organic compounds
Diammonium 1,1′,3,3′-tetramethyl-2,2′,4,4′,6,6′-hexaoxoperhydro-5,5′-bipyrimidine-5,5′-diide monohydrate
aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bOrganic Chemistry Division, School of Science, VIT University, Vellore 632 014, India
*Correspondence e-mail: hkfun@usm.my
In the title hydrated salt, 2NH4+·C12H12N4O62−·H2O, the two hexahydropyrimidine rings in the dianion are inclined to one another at a dihedral angle of 62.76 (5)°. In the the anions and water molecules are linked into sheets parallel to the bc plane by intermolecular O—H⋯O hydrogen bonds and sustained by C—H⋯O contacts. The linking of the anions and water molecules with the cations by N—H⋯O hydrogen bonds creates a three-dimensional extended network. The is further stabilized by very weak C—H⋯π interactions.
Related literature
For general background to and applications of barbituric acid derivatives, see: Negwer (2001). For related structures, see: Rezende et al. (2005); da Silva et al. (2005). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2005); cell SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009).
Supporting information
https://doi.org/10.1107/S1600536809039968/tk2548sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809039968/tk2548Isup2.hkl
A solution of 1,3-dimethylbarbituric acid was refluxed in acetonitrile at 363 K for 2 h (monitored by TLC). After completion of the reaction, excess of solvent was distilled off. The solid product obtained was washed with mixture of ether and acetone, and dried. The purity of the crude product was checked through TLC and recrystallized using chloroform and benzene mixture. M.p. 515–517 K.
The H-atoms bound to atoms N5, N6 and O1W were located from the difference Fourier map and allowed to refine freely. The other H-atoms were placed in calculated positions, with C—H = 0.96 Å, Uiso = 1.5Ueq(C). Rotating models were used for the methyl groups. In the absence of significant
2042 Friedel pairs were merged for the final refinement.Barbituric acid derivatives show high hypnotic and sedative activity (Negwer, 2001).
The
of the title hydrated salt (I, Fig. 1) contains two ammonium cations, a 1,1',3,3'-tetramethyl-2,2',4,4',6,6'-hexaoxooctahydro-1H, 1'H-5,5'-bipyrimidine-5,5'-diide dianion and a water molecule. Two protons transfer from the C4 and C5 atoms to the ammonia molecules resulted in the formation of salts. The dianion is built up from one dimethylbarbiturate anion connected to the other one through the Csp3—Csp3 (C4—C5) bond. The two hexahydropyrimidine rings are essentially planar, with maximum deviations of 0.036 (1) Å for atom C1 and 0.018 (1) Å for atom N3, respectively, for rings with atom sequence C1/N1/C2/N2/C3/C4 and C5/C6/N3/C7/N4/C8. These two rings are inclined to one another at a dihedral angle of 62.76 (5)°. The bond lengths and angles are comparable to those found in related structures (Rezende et al., 2005; da Silva et al., 2005).The π contacts. Each ammonium H-atom participates in intermolecular hydrogen bonds. In the (Fig. 2), the anions and water molecules are linked into sheets parallel to the bc plane by O—H···O hydrogen bonds and sustained by C—H···O contacts (Table 1). The ammonium cations act as bridges between the anions and water molecules via N—H···O hydrogen bonds (Table 1) to create a three-dimensional extended network. The is further stabilized by weak intermolecular C10—H10C···Cg1 interactions (Table 1).
of (I) is mainly stabilized by a network of N—H···O, and O—H···O hydrogen bonds as well as C—H···O and C—H···For general background to and applications of barbituric acid derivatives, see: Negwer (2001). For related structures, see: Rezende et al. (2005); da Silva et al. (2005). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986). Cg1 is the centroid the the C1/N1/C2/N2/C3/C4 ring.
