research communications
of creatininium 5-(2,4-dinitrophenyl)-1,3-dimethylbarbiturate monohydrate: a potential anticonvulsant agent
aPG and Research Department of Chemistry, Seethalakshmi Ramaswami College, Tiruchirappalli 620 002, Tamil Nadu, India
*Correspondence e-mail: kalaivbalaj@yahoo.co.in
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 linked via N—H⋯O hydrogen bonds, forming sheets parallel to the ab plane. The sheets are linked via O—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.
Keywords: crystal structure; creatinine; creatininium; 5-(2,4-dinitrophenyl)-N,N-dimethylbarbiturate; anticonvulsant activity; hydrogen bonding.
CCDC reference: 1060400
1. Chemical context
Creatinine is a breakdown product of creatine phosphate during metabolic activity in living systems (Ueda, 1964). Creatinine exists in both the amino and the imino tautomeric forms. Due to the presence of various groups, such as CH3, CH2, NH, NH2 and C=O, it can form C—H⋯O, N—H⋯O and O—H⋯O hydrogen bonds with other molecules. are pyrimidine derivatives which exhibit their action by modulating the ion channels. Pyrimidine and its derivatives have been shown to be effective medications (Brown, 1962; Gauthier et al., 1963; Shorvon, 2004; Jain et al., 2006; Tripathi, 2009). In this context, a number of pharmacologically active molecular salts with different barbiturate entities and cationic counter parts have been described (see for example: Rajamani & Kalaivani, 2015; Gomathi & Kalaivani, 2015). Herein, we describe the synthesis and of the title molecular salt, which has been shown to exhibit anticonvulsant and hypnotic activities.
2. Structural commentary
The structure of the title molecular salt is illustrated in Fig. 1. The bond lengths and bond angles are normal and comparable with those observed in related (Sridevi & Kalaivani, 2012; Gunaseelan & Doraisamyraja, 2014). The five-membered ring of the creatininium (2-amino-1-methyl-4-oxo-4,5-dihydro-1H-imidazol-3-ium) cation is essentially planar with an r.m.s. deviation of 0.015 Å. In the anion, 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 nitro group ortho with respect to ring junction is inclined to the benzene ring to which it is attached by 37.6 (2)°, while the nitro group para with respect to the ring junction is inclined to the benzene ring by 7.4 (3)°. The different dihedral angles imply that though two nitro groups are involved in delocalizing the negative charge on the oxygen atom of barbiturate ion, the para nitro group is more effective than the ortho nitro group.
3. Supramolecular features
In the crystal, the anion and cation are linked via N—H⋯O hydrogen bonds, forming sheets parallel to the ab plane (Fig. 2 and Table 1). The sheets are linked via O—H⋯O hydrogen bonds involving the water molecule, forming a three-dimensional framework (Fig. 3 and Table 1). Within the framework, there are C—H⋯O hydrogen bonds present (Table 1).
4. Database survey
A search of the Cambridge Structural Database (CSD, Version 53.7, last update February 2016; Groom & Allen, 2014) for the title anion as sub-structure gave 17 hits, of which five involve 5-(2,4-dinitrophenyl)-1,3-dimethylbarbiturate and organic cations. They include the molecular salts of 3-aminopyridinium (CSD refcode QUNRAU; Kalaivani & Sridevi, 2015a), 4-aminopyridinium (QUNROI; Kalaivani & Sridevi, 2015b), N,N-diethylethanolammonium (QUNRUO; Kalaivani & Sridevi, 2015c), trimethylammonium (CORWUD; Gunaseelan & Doraisamyraja, 2014) and 2-methylpyridinium (YAVSOF; Sridevi & Kalaivani, 2012). In the anions, the benzene ring is inclined to the mean plane of the pyrimidine ring by dihedral angles varying from ca 39.0 to 50.5°. The ortho nitro group is inclined to the benzene ring by dihedral angles varying from ca 2.4 to 5.8°, and the para nitro group is inclined to the benzene ring by a much larger angle, varying between ca 37.2 and 42.6°. Similar observations were made for the conformation of the barbiturate anion in the title molecular salt.
5. Biological activity
Epilepsy (convulsion) is one of the most common neurodegenerative disorder affecting at least 50 million people worldwide. Brain dysfunction due to different causes leads to epilepsy (Fisher et al., 2005). have a pyrimidone ring system. From their introduction into clinical practice at the beginning of the 20th century until recent years, they have occupied a vital place in the pharmacopoeia as CNS drugs (Yadav, 2004). The anticonvulsant activity of the synthesized barbiturate has been measured by employing the Maximal Electro Shock method (Kulkarni, 1999). In the present investigation, the title molecular salt reduces the clonus phase of convulsion to a greater extent than other phases of convulsion (flexion, extension and stupor) even at low dosage (25 mg kg−1) and hence may be used in the future for controlling myoclonic epilepsy of infants. The therapeutic dose induces hypnosis in albino mice. tests have also been carried out according to OECD guidelines on albino mice (LD50 >1000 mg kg −1; falls under class 4). The animals did not show any indication of behavioural changes after testing with the title molecular salt. The high safety margin reveals its significance as a potential anticonvulsant agent.
