research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 72| Part 5| May 2016| Pages 620-623
doi:10.1107/S2056989016005247

Crystal structure of creatininium 5-(2,4-di­nitro­phen­yl)-1,3-di­methyl­barbiturate monohydrate: a potential anti­convulsant agent

CROSSMARK_Color_square_no_text.svg
Ponnusamy Poornima Devia and Doraisamyraja Kalaivania*

aPG and Research Department of Chemistry, Seethalakshmi Ramaswami College, Tiruchirappalli 620 002, Tamil Nadu, India
*Correspondence e-mail: kalaivbalaj@yahoo.co.in

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 26 March 2016; accepted 28 March 2016; online 5 April 2016)

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.

CCDC reference: 1060400

1. Chemical context

Creatinine is a breakdown product of creatine phosphate during metabolic activity in living systems (Ueda, 1964[Ueda, H. (1964). J. Chem. Phys. 40, 901-905.]). 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. Barbiturates 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[Brown, D. J. (1962). The Chemistry of Heterocyclic Compounds, edited by. A. Weissberger, p. 16. New York: Interscience.]; Gauthier et al., 1963[Gauthier, B. I., Tixier, R. & Uzan, A. (1963). Ann. Pharm. Fr. 21, 655-666.]; Shorvon, 2004[Shorvon, S. D. (2004). The Treatment of Epilepsy. Oxford, UK: Blackwell Publishers.]; Jain et al., 2006[Jain, K. S., Chitre, T. S., Miniyar, P. B., Kathiravan, M. K., Bendre, V. S., Veer, V. S., Shahane, S. R. & Shishoo, C. J. (2006). Curr. Sci. 90, 793-803.]; Tripathi, 2009[Tripathi, K. D. (2009). Essentials of Medical Pharmacology, 6th ed., Chennai: Jaypee Brothers Medical Publishers.]). 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[Rajamani, K. & Kalaivani, D. (2015). Chem. Cent. J. 9, 1-12.]; Gomathi & Kalaivani, 2015[Gomathi, J. & Kalaivani, D. (2015). Acta Cryst. E71, 723-725.]). Herein, we describe the synthesis and crystal structure of the title mol­ecular salt, which has been shown to exhibit anti­convulsant and hypnotic activities.

[Scheme 1]

2. Structural commentary

The structure of the title mol­ecular salt is illustrated in Fig. 1[link]. The bond lengths and bond angles are normal and comparable with those observed in related barbiturates (Sridevi & Kalaivani, 2012[Sridevi, G. & Kalaivani, D. (2012). Acta Cryst. E68, o1044.]; Gunaseelan & Doraisamyraja, 2014[Gunaseelan, S. & Doraisamyraja, K. (2014). Acta Cryst. E70, o1102-o1103.]). 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.

[Figure 1]
Figure 1
The mol­ecular structure of the title mol­ecular salt, with atom labelling. Displacement ellipsoids are drawn at the 40% probability level.

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[link] and Table 1[link]). The sheets are linked via O—H⋯O hydrogen bonds involving the water mol­ecule, forming a three-dimensional framework (Fig. 3[link] and Table 1[link]). Within the framework, there are C—H⋯O hydrogen bonds present (Table 1[link]).

Table 1
Hydrogen-bond geometry (Å, °)

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+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) -x+1, -y+2, -z; (iv) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].
[Figure 2]
Figure 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[link]), and the water mol­ecule and C-bound H atoms have been omitted for clarity.
[Figure 3]
Figure 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[link]). The C-bound H atoms have been omitted for clarity, and the water mol­ecules are shown as red balls.

