共查询到20条相似文献,搜索用时 31 毫秒
1.
Scott A. Steiger Anthony J. Monacelli Chun Li Janet L. Hunting Nicholas R. Natale 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(8):790-795
Three quinolone compounds were synthesized and crystallized in an effort to study the structure–activity relationship of these calcium‐channel antagonists. In all three quinolones, viz. ethyl 4‐(4‐bromophenyl)‐2,7,7‐trimethyl‐5‐oxo‐1,4,5,6,7,8‐hexahydroquinoline‐3‐carboxylate, (I), ethyl 4‐(3‐bromophenyl)‐2,7,7‐trimethyl‐5‐oxo‐1,4,5,6,7,8‐hexahydroquinoline‐3‐carboxylate, (II), and ethyl 4‐(2‐bromophenyl)‐2,7,7‐trimethyl‐5‐oxo‐1,4,5,6,7,8‐hexahydroquinoline‐3‐carboxylate, (III), all C21H24BrNO3, common structural features such as a flat boat conformation of the 1,4‐dihydropyridine (1,4‐DHP) ring, an envelope conformation of the fused cyclohexanone ring and a bromophenyl ring at the pseudo‐axial position and orthogonal to the 1,4‐DHP ring are retained. However, due to the different packing interactions in each compound, halogen bonds are observed in (I) and (III). Compound (III) crystallizes with two molecules in the asymmetric unit. All of the prepared derivatives satisfy the basic structural requirements to possess moderate activity as calcium‐channel antagonists. 相似文献
2.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(3):325-331
Aminopyrimidine derivatives are biologically important as they are components of nucleic acids and drugs. The crystals of two new salts, namely cytosinium 6‐chloronicotinate monohydrate, C4H6N3O+·C6H3ClNO2−·H2O, ( I ), and 5‐bromo‐6‐methylisocytosinium hydrogen sulfate (or 2‐amino‐5‐bromo‐4‐oxo‐6‐methylpyrimidinium hydrogen sulfate), C5H7BrN3O+·HSO4−, ( II ), have been prepared and characterized by single‐crystal X‐ray diffraction. The pyrimidine ring of both compounds is protonated at the imine N atom. In hydrated salt ( I ), the primary R22(8) ring motif (supramolecular heterosynthon) is formed via a pair of N—H…O(carboxylate) hydrogen bonds. The cations, anions and water molecule are hydrogen bonded through N—H…O, N—H…N, O—H…O and C—H…O hydrogen bonds, forming R22(8), R32(7) and R55(21) motifs, leading to a hydrogen‐bonded supramolecular sheet structure. The supramolecular double sheet structure is formed via water–carboxylate O—H…O hydrogen bonds and π–π interactions between the anions and the cations. In salt ( II ), the hydrogen sulfate ions are linked via O—H…O hydrogen bonds to generate zigzag chains. The aminopyrimidinium cations are embedded between these zigzag chains. Each hydrogen sulfate ion bridges two cations via pairs of N—H…O hydrogen bonds and vice versa, generating two R22(8) ring motifs (supramolecular heterosynthon). The cations also interact with one another via halogen–halogen (Br…Br) and halogen–oxygen (Br…O) interactions. 相似文献
3.
Alexander S. Lyakhov Ludmila S. Ivashkevich Vladimir L. Survilo Alexander M. Kipnis Tatjana V. Trukhachova 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(9):o365-o368
The title compounds, C8H11NO, (I), and 2C8H12NO+·C4H4O42−, (II), both crystallize in the monoclinic space group P21/c. In the crystal structure of (I), intermolecular O—H...N hydrogen bonds combine the molecules into polymeric chains extending along the c axis. The chains are linked by C—H...π interactions between the methylene H atoms and the pyridine rings into polymeric layers parallel to the ac plane. In the crystal structure of (II), the succinate anion lies on an inversion centre. Its carboxylate groups interact with the 2‐ethyl‐3‐hydroxy‐6‐methylpyridinium cations via intermolecular N—H...O hydrogen bonds with the pyridine ring H atoms and O—H...O hydrogen bonds with the hydroxy H atoms to form polymeric chains, which extend along the [01] direction and comprise R44(18) hydrogen‐bonded ring motifs. These chains are linked to form a three‐dimensional network through nonclassical C—H...O hydrogen bonds between the pyridine ring H atoms and the hydroxy‐group O atoms of neighbouring cations. π–π interactions between the pyridine rings and C—H...π interactions between the methylene H atoms of the succinate anion and the pyridine rings are also present in this network. 相似文献
4.