6. Synthesis and crystallization
Dinitrochlorobenzene (2.02 g, 0.01 mol) was dissolved in 20 ml of absolute alcohol. To this 1.56 g (0.01mol) of 1,3-dimethylbarbituric acid was added and the temperature of the mixture was raised to 323 K. To this mixture 1.13 g (0.01 mol) of creatinine in 20 ml of absolute alcohol was added. This mixture was shaken well for 2–5 h and kept as such at 298 K for 2 d. On standing, a maroon-red-coloured solid came out from the solution. The solid was ground to a fine powder, washed with absolute alcohol and dried with ether and then recrystallized from absolute alcohol. The solution was left to stand and maroon-red block-shaped crystals were obtained after two weeks. The crystals were harvested and air dried (yield: 80%; m.p. 483 K).
7. Refinement
Crystal data, data collection and structure . The NH H atoms were located from a difference Fourier map and freely refined. The water molecule H atoms were also located from a difference Fourier map and refined with Uiso(H) = 1.5Ueq(O). The C-bound H atoms were included in calculated positions and treated as riding atoms: C—H = 0.93–0.97 Å with Uiso(H) = 1.5Ueq(C-methyl) and 1.2Ueq(C) for other H atoms.
details are summarized in Table 2
|
Supporting information
CCDC reference: 1060400
10.1107/S2056989016005247/su5291sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2056989016005247/su5291Isup2.hkl
Creatinine is a breakdown product of creatine phosphate during metabolic activity in living systems (Ueda, 1964). Creatinine exists in both the amino and the imino tautomeric forms. Due to the presence of various functional groups such as CH3, CH2, NH, NH2 and C═O, it can form C—H···O, N—H···O and O—H···O hydrogen bonds with other molecules. are pyrimidine derivatives which exhibit their action by modulating the ion channel. Pyrimidine and its derivatives have been shown to be effective medications (Brown, 1962; Gauthier et al., 1963; Shorvon, 2004; Jain et al., 2006; Tripathi, 2009). In this context, a number of active molecular salts with different barbiturate entities and cationic counter parts have been described (see for example: Rajamani & Kalaivani, 2015; Gomathi & Kalaivani, 2015). Herein, we describe the synthesis and of the title molecular salt, which has been shown to exhibit anticonvulsant and hypnotic activities.
The structure of the title molecular salt is illustrated in Fig. 1. The bond lengths and bond angles are normal and comparable with those observed in related
(Sridevi & Kalaivani, 2012; Gunaseelan & Doraisamyraja, 2014). The five-membered ring of the creatininium (2-amino-1-methyl-4-oxo-4,5-dihydro-1H-imidazol-3-ium) cation is planar with an r.m.s. deviation of 0.015 Å. In the anion, 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 nitro group ortho with respect to ring junction is inclined to the benzene ring to which it is attached by 37.6 (2)°, while the nitro group para with respect to the ring junction is inclined to the benzene ring by 7.4 (3)°. The different dihedral angles imply that though two nitro groups are involved in delocalizing the negative charge on the oxygen atom of barbiturate ion, the para nitro group is more effective than the ortho nitro group.In the crystal, the anion and cation are linked via N—H···O hydrogen bonds, forming sheets parallel to the ab plane (Fig. 2 and Table 1). The sheets are linked via O—H···O hydrogen bonds involving the water molecule, forming a three-dimensional framework (Fig. 3 and Table 1). Within the framework, there are C—H···O hydrogen bonds present (Table 1).
A search of the Cambridge Structural Database (CSD, V53.7, last update February 2016; Groom & Allen, 2014) for the title anion as sub-structure gave 17 hits, of which five involve 5-(2,4-dinitrophenyl)-1,3-dimethylbarbiturate and organic cations. They include the molecular salts of 3-aminopyridinium (CSD refcode QUNRAU; Kalaivani & Sridevi, 2015a), 4-aminopyridinium (QUNROI; Kalaivani & Sridevi, 2015b), N,N-diethylethanolammonium (QUNRUO; Kalaivani & Sridevi, 2015c), trimethylammonium (CORWUD; Gunaseelan & Doraisamyraja, 2014) and 2-methylpyridinium (YAVSOF; Sridevi & Kalaivani, 2012). In the anions, the benzene ring is inclined to the mean plane of the pyrimidine ring by dihedral angles varying from ca 39.0 to 50.5°. The ortho nitro group is inclined to the benzene ring by dihedral angles varying from ca 2.4 to 5.8°, and the para nitro group is inclined to the benzene ring by a much larger angle, varying between ca 37.2 and 42.6°. Similar observations were made for the conformation of the barbiturate anion in the title molecular salt.
Epilepsy (convulsion) is one of the most common neurodegenerative disorder affecting at least 50 million people worldwide. Brain dysfunction due to different causes leads to epilepsy (Fisher et al., 2005).
have a pyrimidone ring system. From their introduction into clinical practice at the beginning of the 20th century until recent years, they have occupied a vital place in the pharmacopoeia as CNS drugs (Yadav, 2004). The anticonvulsant activity of the synthesized barbiturate has been measured by employing the Maximal Electro Shock method (Kulkarni, 1999). In the present investigation, the title molecular salt reduces the clonus phase of convulsion to a greater extent than other phases of convulsion (flexion, extension and stupor) even at low dosage (25 mg kg-1) and hence may be used in the future for controlling myoclonic epilepsy of infants. The therapeutic dose induces hypnosis in albino mice. tests have also been carried out according to OECD guidelines on albino mice (LD50 >1000 mg kg -1; falls under class 4). The animals did not show any indication of behavioural changes after testing with the title molecular salt. The high safety margin reveals its significance as a potential anticonvulsant agent.Dinitrochlorobenzene (2.02 g, 0.01 mol) was dissolved in 20 ml of absolute alcohol. To this 1.56 g (0.01mol) of 1,3-dimethylbarbituric acid was added and the temperature of the mixture was raised to 323 K. To this mixture 1.13 g (0.01 mol) of creatinine in 20 ml of absolute alcohol was added. This mixture was shaken well for 2–5 h and kept as such at 298 K for 2 d. On standing, a maroon-red-coloured solid came out from the solution. The solid was powdered well, washed with absolute alcohol and dried with ether and then recrystallized from absolute alcohol. The solution was left to stand and maroon-red block-shaped crystals were obtained after two weeks. The crystals were harvested and air dried (yield: 80%; m.p. 483 K).
