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1.
Graham Smith Urs D. Wermuth Jonathan M. White 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(12):o694-o698
The structures of two compounds of l ‐tartaric acid with quinoline, viz. the proton‐transfer compound quinolinium hydrogen (2R,3R)‐tartrate monohydrate, C9H8N+·C4H5O6−·H2O, (I), and the anhydrous non‐proton‐transfer adduct with quinaldic acid, bis(quinolinium‐2‐carboxylate) (2R,3R)‐tartaric acid, 2C10H7NO2·C4H6O6, (II), have been determined at 130 K. Compound (I) has a three‐dimensional honeycomb substructure formed from head‐to‐tail hydrogen‐bonded hydrogen tartrate anions and water molecules. The stacks of π‐bonded quinolinium cations are accommodated within the channels and are hydrogen bonded to it peripherally. Compound (II) has a two‐dimensional network structure based on pseudo‐centrosymmetric head‐to‐tail hydrogen‐bonded cyclic dimers comprising zwitterionic quinaldic acid species which are interlinked by tartaric acid molecules. 相似文献
2.
Carolina Gastone Jordi Puiggalí Merc Font‐Bardia Lourdes Urpí 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o498-o500
Crystals of the title compound, C8H14ClNO3, belong to the space group Cc and are characterized by an asymmetric unit containing two molecules, both with a twisted conformation. The molecular packing is stabilized by N—H⋯O=C hydrogen bonds between the amide groups of molecules with the same conformation. In addition, hydrogen‐bonded cyclic carboxylic acid dimers are established between molecules with a different conformation. The ClCH2—CONH bond has a cis conformation in order to favour an intramolecular Cl⋯HN electrostatic interaction. Weak intra‐ and intermolecular CH2⋯O=C interactions are also present. 相似文献
3.
Bhumasamudram Jagadish Michael D. Carducci Alice Dawson Gary S. Nichol Eugene A. Mash 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(8):o431-o433
The title methanol solvate, C24H22N4O5·CH3OH, forms an extended three‐dimensional hydrogen‐bonded structure, assisted by the presence of several good donor and acceptor sites. It shows none of the crystal packing features typically expected of piperazinediones, such as amide‐to‐amide R22(8) hydrogen bonding. In this structure the methanol solvent appears to play only a space‐filling role; it is not involved in any hydrogen bonding and instead is disordered over several sites. This study reports, to the best of our knowledge, the first crystal structure of an indane‐containing piperazinedione compound which exhibits a three‐dimensional hydrogen‐bonded structure formed by classical (N—H...O and N—H...N) hydrogen‐bonding interactions. 相似文献
4.
Graham Smith Urs D. Wermuth 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(10):1192-1195
The structures of the 1:1 hydrated proton‐transfer compounds of isonipecotamide (piperidine‐4‐carboxamide) with oxalic acid, 4‐carbamoylpiperidinium hydrogen oxalate dihydrate, C6H13N2O+·C2HO4−·2H2O, (I), and with adipic acid, bis(4‐carbamoylpiperidinium) adipate dihydrate, 2C6H13N2O+·C6H8O42−·2H2O, (II), are three‐dimensional hydrogen‐bonded constructs involving several different types of enlarged water‐bridged cyclic associations. In the structure of (I), the oxalate monoanions give head‐to‐tail carboxylic acid O—H...Ocarboxyl hydrogen‐bonding interactions, forming C(5) chain substructures which extend along a. The isonipecotamide cations also give parallel chain substructures through amide N—H...O hydrogen bonds, the chains being linked across b and down c by alternating water bridges involving both carboxyl and amide O‐atom acceptors and amide and piperidinium N—H...Ocarboxyl hydrogen bonds, generating cyclic R43(10) and R32(11) motifs. In the structure of (II), the asymmetric unit comprises a piperidinium cation, half an adipate dianion, which lies across a crystallographic inversion centre, and a solvent water molecule. In the crystal structure, the two inversion‐related cations are interlinked through the two water molecules, which act as acceptors in dual amide N—H...Owater hydrogen bonds, to give a cyclic R42(8) association which is conjoined with an R44(12) motif. Further N—H...Owater, water O—H...Oamide and piperidinium N—H...Ocarboxyl hydrogen bonds give the overall three‐dimensional structure. The structures reported here further demonstrate the utility of the isonipecotamide cation as a synthon for the generation of stable hydrogen‐bonded structures. The presence of solvent water molecules in these structures is largely responsible for the non‐occurrence of the common hydrogen‐bonded amide–amide dimer, promoting instead various expanded cyclic hydrogen‐bonding motifs. 相似文献
5.
