ = 1, and each is fully ordered. The new compounds have all been fully characterized by analysis, namely IR spectroscopy, 1H and 13C NMR spectroscopy, and mass spectrometry. In each of (II), (V) and (IX), the molecules are linked into ribbons, generated respectively by combinations of C—H...N, C—H...π and C—Cl...π interactions in (II), C—H...O and C—H...π hydrogen bonds in (V), and C—H...N and C—H...O hydrogen bonds in (IX). The molecules of compounds (IV) and (IX) are both linked into sheets, by multiple C—H...O and C—H...π hydrogen bonds in (IV), and by two C—H...π hydrogen bonds in (IX). A single C—H...N hydrogen bond links the molecules of (X) into centrosymmetric dimers. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

In the title compound, C61H15ClN2O3, the heterocyclic ring adopts an envelope conformation, folded across the N⋯N line, with the 2,5-di­meth­oxy­phenyl unit occupying a quasi-axial site. There are two N—H⋯O hydrogen bonds in the structure: one hydrogen bond links mol­ecules related by a 41 screw axis to form a C(6) chain, and the other links inversion-related pairs of mol­ecules to form an R2²(8) ring. The ring motif links all of the chains into a continuous three-dimensional framework structure. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

In each of 1-(4-fluorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1 H-pyrazolo[4,3- c]pyridine, C21H19F4N3O2S, (I), 1-(4-chlorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1 H-pyrazolo[4,3- c]pyridine, C21H19ClF3N3O2S, (II), and 1-(3-methylphenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1 H-pyrazolo[4,3- c]pyridine, C22H22F3N3O2S, (III), the reduced pyridine ring adopts a half-chair conformation with the methylsulfonyl substituent occupying an equatorial site. Although compounds (I) and (II) are not isostructural, having the space groups Pbca and P212121, respectively, their molecular conformations are very similar, but the conformation of compound (III) differs from those of (I) and (II) in the relative orientation of the N-benzyl and methylsulfonyl substituents. In compounds (II) and (III), but not in (I), the trifluoromethyl groups are disordered over two sets of atomic sites. Molecules of (I) are linked into centrosymmetric dimers by C-H...π(arene) hydrogen bonds, molecules of (II) are linked by two C-H...O hydrogen bonds to form ribbons of R33(18) rings, which are themselves further linked by a C-Cl...π(arene) interaction, and a combination of C-H...O and C-H...π(arene) hydrogen bonds links the molecules of (III) into sheets. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

The structure of the title compound, C15H13NO, has six independent mol­ecules in the asymmetric unit; in each case, the seven-membered ring adopts a boat conformation and the overall molecular shape is that of a butterfly. All mol­ecules display N—H⋯C=C close contacts, instead of N—H⋯O interactions. The intramolecular dihedral angles between the benzene rings are within the range 43.7 (1)–46.4 (1)° for the six mol­ecules. [ABSTRACT FROM AUTHOR]

Valdecoxib, C16H14N2O3S, is a non-steroidal anti-inflammatory drug containing a planar isoxazole heterocycle which is substituted at the C atoms with two aromatic rings and a methyl group. In addition to one mol­ecule of valdecoxib, there is half a mol­ecule of ethyl methyl ketone in the asymmetric unit of the title compound [systematic name: 4-(5-methyl-3-phenyl­isoxazol-4-yl)­benzene­sulfon­amide ethyl methyl ketone hemisolvate], viz. C16H14N2O3S·0.5C4H8O. The crystal packing is stabilized by N—H⋯O hydrogen bonds. Apart from the orientation of the sulfon­amide group, the conformation of the title compound agrees well with that of the recently published orthorhombic polymorph which does not contain any solvent. [ABSTRACT FROM AUTHOR]

The title compound, C22H21ClN4O, is used as an intermediate for the synthesis of biologically active compounds. Geometric parameters are in the usual ranges. The packing is stabilized by O—H⋯N hydrogen bonding. [ABSTRACT FROM AUTHOR]

The title compound, C16H18N2O2, is a key intermediate for the synthesis of biologically active novel heterocycles, e.g. isoxazolines and isoxazoles. Geometric parameters of the mol­ecule are in the usual ranges. The crystal packing is stabilized by an O—H⋯N hydrogen bond. [ABSTRACT FROM AUTHOR]

The title compound (3-carboxy­piperidinium chloride), C6H12NO2+·Cl−, is the hydro­chloride of nipecotic acid and is used as a drug inter­mediate and in the synthesis of γ-amino­butyric acid (GABA) uptake inhibitors. The geometric parameters are in the normal ranges. The crystal packing is stabilized by O—H⋯Cl and N—H⋯Cl hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, C8H7NO2, serves as an intermediate for the synthesis of citalopram. The packing of the planar mol­ecules is stabilized by N—H⋯O and N—H⋯N hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, morpholinoethyl ( E)-6-(1,3-di­hydro-4-hydroxy-6-methoxy-7-methyl-3-oxo-2-benzo­furan-5-yl)-4-methyl­hex-4-enoate, C23H31NO7, belongs to the group of immunosuppresant drugs. Its crystal structure is stabilized by O—H⋯O and C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, C33H25BrN4, belongs to the class of substituted tetrazoles. This type of compound is an important starting material for the synthesis of pharmaceutically active materials. [ABSTRACT FROM AUTHOR]