Crystal data, data collection and structure
details are summarized in Table 2. The NH H atoms were located from a difference Fourier map and freely refined. The water molecule H atoms were also located from a difference Fourier map and refined with Uiso(H) = 1.5Ueq(O). The C-bound H atoms were included in calculated positions and treated as riding atoms: C—H = 0.93–0.97 Å with Uiso(H) = 1.5Ueq(C-methyl) and 1.2Ueq(C) for other H atoms.Creatinine is a breakdown product of creatine phosphate during metabolic activity in living systems (Ueda, 1964). Creatinine exists in both the amino and the imino tautomeric forms. Due to the presence of various functional groups such as CH3, CH2, NH, NH2 and C═O, it can form C—H···O, N—H···O and O—H···O hydrogen bonds with other molecules. are pyrimidine derivatives which exhibit their action by modulating the ion channel. Pyrimidine and its derivatives have been shown to be effective medications (Brown, 1962; Gauthier et al., 1963; Shorvon, 2004; Jain et al., 2006; Tripathi, 2009). In this context, a number of active molecular salts with different barbiturate entities and cationic counter parts have been described (see for example: Rajamani & Kalaivani, 2015; Gomathi & Kalaivani, 2015). Herein, we describe the synthesis and of the title molecular salt, which has been shown to exhibit anticonvulsant and hypnotic activities.
The structure of the title molecular salt is illustrated in Fig. 1. The bond lengths and bond angles are normal and comparable with those observed in related
(Sridevi & Kalaivani, 2012; Gunaseelan & Doraisamyraja, 2014). The five-membered ring of the creatininium (2-amino-1-methyl-4-oxo-4,5-dihydro-1H-imidazol-3-ium) cation is planar with an r.m.s. deviation of 0.015 Å. In the anion, 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 nitro group ortho with respect to ring junction is inclined to the benzene ring to which it is attached by 37.6 (2)°, while the nitro group para with respect to the ring junction is inclined to the benzene ring by 7.4 (3)°. The different dihedral angles imply that though two nitro groups are involved in delocalizing the negative charge on the oxygen atom of barbiturate ion, the para nitro group is more effective than the ortho nitro group.In the crystal, the anion and cation are linked via N—H···O hydrogen bonds, forming sheets parallel to the ab plane (Fig. 2 and Table 1). The sheets are linked via O—H···O hydrogen bonds involving the water molecule, forming a three-dimensional framework (Fig. 3 and Table 1). Within the framework, there are C—H···O hydrogen bonds present (Table 1).
A search of the Cambridge Structural Database (CSD, V53.7, last update February 2016; Groom & Allen, 2014) for the title anion as sub-structure gave 17 hits, of which five involve 5-(2,4-dinitrophenyl)-1,3-dimethylbarbiturate and organic cations. They include the molecular salts of 3-aminopyridinium (CSD refcode QUNRAU; Kalaivani & Sridevi, 2015a), 4-aminopyridinium (QUNROI; Kalaivani & Sridevi, 2015b), N,N-diethylethanolammonium (QUNRUO; Kalaivani & Sridevi, 2015c), trimethylammonium (CORWUD; Gunaseelan & Doraisamyraja, 2014) and 2-methylpyridinium (YAVSOF; Sridevi & Kalaivani, 2012). In the anions, the benzene ring is inclined to the mean plane of the pyrimidine ring by dihedral angles varying from ca 39.0 to 50.5°. The ortho nitro group is inclined to the benzene ring by dihedral angles varying from ca 2.4 to 5.8°, and the para nitro group is inclined to the benzene ring by a much larger angle, varying between ca 37.2 and 42.6°. Similar observations were made for the conformation of the barbiturate anion in the title molecular salt.
Epilepsy (convulsion) is one of the most common neurodegenerative disorder affecting at least 50 million people worldwide. Brain dysfunction due to different causes leads to epilepsy (Fisher et al., 2005).
have a pyrimidone ring system. From their introduction into clinical practice at the beginning of the 20th century until recent years, they have occupied a vital place in the pharmacopoeia as CNS drugs (Yadav, 2004). The anticonvulsant activity of the synthesized barbiturate has been measured by employing the Maximal Electro Shock method (Kulkarni, 1999). In the present investigation, the title molecular salt reduces the clonus phase of convulsion to a greater extent than other phases of convulsion (flexion, extension and stupor) even at low dosage (25 mg kg-1) and hence may be used in the future for controlling myoclonic epilepsy of infants. The therapeutic dose induces hypnosis in albino mice. tests have also been carried out according to OECD guidelines on albino mice (LD50 >1000 mg kg -1; falls under class 4). The animals did not show any indication of behavioural changes after testing with the title molecular salt. The high safety margin reveals its significance as a potential anticonvulsant agent.Dinitrochlorobenzene (2.02 g, 0.01 mol) was dissolved in 20 ml of absolute alcohol. To this 1.56 g (0.01mol) of 1,3-dimethylbarbituric acid was added and the temperature of the mixture was raised to 323 K. To this mixture 1.13 g (0.01 mol) of creatinine in 20 ml of absolute alcohol was added. This mixture was shaken well for 2–5 h and kept as such at 298 K for 2 d. On standing, a maroon-red-coloured solid came out from the solution. The solid was powdered well, washed with absolute alcohol and dried with ether and then recrystallized from absolute alcohol. The solution was left to stand and maroon-red block-shaped crystals were obtained after two weeks. The crystals were harvested and air dried (yield: 80%; m.p. 483 K).