Krishnan Ravikumar Balasubramanian Sridhar Venkatasubramanian Hariharakrishnan Awadesh Narain Singh 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(11):o475-o480
The structures of the novel triazolobenzothiazines 2,4‐dihydro‐1H‐benzo[b][1,2,4]triazolo[4,3‐d][1,4]thiazin‐1‐one (IDPH‐791), C9H7N3OS, (I), a potential muscle relaxant, its benzoyl derivative, 2‐(2‐oxo‐2‐phenylethyl)‐2,4‐dihydro‐1H‐benzo[b][1,2,4]triazolo[4,3‐d][1,4]thiazin‐1‐one, C20H17N3O4S, (II), and the β‐keto ester derivative, ethyl 3‐oxo‐2‐(1‐oxo‐2,4‐dihydro‐1H‐benzo[b][1,2,4]triazolo[4,3‐d][1,4]thiazin‐2‐yl)‐3‐phenylpropanoate, C17H13N3O2S, (III), are the first examples of benzothiazine‐fused triazoles in the crystallographic literature. The heterocyclic thiazine rings in all three structures adopt a distorted half‐chair conformation. Compound (III) exists in the trans‐β‐diketo form. Other than N—H...O hydrogen bonds in (I) forming dimers, no formal intermolecular hydrogen bonds are involved in the crystal packing of any of the three structures, which is dominated by C—H...O/N and π–π stacking interactions. 相似文献
5.
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
6.
Edwar Corts Rodrigo Abonía Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(1):77-81
In methyl 4‐(4‐chloroanilino)‐3‐nitrobenzoate, C14H11ClN2O4, (I), there is an intramolecular N—H...O hydrogen bond and the intramolecular distances provide evidence for electronic polarization of the o‐quinonoid type. The molecules are linked into sheets built from N—H...O, C—H...O and C—H...π(arene) hydrogen bonds, together with an aromatic π–π stacking interaction. The molecules of methyl 1‐benzyl‐2‐(4‐chlorophenyl)‐1H‐benzimidazole‐5‐carboxylate, C22H17ClN2O2, (II), are also linked into sheets, this time by a combination of C—H...π(arene) hydrogen bonds and aromatic π–π stacking interactions. 相似文献
7.
John N. Low Justo Cobo Ana Snchez Jorge Trilleras Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(5):o287-o291
Both 6‐(1H‐indol‐3‐yl)‐3‐methyl‐4‐(4‐methylphenyl)‐1‐phenyl‐1H‐pyrazolo[3,4‐b]pyridine‐5‐carbonitrile and 6‐(1H‐indol‐3‐yl)‐3‐methyl‐4‐(4‐methoxyphenyl)‐1‐phenyl‐1H‐pyrazolo[3,4‐b]pyridine‐5‐carbonitrile crystallize from dimethylformamide solutions as stoichiometric 1:1 solvates, viz. C29H21N5·C3H7NO, (I), and C29H21N5O·C3H7NO, (II), respectively; however, 6‐(1H‐indol‐3‐yl)‐3‐methyl‐1‐phenyl‐4‐(3,4,5‐trimethoxyphenyl)‐1H‐pyrazolo[3,4‐b]pyridine‐5‐carbonitrile, C31H25N5O3, (III), crystallizes in the unsolvated form. The heterocyclic components of (I) are linked by C—H...π(arene) hydrogen bonds to form cyclic centrosymmetric dimers, from which the solvent molecules are pendent, linked by N—H...O hydrogen bonds. In (II), the heterocyclic components are linked by a combination of C—H...N and C—H...π(arene) hydrogen bonds into chains containing two types of centrosymmetric ring, and the pendent solvent molecules are linked to these chains by N—H...O hydrogen bonds. Molecules of (III) are linked into simple C(12) chains by an N—H...O hydrogen bond, and these chains are weakly linked into pairs by an aromatic π–π stacking interaction. 相似文献
8.
