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1.
Andrzej Olczak Magorzata Szczesio Jolanta Goka Czesawa Orlewska Katarzyna Gobis Henryk Foks Marek L. Gwka 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(1):o37-o42
Four compounds showing moderate antituberculostatic activity have been studied to test the hypothesis that the planarity of the 2‐[amino(pyrazin‐2‐yl)methylidene]dithiocarbazate fragment is crucial for activity. N′‐Anilinopyrazine‐2‐carboximidamide, C11H11N5, D1, and diethyl 2,2′‐[({[amino(pyrazin‐2‐yl)methylidene]hydrazinylidene}methylidene)bis(sulfanediyl)]diacetate, C14H19N5O4S2, B1, maintain planarity due to conjugation and attractive intramolecular hydrogen‐bond contacts, while methyl 3‐[amino(pyrazin‐2‐yl)methylidene]‐2‐methyldithiocarbazate, C8H11N5S2, C1, and benzyl 3‐[amino(pyrazin‐2‐yl)methylidene]‐2‐methyldithiocarbazate, C14H15N5S2, C2, are not planar, due to methylation at one of the N atoms of the central N—N bond. The resulting twists of the two molecular halves (parts) of C1 and C2 are indicated by torsion angles of 116.5 (2) and −135.9 (2)°, respectively, compared with values of about 180° in the crystal structures of nonsubstituted compounds. As the methylated derivatives show similar activity against Mycobacterium tuberculosis to that of the nonsubstituted derivatives, maintaining planarity does not seem to be a prerequisite for activity. 相似文献
2.
Magorzata Szczesio Andrzej Olczak Katarzyna Gobis Ida Mazerant Sylwia Kauyska Henryk Foks Marek L. Gwka 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(1):75-79
The emergence of drug‐resistant strains of Mycobacterium tuberculosis has intensified efforts to identify new lead tuberculostatics. Our earlier studies concluded that the planarity of a molecule correlates well with its tuberculostatic activity. According to our hypothesis, only derivatives whose molecules are capable of adopting a planar conformation may show tuberculostatic activity. The structures of three new potentially tuberculostatic compounds, namely N′‐[bis(methylsulfanyl)methylidene]‐N‐methyl‐4‐nitrobenzohydrazide (denoted G1), C11H13N3O3S2, N′‐[bis(benzylsulfanyl)methylidene]‐N‐methyl‐4‐nitrobenzohydrazide (denoted G2), C23H21N3O3S2, and N′‐[(benzylsulfanyl)(methylsulfanyl)methylidene]‐4‐nitrobenzohydrazide (denoted G3), C16H15N3O3S2, were determined by X‐ray diffraction. The significant distortion from planarity caused by the methyl substituent at the N atom of the hydrazide group or the NO2 substituent in the aromatic ring leads to the loss of tuberculostatic activity for G1, G2 and G4 {systematic name: N′‐[bis(methylsulfanyl)methylidene]‐2‐nitrobenzohydrazide}. A similar effect is observed when there are large substituents at the S atoms (G2 and G3). 相似文献
3.
Magorzata Szczesio Andrzej Olczak Katarzyna Gobis Henryk Foks Marek L. Gwka 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(10):o373-o376
Methyl 2‐(3,4‐dichlorobenzoyl)‐1‐methylhydrazinecarbodithioate, C10H10Cl2N2OS2, (F1), butyl 2‐(3,4‐dichlorobenzoyl)‐1‐methylhydrazinecarbodithioate, C13H16Cl2N2OS2, (F2), and 3,4‐dichloro‐N‐(2‐sulfanylidene‐1,3‐thiazinan‐3‐yl)benzamide, C11H10Cl2N2OS2, (F3), were studied by X‐ray diffraction to test our hypothesis that planarity of aryloylhydrazinedithiocarbazic acid esters is a prerequisite for tuberculostatic activity. All compounds examined in this study are inactive and nonplanar due to twists along two specific bonds in the central frame of the molecules. The significant twist at the N—N bond, with an C—N—N—C(S) torsion angle of about 85°, results from repulsion caused by a methyl substituent at the N′ atom of the hydrazide group. The other twist is that within the benzoyl group at the C(O)—Ph bond, i.e. the N—C(=O)—C(phenyl)—C torsion angle: the values found in the studied structures (25–30°) are in agreement with those observed in other compounds containing a similar fragment. As some nonplanar benzoyl derivatives are active, it seems that planarity of the hydrazinedithioate fragment is more important for tuberculostatic activity than planarity of the aryloyl group. 相似文献
4.