detailsCrystal data, data collection and structure
details are summarized in Table 2. The NH H atoms were located from a difference Fourier map and freely refined. The water molecule H atoms were also located from a difference Fourier map and refined with Uiso(H) = 1.5Ueq(O). The C-bound H atoms were included in calculated positions and treated as riding atoms: C—H = 0.93–0.97 Å with Uiso(H) = 1.5Ueq(C-methyl) and 1.2Ueq(C) for other H atoms.Data collection: APEX2 (Bruker, 2004); cell
APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2014/7 (Sheldrick, 2015) and PLATON (Spek, 2009).Fig. 1. The molecular structure of the title molecular salt, with atom labelling. Displacement ellipsoids are drawn at the 40% probability level. | |
Fig. 2. A view along the c axis of the crystal packing of the title molecular salt. The hydrogen bonds are shown as dashed lines (see Table 1), and the water molecule and C-bound H atoms have been omitted for clarity. | |
Fig. 3. A view along the a axis of the crystal packing of the title molecular salt. The hydrogen bonds are shown as dashed lines (Table 1). The C-bound H atoms have been omitted for clarity, and the water molecules are shown as red balls. |
C4H8N3O+·C12H9N4O7−·H2O | F(000) = 944 |
Mr = 453.38 | Dx = 1.600 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 12.6926 (3) Å | Cell parameters from 7465 reflections |
b = 7.3093 (2) Å | θ = 3.0–26.5° |
c = 20.6213 (5) Å | µ = 0.13 mm−1 |
β = 100.420 (4)° | T = 293 K |
V = 1881.57 (9) Å3 | Block, brown |
Z = 4 | 0.35 × 0.30 × 0.25 mm |
Bruker Kappa APEXII CCD Diffractometer | 5338 independent reflections |
Radiation source: fine-focus sealed tube | 3586 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.037 |
ω and φ scan | θmax = 29.8°, θmin = 3.0° |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | h = −17→17 |
Tmin = 0.954, Tmax = 0.969 | k = −9→10 |
32561 measured reflections | l = −28→28 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.051 | Hydrogen site location: mixed |
wR(F2) = 0.137 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0513P)2 + 1.1255P] where P = (Fo2 + 2Fc2)/3 |
5338 reflections | (Δ/σ)max < 0.001 |
310 parameters | Δρmax = 0.40 e Å−3 |
0 restraints | Δρmin = −0.36 e Å−3 |
C4H8N3O+·C12H9N4O7−·H2O | V = 1881.57 (9) Å3 |
Mr = 453.38 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 12.6926 (3) Å | µ = 0.13 mm−1 |
b = 7.3093 (2) Å | T = 293 K |
c = 20.6213 (5) Å | 0.35 × 0.30 × 0.25 mm |
β = 100.420 (4)° |
Bruker Kappa APEXII CCD Diffractometer | 5338 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | 3586 reflections with I > 2σ(I) |
Tmin = 0.954, Tmax = 0.969 | Rint = 0.037 |
32561 measured reflections |
R[F2 > 2σ(F2)] = 0.051 | 0 restraints |
wR(F2) = 0.137 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.40 e Å−3 |
5338 reflections | Δρmin = −0.36 e Å−3 |
310 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.51360 (14) | 1.1815 (3) | 0.40647 (8) | 0.0644 (5) | |
O2 | 0.66430 (15) | 1.0674 (3) | 0.45047 (7) | 0.0649 (5) | |
O3 | 0.42214 (11) | 1.1907 (2) | 0.16944 (8) | 0.0524 (4) | |
O4 | 0.54626 (11) | 1.31323 (19) | 0.12732 (7) | 0.0418 (3) | |
O5 | 0.57211 (10) | 0.91799 (18) | 0.10996 (6) | 0.0350 (3) | |