Juan C. Castillo Rodrigo Abonía Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(6):o303-o310
5‐Benzylamino‐3‐tert‐butyl‐1‐phenyl‐1H‐pyrazole, C20H23N3, (I), and its 5‐[4‐(trifluoromethyl)benzyl]‐, C21H22F3N3, (III), and 5‐(4‐bromobenzyl)‐, C20H22BrN3, (V), analogues, are isomorphous in the space group C2/c, but not strictly isostructural; molecules of (I) form hydrogen‐bonded chains, while those of (III) and (V) form hydrogen‐bonded sheets, albeit with slightly different architectures. Molecules of 3‐tert‐butyl‐5‐(4‐methylbenzylamino)‐1‐phenyl‐1H‐pyrazole, C21H25N3, (II), are linked into hydrogen‐bonded dimers by a combination of N—H...π(arene) and C—H...π(arene) hydrogen bonds, while those of 3‐tert‐butyl‐5‐(4‐chlorobenzylamino)‐1‐phenyl‐1H‐pyrazole, C20H22ClN3, (IV), form hydrogen‐bonded chains of rings which are themselves linked into sheets by an aromatic π–π stacking interaction. Simple hydrogen‐bonded chains built from a single N—H...O hydrogen bond are formed in 3‐tert‐butyl‐5‐(4‐nitrobenzylamino)‐1‐phenyl‐1H‐pyrazole, C20H22N4O2, (VI), while in 3‐tert‐butyl‐5‐(3,4,5‐trimethoxybenzylamino)‐1‐phenyl‐1H‐pyrazole, C23H29N3O3, (VII), which crystallizes with Z′ = 2 in the space group P, pairs of molecules are linked into two independent centrosymmetric dimers, one generated by a three‐centre N—H...(O)2 hydrogen bond and the other by a two‐centre N—H...O hydrogen bond. 相似文献
6.
Orde Q. Munro Colin Wilson 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(11):o535-o539
The crystal structures of two symmetrical pyridine‐2‐carboxamides, namely N,N′‐(propane‐1,3‐diyl)bis(pyridine‐2‐carboxamide), C15H16N4O2, (I), and N,N′‐(butane‐1,4‐diyl)bis(pyridine‐2‐carboxamide), C16H18N4O2, (II), exhibit extended hydrogen‐bonded sequences involving their amide groups. In (I), conventional bifurcated amide–carbonyl (N—H)...O hydrogen bonding favours the formation of one‐dimensional chains, the axes of which run parallel to [001]. Unconventional bifurcated pyridine–carbonyl C—H...O hydrogen bonding links adjacent one‐dimensional chains to form a `porous' three‐dimensional lattice with interconnected, yet unfilled, voids of 60.6 (2) Å3 which combine into channels that run parallel to, and include, [001]. 4% of the unit‐cell volume of (I) is vacant. Compound (II) adopts a Z‐shaped conformation with inversion symmetry, and exhibits an extended structure comprising one‐dimensional hydrogen‐bonded chains along [100] in which individual molecules are linked by complementary pairs of amide N—H...O hydrogen bonds. These hydrogen‐bonded chains interlock viaπ–π interactions between pyridine rings of neighbouring molecules to form sheets parallel with (010); each sheet is one Z‐shaped molecule thick and separated from the next sheet by the b‐axis dimension [7.2734 (4) Å]. 相似文献
7.