Naiem Ahmad Wani Vivek Kumar Gupta Rajni Kant Subrayashastry Aravinda Rajkishor Rai 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(8):776-779
The crystal structure of N‐[(1‐{2‐oxo‐2‐[2‐(pyrazin‐2‐ylcarbonyl)hydrazin‐1‐yl]ethyl}cyclohexyl)methyl]pyrazine‐2‐carboxamide monohydrate (Pyr‐Gpn‐NN‐NH‐Pyr·H2O), C19H23N7O3·H2O, reveals an unusual trans–gauche (tg−) conformation for the gabapentin (Gpn) residue around the Cγ—Cβ (θ1) and Cβ—Cα (θ2) bonds. The molecular conformation is stabilized by intramolecular N—H...N hydrogen bonds and weak C—H...O interactions. The packing of the molecules in the crystal lattice shows a network of strong N—H...O and O—H...O hydrogen bonds together with weak C—H...O and π–π inteactions. 相似文献
5.
Magorzata Szczesio Andrzej Olczak Katarzyna Gobis Henryk Foks Marek L. Gwka 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(3):o99-o103
Dimethyl (3,4‐dichlorobenzoyl)carbonohydrazonodithioate, C10H10Cl2N2OS2, (D1), dibenzyl (3,4‐dichlorobenzoyl)carbonohydrazonodithioate, C22H18Cl2N2OS2, (D2), dimethyl (3,4‐dichlorobenzoyl)‐1‐methylcarbonohydrazonodithioate, C11H12Cl2N2OS2, (D3), 3,4‐dichloro‐N′‐(1,3‐dithiolan‐2‐ylidene)‐N‐methylbenzohydrazide, C11H10Cl2N2OS2, (D4), were synthesized as potential tuberculostatics. Compound (D1) (with two molecules in the asymmetric unit) was the only one showing tuberculostatic activity of the same range as the common drugs isoniazid and pyrazinamide. The molecular structures of the studied compounds depend on the substitution at the N atom adjacent to the carbonyl group. In the case of the unsubstituted derivatives (D1) and (D2), their central frames are generally planar with a twist of the 3,4‐dichlorophenyl ring by 30–40°. Until now, coplanarity of the aromatic ring with the (methylene)carbonohydrazone fragment has been considered a prerequisite for tuberculostatic activity. The N‐methylated derivatives (D3) and (D4) show an additional twist along the N—C(=O) bond by 20–30° due to the spatial repulsion introduced by the methyl substituent. 相似文献
6.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(2):84-90
Searches for new tuberculostatic agents are important considering the occurrence of drug‐resistant strains of Mycobacterium tuberculosis . The structures of three new potentially tuberculostatic compounds, namely isopropyl methyl (2‐hydroxybenzoyl)carbonohydrazonodithioate, C12H16N2O2S2, (Z )‐benzyl methyl (2‐hydroxybenzoyl)carbonohydrazonodithioate, C16H16N2O2S2, and dibenzyl (2‐hydroxybenzoyl)carbonohydrazonodithioate propan‐2‐ol monosolvate, C22H20N2O2S2·C3H8O, were determined by X‐ray diffraction. The mutual orientation of the three main fragments of the compounds, namely an aromatic ring, a dithioester group and a hydrazide group, can influence the biological activity of the compounds. In all three of the structures studied, the C(=O)NH group is in the anti conformation. In addition, the presence of the hydroxy group in the ortho position of the aromatic ring in all three structures leads to the formation of an intramolecular hydrogen bond stabilizing the planarity of the molecules. 相似文献
7.