O6 | 0.81530 (12) | 0.9893 (3) | −0.02112 (7) | 0.0586 (5) | |
O7 | 0.90227 (10) | 1.1964 (2) | 0.18675 (6) | 0.0403 (3) | |
O8 | 0.15322 (15) | 0.4142 (3) | 0.20438 (9) | 0.0682 (5) | |
N1 | 0.60178 (14) | 1.1239 (3) | 0.40331 (8) | 0.0429 (4) | |
N2 | 0.51596 (12) | 1.2223 (2) | 0.16920 (7) | 0.0326 (3) | |
N3 | 0.69565 (12) | 0.9495 (2) | 0.04581 (7) | 0.0321 (3) | |
N4 | 0.85766 (12) | 1.0943 (2) | 0.08271 (7) | 0.0345 (4) | |
N5 | 0.32746 (12) | 0.6035 (2) | 0.11207 (7) | 0.0337 (3) | |
N6 | 0.31529 (15) | 0.5560 (3) | 0.21465 (9) | 0.0421 (4) | |
H6N | 0.3318 (19) | 0.566 (3) | 0.2560 (13) | 0.054 (7)* | |
N7 | 0.46476 (15) | 0.7122 (3) | 0.19231 (9) | 0.0423 (4) | |
H7N1 | 0.4961 (19) | 0.765 (3) | 0.1642 (13) | 0.053 (7)* | |
H7N2 | 0.495 (2) | 0.715 (4) | 0.2309 (14) | 0.062 (8)* | |
C1 | 0.63499 (15) | 1.1227 (3) | 0.33968 (8) | 0.0314 (4) | |
C2 | 0.56212 (14) | 1.1645 (3) | 0.28472 (9) | 0.0312 (4) | |
H2 | 0.4924 | 1.1977 | 0.2876 | 0.037* | |
C3 | 0.59481 (13) | 1.1560 (2) | 0.22486 (8) | 0.0267 (3) | |
C4 | 0.69704 (13) | 1.1026 (2) | 0.21720 (8) | 0.0248 (3) | |
C5 | 0.76756 (14) | 1.0670 (2) | 0.27580 (8) | 0.0292 (4) | |
H5 | 0.8379 | 1.0361 | 0.2737 | 0.035* | |
C6 | 0.73800 (15) | 1.0754 (3) | 0.33611 (9) | 0.0319 (4) | |
H6 | 0.7871 | 1.0494 | 0.3742 | 0.038* | |
C7 | 0.72996 (13) | 1.0733 (2) | 0.15415 (8) | 0.0254 (3) | |
C8 | 0.66101 (13) | 0.9796 (2) | 0.10494 (8) | 0.0265 (3) | |
C9 | 0.79069 (15) | 1.0101 (3) | 0.03282 (9) | 0.0364 (4) | |
C10 | 0.83323 (13) | 1.1237 (2) | 0.14538 (8) | 0.0289 (4) | |
C11 | 0.96085 (17) | 1.1545 (4) | 0.06976 (11) | 0.0524 (6) | |
H11A | 0.9979 | 1.2210 | 0.1072 | 0.079* | |
H11B | 0.9503 | 1.2323 | 0.0316 | 0.079* | |
H11C | 1.0026 | 1.0499 | 0.0619 | 0.079* | |
C12 | 0.62720 (17) | 0.8444 (3) | −0.00485 (10) | 0.0446 (5) | |
H12A | 0.6045 | 0.7346 | 0.0142 | 0.067* | |
H12B | 0.6662 | 0.8131 | −0.0390 | 0.067* | |
H12C | 0.5656 | 0.9161 | −0.0232 | 0.067* | |
C13 | 0.22262 (18) | 0.4829 (3) | 0.18063 (11) | 0.0444 (5) | |
C14 | 0.22732 (16) | 0.5085 (3) | 0.10967 (10) | 0.0429 (5) | |
H14A | 0.2274 | 0.3919 | 0.0872 | 0.051* | |
H14B | 0.1675 | 0.5814 | 0.0877 | 0.051* | |
C15 | 0.37450 (15) | 0.6299 (3) | 0.17320 (9) | 0.0334 (4) | |
C16 | 0.37034 (17) | 0.6532 (3) | 0.05467 (9) | 0.0404 (5) | |
H16A | 0.3160 | 0.6388 | 0.0161 | 0.061* | |
H16B | 0.4301 | 0.5757 | 0.0513 | 0.061* | |
H16C | 0.3935 | 0.7784 | 0.0583 | 0.061* | |
O1W | 0.21039 (19) | 0.9763 (4) | 0.15794 (9) | 0.0809 (7) | |
H1WA | 0.192 (3) | 0.992 (6) | 0.118 (2) | 0.121* | |
H1WB | 0.273 (3) | 0.976 (6) | 0.171 (2) | 0.121* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0526 (10) | 0.1010 (14) | 0.0450 (9) | 0.0003 (10) | 0.0227 (8) | −0.0113 (9) |
O2 | 0.0679 (11) | 0.1012 (15) | 0.0246 (7) | −0.0079 (10) | 0.0059 (7) | 0.0078 (8) |
O3 | 0.0254 (7) | 0.0828 (12) | 0.0468 (9) | 0.0056 (7) | 0.0006 (6) | −0.0017 (8) |
O4 | 0.0438 (8) | 0.0430 (8) | 0.0357 (7) | 0.0047 (6) | −0.0008 (6) | 0.0076 (6) |
O5 | 0.0309 (7) | 0.0410 (7) | 0.0322 (7) | −0.0071 (5) | 0.0032 (5) | −0.0064 (6) |
O6 | 0.0440 (8) | 0.1058 (14) | 0.0280 (7) | 0.0054 (9) | 0.0118 (6) | −0.0102 (8) |