4. Database survey

A search of the Cambridge Structural Database (CSD, Version 53.7, last update February 2016; Groom & Allen, 2014[Groom, C. R. & Allen, F. H. (2014). Angew. Chem. Int. Ed. 53, 662-671.]) 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[Kalaivani, D. & Sridevi, G. (2015a). Private communication (refcode QUNRAU). CCDC, Cambridge, England.]), 4-amino­pyridinium (QUNROI; Kalaivani & Sridevi, 2015b[Kalaivani, D. & Sridevi, G. (2015b). Private communication (refcode QUNROI). CCDC, Cambridge, England.]), N,N-di­ethyl­ethano­lammonium (QUNRUO; Kalaivani & Sridevi, 2015c[Kalaivani, D. & Sridevi, G. (2015c). Private communication (refcode QUNRUO). CCDC, Cambridge, England.]), tri­methyl­ammonium (CORWUD; Gunaseelan & Doraisamyraja, 2014[Gunaseelan, S. & Doraisamyraja, K. (2014). Acta Cryst. E70, o1102-o1103.]) and 2-methyl­pyridinium (YAVSOF; Sridevi & Kalaivani, 2012[Sridevi, G. & Kalaivani, D. (2012). Acta Cryst. E68, o1044.]). 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[Fisher, R. S., van Emde Boas, W., Blume, W., Elger, C., Genton, P., Lee, P. & Engel, J. Jr (2005). Epilepsia, 46, 470-472.]). Barbiturates 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[Yadav, A. V. (2004). Pharmacology and Toxicology, 11th ed, pp. 57-67. Mumbai: Nirali Prakas.]). The anti­convulsant activity of the synthesized barbiturate has been measured by employing the Maximal Electro Shock method (Kulkarni, 1999[Kulkarni, S. K. (1999). Handbook of Experimental Pharamacology Vallabh Prakashan, Mumbai, p. 131.]). 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. Acute toxicity 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 refinement details are summarized in Table 2[link]. 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.

Table 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[Bruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
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 SAINT and XPREP (Bruker, 2004[Bruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SIR92 (Altomare et al., 1993[Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343-350.]), ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]), Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]), SHELXL2014/7 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

CCDC reference: 1060400

Crystal structure: contains datablocks global, I. DOI: 10.1107/S2056989016005247/su5291sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989016005247/su5291Isup2.hkl

checkCIF report


Chemical context top

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. Barbiturates 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 crystal structure of the title molecular salt, which has been shown to exhibit anti­convulsant and hypnotic activities.

Structural commentary top

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 barbiturates (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.

Supra­molecular features top

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).

Database survey top

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.

Biological activity top

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). Barbiturates 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. Acute toxicity 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.

Synthesis and crystallization top

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).

Refinement top

Crystal data, data collection and structure refinement 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.

Structure description top

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. Barbiturates 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 crystal structure 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 barbiturates (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). Barbiturates 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. Acute toxicity 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.

Synthesis and crystallization top

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).