Kamlakar Avasthi Lakshmi Shukla Ruchir Kant Krishnan Ravikumar 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(6):555-561
The butylidene‐linker models 1‐[2‐(2,6‐dimethylsulfanyl‐9H‐purin‐9‐yl)‐2‐methylidenepropyl]‐4,6‐bis(methylsulfanyl)‐1H‐pyrazolo[3,4‐d]pyrimidine, C18H20N8S4, (XI), 7,7′‐(2‐methylidenepropane‐1,3‐diyl)bis[3‐methyl‐2‐methylsulfanyl‐3H‐pyrrolo[2,3‐d]pyrimidin‐4(7H)‐one], C20H22N6O2S2, (XIV), and 7‐[2‐(4,6‐dimethylsulfanyl‐1H‐pyrazolo[3,4‐d]pyrimidin‐1‐yl)‐2‐methylidenepropyl]‐3‐methyl‐2‐methylsulfanyl‐3H‐pyrrolo[2,3‐d]pyrimidin‐4(7H)‐one, C19H21N7OS3, (XV), show folded conformations in solution, as shown by 1H NMR analysis. This folding carries over to the crystalline state. Intramolecular π–π interactions are observed in all three compounds, but only (XIV) shows additional intramolecular C—H...π interactions in the solid state. As far as can be established, this is the first report incorporating the pyrrolo[2,3‐d]pyrimidine nucleus for such a study. In addition to the π–π interactions, the crystal structures are also stabilized by other weak intermolecular C—H...S/N/O and/or S...N/S interactions. 相似文献
8.
Ligia R. Gomes John Nicolson Low Ana S. M. C. Rodrigues James L. Wardell Camillo H. da Silva Lima Marcus V. N. de Souza 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(5):549-555
The compounds N′‐benzylidene‐N‐methylpyrazine‐2‐carbohydrazide, C13H12N4O, (IIa), N′‐(2‐methoxybenzylidene)‐N‐methylpyrazine‐2‐carbohydrazide, C14H14N4O2, (IIb), N′‐(4‐cyanobenzylidene)‐N‐methylpyrazine‐2‐carbohydrazide dihydrate, C14H11N5O·2H2O, (IIc), N‐methyl‐N′‐(2‐nitrobenzylidene)pyrazine‐2‐carbohydrazide, C13H11N5O3, (IId), and N‐methyl‐N′‐(4‐nitrobenzylidene)pyrazine‐2‐carbohydrazide, C13H11N5O3, (IIe), have dihedral angles between the pyrazine rings and the benzene rings in the range 55–78°. These methylated pyrazine‐2‐carbohydrazides have supramolecular structures which are formed by weak C—H...O/N hydrogen bonds, with the exception of (IIc) which is hydrated. There are π–π stacking interactions in all five compounds. Three of these structures are compared with their nonmethylated counterparts, which have dihedral angles between the pyrazine rings and the benzene rings in the range 0–6°. 相似文献
9.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(3):400-405
The search for new tuberculostatics is an important issue due to the increasing resistance of Mycobacterium tuberculosis to existing agents and the resulting spread of the pathogen. Heteroaryldithiocarbazic acid derivatives have shown potential tuberculostatic activity and investigations of the structural aspects of these compounds are thus of interest. Three new examples have been synthesized. The structure of methyl 2‐[amino(pyridin‐3‐yl)methylidene]hydrazinecarbodithioate, C8H10N4S2, at 293 K has monoclinic (P21/n) symmetry. It is of interest with respect to antibacterial properties. The structure displays N—H…N and N—H…S hydrogen bonding. The structure of N′‐(pyrrolidine‐1‐carbonothioyl)picolinohydrazonamide, C11H15N5S, at 100 K has monoclinic (P21/n) symmetry and is also of interest with respect to antibacterial properties. The structure displays N—H…S hydrogen bonding. The structure of (Z)‐methyl 2‐[amino(pyridin‐2‐yl)methylidene]‐1‐methylhydrazinecarbodithioate, C9H13N4S2, has triclinic (P) symmetry. The structure displays N—H…S hydrogen bonding. 相似文献
10.