Data collection: APEX2 (Bruker, 2005); cell
SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsoids for non-H atoms and the atom-numbering scheme. | |
Fig. 2. The crystal structure of (I) viewed along the b axis, showing the three-dimensional network. H atoms not involved in intermolecular interactions (dashed lines) have been omitted for clarity. |
2NH4+·C12H12N4O62−·H2O | F(000) = 384 |
Mr = 362.36 | Dx = 1.523 Mg m−3 |
Monoclinic, Pc | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P -2yc | Cell parameters from 9975 reflections |
a = 8.5345 (1) Å | θ = 3.0–34.6° |
b = 12.1579 (2) Å | µ = 0.13 mm−1 |
c = 7.7482 (1) Å | T = 100 K |
β = 100.595 (1)° | Block, yellow |
V = 790.26 (2) Å3 | 0.46 × 0.24 × 0.20 mm |
Z = 2 |
Bruker SMART APEXII CCD area-detector diffractometer | 3387 independent reflections |
Radiation source: fine-focus sealed tube | 3237 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.026 |
φ and ω scans | θmax = 34.7°, θmin = 2.4° |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | h = −13→13 |
Tmin = 0.945, Tmax = 0.975 | k = −19→19 |
15091 measured reflections | l = −12→12 |
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)] = 0.029 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.083 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0579P)2 + 0.0092P] where P = (Fo2 + 2Fc2)/3 |
3387 reflections | (Δ/σ)max < 0.001 |
270 parameters | Δρmax = 0.41 e Å−3 |
2 restraints | Δρmin = −0.22 e Å−3 |
2NH4+·C12H12N4O62−·H2O | V = 790.26 (2) Å3 |
Mr = 362.36 | Z = 2 |
Monoclinic, Pc | Mo Kα radiation |
a = 8.5345 (1) Å | µ = 0.13 mm−1 |
b = 12.1579 (2) Å | T = 100 K |
c = 7.7482 (1) Å | 0.46 × 0.24 × 0.20 mm |
β = 100.595 (1)° |
Bruker SMART APEXII CCD area-detector diffractometer | 3387 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | 3237 reflections with I > 2σ(I) |
Tmin = 0.945, Tmax = 0.975 | Rint = 0.026 |
15091 measured reflections |
R[F2 > 2σ(F2)] = 0.029 | 2 restraints |
wR(F2) = 0.083 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.41 e Å−3 |
3387 reflections | Δρmin = −0.22 e Å−3 |
270 parameters |
Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1)K. |
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. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2sigma(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 1.03560 (11) | 0.14592 (7) | 1.07661 (12) | 0.01241 (15) | |
