共查询到20条相似文献,搜索用时 15 毫秒
1.
Andrzej Gzella Urszula Wrzeciono Wolfram Pppel 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):462-466
The three title compounds, namely (Z)‐1‐(4,5‐dinitroimidazol‐1‐yl)‐3‐morpholinopropan‐2‐one 2,4‐dinitrophenylhydrazone, C16H17N9O9, (IV), (Z)‐3‐morpholino‐1‐(4‐morpholino‐5‐nitroimidazol‐1‐yl)propan‐2‐one 2,4‐dinitrophenylhydrazone, C20H25N9O8, (Va), and (E)‐3‐morpholino‐1‐(4‐morpholino‐5‐nitroimidazol‐1‐yl)propan‐2‐one 2,4‐dinitrophenylhydrazone tetrahydrofuran solvate, C20H25N9O8·C4H8O, (Vb), have been prepared and their structures determined. In (IV), the C‐4 nitro group is nearly perpendicular to the imidazole ring and the C‐4—NO2 bond length is comparable to the value for a normal single Csp2—NO2 bond. In (IV), (Va) and (Vb), the C‐5 nitro group deviates insignificantly from the imidazole plane and the C‐5—NO2 bond length is far shorter in all three compounds than C‐4—NO2 in (IV). In consequence, the C‐4 nitro group in (IV) is easily replaced by morpholine, while the C‐5 nitro group in (IV), (Va) and (Vb) shows an extraordinary stability on treatment with the amine. The E configuration in (Vb) is stabilized by a three‐centre hydrogen bond. 相似文献
2.
Teruki Sugiyama Jiben Meng Teruo Matsuura 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):o242-o246
The crystal structures of the four isomeric organic salts 4‐aminopyridinium 2‐chloro‐4‐nitrobenzoate, (I), 4‐aminopyridinium 2‐chloro‐5‐nitrobenzoate, (II), 4‐aminopyridinium 5‐chloro‐2‐nitrobenzoate, (III), and 4‐aminopyridinium 4‐chloro‐2‐nitrobenzoate, (IV), all C5H7N2+·C7H3ClNO4?, are presented. Compound (I) has one intramolecular hydrogen bond, one intermolecular C—H?O hydrogen bond and π–π‐stacking interactions. Compound (II) has N—H?O, C—H?O and C—H?Cl hydrogen bonds, and Cl?O—C electrostatic interactions. Compound (III) has N—H?O and C—H?O hydrogen bonds. Compound (IV) has a π–π‐stacking interaction, but no C—H?O hydrogen bonds. 相似文献
3.
Maciej Kubicki Pawe Wagner 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(8):o454-o457
In the crystal structures of the two imidazole derivatives 5‐chloro‐1,2‐dimethyl‐4‐nitro‐1H‐imidazole, C5H6ClN3O2, (I), and 2‐chloro‐1‐methyl‐4‐nitro‐1H‐imidazole, C4H4ClN3O2, (II), C—Cl...O halogen bonds are the principal specific interactions responsible for the crystal packing. Two different halogen‐bond modes are observed: in (I), there is one very short and directional C—Cl...O contact [Cl...O = 2.899 (1) Å], while in (II), the C—Cl group approaches two different O atoms from two different molecules, and the contacts are longer [3.285 (2) and 3.498 (2) Å] and less directional. In (I), relatively short C—H...O hydrogen bonds provide the secondary interactions for building the crystal structure; in (II), the C—H...O contacts are longer but there is a relatively short π–π contact between molecules related by a centre of symmetry. The molecule of (I) is almost planar, the plane of the nitro group making a dihedral angle of 6.97 (7)° with the mean plane of the imidazole ring. The molecule of (II) has crystallographically imposed mirror symmetry and the nitro group lies in the mirror plane. 相似文献
4.
Lesaw Siero B. Nagaraj B. Prabhuswamy H. S. Yathirajan P. Nagaraja R. S. Narasegowda S. L. Gaonkar 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):o821-o823
The title compound (systematic name: {2‐butyl‐4‐chloro‐1‐[2′‐(2‐trityl‐2H‐tetrazol‐5‐yl)biphenyl‐4‐ylmethyl]‐1H‐imidazol‐5‐yl}methanol), C41H37ClN6O, crystallizes in the centrosymmetric space group P with two independent molecules in the asymmetric unit. These molecules differ significantly only in the relative orientations of the rings in the biphenylyltetrazole moieties. One of the molecules shows disorder for three C atoms in the n‐butyl group. Hydrogen bonds link the molecules in an infinite chain along the a axis. 相似文献
5.