Refinement details top

Crystal data, data collection and structure refinement 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.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: 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).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecular salt, with atom labelling. Displacement ellipsoids are drawn at the 40% probability level.
[Figure 2] 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.
[Figure 3] 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.
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 top
Crystal data top
C4H8N3O+·C12H9N4O7−·H2OF(000) = 944
Mr = 453.38Dx = 1.600 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 12.6926 (3) ÅCell parameters from 7465 reflections
b = 7.3093 (2) Åθ = 3.0–26.5°
c = 20.6213 (5) ŵ = 0.13 mm−1
β = 100.420 (4)°T = 293 K
V = 1881.57 (9) Å3Block, brown
Z = 40.35 × 0.30 × 0.25 mm
Data collection top
Bruker Kappa APEXII CCD Diffractometer5338 independent reflections
Radiation source: fine-focus sealed tube3586 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
ω and φ scanθmax = 29.8°, θmin = 3.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)		h = −17→17
Tmin = 0.954, Tmax = 0.969k = −9→10
32561 measured reflectionsl = −28→28
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.051Hydrogen site location: mixed
wR(F2) = 0.137H 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 parametersΔρmax = 0.40 e Å−3
0 restraintsΔρmin = −0.36 e Å−3
Crystal data top
C4H8N3O+·C12H9N4O7−·H2OV = 1881.57 (9) Å3
Mr = 453.38Z = 4
Monoclinic, P21/nMo Kα radiation
a = 12.6926 (3) ŵ = 0.13 mm−1
b = 7.3093 (2) ÅT = 293 K
c = 20.6213 (5) Å0.35 × 0.30 × 0.25 mm
β = 100.420 (4)°
Data collection top
Bruker Kappa APEXII CCD Diffractometer5338 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)		3586 reflections with I > 2σ(I)
Tmin = 0.954, Tmax = 0.969Rint = 0.037
32561 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0510 restraints
wR(F2) = 0.137H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.40 e Å−3
5338 reflectionsΔρmin = −0.36 e Å−3
310 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.51360 (14)1.1815 (3)0.40647 (8)0.0644 (5)
O20.66430 (15)1.0674 (3)0.45047 (7)0.0649 (5)
O30.42214 (11)1.1907 (2)0.16944 (8)0.0524 (4)
O40.54626 (11)1.31323 (19)0.12732 (7)0.0418 (3)
O50.57211 (10)0.91799 (18)0.10996 (6)0.0350 (3)
O60.81530 (12)0.9893 (3)−0.02112 (7)0.0586 (5)
O70.90227 (10)1.1964 (2)0.18675 (6)0.0403 (3)
O80.15322 (15)0.4142 (3)0.20438 (9)0.0682 (5)
N10.60178 (14)1.1239 (3)0.40331 (8)0.0429 (4)
N20.51596 (12)1.2223 (2)0.16920 (7)0.0326 (3)
N30.69565 (12)0.9495 (2)0.04581 (7)0.0321 (3)
N40.85766 (12)1.0943 (2)0.08271 (7)0.0345 (4)
N50.32746 (12)0.6035 (2)0.11207 (7)0.0337 (3)
N60.31529 (15)0.5560 (3)0.21465 (9)0.0421 (4)
H6N0.3318 (19)0.566 (3)0.2560 (13)0.054 (7)*
N70.46476 (15)0.7122 (3)0.19231 (9)0.0423 (4)