O2 | 1.29186 (11) | 0.47147 (8) | 1.22084 (12) | 0.01554 (17) | |
O3 | 0.81723 (11) | 0.48152 (7) | 0.83916 (11) | 0.01375 (16) | |
O4 | 0.58471 (11) | 0.32057 (7) | 0.97921 (12) | 0.01402 (16) | |
O5 | 0.41464 (11) | 0.06573 (8) | 0.55640 (12) | 0.01527 (17) | |
O6 | 0.94414 (10) | 0.14952 (7) | 0.66677 (12) | 0.01358 (16) | |
N1 | 1.16599 (12) | 0.30914 (8) | 1.13935 (13) | 0.01118 (16) | |
N2 | 1.05010 (13) | 0.47550 (7) | 1.03408 (14) | 0.01113 (16) | |
N3 | 0.50054 (11) | 0.19796 (8) | 0.76033 (12) | 0.01090 (16) | |
N4 | 0.67803 (12) | 0.11318 (8) | 0.60677 (13) | 0.01124 (16) | |
C1 | 1.03474 (13) | 0.24831 (9) | 1.05040 (14) | 0.00980 (17) | |
C2 | 1.17569 (14) | 0.42182 (9) | 1.13520 (15) | 0.01120 (18) | |
C3 | 0.92023 (13) | 0.42115 (9) | 0.93130 (15) | 0.01017 (17) | |
C4 | 0.91423 (13) | 0.30599 (9) | 0.93888 (15) | 0.00967 (17) | |
C5 | 0.77985 (13) | 0.24525 (9) | 0.83177 (14) | 0.00979 (18) | |
C6 | 0.62473 (13) | 0.25855 (9) | 0.86409 (14) | 0.01016 (17) | |
C7 | 0.52552 (13) | 0.12277 (9) | 0.63627 (15) | 0.01075 (18) | |
C8 | 0.80944 (13) | 0.17050 (9) | 0.70160 (15) | 0.01024 (17) | |
C9 | 1.29964 (15) | 0.25137 (11) | 1.24737 (16) | 0.0154 (2) | |
H9A | 1.3982 | 0.2837 | 1.2299 | 0.023* | |
H9B | 1.2972 | 0.1752 | 1.2142 | 0.023* | |
H9C | 1.2912 | 0.2573 | 1.3689 | 0.023* | |
C10 | 1.04993 (17) | 0.59583 (9) | 1.03645 (19) | 0.0170 (2) | |
H10A | 1.1471 | 0.6218 | 1.1073 | 0.025* | |
H10B | 0.9608 | 0.6216 | 1.0848 | 0.025* | |
H10C | 1.0418 | 0.6231 | 0.9189 | 0.025* | |
C11 | 0.34045 (15) | 0.20432 (11) | 0.80192 (18) | 0.0174 (2) | |
H11A | 0.2627 | 0.1952 | 0.6964 | 0.026* | |
H11B | 0.3261 | 0.2747 | 0.8530 | 0.026* | |
H11C | 0.3274 | 0.1472 | 0.8837 | 0.026* | |
C12 | 0.70481 (16) | 0.04107 (12) | 0.46407 (19) | 0.0201 (2) | |
H12A | 0.6055 | 0.0087 | 0.4092 | 0.030* | |
H12B | 0.7785 | −0.0159 | 0.5103 | 0.030* | |
H12C | 0.7480 | 0.0831 | 0.3789 | 0.030* | |
N5 | 0.08583 (12) | 0.04901 (9) | 0.41174 (14) | 0.01257 (17) | |
H1N5 | 0.061 (3) | −0.020 (2) | 0.410 (3) | 0.027 (6)* | |
H2N5 | 0.067 (3) | 0.083 (2) | 0.315 (3) | 0.029 (5)* | |
H3N5 | 0.195 (3) | 0.0572 (17) | 0.456 (3) | 0.020 (5)* | |
H4N5 | 0.035 (3) | 0.0832 (18) | 0.486 (3) | 0.025 (5)* | |
N6 | 0.56158 (13) | 0.46002 (9) | 0.56578 (14) | 0.01434 (18) | |
H1N6 | 0.566 (3) | 0.4075 (16) | 0.488 (3) | 0.016 (4)* | |
H2N6 | 0.465 (3) | 0.4638 (17) | 0.604 (3) | 0.022 (5)* | |