O7 | 0.0288 (6) | 0.0586 (9) | 0.0318 (7) | −0.0090 (6) | 0.0007 (5) | −0.0060 (6) |
O8 | 0.0617 (11) | 0.0856 (13) | 0.0648 (11) | −0.0101 (10) | 0.0316 (9) | 0.0136 (10) |
N1 | 0.0469 (10) | 0.0557 (11) | 0.0278 (8) | −0.0132 (8) | 0.0108 (7) | −0.0056 (8) |
N2 | 0.0297 (8) | 0.0379 (9) | 0.0285 (8) | 0.0062 (6) | 0.0003 (6) | −0.0053 (6) |
N3 | 0.0295 (7) | 0.0421 (9) | 0.0231 (7) | 0.0029 (6) | 0.0009 (6) | −0.0081 (6) |
N4 | 0.0249 (7) | 0.0524 (10) | 0.0271 (7) | 0.0021 (7) | 0.0068 (6) | −0.0017 (7) |
N5 | 0.0316 (8) | 0.0446 (9) | 0.0253 (7) | −0.0003 (7) | 0.0059 (6) | −0.0001 (6) |
N6 | 0.0536 (11) | 0.0490 (10) | 0.0251 (8) | 0.0033 (8) | 0.0109 (7) | 0.0023 (7) |
N7 | 0.0430 (10) | 0.0549 (11) | 0.0266 (9) | −0.0013 (8) | 0.0001 (7) | −0.0003 (8) |
C1 | 0.0373 (9) | 0.0351 (10) | 0.0222 (8) | −0.0065 (8) | 0.0067 (7) | −0.0042 (7) |
C2 | 0.0280 (8) | 0.0358 (9) | 0.0304 (9) | −0.0004 (7) | 0.0070 (7) | −0.0045 (7) |
C3 | 0.0252 (8) | 0.0297 (9) | 0.0237 (8) | 0.0006 (7) | 0.0000 (6) | −0.0031 (6) |
C4 | 0.0258 (8) | 0.0236 (8) | 0.0238 (8) | −0.0015 (6) | 0.0014 (6) | −0.0021 (6) |
C5 | 0.0261 (8) | 0.0329 (9) | 0.0275 (8) | 0.0007 (7) | 0.0019 (6) | 0.0007 (7) |
C6 | 0.0330 (9) | 0.0361 (10) | 0.0238 (8) | −0.0028 (7) | −0.0022 (7) | 0.0006 (7) |
C7 | 0.0243 (8) | 0.0291 (8) | 0.0220 (8) | 0.0017 (6) | 0.0017 (6) | −0.0017 (6) |
C8 | 0.0267 (8) | 0.0283 (9) | 0.0236 (8) | 0.0035 (7) | 0.0022 (6) | −0.0012 (6) |
C9 | 0.0314 (9) | 0.0527 (12) | 0.0248 (8) | 0.0095 (8) | 0.0042 (7) | −0.0017 (8) |
C10 | 0.0264 (8) | 0.0337 (9) | 0.0256 (8) | 0.0042 (7) | 0.0021 (6) | 0.0003 (7) |
C11 | 0.0337 (10) | 0.0796 (17) | 0.0469 (12) | −0.0037 (11) | 0.0153 (9) | −0.0028 (12) |
C12 | 0.0435 (11) | 0.0550 (13) | 0.0320 (10) | 0.0030 (10) | −0.0024 (8) | −0.0169 (9) |
C13 | 0.0464 (12) | 0.0476 (12) | 0.0426 (11) | 0.0034 (10) | 0.0170 (9) | 0.0039 (9) |
C14 | 0.0368 (10) | 0.0555 (13) | 0.0372 (10) | −0.0052 (9) | 0.0090 (8) | −0.0014 (9) |
C15 | 0.0386 (10) | 0.0349 (10) | 0.0266 (9) | 0.0081 (8) | 0.0053 (7) | −0.0001 (7) |
C16 | 0.0459 (11) | 0.0476 (12) | 0.0271 (9) | −0.0070 (9) | 0.0051 (8) | 0.0031 (8) |
O1W | 0.0862 (15) | 0.1218 (18) | 0.0345 (9) | 0.0251 (15) | 0.0102 (10) | −0.0039 (11) |
O1—N1 | 1.208 (2) | C1—C6 | 1.367 (3) |
O2—N1 | 1.211 (2) | C2—C3 | 1.373 (2) |
O3—N2 | 1.214 (2) | C2—H2 | 0.9300 |
O4—N2 | 1.207 (2) | C3—C4 | 1.391 (2) |
O5—C8 | 1.237 (2) | C4—C5 | 1.392 (2) |
O6—C9 | 1.218 (2) | C4—C7 | 1.452 (2) |
O7—C10 | 1.228 (2) | C5—C6 | 1.364 (2) |
O8—C13 | 1.193 (3) | C5—H5 | 0.9300 |
N1—C1 | 1.449 (2) | C6—H6 | 0.9300 |
N2—C3 | 1.462 (2) | C7—C8 | 1.394 (2) |
N3—C9 | 1.356 (2) | C7—C10 | 1.404 (2) |
N3—C8 | 1.387 (2) | C11—H11A | 0.9600 |
N3—C12 | 1.452 (2) | C11—H11B | 0.9600 |
N4—C9 | 1.358 (2) | C11—H11C | 0.9600 |
N4—C10 | 1.399 (2) | C12—H12A | 0.9600 |
N4—C11 | 1.452 (2) | C12—H12B | 0.9600 |
N5—C15 | 1.308 (2) | C12—H12C | 0.9600 |
N5—C16 | 1.436 (2) | C13—C14 | 1.487 (3) |
N5—C14 | 1.441 (2) | C14—H14A | 0.9700 |
N6—C15 | 1.349 (3) | C14—H14B | 0.9700 |
N6—C13 | 1.365 (3) | C16—H16A | 0.9600 |
N6—H6N | 0.84 (3) | C16—H16B | 0.9600 |
N7—C15 | 1.291 (3) | C16—H16C | 0.9600 |
N7—H7N1 | 0.85 (3) | O1W—H1WA | 0.81 (4) |