H7N10.4961 (19)0.765 (3)0.1642 (13)0.053 (7)*
H7N20.495 (2)0.715 (4)0.2309 (14)0.062 (8)*
C10.63499 (15)1.1227 (3)0.33968 (8)0.0314 (4)
C20.56212 (14)1.1645 (3)0.28472 (9)0.0312 (4)
H20.49241.19770.28760.037*
C30.59481 (13)1.1560 (2)0.22486 (8)0.0267 (3)
C40.69704 (13)1.1026 (2)0.21720 (8)0.0248 (3)
C50.76756 (14)1.0670 (2)0.27580 (8)0.0292 (4)
H50.83791.03610.27370.035*
C60.73800 (15)1.0754 (3)0.33611 (9)0.0319 (4)
H60.78711.04940.37420.038*
C70.72996 (13)1.0733 (2)0.15415 (8)0.0254 (3)
C80.66101 (13)0.9796 (2)0.10494 (8)0.0265 (3)
C90.79069 (15)1.0101 (3)0.03282 (9)0.0364 (4)
C100.83323 (13)1.1237 (2)0.14538 (8)0.0289 (4)
C110.96085 (17)1.1545 (4)0.06976 (11)0.0524 (6)
H11A0.99791.22100.10720.079*
H11B0.95031.23230.03160.079*
H11C1.00261.04990.06190.079*
C120.62720 (17)0.8444 (3)−0.00485 (10)0.0446 (5)
H12A0.60450.73460.01420.067*
H12B0.66620.8131−0.03900.067*
H12C0.56560.9161−0.02320.067*
C130.22262 (18)0.4829 (3)0.18063 (11)0.0444 (5)
C140.22732 (16)0.5085 (3)0.10967 (10)0.0429 (5)
H14A0.22740.39190.08720.051*
H14B0.16750.58140.08770.051*
C150.37450 (15)0.6299 (3)0.17320 (9)0.0334 (4)
C160.37034 (17)0.6532 (3)0.05467 (9)0.0404 (5)
H16A0.31600.63880.01610.061*
H16B0.43010.57570.05130.061*
H16C0.39350.77840.05830.061*
O1W0.21039 (19)0.9763 (4)0.15794 (9)0.0809 (7)
H1WA0.192 (3)0.992 (6)0.118 (2)0.121*
H1WB0.273 (3)0.976 (6)0.171 (2)0.121*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0526 (10)0.1010 (14)0.0450 (9)0.0003 (10)0.0227 (8)−0.0113 (9)
O20.0679 (11)0.1012 (15)0.0246 (7)−0.0079 (10)0.0059 (7)0.0078 (8)
O30.0254 (7)0.0828 (12)0.0468 (9)0.0056 (7)0.0006 (6)−0.0017 (8)
O40.0438 (8)0.0430 (8)0.0357 (7)0.0047 (6)−0.0008 (6)0.0076 (6)
O50.0309 (7)0.0410 (7)0.0322 (7)−0.0071 (5)0.0032 (5)−0.0064 (6)
O60.0440 (8)0.1058 (14)0.0280 (7)0.0054 (9)0.0118 (6)−0.0102 (8)
O70.0288 (6)0.0586 (9)0.0318 (7)−0.0090 (6)0.0007 (5)−0.0060 (6)
O80.0617 (11)0.0856 (13)0.0648 (11)−0.0101 (10)0.0316 (9)0.0136 (10)
N10.0469 (10)0.0557 (11)0.0278 (8)−0.0132 (8)0.0108 (7)−0.0056 (8)
N20.0297 (8)0.0379 (9)0.0285 (8)0.0062 (6)0.0003 (6)−0.0053 (6)
N30.0295 (7)0.0421 (9)0.0231 (7)0.0029 (6)0.0009 (6)−0.0081 (6)
N40.0249 (7)0.0524 (10)0.0271 (7)0.0021 (7)0.0068 (6)−0.0017 (7)
N50.0316 (8)0.0446 (9)0.0253 (7)−0.0003 (7)0.0059 (6)−0.0001 (6)
N60.0536 (11)0.0490 (10)0.0251 (8)0.0033 (8)0.0109 (7)0.0023 (7)
N70.0430 (10)0.0549 (11)0.0266 (9)−0.0013 (8)0.0001 (7)−0.0003 (8)
C10.0373 (9)0.0351 (10)0.0222 (8)−0.0065 (8)0.0067 (7)−0.0042 (7)
C20.0280 (8)0.0358 (9)0.0304 (9)−0.0004 (7)0.0070 (7)−0.0045 (7)
C30.0252 (8)0.0297 (9)0.0237 (8)0.0006 (7)0.0000 (6)−0.0031 (6)
C40.0258 (8)0.0236 (8)0.0238 (8)−0.0015 (6)0.0014 (6)−0.0021 (6)
C50.0261 (8)0.0329 (9)0.0275 (8)0.0007 (7)0.0019 (6)0.0007 (7)
C60.0330 (9)0.0361 (10)0.0238 (8)−0.0028 (7)−0.0022 (7)0.0006 (7)
C70.0243 (8)0.0291 (8)0.0220 (8)0.0017 (6)0.0017 (6)−0.0017 (6)
