Six closely related 4,6-disubstituted 2-amino-5-formylpyrimidines: different ring conformations, polarized electronic structures, and hydrogen-bonded assembly in zero, one, two and three dimensions

Author(s):  
Lina M. Acosta ◽  
Andrés F. Yepes ◽  
Alirio Palma ◽  
Justo Cobo ◽  
Christopher Glidewell

In each of ethylN-{2-amino-5-formyl-6-[methyl(phenyl)amino]pyrimidin-4-yl}glycinate, C16H19N5O3, (I),N-{2-amino-5-formyl-6-[methyl(phenyl)amino]pyrimidin-4-yl}glycinamide, C14H16N6O2, (II), and ethyl 3-amino-N-{2-amino-5-formyl-6-[methyl(phenyl)amino]pyrimidin-4-yl}propionate, C17H21N5O3, (III), the pyrimidine ring is effectively planar, but in each of methylN-{2-amino-6-[benzyl(methyl)amino]-5-formylpyrimidin-4-yl}glycinate, C16H19N5O3, (IV), ethyl 3-amino-N-{2-amino-6-[benzyl(methyl)amino]-5-formylpyrimidin-4-yl}propionate, C18H23N5O3, (V), and ethyl 3-amino-N-[2-amino-5-formyl-6-(piperidin-4-yl)pyrimidin-4-yl]propionate, C15H23N5O3, (VI), the pyrimidine ring is folded into a boat conformation. The bond lengths in each of (I)–(VI) provide evidence for significant polarization of the electronic structure. The molecules of (I) are linked by paired N—H...N hydrogen bonds to form isolated dimeric aggregates, and those of (III) are linked by a combination of N—H...N and N—H...O hydrogen bonds into a chain of edge-fused rings. In the structure of (IV), molecules are linked into sheets by means of two hydrogen bonds, both of N—H...O type, in the structure of (V) by three hydrogen bonds, two of N—H...N type and one of C—H...O type, and in the structure of (VI) by four hydrogen bonds, all of N—H...O type. Molecules of (II) are linked into a three-dimensional framework structure by a combination of three N—H...O hydrogen bonds and one C—H...O hydrogen bond.

2008 ◽  
Vol 64 (5) ◽  
pp. 596-609 ◽  
Author(s):  
Justo Cobo ◽  
Jorge Trilleras ◽  
Jairo Quiroga ◽  
Antonio Marchal ◽  
Manuel Nogueras ◽  
...  

The structures of 12 new N 6-substituted 2-amino-4-chloro-5-formylpyrimidines, where the N 6 substituent is of the type NHR or NR 1 R 2, have been determined. The intramolecular dimensions provide strong evidence for the development of polarized, charge-separated molecular-electronic structures, with the positive charge delocalized over the two exocyclic amino N atoms and with negative charge on the formyl O atom. This polarization appears to be independent of the significant puckering, in seven of the compounds, of the pyrimidine rings from planarity towards boat, twist-boat or screw-boat conformations. In 11 of the compounds studied here, N—H...N hydrogen bonds link pairs of molecules into centrosymmetric R_2^2(8) dimer units, and their overall crystal structures are determined by the patterns of hydrogen bonds by which these units are further linked. Examples are reported in which no further hydrogen bonding occurs; in which the R_2^2(8) dimers are linked into chains of rings, or into sheets; and in which sheets are formed by the π-stacking of hydrogen-bonded chains of rings. In the sole structure lacking the R_2^2(8) dimer motif, N—H...O and N—H...N hydrogen bonds cooperate to generate a three-dimensional framework structure.


2019 ◽  
Vol 75 (10) ◽  
pp. 1494-1506 ◽  
Author(s):  
Haruvegowda Kiran Kumar ◽  
Hemmige S. Yathirajan ◽  
Sabine Foro ◽  
Christopher Glidewell