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
9.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(9):743-748
In the salt trimethoprimium ferrocenecarboxylate [systematic name: 2,4‐diamino‐5‐(3,4,5‐trimethoxybenzyl)pyrimidin‐1‐ium ferrocene‐1‐carboxylate], (C14H19N4O3)[Fe(C5H5)(C6H4O2)], (I), of the antibacterial compound trimethoprim, the carboxylate group interacts with the protonated aminopyrimidine group of trimethoprim via two N—H…O hydrogen bonds, generating a robust R 22(8) ring motif (heterosynthon). However, in the cocrystal 4‐amino‐5‐chloro‐2,6‐dimethylpyrimidine–ferrocene‐1‐carboxylic acid (1/1), [Fe(C5H5)(C6H5O2)]·C6H8ClN3, (II), the carboxyl–aminopyrimidine interaction [R 22(8) motif] is absent. The carboxyl group interacts with the pyrimidine ring via a single O—H…N hydrogen bond. The pyrimidine rings, however, form base pairs via a pair of N—H…N hydrogen bonds, generating an R 22(8) supramolecular homosynthon. In salt (I), the unsubstituted cyclopentadienyl ring is disordered over two positions, with a refined site‐occupation ratio of 0.573 (10):0.427 (10). In this study, the two five‐membered cyclopentadienyl (Cp) rings of ferrocene are in a staggered conformation, as is evident from the C…Cg …Cg …C pseudo‐torsion angles, which are in the range 36.13–37.53° for (I) and 22.58–23.46° for (II). Regarding the Cp ring of the minor component in salt (I), the geometry of the ferrocene ring is in an eclipsed conformation, as is evident from the C…Cg …Cg …C pseudo‐torsion angles, which are in the range 79.26–80.94°. Both crystal structures are further stabilized by weak π–π interactions. 相似文献
10.
Anthony Linden Rahime imek Miyase Gündüz Cihat afak 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(12):o731-o734
The title compounds, C20H21F2NO3 and C21H23F2NO3, respectively, belong to a class of 1,4‐dihydropyridines whose members sometimes display calcium modulatory properties. The 1,4‐dihydropyridine rings have the usual shallow boat conformation. In each structure, the 2,3‐difluorophenyl ring is oriented such that the fluoro substituents are in a synperiplanar orientation with respect to the 1,4‐dihydropyridine ring plane and the oxocyclohexene ring has a slightly distorted envelope conformation. Both structures exhibit the same intermolecular N—H⋯O hydrogen‐bonding motif, in which the molecules are linked into chains by interactions involving the carbonyl O atom of the oxocyclohexene ring. 相似文献
11.