Thomas Gelbrich Neslihan Zencirci Ulrich J. Griesser 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(1):o55-o58
Both title structures exhibit essentially planar barbiturate rings. The crystal structure of enallylpropymal (5‐allyl‐5‐isopropyl‐1‐methylbarbituric acid), C11H16N2O3, is composed of centrosymmetric N—H...O hydrogen‐bonded dimers, while 1,5‐di(but‐2‐enyl)‐5‐ethylbarbituric acid, C14H20N2O3, forms N—H...O hydrogen‐bonded helical chains. Each of the ten known crystal structures of closely related N‐monosubstituted derivatives of barbituric acid displays one of the fundamental N—H...O hydrogen‐bonded motifs of the two title structures, i.e. either a dimer or a chain. 相似文献
8.
Vladimir A. Basiuk Vadim A. Soloshonok Luc Van Meervelt Elena V. Basiuk 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):598-599
The title compound, C12H19N3O2, is an unusual product of silica‐catalyzed intermolecular condensation of α‐aminoisobutyric acid. The molecule has three types of C—N bonds: a double bond, a cis‐amide bond and single bonds, two of which are typical and two having intermediate lengths due to π‐electron delocalization between C=N and C=O groups. The cis‐amide moieties interact to form dimers via hydrogen bonds which stack in parallel layers. 相似文献
9.
M. Ramos Silva A. Matos Beja J. A. Paixo L. Alte da Veiga A. J. F. N. Sobral A. M. d'A. Rocha Gonsalves 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):1263-1264
In the title compound, C16H17NO4, the benzyloxycarbonyl group is anti to the pyrrolic N atom. The molecules are joined into head‐to‐head dimers by hydrogen bonds involving the carboxylic acid groups. There is orientational disorder of these groups over two positions with approximately equal occupancy. A weaker hydrogen bond between the pyrrolic N atom and the carbonyl O atom of the benzyloxycarbonyl group joins the dimers into chains running parallel to the [110] direction. 相似文献
10.
Balasubramanian Sridhar 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(12):1042-1047
Multicomponent crystals or cocrystals play a significant role in crystal engineering, the main objective of which is to understand the role of intermolecular interactions and to utilize such understanding in the design of novel crystal structures. Molecules possessing carboxylic acid and amide functional groups are good candidates for forming cocrystals. β‐Resorcylic acid monohydrate, C7H6O4·H2O, (I), crystallizes in the triclinic space group P with one β‐resorcylic acid molecule and one water molecule in the asymmetric unit. The cocrystal thymine–β‐resorcylic acid–water (1/1/1), C5H6N2O2·C7H6O4·H2O, (II), crystallizes in the orthorhombic space group Pca21, with one molecule each of thymine, β‐resorcylic acid and water in the asymmetric unit. All available donor and acceptor atoms in (I) and (II) are utilized for hydrogen bonding. The acid and amide functional groups are well known for the formation of self‐complementary acid–acid and amide–amide homosynthons. In (I), an acid–acid homosynthon is observed, while in (II), an amide–acid heterosynthon is present. In (I), the β‐resorcylic acid molecule exhibits the expected intramolecular S(6) motif between the hydroxy and carbonyl O atoms, and an intermolecular R22(8) dimer motif between the carboxylic acid groups; only the former motif is observed in (II). The water solvent molecule in (I) propagates the discrete dimers into two‐dimensional hydrogen‐bonded sheets. In (II), thymine and β‐resorcylic acid molecules do not form self‐complementary amide–amide and acid–acid homosynthons; instead, a thymine–β‐resorcylic acid heterosynthon is observed. With the help of the water molecule, this heterosynthon is aggregated into a three‐dimensional hydrogen‐bonded network. The absence of thymine base pairing in (II) might be linked to the availability of additional functional groups and the preference of the donor and acceptor hydrogen‐bond combinations. 相似文献
11.
G. L. Morgans S. M. Scalzullo M. A. Fernandes J. P. Michael W. A. L. van Otterlo 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(5):o309-o311
The title compound, C20H19NO5S2, crystallizes as an almost 2:1 mixture of two molecular orientations (described as Orient‐A and Orient‐B). The consequences of these two orientations is the formation of three types of N—H...O hydrogen‐bonded dimers in which the (Orient‐A + Orient‐A) dimers are likely to be the most stable, while the mixed (Orient‐A + Orient‐B) dimers are more frequent. Extra interactions in the form of C—H...O and C—H...π interactions act to further stabilize these dimers and probably allow the less energetically favourable (Orient‐A + Orient‐B) and (Orient‐B + Orient‐B) hydrogen‐bonded dimers to exist by preventing their conversion to (Orient‐A + Orient‐A)‐only hydrogen‐bonded dimers during the crystal‐growth process. 相似文献
12.