Daniel Fernndez Daniel Vega Javier A. Ellena Gustavo Echeverría 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):m418-m420
In the title compound, potassium 2‐butyl‐4‐chloro‐1‐{[2′‐(5‐tetrazolido)biphenyl‐4‐yl]methyl}‐1H‐imidazol‐5‐ylmethanol, K+·C22H22ClN6O?, the imidazole and tetrazole rings are at angles of 85.0 (2) and 51.8 (1)°, respectively, to the phenyl rings to which they are attached, while the dihedral angle between the latter two rings is 46.7 (1)°. The coordination sphere of the metal cation consists of six tetrazoyl N atoms, the methanol O atom and the π cloud of one of the phenyl rings. These interactions determine the formation of columns of molecular anions that lie parallel to the b axis, while hydrogen bonding contributes to intercolumnar cohesion. Far from the centre of the columns, the hydrocarbon chain is immersed in a hydrophobic environment. 相似文献
6.
Yoriko Sonoda Seiji Tsuzuki Nobuyuki Tamaoki Midori Goto 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):o196-o200
The crystal structures of the four E,Z,E isomers of 1‐(4‐alkoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, namely (E,Z,E)‐1‐(4‐methoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C19H17NO3, (E,Z,E)‐1‐(4‐ethoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C20H19NO3, (E,Z,E)‐1‐(4‐nitrophenyl)‐6‐(4‐n‐propoxyphenyl)hexa‐1,3,5‐triene, C21H21NO3, and (E,Z,E)‐1‐(4‐n‐butoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C22H23NO3, have been determined. Intermolecular N⋯O dipole interactions between the nitro groups are observed for the methoxy derivative, while for the ethoxy derivative, two adjacent molecules are linked at both ends through N⋯O dipole–dipole interactions between the N atom of the nitro group and the O atom of the ethoxy group to form a supramolecular ring‐like structure. In the crystal structures of the n‐propoxy and n‐butoxy derivatives, the shortest intermolecular distances are those between the two O atoms of the alkoxy groups. Thus, the nearest two molecules form an S‐shaped supramolecular dimer in these crystal structures. 相似文献
7.
Anthony Linden Cihat afak Frat Aydn 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(10):o711-o713
The title compound, C20H21ClN2O5, has potential calcium modulatory properties. The 1,4‐dihydropyridine ring has the usual shallow boat conformation. The 2‐chloro‐5‐nitrophenyl ring is oriented such that the chloro substituent is in a synperiplanar orientation with respect to the 1,4‐dihydropyridine ring plane, while the nitro substituent sits over the 1,4‐dihydropyridine ring. The cyclohexenone ring has a conformation that is approximately half‐way between that of an envelope and that of a half‐chair. The molecules are linked into chains by intermolecular N—H⋯O hydrogen bonds. 相似文献
8.
Satyen Saha 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o174-o177
The crystal structures of three 4‐amino derivatives of 7‐nitro‐2,1,3‐benzoxadiazole with increasing substituent ring size, viz. 7‐nitro‐4‐(pyrrolidin‐1‐yl)‐2,1,3‐benzoxadiazole, C10H10N4O3, 7‐nitro‐4‐(piperidin‐1‐yl)‐2,1,3‐benzoxadiazole, C11H12N4O3, and 4‐(azepan‐1‐yl)‐7‐nitro‐2,1,3‐benzoxadiazole, C12H14N4O3, have been determined in order to understand their photophysical behaviour. All three were found to crystallize in centrosymmetric space groups. There is considerable electron delocalization compared with the parent compound, although the five‐membered oxadiazole ring apparently does not participate in this. The length of the C—N bond between the amino N atom and the 7‐nitrobenzoxadiazole system is found to be shorter than in similar compounds, as is the C—Nnitro bond. In each structure, the nitro group lies in the plane of the benzoxadiazole unit. 相似文献
9.
Shyamaprosad Goswami Reshmi Mukherjee Kumaresh Ghosh Ibrahim Abdul Razak S. Shanmuga Sundara Raj Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):716-717
In the title compound, N‐(6‐chloro‐4‐oxo‐3,4‐dihydropteridin‐2‐yl)‐2,2‐dimethylpropanamide, C11H12ClN5O2, the rings in the pterin moiety are planar. The amide carbonyl O atom is in syn‐periplanar conformation while the C—N—C—C propanamide linkage is antiperiplanar. The N—H?N and N—H?O intermolecular hydrogen bonds transform the molecules into infinite chains. 相似文献
10.