Cheng‐Bing Ma Hui Chen Ming‐Qiang Hu Chang‐Neng Chen 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(2):m59-m61
In the title compound, [Mn(C5H2N2O4)(C12H9N3)2]·H2O, the MnII centre is surrounded by three bidentate chelating ligands, namely, one 6‐oxido‐2‐oxo‐1,2‐dihydropyrimidine‐5‐carboxylate (or uracil‐5‐carboxylate, Huca2−) ligand [Mn—O = 2.136 (2) and 2.156 (3) Å] and two 2‐(2‐pyridyl)‐1H‐benzimidazole (Hpybim) ligands [Mn—N = 2.213 (3)–2.331 (3) Å], and it displays a severely distorted octahedral geometry, with cis angles ranging from 73.05 (10) to 105.77 (10)°. Intermolecular N—H...O hydrogen bonds both between the Hpybim and the Huca2− ligands and between the Huca2− ligands link the molecules into infinite chains. The lattice water molecule acts as a hydrogen‐bond donor to form double O...H—O—H...O hydrogen bonds with the Huca2− O atoms, crosslinking the chains to afford an infinite two‐dimensional sheet; a third hydrogen bond (N—H...O) formed by the water molecule as a hydrogen‐bond acceptor and a Hpybim N atom further links these sheets to yield a three‐dimensional supramolecular framework. Possible partial π–π stacking interactions involving the Hpybim rings are also observed in the crystal structure. 相似文献
12.
Jairo Quiroga Dayana Pantoja Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(8):884-887
In the title compound, C31H29N3O2, the reduced pyridine ring adopts a conformation intermediate between the envelope and half‐chair forms. The aryl rings of the benzyl and phenyl substituents are nearly parallel and overlap, indicative of an intramolecular π–π stacking interaction. A combination of two C—H...O hydrogen bonds and one C—H...N hydrogen bond links the molecules into a bilayer having tert‐butyl groups on both faces.<!?tpb=19.5pt> 相似文献
13.
Mohammad Ghadermazi Marilyn M. Olmstead Jafar Attar Gharamaleki Shahideh Rostami 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(4):o134-o138
Two related proton‐transfer compounds, namely piperazine‐1,4‐diium 4‐oxo‐4H‐pyran‐2,6‐dicarboxylate monohydrate, C4H12N22+·C7H2O62−·H2O or (pipzH2)(cdo)·H2O, (I), and piperazine‐1,4‐diium bis(6‐carboxy‐4‐oxo‐4H‐pyran‐2‐carboxylate), C4H12N22+·2C7H3O6− or (pipzH2)(cdoH)2, (II), were obtained by the reaction of 4‐oxo‐4H‐pyran‐2,6‐dicarboxylic acid (chelidonic acid, cdoH2) and piperazine (pipz). In (I), both carboxyl H atoms of chelidonic acid have been transferred to piperazine to form the piperazine‐1,4‐diium ion. The structure is a monohydrate. All potential N—H donors are involved in N—H...O hydrogen bonds. The water molecule spans two anions via the 4‐oxo group of the pyranose ring and a carboxylate O atom. The hydrogen‐bonding motif is essentially two‐dimensional. The structure is a pseudomerohedral twin. In the asymmetric unit of (II), the anion consists of monodeprotonated chelidonic acid, while the piperazine‐1,4‐diium cation is located on an inversion centre. The single carboxyl H atom is disordered in two respects. Firstly, the disordered H atom is shared equally by both carboxylic acid groups. Secondly, the H atom is statistically disordered between two positions on either side of a centre of symmetry and is engaged in a very short hydrogen‐bonding interaction; the relevant O...O distances are 2.4549 (11) and 2.4395 (11) Å, and the O—H...O angles are 177 (6) and 177 (5)°, respectively. Further hydrogen bonding of the type N—H...O places the (pipzH2)2+ cations in pockets formed by the chains of (cdoH)− anions. In contrast with (I), the (pipzH2)2+ cations form hydrogen‐bonding arrays that are perpendicular to the anions, yielding a three‐dimensional hydrogen‐bonding motif. The structures of both (I) and (II) also feature π–π stacking interactions between aromatic rings. 相似文献
14.