C80.0267 (8)0.0283 (9)0.0236 (8)0.0035 (7)0.0022 (6)−0.0012 (6)
C90.0314 (9)0.0527 (12)0.0248 (8)0.0095 (8)0.0042 (7)−0.0017 (8)
C100.0264 (8)0.0337 (9)0.0256 (8)0.0042 (7)0.0021 (6)0.0003 (7)
C110.0337 (10)0.0796 (17)0.0469 (12)−0.0037 (11)0.0153 (9)−0.0028 (12)
C120.0435 (11)0.0550 (13)0.0320 (10)0.0030 (10)−0.0024 (8)−0.0169 (9)
C130.0464 (12)0.0476 (12)0.0426 (11)0.0034 (10)0.0170 (9)0.0039 (9)
C140.0368 (10)0.0555 (13)0.0372 (10)−0.0052 (9)0.0090 (8)−0.0014 (9)
C150.0386 (10)0.0349 (10)0.0266 (9)0.0081 (8)0.0053 (7)−0.0001 (7)
C160.0459 (11)0.0476 (12)0.0271 (9)−0.0070 (9)0.0051 (8)0.0031 (8)
O1W0.0862 (15)0.1218 (18)0.0345 (9)0.0251 (15)0.0102 (10)−0.0039 (11)
Geometric parameters (Å, º) top
O1—N11.208 (2)C1—C61.367 (3)
O2—N11.211 (2)C2—C31.373 (2)
O3—N21.214 (2)C2—H20.9300
O4—N21.207 (2)C3—C41.391 (2)
O5—C81.237 (2)C4—C51.392 (2)
O6—C91.218 (2)C4—C71.452 (2)
O7—C101.228 (2)C5—C61.364 (2)
O8—C131.193 (3)C5—H50.9300
N1—C11.449 (2)C6—H60.9300
N2—C31.462 (2)C7—C81.394 (2)
N3—C91.356 (2)C7—C101.404 (2)
N3—C81.387 (2)C11—H11A0.9600
N3—C121.452 (2)C11—H11B0.9600
N4—C91.358 (2)C11—H11C0.9600
N4—C101.399 (2)C12—H12A0.9600
N4—C111.452 (2)C12—H12B0.9600
N5—C151.308 (2)C12—H12C0.9600
N5—C161.436 (2)C13—C141.487 (3)
N5—C141.441 (2)C14—H14A0.9700
N6—C151.349 (3)C14—H14B0.9700
N6—C131.365 (3)C16—H16A0.9600
N6—H6N0.84 (3)C16—H16B0.9600
N7—C151.291 (3)C16—H16C0.9600
N7—H7N10.85 (3)O1W—H1WA0.81 (4)
N7—H7N20.82 (3)O1W—H1WB0.79 (4)
C1—C21.362 (2)
O1—N1—O2123.65 (18)C10—C7—C4120.21 (15)
O1—N1—C1118.37 (17)O5—C8—N3117.07 (15)
O2—N1—C1117.98 (18)O5—C8—C7125.47 (15)
O4—N2—O3123.20 (16)N3—C8—C7117.45 (15)
O4—N2—C3118.87 (15)O6—C9—N3121.57 (18)
O3—N2—C3117.82 (16)O6—C9—N4121.32 (18)
C9—N3—C8123.82 (15)N3—C9—N4117.11 (15)
C9—N3—C12117.94 (15)O7—C10—N4117.31 (16)
C8—N3—C12118.23 (15)O7—C10—C7126.12 (16)
C9—N4—C10123.82 (15)N4—C10—C7116.53 (15)
C9—N4—C11117.39 (16)N4—C11—H11A109.5
C10—N4—C11118.79 (16)N4—C11—H11B109.5
C15—N5—C16125.59 (17)H11A—C11—H11B109.5
C15—N5—C14110.50 (15)N4—C11—H11C109.5
C16—N5—C14123.85 (16)H11A—C11—H11C109.5
C15—N6—C13111.00 (17)H11B—C11—H11C109.5
C15—N6—H6N122.8 (17)N3—C12—H12A109.5
C13—N6—H6N125.9 (17)N3—C12—H12B109.5
C15—N7—H7N1120.1 (17)H12A—C12—H12B109.5
C15—N7—H7N2122.5 (19)N3—C12—H12C109.5
H7N1—N7—H7N2117 (2)H12A—C12—H12C109.5
C2—C1—C6121.62 (16)H12B—C12—H12C109.5
C2—C1—N1119.16 (17)O8—C13—N6125.8 (2)
C6—C1—N1119.21 (16)O8—C13—C14128.4 (2)
C1—C2—C3117.90 (16)N6—C13—C14105.78 (17)
C1—C2—H2121.0N5—C14—C13102.66 (16)
C3—C2—H2121.0N5—C14—H14A111.2
C2—C3—C4123.67 (16)C13—C14—H14A111.2
C2—C3—N2114.55 (15)N5—C14—H14B111.2
C4—C3—N2121.60 (15)C13—C14—H14B111.2
C3—C4—C5114.87 (15)H14A—C14—H14B109.1
C3—C4—C7124.65 (15)N7—C15—N5126.03 (18)
C5—C4—C7120.38 (15)N7—C15—N6123.96 (18)
C6—C5—C4122.91 (16)N5—C15—N6110.00 (18)
C6—C5—H5118.5N5—C16—H16A109.5
C4—C5—H5118.5N5—C16—H16B109.5
C5—C6—C1118.95 (16)H16A—C16—H16B109.5
C5—C6—H6120.5N5—C16—H16C109.5
C1—C6—H6120.5H16A—C16—H16C109.5