Bin Li Yu‐Ming Lan Chi‐Tung Hsu Zhen‐Long Liu Hai‐Bin Song Chao Wu Hua‐Zheng Yang 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):o122-o126
The structures of methyl 5‐[2‐chloro‐4‐(trifluoromethyl)phenoxy]‐2‐nitrobenzoate, C15H9ClF3N3O5, (I), methyl 2‐chloro‐5‐[3‐methyl‐2,6‐dioxo‐4‐(trifluoromethyl)‐1,2,3,6‐tetrahydropyrimidin‐1‐yl]benzoate, C14H10ClF3N2O4, (II), and 2‐[4‐chloro‐2‐fluoro‐5‐(prop‐2‐ynyloxy)phenyl]‐4‐(trifluoromethyl)piperidine‐2,6‐dione, C15H10ClF4NO3, (III), are similar in their dihedral angles and in the distances between the farthest two atoms. There are two independent molecules in the structure of (I). The dihedral angles between the two aromatic rings in each molecule in (I), between the benzene and tetrahydropyrimidine rings in (II), and between the benzene ring and the five‐atom planar portion of the piperidine‐2,6‐dione ring in (III) are 80.78 (11)/89.75 (11), 89.13 (9) and 87.52 (13)°, respectively. The distances between the farthest two atoms, viz. O⋯F in the two molecules of (I), and Cl⋯F in (II) and (III), are 11.763 (7)/11.953 (6), 10.734 (10) and 10.889 (9) Å, respectively. In all three crystal structures, the molecules are linked to generate sheets of molecules via C—H⋯O interactions. 相似文献
11.
Boris B. Averkiev Mikhail Yu. Antipin Aleksey B. Sheremetev Tatiana V. Timofeeva 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o383-o387
In earlier papers, we described the synthesis and structures of bis(3‐nitrofurazan‐4‐yl) ether, C4N6O7, (I), bis[3‐(nitro‐N,N,O‐azoxy)furazan‐4‐yl] ether, C4N10O9, (II), and bis[3‐(5H‐[1,2,3]triazolo[4,5‐c]furazan‐5‐yl)furazan‐4‐yl] ether, C8N14O5, (III). Here we compare the structures of (I)–(III) with those of four 3‐cyanodifurazanyl ethers, namely bis(3‐cyanofurazan‐4‐yl) ether, C6N6O3, (IV), 3‐cyanofurazanyl 3‐nitrofurazanyl ether, C5N6O5, (V), 3,4‐bis(3‐cyanofurazan‐4‐yloxy)furazan, C8N8O5, (VI), and bis[3‐(3‐cyanofurazan‐4‐yloxy)furazan‐4‐yl]diazene, C10N12O6, (VII). It was found that the geometric parameters of the difurazanyl ether fragments are similar in these structures and therefore not influenced by substituent effects; however, the conformation of this fragment is different, viz. structures (I), (III), (V) and (VI) have approximate C2 symmetry, and structures (II), (IV) and (VII) have Cs symmetry. Dense crystal packing (1.626–1.898 Mg m−3) is characteristic for all these hydrogen‐free compounds. A linear correlation is also determined between crystal density and `molecular density' (M/V), where M is the mass of a molecule and V is the molecular volume. 相似文献
12.
Maciej Kubicki 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(4):o255-o257
In two closely related 1‐aryl‐2‐methyl‐4‐nitro‐5‐cyanoimidazoles, namely 2‐methyl‐4‐nitro‐1‐phenyl‐1H‐imidazole‐5‐carbonitrile, C11H8N4O2, and 1‐(4‐chlorophenyl)‐2‐methyl‐4‐nitro‐1H‐imidazole‐5‐carbonitrile, C11H7ClN4O2, different weak intermolecular interactions determine the crystal packing. In the 1‐phenyl derivative, dipole–dipole interactions between antiparallel cyano groups connect molecules into centrosymmetric dimers, while in the 1‐(4‐chlorophenyl) derivative, the dimers are connected by C≡N⋯Cl—C halogen bonds. These interactions, together with weak C—H⋯O(N) hydrogen bonds, connect molecules related by subsequent centres of inversion into infinite tapes. 相似文献
13.
Daniel E. Lynch Ian McClenaghan 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o1-o5
The crystal structures of four trifluoromethylnitrobenzene analogues (CF3)C6H3(NO2)[C4H8N2]R (where C4H8N2 is piperazinyl and R is ethyl carboxylate, CO2C2H5, or phenyl, C6H5), have been determined, and their conformations and packing arrangements are compared. The four compounds are ethyl 4‐[4‐nitro‐2‐(trifluoromethyl)phenyl]piperazine‐1‐carboxylate, (I), and ethyl 4‐[2‐nitro‐4‐(trifluoromethyl)phenyl]piperazine‐1‐carboxylate, (II), both C14H16F3N3O4, and 1‐[4‐nitro‐2‐(trifluoromethyl)phenyl]‐4‐phenylpiperazine, (III), and 1‐[2‐nitro‐4‐(trifluoromethyl)phenyl]‐4‐phenylpiperazine, (IV), both C17H16F3N3O2. All molecules adopt a rod‐like conformation, while the asymmetric units of (II) and (IV) contain two unique molecules that pack as monodirectional pairs. All molecules pack with C—H⋯O/F close contacts to all but one of the O atoms and to five of the 18 F atoms. 相似文献
14.