H3N6 | 0.568 (3) | 0.5221 (19) | 0.520 (3) | 0.023 (5)* | |
H4N6 | 0.641 (3) | 0.4479 (18) | 0.654 (3) | 0.023 (5)* | |
O1W | 0.69194 (13) | 0.30906 (8) | 0.33669 (14) | 0.01932 (18) | |
H1W1 | 0.753 (3) | 0.364 (2) | 0.346 (3) | 0.026 (5)* | |
H2W1 | 0.667 (3) | 0.297 (2) | 0.236 (4) | 0.033 (6)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0146 (4) | 0.0091 (3) | 0.0126 (3) | 0.0000 (3) | 0.0001 (3) | 0.0007 (3) |
O2 | 0.0123 (4) | 0.0164 (4) | 0.0170 (4) | −0.0048 (3) | 0.0002 (3) | −0.0031 (3) |
O3 | 0.0144 (4) | 0.0107 (3) | 0.0147 (4) | 0.0010 (3) | −0.0010 (3) | 0.0005 (3) |
O4 | 0.0141 (4) | 0.0137 (4) | 0.0147 (4) | 0.0001 (3) | 0.0039 (3) | −0.0042 (3) |
O5 | 0.0098 (3) | 0.0165 (4) | 0.0179 (4) | −0.0020 (3) | −0.0017 (3) | −0.0043 (3) |
O6 | 0.0096 (3) | 0.0153 (4) | 0.0158 (4) | 0.0003 (3) | 0.0024 (3) | −0.0037 (3) |
N1 | 0.0091 (4) | 0.0118 (4) | 0.0117 (4) | −0.0009 (3) | −0.0005 (3) | −0.0001 (3) |
N2 | 0.0107 (4) | 0.0087 (3) | 0.0133 (4) | −0.0016 (3) | 0.0002 (3) | −0.0012 (3) |
N3 | 0.0081 (4) | 0.0126 (4) | 0.0119 (4) | 0.0000 (3) | 0.0016 (3) | −0.0014 (3) |
N4 | 0.0092 (4) | 0.0112 (4) | 0.0128 (4) | −0.0003 (3) | 0.0009 (3) | −0.0041 (3) |
C1 | 0.0086 (4) | 0.0109 (4) | 0.0098 (4) | −0.0006 (3) | 0.0014 (3) | −0.0008 (3) |
C2 | 0.0105 (4) | 0.0122 (4) | 0.0110 (4) | −0.0027 (4) | 0.0025 (3) | −0.0010 (3) |
C3 | 0.0098 (4) | 0.0103 (4) | 0.0102 (4) | −0.0009 (3) | 0.0015 (3) | −0.0010 (3) |
C4 | 0.0090 (4) | 0.0090 (4) | 0.0104 (4) | −0.0004 (3) | 0.0001 (3) | −0.0015 (3) |
C5 | 0.0097 (4) | 0.0089 (4) | 0.0102 (4) | −0.0004 (3) | 0.0002 (3) | −0.0011 (3) |
C6 | 0.0100 (4) | 0.0092 (4) | 0.0107 (4) | −0.0006 (3) | 0.0004 (3) | 0.0001 (3) |
C7 | 0.0096 (4) | 0.0095 (4) | 0.0124 (4) | −0.0003 (3) | 0.0001 (3) | −0.0002 (3) |
C8 | 0.0101 (4) | 0.0090 (4) | 0.0109 (4) | −0.0009 (3) | 0.0001 (3) | −0.0003 (3) |
C9 | 0.0112 (4) | 0.0172 (5) | 0.0160 (5) | 0.0002 (4) | −0.0023 (4) | 0.0023 (4) |
C10 | 0.0188 (5) | 0.0099 (4) | 0.0211 (5) | −0.0024 (4) | 0.0004 (4) | −0.0014 (4) |
C11 | 0.0102 (5) | 0.0222 (6) | 0.0204 (5) | −0.0007 (4) | 0.0044 (4) | −0.0033 (4) |
C12 | 0.0133 (5) | 0.0243 (6) | 0.0224 (6) | −0.0025 (4) | 0.0027 (4) | −0.0145 (5) |
N5 | 0.0120 (4) | 0.0126 (4) | 0.0130 (4) | −0.0014 (3) | 0.0018 (3) | 0.0006 (3) |
N6 | 0.0141 (4) | 0.0137 (4) | 0.0147 (4) | −0.0007 (3) | 0.0013 (3) | 0.0008 (3) |