Twelve 4-(4-methoxyphenyl)piperazin-1-ium salts containing organic anions have been prepared and structurally characterized. The monohydrated benzoate, 4-fluorobenzoate, 4-chlorobenzoate and 4-bromobenzoate salts, C11H17N2O+·C7H5O2 −·H2O (I), C11H17N2O+·C7H4FO2 −·H2O (II), C11H17N2O+·C7H4ClO2 −·H2O (III), and C11H17N2O+·C7H4BrO2 −·H2O (IV), respectively, are isomorphous and all exhibit disorder in the 4-methoxyphenyl unit: the components are linked by N—H...O and O—H...O hydrogen bond to form chains of rings. The unsolvated 2-hydroxybenzoate, pyridine-3-carboxylate and 2-hydroxy-3,5-dinitrobenzoate salts, C11H17N2O+·C7H5O3 − (V), C11H17N2O+·C6H4NO2 − (VI) and C11H17N2O+·C7H3N2O7 − (VII), respectively, are all fully ordered: the components of (V) are linked by multiple N—H...O hydrogen bonds to form a chain of rings; those of (VI) are linked into a three-dimensional framework by a combination of N—H...O, C—H...O and C—H...N hydrogen bonds and those of (VII), where the anion has a structure reminiscent of the picrate anion, are linked into a three-dimensional array by N—H...O and C—H...O hydrogen bonds. The hydrogensuccinate and hydrogenfumarate salts, C11H17N2O+·C4H5O4 − (VIII) and C11H17N2O+·C4H3O3 − (IX), respectively, are isomorphous, and both exhibit disorder in the anionic component: N—H...O and O—H...O hydrogen bonds link the ions into sheets, which are further linked by C—H...π(arene) interactions. The anion of the hydrogenmaleate salt, C11H17N2O+·C4H3O3 − (X), contains a very short and nearly symmetrical O...H...O hydrogen bond, and N—H...O hydrogen bonds link the anions into chains of rings. The ions in the trichloroacetate salt, C11H17N2O+·C2Cl3O2 − (XI), are linked into simple chains by N—H...O hydrogen bonds. In the hydrated chloranilate salt, 2C11H17N2O+·C6Cl2O4 2−·2H2O (XII), which crystallizes as a non-merohedral twin, the anion lies across a centre of inversion in space group P21/n, and a combination of N—H...O and O—H...O hydrogen bonds generates complex sheets. Comparisons are made with the structures of some related compounds.


IUCrData ◽  
2017 ◽  
Vol 2 (1) ◽  
Author(s):  
P. Seethalakshmi ◽  
C. Palanivel

In the title solvated compound, C24H17N5O4·C2H6OS, the solvent molecule, dimethyl sulfoxide, is linked to the title molecule by an N—H...O hydrogen bond. The pyridine ring adopts a twist-boat conformation. The isoxazole ring is inclined to the indoline ring system, the pyrimidine ring, and the phenyl ring by 82.31 (7), 10.41 (8) and 53.77 (10)°, respectively. There is an intramolecular C—H...π interaction present involving the phenyl ring and the indoline ring system. In the crystal, molecules are connected by two pairs of N—H...O hydrogen bonds, forming chains along theb-axis direction, and enclosingR22(8) andR22(14) ring motifs. The chains are linked by C—H...O and C—H...N hydrogen bonds and offset π–π interactions, between the pyrimidine and isoxazole rings of inversion-related molecules [centroid–centroid distance = 3.7140 (9) Å], forming a three-dimensional structure.


Author(s):  
Chayanna Harish Chinthal ◽  
Channappa N. Kavitha ◽  
Hemmige S. Yathirajan ◽  
Sabine Foro ◽  
Christopher Glidewell

Six 1-halobenzoyl-4-(2-methoxyphenyl)piperazines have been prepared using carbodiimide-mediated coupling reactions between halobenzoic acids and N-(2-methoxyphenyl)piperazine. The molecules of 1-(4-fluorobenzoyl)-4-(2-methoxyphenyl)piperazine, C18H19FN2O2 (I), are linked into a chain of rings by a combination of C—H...O and C—H...π(arene) hydrogen bonds. 1-(4-Chlorobenzoyl)-4-(2-methoxyphenyl)piperazine, C18H19ClN2O2 (II), crystallizes in the space group Pca21 with Z′ = 4 and it exhibits both pseudosymmetry and inversion twinning: a combination of six C—H...O and two C—H...π(arene) hydrogen bonds generate a three-dimensional assembly. In 1-(4-bromobenzoyl)-4-(2-methoxyphenyl)piperazine, C18H19BrN2O2 (III), which also crystallizes in space group Pca21 but with Z′ = 2, the bromobenzoyl unit in one of the molecules is disordered. Pseudosymmetry and inversion twinning are again present, and a combination of three C—H...O and one C—H...π(arene) hydrogen bonds generate a two-dimensional assembly. A single C—H...O hydrogen bond links the molecules of 1-(4-iodobenzoyl)-4-(2-methoxyphenyl)piperazine, C18H19IN2O2 (IV), into simple chains but in the isomeric 3-iodobenzoyl analogue (V), which crystallizes in space group P212121 with Z′ = 2, a two-dimensional assembly is generated by a combination of four C—H...O and two C—H...π(arene) hydrogen bonds; pseudosymmetry and inversion twinning are again present. A single C—H...O hydrogen bond links the molecules of 1-(2-fluorobenzoyl)-4-(2-methoxyphenyl)piperazine, C18H19FN2O2 (VI), into simple chains. Comparisons are made with the structures of some related compounds.