Miao Du Zhi‐Liang Shang Qiang Xu Ruo‐Hua Zhang Xue‐Bing Leng Xian‐He Bu 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):769-770
The crystal structure of the title compound, [CoCl‐(C16H26N6)]ClO4, consists of discrete [CoCl(C16H26N6)]+ cations and perchlorate anions. The five‐coordinate CoII atom has four nitrogen donors from the new mesocyclic ligand 1,5‐bis(1‐methyl‐1H‐imidazol‐2‐ylmethyl)‐1,5‐diazacyclooctane [Co—N 2.046 (3)–2.214 (4) Å], and a chloride anion at the apical site [Co—Cl 2.3184 (13) Å]. The coordination geometry of the complex is essentially square pyramidal. The mesocyclic ligand takes a boat–chair configuration and the two imidazole pendants are not coplanar. The dihedral angle between the two imidazole planes is 15.97°. An H atom from the 1,5‐diazacyclooctane group effectively blocks the axial coordination site opposite the Cl ligand. 相似文献
15.
Susan A. Bourne Katherine De Villiers Timothy J. Egan 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(2):o53-o57
The structures of three compounds with potential antimalarial activity are reported. In N,N‐diethyl‐N′‐(7‐iodoquinolin‐4‐yl)ethane‐1,2‐diamine, C15H20IN3, (I), the molecules are linked into ribbons by N—H⋯N and C—H⋯N hydrogen bonds. In N‐(7‐bromoquinolin‐4‐yl)‐N′,N′‐diethylethane‐1,2‐diamine dihydrate, C15H20BrN3·2H2O, (II), two aminoquinoline molecules and four water molecules form an R54(13) hydrogen‐bonded ring which links to its neighbours to form a T5(2) one‐dimensional infinite tape with pendant hydrogen bonds to the aminoquinolines. The phosphate salt 7‐chloro‐4‐[2‐(diethylammonio)ethylamino]quinolinium bis(dihydrogenphosphate) phosphoric acid, C15H22ClN32+·2H2PO4−·H3PO4, (III), was prepared in order to establish the protonation sites of these compounds. The phosphate ions form a two‐dimensional hydrogen‐bonded sheet, while the aminoquinoline cations are linked to the phosphates by N—H⋯O hydrogen bonds from each of their three N atoms. While the conformation of the quinoline region hardly varies between (I), (II) and (III), the amino side chain is much more flexible and adopts a significantly different conformation in each case. Aromatic π–π stacking interactions are the only supramolecular interactions seen in all three structures. 相似文献
16.
Jrg Schrder Herbert Wenzel Hans‐Georg Stammler Anja Stammler Beate Neumann Harald Tschesche 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):593-596
The title compounds, (2S)‐N‐[5‐(4‐chlorophenyl)‐2,3‐dihydro‐6H‐1,3,4‐thiadiazin‐2‐ylidene]‐2‐[(phenylsulfonyl)amino]propanamide, C18H17ClN4O3S2, (I), (2R)‐N‐[5‐(4‐fluorophenyl)‐6H‐1,3,4‐thiadiazin‐2‐yl]‐2‐[(phenylsulfonyl)amino]propanamide, C18H17FN4O3S2, (II), and (2S)‐N‐[5‐(5‐chloro‐2‐thienyl)‐6H‐1,3,4‐thiadiazin‐2‐yl]‐2‐[(phenylsulfonyl)amino]propanamide, C16H15ClN4O3S3, (III), are potent inhibitors of matrix metalloproteinases. In all three compounds, the thiadiazine ring adopts a screw‐boat conformation. The molecules of compound (I) show a short intramolecular NAla—H?Nexo hydrogen bond [N?N 2.661 (3) Å] and are linked into a chain along the c axis by Nendo—H?Sendo and Nendo—H?OAla hydrogen bonds [N?S 3.236 (3) and N?O 3.375 (3) Å] between neighbouring molecules. In compound (II), the molecules are connected antiparallel into a chain along the a axis by Nexo—H?OAla and NAla—H?Nendo hydrogen bonds [N?O 2.907 (6) and N?N 2.911 (6) Å]. The molecules of compound (III) are dimerized antiparallel through Nexo—H?Nendo hydrogen bonds [N?N 2.956 (7) and 2.983 (7) Å]. The different hydrogen‐bonding patterns can be explained by an amido–imino tautomerism (prototropic shift) shown by different bond lengths within the 6H‐1,3,4‐thiadiazine moiety. 相似文献
17.