O1W | 0.0220 (5) | 0.0170 (4) | 0.0176 (4) | −0.0044 (3) | 0.0001 (3) | −0.0003 (3) |
O1—C1 | 1.2611 (14) | C9—H9A | 0.9600 |
O2—C2 | 1.2433 (14) | C9—H9B | 0.9600 |
O3—C3 | 1.2611 (14) | C9—H9C | 0.9600 |
O4—C6 | 1.2620 (14) | C10—H10A | 0.9600 |
O5—C7 | 1.2427 (13) | C10—H10B | 0.9600 |
O6—C8 | 1.2544 (14) | C10—H10C | 0.9600 |
N1—C2 | 1.3733 (15) | C11—H11A | 0.9600 |
N1—C1 | 1.4117 (14) | C11—H11B | 0.9600 |
N1—C9 | 1.4642 (15) | C11—H11C | 0.9600 |
N2—C2 | 1.3710 (15) | C12—H12A | 0.9600 |
N2—C3 | 1.4052 (15) | C12—H12B | 0.9600 |
N2—C10 | 1.4631 (14) | C12—H12C | 0.9600 |
N3—C7 | 1.3713 (15) | N5—H1N5 | 0.86 (2) |
N3—C6 | 1.4139 (14) | N5—H2N5 | 0.85 (3) |
N3—C11 | 1.4623 (15) | N5—H3N5 | 0.94 (2) |
N4—C7 | 1.3672 (15) | N5—H4N5 | 0.89 (2) |
N4—C8 | 1.4072 (14) | N6—H1N6 | 0.88 (2) |
N4—C12 | 1.4616 (16) | N6—H2N6 | 0.93 (2) |
C1—C4 | 1.4033 (15) | N6—H3N6 | 0.84 (2) |
C3—C4 | 1.4028 (15) | N6—H4N6 | 0.88 (2) |
C4—C5 | 1.4830 (15) | O1W—H1W1 | 0.84 (3) |
C5—C6 | 1.4013 (15) | O1W—H2W1 | 0.79 (3) |
C5—C8 | 1.4143 (15) | ||
C2—N1—C1 | 123.86 (10) | N1—C9—H9B | 109.5 |
C2—N1—C9 | 116.61 (10) | H9A—C9—H9B | 109.5 |
C1—N1—C9 | 119.51 (10) | N1—C9—H9C | 109.5 |
C2—N2—C3 | 123.53 (9) | H9A—C9—H9C | 109.5 |
C2—N2—C10 | 118.11 (10) | H9B—C9—H9C | 109.5 |
C3—N2—C10 | 118.34 (10) | N2—C10—H10A | 109.5 |
C7—N3—C6 | 123.30 (9) | N2—C10—H10B | 109.5 |
C7—N3—C11 | 117.50 (10) | H10A—C10—H10B | 109.5 |
C6—N3—C11 | 118.70 (9) | N2—C10—H10C | 109.5 |
C7—N4—C8 | 124.21 (9) | H10A—C10—H10C | 109.5 |
C7—N4—C12 | 117.63 (10) | H10B—C10—H10C | 109.5 |
C8—N4—C12 | 118.14 (10) | N3—C11—H11A | 109.5 |
O1—C1—C4 | 125.05 (10) | N3—C11—H11B | 109.5 |
O1—C1—N1 | 117.25 (10) | H11A—C11—H11B | 109.5 |
C4—C1—N1 | 117.69 (9) | N3—C11—H11C | 109.5 |
O2—C2—N2 | 122.47 (10) | H11A—C11—H11C | 109.5 |
O2—C2—N1 | 121.16 (11) | H11B—C11—H11C | 109.5 |
N2—C2—N1 | 116.36 (10) | N4—C12—H12A | 109.5 |
O3—C3—C4 | 125.29 (10) | N4—C12—H12B | 109.5 |
O3—C3—N2 | 116.25 (10) | H12A—C12—H12B | 109.5 |
C4—C3—N2 | 118.46 (10) | N4—C12—H12C | 109.5 |
C3—C4—C1 | 119.76 (10) | H12A—C12—H12C | 109.5 |
C3—C4—C5 | 120.26 (9) | H12B—C12—H12C | 109.5 |
C1—C4—C5 | 119.97 (9) | H1N5—N5—H2N5 | 117 (2) |
C6—C5—C8 | 120.00 (9) | H1N5—N5—H3N5 | 109.6 (19) |
C6—C5—C4 | 120.09 (9) | H2N5—N5—H3N5 | 107 (2) |
C8—C5—C4 | 119.86 (10) | H1N5—N5—H4N5 | 108 (2) |
O4—C6—C5 | 125.63 (10) | H2N5—N5—H4N5 | 108 (2) |