Chang‐Liang Sun Xiao‐Nan Jiang Chang‐Sheng Wang 《Journal of computational chemistry》2009,30(15):2567-2575
An analytic potential energy function is proposed and applied to evaluate the amide–amide and amide–water hydrogen‐bonding interaction energies in peptides. The parameters in the analytic function are derived from fitting to the potential energy curves of 10 hydrogen‐bonded training dimers. The analytic potential energy function is then employed to calculate the N? H…O?C, C? H…O?C, N? H…OH2, and C?O…HOH hydrogen‐bonding interaction energies in amide–amide and amide–water dimers containing N‐methylacetamide, acetamide, glycine dipeptide, alanine dipeptide, N‐methylformamide, N‐methylpropanamide, N‐ethylacetamide and/or water molecules. The potential energy curves of these systems are therefore obtained, including the equilibrium hydrogen bond distances R(O…H) and the hydrogen‐bonding energies. The function is also applied to calculate the binding energies in models of β‐sheets. The calculation results show that the potential energy curves obtained from the analytic function are in good agreement with those obtained from MP2/6‐31+G** calculations by including the BSSE correction, which demonstrate that the analytic function proposed in this work can be used to predict the hydrogen‐bonding interaction energies in peptides quickly and accurately. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009 相似文献
13.
Muhammad Altaf Helen Stoeckli‐Evans 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(9):o441-o445
The title compounds, C10H9N5O·H2O (L1·H2O) and C16H12N6O (L2), were synthesized by solvent‐free aldol condensation at room temperature. L1, prepared by grinding picolinaldehyde with 2,3‐diamino‐3‐isocyanoacrylonitrile in a 1:1 molar ratio, crystallized as a monohydrate. L2 was prepared by grinding picolinaldehyde with 2,3‐diamino‐3‐isocyanoacrylonitrile in a 2:1 molar ratio. By varying the conditions of crystallization it was possible to obtain two polymorphs, viz. L2‐I and L2‐II; both crystallized in the monoclinic space group P21/c. They differ in the orientation of one pyridine ring with respect to the plane of the imidazole ring. In L2‐I, this ring is oriented towards and above the imidazole ring, while in L2‐II it is rotated away from and below the imidazole ring. In all three molecules, there is a short intramolecular N—H...N contact inherent to the planarity of the systems. In L1·H2O, this involves an amino H atom and the C=N N atom, while in L2 it involves an amino H atom and an imidazole N atom. In the crystal structure of L1·H2O, there are N—H...O and O—H...O intermolecular hydrogen bonds which link the molecules to form two‐dimensional networks which stack along [001]. These networks are further linked via intermolecular N—H...N(cyano) hydrogen bonds to form an extended three‐dimensional network. In the crystal structure of L2‐I, symmetry‐related molecules are linked via N—H...N hydrogen bonds, leading to the formation of dimers centred about inversion centres. These dimers are further linked via N—H...O hydrogen bonds involving the amide group, also centred about inversion centres, to form a one‐dimensional arrangement propagating in [100]. In the crystal structure of L2‐II, the presence of intermolecular N—H...O hydrogen bonds involving the amide group results in the formation of dimers centred about inversion centres. These are linked via N—H...N hydrogen bonds involving the second amide H atom and the cyano N atom, to form two‐dimensional networks in the bc plane. In L2‐I and L2‐II, C—H...π and π–π interactions are also present. 相似文献
14.
Rudy L. Luck G. David Mendenhall 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):602-603
The title compound, C14H21NO, has two molecules in the asymmetric unit. Each molecule forms hydrogen‐bonded dimers about inversion centers via O—H?N hydrogen bonds between oxime groups. The N—O distances in the oxime groups are 1.4160 (15) and 1.4131 (14) Å. 相似文献
15.