N7—H7N2 | 0.82 (3) | O1W—H1WB | 0.79 (4) |
C1—C2 | 1.362 (2) | ||
O1—N1—O2 | 123.65 (18) | C10—C7—C4 | 120.21 (15) |
O1—N1—C1 | 118.37 (17) | O5—C8—N3 | 117.07 (15) |
O2—N1—C1 | 117.98 (18) | O5—C8—C7 | 125.47 (15) |
O4—N2—O3 | 123.20 (16) | N3—C8—C7 | 117.45 (15) |
O4—N2—C3 | 118.87 (15) | O6—C9—N3 | 121.57 (18) |
O3—N2—C3 | 117.82 (16) | O6—C9—N4 | 121.32 (18) |
C9—N3—C8 | 123.82 (15) | N3—C9—N4 | 117.11 (15) |
C9—N3—C12 | 117.94 (15) | O7—C10—N4 | 117.31 (16) |
C8—N3—C12 | 118.23 (15) | O7—C10—C7 | 126.12 (16) |
C9—N4—C10 | 123.82 (15) | N4—C10—C7 | 116.53 (15) |
C9—N4—C11 | 117.39 (16) | N4—C11—H11A | 109.5 |
C10—N4—C11 | 118.79 (16) | N4—C11—H11B | 109.5 |
C15—N5—C16 | 125.59 (17) | H11A—C11—H11B | 109.5 |
C15—N5—C14 | 110.50 (15) | N4—C11—H11C | 109.5 |
C16—N5—C14 | 123.85 (16) | H11A—C11—H11C | 109.5 |
C15—N6—C13 | 111.00 (17) | H11B—C11—H11C | 109.5 |
C15—N6—H6N | 122.8 (17) | N3—C12—H12A | 109.5 |
C13—N6—H6N | 125.9 (17) | N3—C12—H12B | 109.5 |
C15—N7—H7N1 | 120.1 (17) | H12A—C12—H12B | 109.5 |
C15—N7—H7N2 | 122.5 (19) | N3—C12—H12C | 109.5 |
H7N1—N7—H7N2 | 117 (2) | H12A—C12—H12C | 109.5 |
C2—C1—C6 | 121.62 (16) | H12B—C12—H12C | 109.5 |
C2—C1—N1 | 119.16 (17) | O8—C13—N6 | 125.8 (2) |
C6—C1—N1 | 119.21 (16) | O8—C13—C14 | 128.4 (2) |
C1—C2—C3 | 117.90 (16) | N6—C13—C14 | 105.78 (17) |
C1—C2—H2 | 121.0 | N5—C14—C13 | 102.66 (16) |
C3—C2—H2 | 121.0 | N5—C14—H14A | 111.2 |
C2—C3—C4 | 123.67 (16) | C13—C14—H14A | 111.2 |
C2—C3—N2 | 114.55 (15) | N5—C14—H14B | 111.2 |
C4—C3—N2 | 121.60 (15) | C13—C14—H14B | 111.2 |
C3—C4—C5 | 114.87 (15) | H14A—C14—H14B | 109.1 |
C3—C4—C7 | 124.65 (15) | N7—C15—N5 | 126.03 (18) |
C5—C4—C7 | 120.38 (15) | N7—C15—N6 | 123.96 (18) |
C6—C5—C4 | 122.91 (16) | N5—C15—N6 | 110.00 (18) |
C6—C5—H5 | 118.5 | N5—C16—H16A | 109.5 |
C4—C5—H5 | 118.5 | N5—C16—H16B | 109.5 |
C5—C6—C1 | 118.95 (16) | H16A—C16—H16B | 109.5 |
C5—C6—H6 | 120.5 | N5—C16—H16C | 109.5 |
C1—C6—H6 | 120.5 | H16A—C16—H16C | 109.5 |
C8—C7—C10 | 120.84 (15) | H16B—C16—H16C | 109.5 |
C8—C7—C4 | 118.68 (15) | H1WA—O1W—H1WB | 115 (4) |
O1—N1—C1—C2 | −8.0 (3) | C10—C7—C8—N3 | −4.2 (2) |
O2—N1—C1—C2 | 172.15 (19) | C4—C7—C8—N3 | −178.39 (15) |
O1—N1—C1—C6 | 173.55 (19) | C8—N3—C9—O6 | −175.85 (19) |
O2—N1—C1—C6 | −6.3 (3) | C12—N3—C9—O6 | 5.2 (3) |
C6—C1—C2—C3 | 0.7 (3) | C8—N3—C9—N4 | 4.5 (3) |
N1—C1—C2—C3 | −177.76 (16) | C12—N3—C9—N4 | −174.44 (17) |
C1—C2—C3—C4 | 1.8 (3) | C10—N4—C9—O6 | 179.29 (19) |
C1—C2—C3—N2 | −173.48 (16) | C11—N4—C9—O6 | −1.5 (3) |
O4—N2—C3—C2 | 139.47 (17) | C10—N4—C9—N3 | −1.0 (3) |
O3—N2—C3—C2 | −36.7 (2) | C11—N4—C9—N3 | 178.17 (19) |
O4—N2—C3—C4 | −35.9 (2) | C9—N4—C10—O7 | 177.77 (18) |
O3—N2—C3—C4 | 147.96 (17) | C11—N4—C10—O7 | −1.4 (3) |
C2—C3—C4—C5 | −3.4 (3) | C9—N4—C10—C7 | −4.6 (3) |
N2—C3—C4—C5 | 171.52 (15) | C11—N4—C10—C7 | 176.16 (18) |
C2—C3—C4—C7 | 172.93 (17) | C8—C7—C10—O7 | −175.41 (17) |
N2—C3—C4—C7 | −12.2 (3) | C4—C7—C10—O7 | −1.3 (3) |
C3—C4—C5—C6 | 2.8 (3) | C8—C7—C10—N4 | 7.2 (2) |
C7—C4—C5—C6 | −173.66 (17) | C4—C7—C10—N4 | −178.70 (15) |
C4—C5—C6—C1 | −0.7 (3) | C15—N6—C13—O8 | −177.2 (2) |
C2—C1—C6—C5 | −1.2 (3) | C15—N6—C13—C14 | 2.4 (2) |
N1—C1—C6—C5 | 177.25 (17) | C15—N5—C14—C13 | 0.1 (2) |