Daniel E. Lynch Ian McClenaghan 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(11):o641-o643
Two chemical isomers of 3‐nitrobenzotrifluoride, namely 1‐(4‐chlorophenylsulfanyl)‐2‐nitro‐4‐(trifluoromethyl)benzene, C13H7ClF3NO2S, (I), and 1‐(4‐chlorophenylsulfanyl)‐4‐nitro‐2‐(trifluoromethyl)benzene, C13H7ClF3NO2S, (II), have been prepared and their crystal structures determined with the specific purpose of forming a cocrystal of the two. The two compounds display a similar conformation, with dihedral angles between the benzene rings of 83.1 (1) and 76.2 (1)°, respectively, but (I) packs in P while (II) packs in P21/c, with C—H⋯O interactions. No cocrystal could be formed, and it is suggested that the C—H⋯O associations in (II) prevent intermolecular mixing and promote phase separation. 相似文献
18.
Hiroyuki Ishida Bilkish Rahman Setsuo Kashino 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):876-879
2‐Chloro‐4‐nitrobenzoic acid and 2‐chloro‐5‐nitrobenzoic acid form O—H?N hydrogen bonds with pyrazine to afford 2:1 complexes of 2C7H4ClNO4·C4H4N2, (I) and (II), respectively, that are located on inversion centers. The 2C7H4ClNO4·C4H4N2 units in both complexes are connected by weak C—H?O hydrogen bonds; the units build a three‐dimensional hydrogen‐bond network in (I) and a ribbon structure in (II). 相似文献
19.
Robert T. Stibrany Harvey J. Schugar Joseph A. Potenza 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):o354-o357
Two of the title compounds, namely (E)‐1,2‐bis(1‐methylbenzimidazol‐2‐yl)ethene, C18H16N4, (Ib), and (E)‐1,2‐bis(1‐ethylbenzimidazol‐2‐yl)ethene, C20H20N4, (Ic), consist of centrosymmetric trans‐bis(1‐alkylbenzimidazol‐2‐yl)ethene molecules, while 3‐ethyl‐2‐[(E)‐2‐(1‐ethylbenzimidazol‐2‐yl)ethenyl]benzimidazol‐1‐ium perchlorate, C20H21N4+·ClO4−, (II), contains the monoprotonated analogue of compound (Ic). In the three structures, the benzimidazole and benzimidazolium moieties are essentially planar; the geometric parameters for the ethene linkages and their bonds to the aromatic groups are consistent with double and single bonds, respectively, implying little, if any, conjugation of the central C=C bonds with the nitrogen‐containing rings. The C—N bond lengths in the N=C—N part of the benzimidazole groups differ and are consistent with localized imine C=N and amine C—N linkages in (Ib) and (Ic); in contrast, the corresponding distances in the benzimidazolium cation are equal in (II), consistent with electron delocalization resulting from protonation of the amine N atom. Crystals of (Ib) and (Ic) contain columns of parallel molecules, which are linked by edge‐over‐edge C—H⋯π overlap. The columns are linked to one another by C—H⋯π interactions and, in the case of (Ib), C—H⋯N hydrogen bonds. Crystals of (II) contain layers of monocations linked by π–π interactions and separated by both perchlorate anions and the protruding ethyl groups; the cations and anions are linked by N—H⋯O hydrogen bonds. 相似文献
20.
Vladimir N. Nesterov Elena A. Viltchinskaia 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):616-618
The structures of the title compounds, C15H13N3O4, (I), and C16H15N3O5 [IUPAC name: ethyl 6‐amino‐5‐cyano‐2‐methyl‐4‐(3‐nitrophenyl)‐4H‐pyrano‐3‐carboxylate], (II), are very similar, with the heterocyclic rings adopting boat conformations. The pseudo‐axial m‐nitrophenyl substituents are rotated by 84.0 (1) and 98.7 (1)° in (I) and (II), respectively, with respect to the four coplanar atoms of the boat. The dihedral angles between the phenyl rings and nitro groups are 12.1 (2) and 8.4 (2)° in (I) and (II), respectively. The two compounds have similar patterns of intermolecular N—H?O and N—H?N hydrogen bonding, which link molecules into infinite tapes along b . 相似文献