2012 ◽  
Vol 68 (8) ◽  
pp. o2546-o2546
Author(s):  
Shu Chen ◽  
Daxin Shi ◽  
Mingxing Liu ◽  
Jiarong Li

The title compound, C12H17N5O, was obtained by cyclocondensation of 2,4-diaminopyrimidine-5-carbonitrile with cycloheptanone. The tetrahydropyrimidine ring has a distorted boat conformation and the cycloheptane ring adopts a chair conformation. In the crystal, molecules are linkedviaN—H...O and N—H...N hydrogen bonds generating a three-dimensional network.


2001 ◽  
Vol 58 (1) ◽  
pp. 94-108 ◽  
Author(s):  
Craig J. Kelly ◽  
Janet M. S. Skakle ◽  
James L. Wardell ◽  
Solange M. S. V. Wardell ◽  
John N. Low ◽  
...  

Molecules of N-(4′-iodophenylsulfonyl)-4-nitroaniline, 4-O2NC6H4NHSO2C6H4I-4′ (1), are linked by three-centre I...O2N interactions into chains and these chains are linked into a three-dimensional framework by C—H...O hydrogen bonds. In the isomeric N-(4′-nitrophenylsulfonyl)-4-iodoaniline, 4-IC6H4NHSO2C6H4NO2-4′ (2), the chains generated by the I...O2N interactions are again linked into a three-dimensional framework by C—H...O hydrogen bonds. Molecules of N,N-bis(3′-nitrophenylsulfonyl)-4-iodoaniline, 4-IC6H4N(SO2C6H4NO2-3′)2 (3), lie across twofold rotation axes in space group C2/c and they are linked into chains by paired I...O=S interactions: these chains are linked into sheets by a C—H...O hydrogen bond, and the sheets are linked into a three-dimensional framework by aromatic π...π stacking interactions. In N-(4′-iodophenylsulfonyl)-3-nitroaniline, 3-O2NC6H4NHSO2C6H4I-4′ (4), there are R^2_2(8) rings formed by hard N—H...O=S hydrogen bonds and R^2_2(24) rings formed by two-centre I...nitro interactions, which together generate a chain of fused rings: the combination of a C—H...O hydrogen bond and aromatic π...π stacking interactions links the chains into sheets. Molecules of N-(4′-iodophenylsulfonyl)-4-methyl-2-nitroaniline, 4-CH3-2-O2NC6H3NHSO2C6H4I-4′ (5), are linked by N—H...O=S and C—H...O(nitro) hydrogen bonds into a chain containing alternating R^2_2(8) and R^2_2(10) rings, but there are no I...O interactions of either type. There are two molecules in the asymmetric unit of N-(4′-iodophenylsulfonyl)-2-nitroaniline, 2-O2NC6H4NHSO2C6H4I-4′ (6), and the combination of an I...O=S interaction and a hard N—H...O(nitro) hydrogen bond links the two types of molecule to form a cyclic, centrosymmetric four-component aggregate. C—H...O hydrogen bonds link these four-molecule aggregates to form a molecular ladder. Comparisons are made with structures retrieved from the Cambridge Structural Database.