C3—C4—C7—C8 | −43.0 (2) | C16—N5—C14—C13 | 177.41 (18) |
C5—C4—C7—C8 | 133.16 (17) | O8—C13—C14—N5 | 178.1 (2) |
C3—C4—C7—C10 | 142.84 (18) | N6—C13—C14—N5 | −1.5 (2) |
C5—C4—C7—C10 | −41.0 (2) | C16—N5—C15—N7 | 3.3 (3) |
C9—N3—C8—O5 | 179.40 (17) | C14—N5—C15—N7 | −179.4 (2) |
C12—N3—C8—O5 | −1.7 (2) | C16—N5—C15—N6 | −175.89 (18) |
C9—N3—C8—C7 | −1.9 (3) | C14—N5—C15—N6 | 1.4 (2) |
C12—N3—C8—C7 | 177.04 (16) | C13—N6—C15—N7 | 178.3 (2) |
C10—C7—C8—O5 | 174.36 (17) | C13—N6—C15—N5 | −2.4 (2) |
C4—C7—C8—O5 | 0.2 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N7—H7N1···O5 | 0.85 (3) | 1.96 (3) | 2.800 (2) | 171 (2) |
N7—H7N2···O7i | 0.82 (3) | 1.95 (3) | 2.749 (2) | 165 (3) |
N6—H6N···O1Wii | 0.84 (3) | 2.05 (3) | 2.767 (2) | 142 (2) |
O1W—H1WA···O6iii | 0.81 (4) | 1.99 (4) | 2.792 (2) | 166 (4) |
O1W—H1WB···O3 | 0.79 (4) | 2.47 (4) | 3.083 (3) | 136 (4) |
O1W—H1WB···O8iv | 0.79 (4) | 2.61 (4) | 3.080 (3) | 120 (4) |
C12—H12C···O5iii | 0.96 | 2.57 | 3.483 (3) | 159 |
C14—H14B···O1ii | 0.97 | 2.44 | 3.270 (3) | 144 |
C16—H16C···O5 | 0.96 | 2.54 | 3.248 (2) | 131 |
Symmetry codes: (i) −x+3/2, y−1/2, −z+1/2; (ii) −x+1/2, y−1/2, −z+1/2; (iii) −x+1, −y+2, −z; (iv) −x+1/2, y+1/2, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N7—H7N1···O5 | 0.85 (3) | 1.96 (3) | 2.800 (2) | 171 (2) |
N7—H7N2···O7i | 0.82 (3) | 1.95 (3) | 2.749 (2) | 165 (3) |
N6—H6N···O1Wii | 0.84 (3) | 2.05 (3) | 2.767 (2) | 142 (2) |
O1W—H1WA···O6iii | 0.81 (4) | 1.99 (4) | 2.792 (2) | 166 (4) |
O1W—H1WB···O3 | 0.79 (4) | 2.47 (4) | 3.083 (3) | 136 (4) |
O1W—H1WB···O8iv | 0.79 (4) | 2.61 (4) | 3.080 (3) | 120 (4) |
C12—H12C···O5iii | 0.96 | 2.57 | 3.483 (3) | 159 |
C14—H14B···O1ii | 0.97 | 2.44 | 3.270 (3) | 144 |
C16—H16C···O5 | 0.96 | 2.54 | 3.248 (2) | 131 |
Symmetry codes: (i) −x+3/2, y−1/2, −z+1/2; (ii) −x+1/2, y−1/2, −z+1/2; (iii) −x+1, −y+2, −z; (iv) −x+1/2, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C4H8N3O+·C12H9N4O7−·H2O |
Mr | 453.38 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 293 |
a, b, c (Å) | 12.6926 (3), 7.3093 (2), 20.6213 (5) |
β (°) | 100.420 (4) |
V (Å3) | 1881.57 (9) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.13 |
Crystal size (mm) | 0.35 × 0.30 × 0.25 |
Data collection | |
Diffractometer | Bruker Kappa APEXII CCD Diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2004) |
Tmin, Tmax | 0.954, 0.969 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 32561, 5338, 3586 |
Rint | 0.037 |
(sin θ/λ)max (Å−1) | 0.699 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.051, 0.137, 1.03 |
No. of reflections | 5338 |
No. of parameters | 310 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.40, −0.36 |
Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SIR92 (Altomare et al., 1993), ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008), SHELXL2014/7 (Sheldrick, 2015) and PLATON (Spek, 2009).
Acknowledgements
The authors gratefully acknowledge the DST, New Delhi for financial assistance, the SAIF-IIT Madras, Chennai − 36 for the single-crystal XRD data collection, and the KMCH College of Pharmacy, Coimbatore, for anticonvulsant activity results.
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