Olivier Vallat Ana‐Maria Buciumas Reinhard Neier Helen Stoeckli‐Evans 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(4):o171-o175
The title compounds, rac‐(1′R,2R)‐tert‐butyl 2‐(1′‐hydroxyethyl)‐3‐(2‐nitrophenyl)‐5‐oxo‐2,5‐dihydro‐1H‐pyrrole‐1‐carboxylate, C17H20N2O6, (I), rac‐(1′S,2R)‐tert‐butyl 2‐[1′‐hydroxy‐3′‐(methoxycarbonyl)propyl]‐3‐(2‐nitrophenyl)‐5‐oxo‐2,5‐dihydro‐1H‐pyrrole‐1‐carboxylate, C20H24N2O8, (II), and rac‐(1′S,2R)‐tert‐butyl 2‐(4′‐bromo‐1′‐hydroxybutyl)‐5‐oxo‐2,5‐dihydro‐1H‐pyrrole‐1‐carboxylate, C13H20BrNO4, (III), are 5‐hydroxyalkyl derivatives of tert‐butyl 2‐oxo‐2,5‐dihydropyrrole‐1‐carboxylate. In all three compounds, the tert‐butoxycarbonyl (Boc) unit is orientated in the same manner with respect to the mean plane through the 2‐oxo‐2,5‐dihydro‐1H‐pyrrole ring. The hydroxyl substituent at one of the newly created chiral centres, which have relative R,R stereochemistry, is trans with respect to the oxo group of the pyrrole ring in (I), synthesized using acetaldehyde. When a larger aldehyde was used, as in compounds (II) and (III), the hydroxyl substituent was found to be cis with respect to the oxo group of the pyrrole ring. Here, the relative stereochemistry of the newly created chiral centres is R,S. In compound (I), O—H...O hydrogen bonding leads to an interesting hexagonal arrangement of symmetry‐related molecules. In (II) and (III), the hydroxyl groups are involved in bifurcated O—H...O hydrogen bonds, and centrosymmetric hydrogen‐bonded dimers are formed. The Mukaiyama crossed‐aldol‐type reaction was successful when using the 2‐nitrophenyl‐substituted hydroxypyrrole, or the unsubstituted hydroxypyrrole, and boron trifluoride diethyl ether as catalyst. The synthetic procedure leads to a syn configuration of the two newly created chiral centres in all three compounds. 相似文献
15.
John N. Low Justo Cobo Silvia Cruz Jairo Quiroga Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(3):o191-o193
Molecules of the title compound, C15H21N3O3S, have a markedly polarized electronic structure; the carbocyclic ring adopts an envelope conformation and the overall molecular conformation appears to be controlled by two intramolecular hydrogen bonds, one each of the O—H⋯O and N—H⋯O types. The molecules are linked into C(6) chains by an intermolecular N—H⋯O hydrogen bond, and pairs of these hydrogen‐bonded chains are linked by a π–π stacking interaction. 相似文献
16.
Yuan‐Zhen Ke Leng‐Feng Zheng Jian‐Hai Luo Xi‐He Huang Chang‐Cang Huang 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(8):m343-m345
The title complex, [Co(C15H12N3O2S)2], consists of an octahedrally coordinated CoII ion, with two crystallographically independent 1,4‐dibenzoylthiosemicarbazidate ligands in a tridentate mer coordination [Co—O = 2.064 (3)–2.132 (3) Å and Co—N = 2.037 (3)–2.043 (3) Å]. There are intermolecular N—H...S hydrogen bonds involving one ligand and strong π–π stacking interactions involving the other ligand, resulting in a three‐dimensional supramolecular framework. The hydrogen bonds and π–π interactions, as well as different intramolecular aryl–benzamide H—C...H(—N) distances, give rise to a difference in conformation between the two ligands. 相似文献
17.