C8—C7—C10120.84 (15)H16B—C16—H16C109.5
C8—C7—C4118.68 (15)H1WA—O1W—H1WB115 (4)
O1—N1—C1—C2−8.0 (3)C10—C7—C8—N3−4.2 (2)
O2—N1—C1—C2172.15 (19)C4—C7—C8—N3−178.39 (15)
O1—N1—C1—C6173.55 (19)C8—N3—C9—O6−175.85 (19)
O2—N1—C1—C6−6.3 (3)C12—N3—C9—O65.2 (3)
C6—C1—C2—C30.7 (3)C8—N3—C9—N44.5 (3)
N1—C1—C2—C3−177.76 (16)C12—N3—C9—N4−174.44 (17)
C1—C2—C3—C41.8 (3)C10—N4—C9—O6179.29 (19)
C1—C2—C3—N2−173.48 (16)C11—N4—C9—O6−1.5 (3)
O4—N2—C3—C2139.47 (17)C10—N4—C9—N3−1.0 (3)
O3—N2—C3—C2−36.7 (2)C11—N4—C9—N3178.17 (19)
O4—N2—C3—C4−35.9 (2)C9—N4—C10—O7177.77 (18)
O3—N2—C3—C4147.96 (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—C5171.52 (15)C11—N4—C10—C7176.16 (18)
C2—C3—C4—C7172.93 (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—C62.8 (3)C8—C7—C10—N47.2 (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—C142.4 (2)
N1—C1—C6—C5177.25 (17)C15—N5—C14—C130.1 (2)
C3—C4—C7—C8−43.0 (2)C16—N5—C14—C13177.41 (18)
C5—C4—C7—C8133.16 (17)O8—C13—C14—N5178.1 (2)
C3—C4—C7—C10142.84 (18)N6—C13—C14—N5−1.5 (2)
C5—C4—C7—C10−41.0 (2)C16—N5—C15—N73.3 (3)
C9—N3—C8—O5179.40 (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—N61.4 (2)
C12—N3—C8—C7177.04 (16)C13—N6—C15—N7178.3 (2)
C10—C7—C8—O5174.36 (17)C13—N6—C15—N5−2.4 (2)
C4—C7—C8—O50.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N7—H7N1···O50.85 (3)1.96 (3)2.800 (2)171 (2)
N7—H7N2···O7i0.82 (3)1.95 (3)2.749 (2)165 (3)
N6—H6N···O1Wii0.84 (3)2.05 (3)2.767 (2)142 (2)
O1W—H1WA···O6iii0.81 (4)1.99 (4)2.792 (2)166 (4)
O1W—H1WB···O30.79 (4)2.47 (4)3.083 (3)136 (4)
O1W—H1WB···O8iv0.79 (4)2.61 (4)3.080 (3)120 (4)
C12—H12C···O5iii0.962.573.483 (3)159
C14—H14B···O1ii0.972.443.270 (3)144
C16—H16C···O50.962.543.248 (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.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N7—H7N1···O50.85 (3)1.96 (3)2.800 (2)171 (2)
N7—H7N2···O7i0.82 (3)1.95 (3)2.749 (2)165 (3)
N6—H6N···O1Wii0.84 (3)2.05 (3)2.767 (2)142 (2)
O1W—H1WA···O6iii0.81 (4)1.99 (4)2.792 (2)166 (4)
O1W—H1WB···O30.79 (4)2.47 (4)3.083 (3)136 (4)
O1W—H1WB···O8iv0.79 (4)2.61 (4)3.080 (3)120 (4)
C12—H12C···O5iii0.962.573.483 (3)159
C14—H14B···O1ii0.972.443.270 (3)144
C16—H16C···O50.962.543.248 (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 formulaC4H8N3O+·C12H9N4O7−·H2O
Mr453.38
Crystal system, space groupMonoclinic, 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)
Z4
Radiation typeMo Kα
µ (mm−1)0.13
Crystal size (mm)0.35 × 0.30 × 0.25
Data collection
DiffractometerBruker Kappa APEXII CCD Diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2004)
Tmin, Tmax0.954, 0.969
No. of measured, independent and
observed [I > 2σ(I)] reflections		32561, 5338, 3586
Rint0.037
(sin θ/λ)max (Å−1)0.699
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.051, 0.137, 1.03
No. of reflections5338
No. of parameters310
H-atom treatmentH 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.