O4—C6—N3 | 116.18 (10) | H3N5—N5—H4N5 | 107 (2) |
C5—C6—N3 | 118.19 (9) | H1N6—N6—H2N6 | 113.9 (19) |
O5—C7—N4 | 122.03 (11) | H1N6—N6—H3N6 | 110.3 (19) |
O5—C7—N3 | 121.25 (10) | H2N6—N6—H3N6 | 103 (2) |
N4—C7—N3 | 116.71 (10) | H1N6—N6—H4N6 | 106.3 (19) |
O6—C8—N4 | 117.44 (10) | H2N6—N6—H4N6 | 111 (2) |
O6—C8—C5 | 125.09 (10) | H3N6—N6—H4N6 | 112 (2) |
N4—C8—C5 | 117.44 (10) | H1W1—O1W—H2W1 | 106 (3) |
N1—C9—H9A | 109.5 | ||
C2—N1—C1—O1 | −174.49 (10) | C3—C4—C5—C8 | 117.68 (12) |
C9—N1—C1—O1 | 3.76 (15) | C1—C4—C5—C8 | −63.31 (14) |
C2—N1—C1—C4 | 5.98 (15) | C8—C5—C6—O4 | 178.22 (11) |
C9—N1—C1—C4 | −175.76 (10) | C4—C5—C6—O4 | 0.76 (17) |
C3—N2—C2—O2 | 177.67 (11) | C8—C5—C6—N3 | −1.73 (15) |
C10—N2—C2—O2 | −3.67 (17) | C4—C5—C6—N3 | −179.19 (9) |
C3—N2—C2—N1 | −3.18 (16) | C7—N3—C6—O4 | −176.44 (10) |
C10—N2—C2—N1 | 175.47 (10) | C11—N3—C6—O4 | −4.80 (15) |
C1—N1—C2—O2 | 177.56 (10) | C7—N3—C6—C5 | 3.52 (15) |
C9—N1—C2—O2 | −0.74 (16) | C11—N3—C6—C5 | 175.16 (10) |
C1—N1—C2—N2 | −1.60 (16) | C8—N4—C7—O5 | −175.66 (11) |
C9—N1—C2—N2 | −179.90 (10) | C12—N4—C7—O5 | 6.19 (17) |
C2—N2—C3—O3 | −176.92 (10) | C8—N4—C7—N3 | 3.66 (16) |
C10—N2—C3—O3 | 4.43 (16) | C12—N4—C7—N3 | −174.49 (11) |
C2—N2—C3—C4 | 3.31 (17) | C6—N3—C7—O5 | 174.96 (10) |
C10—N2—C3—C4 | −175.34 (10) | C11—N3—C7—O5 | 3.22 (16) |
O3—C3—C4—C1 | −178.39 (11) | C6—N3—C7—N4 | −4.37 (15) |
N2—C3—C4—C1 | 1.36 (16) | C11—N3—C7—N4 | −176.11 (10) |
O3—C3—C4—C5 | 0.63 (18) | C7—N4—C8—O6 | 176.38 (10) |
N2—C3—C4—C5 | −179.62 (9) | C12—N4—C8—O6 | −5.48 (16) |
O1—C1—C4—C3 | 174.85 (11) | C7—N4—C8—C5 | −2.08 (16) |
N1—C1—C4—C3 | −5.66 (15) | C12—N4—C8—C5 | 176.06 (11) |
O1—C1—C4—C5 | −4.17 (17) | C6—C5—C8—O6 | −177.28 (11) |
N1—C1—C4—C5 | 175.32 (9) | C4—C5—C8—O6 | 0.18 (17) |
C3—C4—C5—C6 | −64.86 (14) | C6—C5—C8—N4 | 1.05 (15) |
C1—C4—C5—C6 | 114.15 (12) | C4—C5—C8—N4 | 178.51 (10) |
D—H···A | D—H | H···A | D···A | D—H···A |
N5—H1N5···O1i | 0.87 (2) | 2.04 (2) | 2.7629 (14) | 141 (2) |
N5—H1N5···O6i | 0.87 (2) | 2.52 (2) | 3.1697 (14) | 132.9 (19) |
N5—H2N5···O1ii | 0.85 (2) | 1.97 (2) | 2.8116 (14) | 173 (2) |
N5—H3N5···O5 | 0.94 (3) | 1.90 (3) | 2.8312 (14) | 176.1 (19) |
N5—H4N5···O6iii | 0.89 (2) | 1.90 (2) | 2.7819 (14) | 173 (2) |
N6—H1N6···O1W | 0.88 (2) | 2.10 (2) | 2.9126 (15) | 152 (2) |
N6—H2N6···O2iv | 0.93 (3) | 2.03 (2) | 2.9074 (15) | 157.8 (19) |