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
18.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(7):531-535
3‐Aminocarbonyl‐1‐benzylpyridinium bromide (N‐benzylnicotinamide, BNA), C13H13N2O+·Br−, (I), and 1‐benzyl‐1,4‐dihydropyridine‐3‐carboxamide (N‐benzyl‐1,4‐dihydronicotinamide, rBNA), C13H14N2O, (II), are valuable model compounds used to study the enzymatic cofactors NAD(P)+ and NAD(P)H. BNA was crystallized successfully and its structure determined for the first time, while a low‐temperature high‐resolution structure of rBNA was obtained. Together, these structures provide the most detailed view of the reactive portions of NAD(P)+ and NAD(P)H. The amide group in BNA is rotated 8.4 (4)° out of the plane of the pyridine ring, while the two rings display a dihedral angle of 70.48 (17)°. In the rBNA structure, the dihydropyridine ring is essentially planar, indicating significant delocalization of the formal double bonds, and the amide group is coplanar with the ring [dihedral angle = 4.35 (9)°]. This rBNA conformation may lower the transition‐state energy of an ene reaction between a substrate double bond and the dihydropyridine ring. The transition state would involve one atom of the double bond binding to the carbon ortho to both the ring N atom and the amide substituent of the dihydropyridine ring, while the other end of the double bond accepts an H atom from the methylene group para to the N atom. 相似文献
19.
Anthony Linden Miyase G. Gündüz Rahime imek Cihat afak 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):o227-o230
A mixture of the RR/SS and RS/SR diastereoisomeric pairs of methyl 4‐(2,4‐dichlorophenyl)‐2,7‐dimethyl‐5‐oxo‐1,4,5,6,7,8‐hexahydroquinoline‐3‐carboxylate, C19H19Cl2NO3, forms cocrystals in which there is one unique molecule in the asymmetric unit, but the molecule displays disorder in the region of the 7‐position of the quinoline ring system as a result of the random occurrence of the diastereoisomers at the same crystallographic site. A similar arrangement exists in the monohydrate cocrystals that form from a mixture of the RR/SS and RS/SR diastereoisomeric pairs of methyl 4‐(2,4‐dichlorophenyl)‐2‐methyl‐7‐phenyl‐5‐oxo‐1,4,5,6,7,8‐hexahydroquinoline‐3‐carboxylate monohydrate, C24H21Cl2NO3·H2O. These compounds belong to a class of 1,4‐dihydropyridines whose members have calcium modulatory properties. The 1,4‐dihydropyridine rings have the usual shallow boat conformation. In each structure, the 2,4‐dichlorophenyl ring is oriented such that the 2‐chloro substituent is in a synperiplanar orientation with respect to the 1,4‐dihydropyridine ring plane. In each crystal structure, the molecules are linked into chains by N—H⋯O hydrogen‐bonding interactions. 相似文献
20.
Ammasai Karthikeyan Robert Swinton Darious Packianathan Thomas Muthiah Franc Perdih 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(11):985-990
Two novel cocrystals of the N(7)—H tautomeric form of N6‐benzoyladenine (BA), namely N6‐benzoyladenine–3‐hydroxypyridinium‐2‐carboxylate (3HPA) (1/1), C12H9N5O·C6H5NO3, (I), and N6‐benzoyladenine–DL‐tartaric acid (TA) (1/1), C12H9N5O·C4H6O6, (II), are reported. In both cocrystals, the N6‐benzoyladenine molecule exists as the N(7)—H tautomer, and this tautomeric form is stabilized by intramolecular N—H...O hydrogen bonding between the benzoyl C=O group and the N(7)—H hydrogen on the Hoogsteen site of the purine ring, forming an S(7) motif. The dihedral angle between the adenine and phenyl planes is 0.94 (8)° in (I) and 9.77 (8)° in (II). In (I), the Watson–Crick face of BA (N6—H and N1; purine numbering) interacts with the carboxylate and phenol groups of 3HPA through N—H...O and O—H...N hydrogen bonds, generating a ring‐motif heterosynthon [graph set R22(6)]. However, in (II), the Hoogsteen face of BA (benzoyl O atom and N7; purine numbering) interacts with TA (hydroxy and carbonyl O atoms) through N—H...O and O—H...O hydrogen bonds, generating a different heterosynthon [graph set R22(4)]. Both crystal structures are further stabilized by π–π stacking interactions. 相似文献