Zoran tefani Anton Meden Martin Lutz Antoine M. M. Schreurs Biserka Koji‐Prodi 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(10):o754-o756
The title compound, rac‐(R,R)‐N,N′‐bis(1‐hydroxy‐3‐methyl‐2‐butyl)oxalamide, C12H24N2O4, crystallizes as a non‐merohedral twin in the triclinic space group . The twin is generated by a twofold rotation about c*. The terminal hydroxy groups of molecules related by an inversion center form hydrogen‐bonded dimers. This hydrogen‐bonding pattern is further extended into a one‐dimensional chain by N—H⋯O hydrogen bonds. 相似文献
16.
Doyle Britton 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o510-o514
Two polymorphs of 3,5‐dichloro‐4‐cyanobenzoic acid, C8H3Cl2NO2, viz. triclinic and monoclinic, and its 0.25‐hydrate, C8H3Cl2NO2·0.25H2O, form crystals in which hydrogen bonding and Cl⋯N interactions appear to be equally important to the structures. In all three structures, there are hydrogen‐bonded (COOH) dimers of the well known cyclic type, but in the hydrate there are also dimers in which the two opposing COOH groups are separated by a water molecule. In the monoclinic polymorph and in the hydrate, the intermolecular interactions form two‐dimensional nets interwoven three at a time. For both the triclinic and monoclinic polymorphs, Z′= 2. 相似文献
17.
V. S. Senthil Kumar Ashwini Nangia 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):360-361
The crystal structure of the title compound, C32H28O2, (I), confirms the erythro stereochemistry of the aldol adduct. In the crystal, (I) forms centrosymmetric O—H?O=C hydrogen‐bonded dimers which in turn are connected by C—H?O and C—H?π interactions. 相似文献
18.
Franois Loiseau Reinhard Neier Gaël Labat Helen Stoeckli‐Evans 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):o636-o638
In the title compound, C9H12Br2O3, a (tetrahydrofuran‐2‐ylidene)acetate, the double bond has the Z form. In the tetrahydrofuran group, the relative configuration of the Br atom in the 3‐position and the methyl group in the 5‐position is anti. The compound crystallizes with two independent molecules per asymmetric unit and, in the crystal structure, the individual molecules are linked to their symmetry‐equivalent molecules by C—H⋯O hydrogen bonds, so forming centrosymmetric hydrogen‐bonded dimers. 相似文献
19.
Anthony Linden Boyan Iliev Heinz Heimgartner 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):o339-o343
The title macrocycle, C26H30N2O6, (VI), was obtained by `direct amide cyclization' from the linear precursor 3‐hydroxy‐N‐[1‐methyl‐1‐(N‐methyl‐N‐phenylcarbamoyl)ethyl]‐2‐phenylpropanamide, the N‐methylanilide of rac‐2‐methyl‐2‐[(3‐hydroxy‐2‐phenylpropanoyl)amino]propanoic acid, C13H17NO4, (IV). The reaction proceeds via the intermediate rac‐2‐(2‐hydroxy‐1‐phenylethyl)‐4,4‐dimethyl‐1,3‐oxazol‐5(4H)‐one, C13H15NO3, (V), which was synthesized independently and whose structure was also established. Unlike all previously described analogues, the title macrocycle has the cis‐diphenyl configuration. The 14‐membered ring has a distorted rectangular diamond‐based [3434] configuration and intermolecular N—H⋯O hydrogen bonds link the molecules into a three‐dimensional framework. The propanoic acid precursor forms a complex series of intermolecular hydrogen bonds, each of which involves pairwise association of molecules and which together result in the formation of extended two‐dimensional sheets. The oxazole intermediate forms centrosymmetric hydrogen‐bonded dimers in the solid state. 相似文献
20.
Berislav Peri Janja Makarevi Milan Joki Biserka Koji‐Prodi Mladen
ini 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):865-867
In the title compound, C20H22N4O4·C2H6OS, two distinct hydrogen‐bond systems connect oxalamide groups in one pattern and primary amide groups in the other to form a two‐dimensional network perpendicular to the c axis. These hydrophilic layers are joined to the three‐dimensional structure through C—H?π interactions. The hydrogen‐bonded waved layers shape holes which are occupied by disordered dimethyl sulfoxide solvent molecules. 相似文献