References

First citationAltomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343–350.  CrossRef Web of Science IUCr Journals Google Scholar
 First citationBrown, D. J. (1962). The Chemistry of Heterocyclic Compounds, edited by. A. Weissberger, p. 16. New York: Interscience.  Google Scholar
 First citationBruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationFarrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationFisher, R. S., van Emde Boas, W., Blume, W., Elger, C., Genton, P., Lee, P. & Engel, J. Jr (2005). Epilepsia, 46, 470–472.  Web of Science CrossRef PubMed Google Scholar
 First citationGauthier, B. I., Tixier, R. & Uzan, A. (1963). Ann. Pharm. Fr. 21, 655–666.  PubMed CAS Google Scholar
 First citationGomathi, J. & Kalaivani, D. (2015). Acta Cryst. E71, 723–725.  Web of Science CSD CrossRef IUCr Journals Google Scholar
 First citationGroom, C. R. & Allen, F. H. (2014). Angew. Chem. Int. Ed. 53, 662–671.  Web of Science CSD CrossRef CAS Google Scholar
 First citationGunaseelan, S. & Doraisamyraja, K. (2014). Acta Cryst. E70, o1102–o1103.  CSD CrossRef IUCr Journals Google Scholar
 First citationJain, K. S., Chitre, T. S., Miniyar, P. B., Kathiravan, M. K., Bendre, V. S., Veer, V. S., Shahane, S. R. & Shishoo, C. J. (2006). Curr. Sci. 90, 793–803.  CAS Google Scholar
 First citationKalaivani, D. & Sridevi, G. (2015a). Private communication (refcode QUNRAU). CCDC, Cambridge, England.  Google Scholar
 First citationKalaivani, D. & Sridevi, G. (2015b). Private communication (refcode QUNROI). CCDC, Cambridge, England.  Google Scholar
 First citationKalaivani, D. & Sridevi, G. (2015c). Private communication (refcode QUNRUO). CCDC, Cambridge, England.  Google Scholar
 First citationKulkarni, S. K. (1999). Handbook of Experimental Pharamacology Vallabh Prakashan, Mumbai, p. 131.  Google Scholar
 First citationMacrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466–470.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
 First citationRajamani, K. & Kalaivani, D. (2015). Chem. Cent. J. 9, 1–12.  PubMed Google Scholar
 First citationSheldrick, G. M. (2015). Acta Cryst. C71, 3–8.  Web of Science CrossRef IUCr Journals Google Scholar
 First citationShorvon, S. D. (2004). The Treatment of Epilepsy. Oxford, UK: Blackwell Publishers.  Google Scholar
 First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSridevi, G. & Kalaivani, D. (2012). Acta Cryst. E68, o1044.  CSD CrossRef IUCr Journals Google Scholar
 First citationTripathi, K. D. (2009). Essentials of Medical Pharmacology, 6th ed., Chennai: Jaypee Brothers Medical Publishers.  Google Scholar
 First citationUeda, H. (1964). J. Chem. Phys. 40, 901–905.  CrossRef CAS Google Scholar
 First citationYadav, A. V. (2004). Pharmacology and Toxicology, 11th ed, pp. 57–67. Mumbai: Nirali Prakas.  Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 72| Part 5| May 2016| Pages 620-623
doi:10.1107/S2056989016005247
Follow Acta Cryst. E
Sign up for e-alerts
E-alerts
Follow Acta Cryst. on Twitter
Twitter
Follow us on facebook
Facebook
Sign up for RSS feeds
RSS