N6—H3N6···O4v | 0.84 (2) | 1.95 (2) | 2.7665 (14) | 164 (2) |
N6—H4N6···O3 | 0.88 (2) | 1.92 (2) | 2.7597 (14) | 158 (2) |
O1W—H1W1···O3v | 0.84 (3) | 1.96 (2) | 2.7602 (13) | 158 (2) |
O1W—H2W1···O4vi | 0.78 (3) | 2.01 (3) | 2.7563 (14) | 161 (3) |
C9—H9A···O1Wvii | 0.96 | 2.51 | 3.3658 (17) | 148 |
C10—H10C···Cg1v | 0.96 | 2.96 | 3.8822 (15) | 162 |
Symmetry codes: (i) x−1, −y, z−1/2; (ii) x−1, y, z−1; (iii) x−1, y, z; (iv) x−1, −y+1, z−1/2; (v) x, −y+1, z−1/2; (vi) x, y, z−1; (vii) x+1, y, z+1. |
Experimental details
Crystal data | |
Chemical formula | 2NH4+·C12H12N4O62−·H2O |
Mr | 362.36 |
Crystal system, space group | Monoclinic, Pc |
Temperature (K) | 100 |
a, b, c (Å) | 8.5345 (1), 12.1579 (2), 7.7482 (1) |
β (°) | 100.595 (1) |
V (Å3) | 790.26 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.13 |
Crystal size (mm) | 0.46 × 0.24 × 0.20 |
Data collection | |
Diffractometer | Bruker SMART APEXII CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2005) |
Tmin, Tmax | 0.945, 0.975 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 15091, 3387, 3237 |
Rint | 0.026 |
(sin θ/λ)max (Å−1) | 0.800 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.029, 0.083, 1.05 |
No. of reflections | 3387 |
No. of parameters | 270 |
No. of restraints | 2 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.41, −0.22 |
Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N5—H1N5···O1i | 0.87 (2) | 2.04 (2) | 2.7629 (14) | 141 (2) |
N5—H1N5···O6i | 0.87 (2) | 2.52 (2) | 3.1697 (14) | 132.9 (19) |
N5—H2N5···O1ii | 0.85 (2) | 1.97 (2) | 2.8116 (14) | 173 (2) |
N5—H3N5···O5 | 0.94 (3) | 1.90 (3) | 2.8312 (14) | 176.1 (19) |
N5—H4N5···O6iii | 0.89 (2) | 1.90 (2) | 2.7819 (14) | 173 (2) |
N6—H1N6···O1W | 0.88 (2) | 2.10 (2) | 2.9126 (15) | 152 (2) |
N6—H2N6···O2iv | 0.93 (3) | 2.03 (2) | 2.9074 (15) | 157.8 (19) |
N6—H3N6···O4v | 0.84 (2) | 1.95 (2) | 2.7665 (14) | 164 (2) |
N6—H4N6···O3 | 0.88 (2) | 1.92 (2) | 2.7597 (14) | 158 (2) |
O1W—H1W1···O3v | 0.84 (3) | 1.96 (2) | 2.7602 (13) | 158 (2) |
O1W—H2W1···O4vi | 0.78 (3) | 2.01 (3) | 2.7563 (14) | 161 (3) |
C9—H9A···O1Wvii | 0.9600 | 2.5100 | 3.3658 (17) | 148.00 |
C10—H10C···Cg1v | 0.9600 | 2.96 | 3.8822 (15) | 162 |
Symmetry codes: (i) x−1, −y, z−1/2; (ii) x−1, y, z−1; (iii) x−1, y, z; (iv) x−1, −y+1, z−1/2; (v) x, −y+1, z−1/2; (vi) x, y, z−1; (vii) x+1, y, z+1. |
Footnotes
‡Thomson Reuters ResearcherID: A-3561-2009.