Antony Bulanov Igor N. Shcherbakov Leonid D. Popov E. Y. Shasheva P. A. Belikov Zoya A. Starikova 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(3):o85-o88
The structures of new oxaindane spiropyrans derived from 7‐hydroxy‐3′,3′‐dimethyl‐3′H‐spiro[chromene‐2,1′‐isobenzofuran]‐8‐carbaldehyde (SP1), namely N‐benzyl‐2‐[(7‐hydroxy‐3′,3′‐dimethyl‐3′H‐spiro[chromene‐2,1′‐isobenzofuran]‐8‐yl)methylidene]hydrazinecarbothioamide, C27H25N3O3S, (I), at 120 (2) K, and N′‐[(7‐hydroxy‐3′,3′‐dimethyl‐3′H‐spiro[chromene‐2,1′‐isobenzofuran]‐8‐yl)methylidene]‐4‐methylbenzohydrazide acetone monosolvate, C27H24N2O4·C3H6O, (II), at 100 (2) K, are reported. The photochromically active Cspiro—O bond length in (I) is close to that in the parent compound (SP1), and in (II) it is shorter. In (I), centrosymmetric pairs of molecules are bound by two equivalent N—H...S hydrogen bonds, forming an eight‐membered ring with two donors and two acceptors. 相似文献
11.
Jessica Orrego Hernandez Jaime Portilla Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(5):363-368
Cyclohexylamine reacts with 5‐chloro‐3‐methyl‐1‐(pyridin‐2‐yl)‐1H‐pyrazole‐4‐carbaldehyde to give 5‐cyclohexylamino‐3‐methyl‐1‐(pyridin‐2‐yl)‐1H‐pyrazole‐4‐carbaldehyde, C16H20N4O, (I), formed by nucleophilic substitution, but with 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde the product is (Z)‐4‐[(cyclohexylamino)methylidene]‐3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐one, C17H21N3O, (II), formed by condensation followed by hydrolysis. Compound (II) crystallizes with Z′ = 2, and in one of the two independent molecular types the cyclohexylamine unit is disordered over two sets of atomic sites having occupancies of 0.65 (3) and 0.35 (3). The vinylogous amide portion in each compound shows evidence of electronic polarization, such that in each the O atom carries a partial negative charge and the N atom of the cyclohexylamine portion carries a partial positive charge. The molecules of (I) contain an intramolecular N—H...N hydrogen bond, and they are linked by C—H...O hydrogen bonds to form sheets. Each of the two independent molecules of (II) contains an intramolecular N—H...O hydrogen bond and each molecular type forms a centrosymmetric dimer containing one R22(4) ring and two inversion‐related S(6) rings. 相似文献
12.
Tirtha Bhattacharjee Prasanta Gogoi Vedavati G. Puranik Rupesh L. Gawade Pranjit Barman 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(12):o485-o487
In the title compound, C21H18N2OS2, a strong intramolecular N—H...O hydrogen bond [N...O = 2.642 (3) Å] between the amide N atom and the benzoyl O atom forms an almost planar six‐membered ring in the central part of the molecule. In the crystal, molecules are packed through weak N—H...S interactions. Intra‐ and intermolecular hydrogen bonds and van der Waals interactions are the stabilizing forces for the crystal structure. 相似文献
13.