Author(s):  
Ponnusamy Poornima Devi ◽  
Doraisamyraja Kalaivani

In the anion of the title hydrated molecular salt, C4H8N3O+·C12H9N4O7−·H2O [systematic name: 2-amino-1-methyl-4-oxo-4,5-dihydro-1H-imidazol-3-ium 5-(2,4-dinitrophenyl)-1,3-dimethyl-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olate monohydrate], the 2,4-dinitrophenyl ring is inclined to the mean plane of the pyrimidine ring [r.m.s. deviation = 0.37 Å] by 43.24 (8)°. The five-membered ring of the creatininium cation (2-amino-1-methyl-4-oxo-4,5-dihydro-1H-imidazol-3-ium) is essentially planar with an r.m.s. deviation of 0.015 Å. In the crystal, the anions and cations are linkedviaN—H...O hydrogen bonds, forming sheets parallel to theabplane. The sheets are linkedviaO—H...O hydrogen bonds involving the water molecule, forming a three-dimensional framework. Within the framework, there are C—H...O hydrogen bonds present. The title molecular salt displays anticonvulsant and hypnotic activities.


Author(s):  
Scott A. Steiger ◽  
Chun Li ◽  
Christina Gates ◽  
Nicholas R. Natale

The title compound I, 2,2′-[(2-nitrophenyl)methylene]bis(3-hydroxy-5,5-dimethylcyclohex-2-enone), C23H27NO6, features a 1,3-ketone–enol conformation which is stabilized by two intramolecular hydrogen bonds. The most prominent intermolecular interactions in compound I are C—H...O hydrogen bonds, which link molecules into a two-dimensional network parallel to the (001) plane and a chain perpendicular to (1\overline{1}1). Both title compounds II, ethyl 4-(4-hydroxy-3,5-dimethoxyphenyl)-2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate, C23H29NO6, and III, ethyl 4-(anthracen-9-yl)-2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate, C29H29NO3, share the same structural features, such as a shallow boat conformation of the dihydropyridine group and an orthogonal aryl group attached to the dihydropyridine. Intermolecular N—H...O bonding is present in the crystal packing of both compound II and III.


2013 ◽  
Vol 69 (12) ◽  
pp. o1781-o1781 ◽  
Author(s):  
M. Umadevi ◽  
V. Saravanan ◽  
R. Yamuna ◽  
A. K. Mohanakrishnan ◽  
G. Chakkaravarthi

In the title compound, C18H16ClNO2S, the indole ring system forms a dihedral angle of 75.07 (8)° with the phenyl ring. The molecular structure is stabilized by a weak intramolecular C—H...O hydrogen bond. In the crystal, molecules are linked by weak C—H...O hydrogen bonds, forming a chain along [10-1]. C—H...π interactions are also observed, leading to a three-dimensional network.


2019 ◽  
Vol 75 (6) ◽  
pp. 650-656
Author(s):  
Lina M. Acosta Quintero ◽  
Alirio Palma ◽  
Justo Cobo ◽  
Christopher Glidewell

Reaction of 2-allyl-N-benzyl-4-fluoroaniline or 2-allyl-N-benzyl-4-chloroaniline with 98% sulfuric acid leads to the concurrent formation of halogeno-substituted 11-ethyl-6,11-dihydrodibenzo[b,e]azepines, (II), and halogeno-substituted 11-methyl-5,6,11,12-tetrahydrodibenzo[b,f]azocines, (III), in each case in (II):(III) molar ratios of ca 2:1. Further reaction of (II) leads to ethyl 13-ethyl-2-halogeno-4-oxo-8,13-dihydro-4H-benzo[5,6]azepino[3,2,1-ij]quinoline-5-carboxylate, while acetylation of (III) gives the corresponding N-acetyl derivatives. The dibenzo[b,e]azepine and dibenzo[b,f]azocine ring systems are of importance in forming the core of a variety of bioactive compounds. In ethyl 13-ethyl-2-fluoro-4-oxo-8,13-dihydro-4H-benzo[5,6]azepino[3,2,1-ij]quinoline-5-carboxylate, C22H20FNO3, (IVa), the azepine ring adopts a conformation close to the twist-boat form, and the molecules are linked into a three-dimensional framework structure by a combination of C—H...O and C—H...π(arene) hydrogen bonds. The azocine ring in 5-acetyl-2-chloro-11-methyl-5,6,11,12-tetrahydrobenzo[b,f]azocine, C18H18ClNO, (Vb), adopts the boat–boat conformation and the molecules are again linked by C—H...O and C—H...π(arene) hydrogen bonds, but this time form a sheet structure.


Sign in / Sign up

Export Citation Format

Share Document