Acknowledgements
HKF and JHG thank Universiti Sains Malaysia (USM) for a Research University Golden Goose Grant (No. 1001/PFIZIK/811012). JHG thanks USM for the award of a USM Fellowship. VV is grateful to DST-India for funding through the Young Scientist Scheme (Fast Track Proposal).
References
Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105–107. CrossRef CAS Web of Science IUCr Journals Google Scholar
Negwer, M. (2001). Organic-Chemical Drugs and their Synonyms, 7th Rev. and Engl. Ed., Vol. 4, pp. 2873–2957. Berlin: Akademie. Google Scholar
Rezende, M. C., Dominguez, M., Wardell, J. L., Skakle, J. M. S., Low, J. N. & Glidewell, C. (2005). Acta Cryst. C61, o306–o311. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Silva, E. T. da, Ribiero, R. S., Lima, E. L. S., Wardell, J. L., Skakle, J. M. S., Low, J. N. & Glidewell, C. (2005). Acta Cryst. C61, o15–o20. Web of Science CSD CrossRef IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
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Barbituric acid derivatives show high hypnotic and sedative activity (Negwer, 2001).
The asymmetric unit of the title hydrated salt (I, Fig. 1) contains two ammonium cations, a 1,1',3,3'-tetramethyl-2,2',4,4',6,6'-hexaoxooctahydro-1H, 1'H-5,5'-bipyrimidine-5,5'-diide dianion and a water molecule. Two protons transfer from the C4 and C5 atoms to the ammonia molecules resulted in the formation of salts. The dianion is built up from one dimethylbarbiturate anion connected to the other one through the Csp3—Csp3 (C4—C5) bond. The two hexahydropyrimidine rings are essentially planar, with maximum deviations of 0.036 (1) Å for atom C1 and 0.018 (1) Å for atom N3, respectively, for rings with atom sequence C1/N1/C2/N2/C3/C4 and C5/C6/N3/C7/N4/C8. These two rings are inclined to one another at a dihedral angle of 62.76 (5)°. The bond lengths and angles are comparable to those found in related structures (Rezende et al., 2005; da Silva et al., 2005).
The crystal structure of (I) is mainly stabilized by a network of N—H···O, and O—H···O hydrogen bonds as well as C—H···O and C—H···π contacts. Each ammonium H-atom participates in intermolecular hydrogen bonds. In the crystal structure (Fig. 2), the anions and water molecules are linked into sheets parallel to the bc plane by O—H···O hydrogen bonds and sustained by C—H···O contacts (Table 1). The ammonium cations act as bridges between the anions and water molecules via N—H···O hydrogen bonds (Table 1) to create a three-dimensional extended network. The crystal structure is further stabilized by weak intermolecular C10—H10C···Cg1 interactions (Table 1).