Loredana Canfora Sebastien Pillet Enrique Espinosa Giuseppe Ruisi 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(10):o503-o507
The molecular structure of 7‐amino‐2‐methylsulfanyl‐1,2,4‐triazolo[1,5‐a]pyrimidine‐6‐carboxylic acid is reported in two crystal environments, viz. as the dimethylformamide (DMF) monosolvate, C7H7N5O2S·C3H7NO, (I), and as the monohydrate, C7H7N5O2S·H2O, (II), both at 293 (2) K. The triazolo[1,5‐a]pyrimidine molecule is of interest with respect to the possible biological activity of its coordination compounds. While the DMF solvate exhibits a layered structural arrangement through N...O hydrogen‐bonding interactions, the monohydrate displays a network of intermolecular O...O and N...O hydrogen bonds assisted by cocrystallized water molecules and weak π–π stacking interactions, leading to a different three‐dimensional supramolecular architecture. Based on results from topological analyses of the electron‐density distribution in X—H...O (X = O, N and C) regions, hydrogen‐bonding energies have been estimated from structural information only, enabling the characterization of hydrogen‐bond graph energies. 相似文献
14.
Edison Castro Henry Insuasty Braulio Insuasty Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(11):1064-1068
The title compound, C18H18N4OS2, was prepared by reaction of S,S‐diethyl 2‐thenoylimidodithiocarbonate with 5‐amino‐3‐(4‐methylphenyl)‐1H‐pyrazole using microwave irradiation under solvent‐free conditions. In the molecule, the thiophene unit is disordered over two sets of atomic sites, with occupancies of 0.814 (4) and 0.186 (4), and the bonded distances provide evidence for polarization in the acylthiourea fragment and for aromatic type delocalization in the pyrazole ring. An intramolecular N—H...O hydrogen bond is present, forming an S(6) motif, and molecules are linked by N—H...O and N—H...N hydrogen bonds to form a ribbon in which centrosymmetric R22(4) rings, built from N—H...O hydrogen bonds and flanked by inversion‐related pairs of S(6) rings, alternate with centrosymmetric R22(6) rings built from N—H...N hydrogen bonds. 相似文献
15.
Jun Luo Xin‐Rong Zhang Li‐Li Cui Wei‐Quan Dai Bao‐Shu Liu 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(12):m614-m616
The two new title complexes, [Mn(C5H3N6)2(H2O)2] and [Zn(C5H3N6)2(H2O)2], are isomorphous. In both compounds, the metal atom is located on an inversion center and is coordinated by four N atoms from two 5‐(pyrazin‐2‐yl)‐1H‐tetrazolate anions in the basal plane and by two O atoms of water ligands in the apical positions to form a distorted octahedral geometry. Intermolecular hydrogen‐bond interactions between the uncoordinated N atoms of the tetrazolate anions and the H atoms of the water molecules lead to the formation of a three‐dimensional network. 相似文献
16.
Madeleine Helliwell Salma Moosun Minu G. Bhowon Sabina Jhaumeer‐Laulloo John A. Joule 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(10):o387-o391
The structures of N,N′‐bis(2‐methylphenyl)‐2,2′‐thiodibenzamide, C28H24N2O2S, (Ia), N,N′‐bis(2‐ethylphenyl)‐2,2′‐thiodibenzamide, C30H28N2O2S, (Ib), and N,N′‐bis(2‐bromophenyl)‐2,2′‐thiodibenzamide, C26H18Br2N2O2S, (Ic), are compared with each other. For the 19 atoms of the consistent thiodibenzamide core, the r.m.s. deviations of the molecules in pairs are 0.29, 0.90 and 0.80 Å for (Ia)/(Ib), (Ia)/(Ic) and (Ib)/(Ic), respectively. The conformations of the central parts of molecules (Ia) and (Ib) are similar due to an intramolecular N—H...O hydrogen‐bonding interaction. The molecules of (Ia) are further linked into infinite chains along the c axis by intermolecular N—H...O interactions, whereas the molecules of (Ib) are linked into chains along b by an intermolecular N—H...π contact. The conformation of (Ic) is quite different from those of (Ia) and (Ib), since there is no intramolecular N—H...O hydrogen bond, but instead there is a possible intramolecular N—H...Br hydrogen bond. The molecules are linked into chains along c by intermolecular N—H...O hydrogen bonds. 相似文献
17.
Ligia R. Gomes John Nicolson Low James L. Wardell Alessandra C. Pinheiro Thais C. N. de Mendona Marcus V. N. de Souza 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(3):293-298
The molecular conformations of three N‐alkyl‐2‐(methylsulfanyl)nicotinamide derivatives, namely N‐cyclohexyl‐2‐(methylsulfanyl)nicotinamide, C13H18N2OS, (I), N‐isopropyl‐2‐(methylsulfanyl)nicotinamide, C10H14N2OS, (II), in which there are two molecules in the asymmetric unit which were chosen to form a hydrogen‐bonded pair, and N‐(2‐hydroxyethyl)‐2‐(methylsulfanyl)nicotinamide dihydrate, C9H12N2O2S·2H2O, (III), are compared with those of four unsubstituted N‐alkylnicotinamide compounds. The substituted compounds show a higher degree of torsion of the pyridine ring with respect to the amide group than do the unsubstituted compounds, with dihedral angles in the range 40–60° for the former and 20–35° for the latter. In (I) and (II), the supramolecular structure is defined by amide‐N to carbonyl‐O chains. In (III), the nicotinamide molecules are linked by hydrogen bonds to two water molecules resulting in two linked chains of rings which form the three‐dimensional network. 相似文献
18.
Lars G. J. Hammarstrm Tao Zhang Jos Giralds Mark L. McLaughlin Damon R. Billodeaux Frank R. Fronczek 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):1484-1486
The carboxy group of 2‐methyl‐N‐[(2‐nitrophenyl)sulfonyl]alanine, C10H12N2O6S, forms centrosymmetric hydrogen‐bonded dimers with an O?O distance of 2.629 (2) Å and an intramolecular N—H?O(nitro) hydrogen bond N?O distance of 2.823 (2) Å. 1‐[(2‐Nitrophenyl)sulfonylamino]cyclohexanecarboxylic acid, C13H16N2O6S, has Z′ = 2 and forms similar interactions. 相似文献
19.
Choudhury M. Zakaria George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):m1-m4
In the adduct ferrocene‐1,1′‐diylbis(diphenylmethanol)–1,2‐bis(4‐pyridyl)ethene (1/1), [Fe(C18H15O)2]·C12H10N2, there is an intramolecular O—H?O hydrogen bond in the ferrocenediol component and a single O—H?N hydrogen bond linking the diol to the diamine, which is disordered over two sets of sites, so forming a finite monomeric adduct. In the adduct ferrocene‐1,1′‐diylbis(diphenylmethanol)–1,6‐diaminohexane (2/1), 2[Fe(C18H15O)2]·C6H16N2, the amine lies across a centre of inversion in space group P. There is an intramolecular O—H?O hydrogen bond in the ferrocenediol, and the molecular components are linked by O—H?N and N—H?O hydrogen bonds, one of each type, into a C(13)[R(12)] chain of rings. 相似文献
20.
Jonathan C. Parrish Rudong Shan Edward E. Knaus Michael N. G. James 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):107-109
This analysis establishes the rotameric orientation of the pyridyl‐ring N atom of the title compound, C17H21N3O4·0.5C6H6, as antiperiplanar (ap) to the 1,4‐dihydropyridine H‐4, the absence of an intramolecular hydrogen bond between the 1,4‐dihydropyridine NH and the pyridyl‐N atom, and the unusual planarity of the 1,4‐dihydropyridine ring. 相似文献