N1,N4,3,6-Tetra­methyl-1,2,4,5-tetra­zine-1,4-dicarboxamide

Sun, N.-B.; Rao, G.-W.; Shen, Q.

doi:10.1107/S1600536812022519

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 6| June 2012| Pages o1841-o1842

doi:10.1107/S1600536812022519

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N¹,N⁴,3,6-Tetramethyl-1,2,4,5-tetrazine-1,4-dicarboxamide

Na-Bo Sun,^a Guo-Wu Rao ^b ^* and Qun Shen ^c

^aCollege of Biology and Environmental Engineering, Zhejiang Shuren University, Hangzhou 310015, People's Republic of China, ^bCollege of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China, and ^cHangzhou Institute of Calibration and Testing for Quality and Technical Supervision, Hangzhou 310019, People's Republic of China
^*Correspondence e-mail: rgw@zjut.edu.cn

(Received 6 May 2012; accepted 17 May 2012; online 23 May 2012)

The asymmetric unit of the title compound, C₈H₁₄N₆O₂, contains two independent molecules. In one molecule, the amide-substituted N atoms of the tetrazine ring deviate from the plane [maximum deviation = 0.028 (1) Å] through the four other atoms in the ring by 0.350 (2) and 0.344 (2) Å, forming a boat conformation, and the mean planes of the two carboxamide groups form dihedral angles of 10.46 (13) and 20.41 (12)° with the four approximtely planar atoms in the tetrazine ring. In the other molecule, the amide-substituted N atoms of the tetrazine ring deviate from the plane [maximum deviation = 0.033 (1) Å] through the four other atoms in the ring by 0.324 (2) and 0.307 (2) Å, forming a boat conformation, and the mean planes of the two carboxamide groups form dihedral angles of 14.66 (11) and 17.08 (10)° with the four approximately planar atoms of the tetrazine ring. In the crystal, N—H⋯O hydrogen bonds connect molecules to form a two-dimensional network parallel to (1-1-1). Intramolecular N—H⋯N hydrogen bonds are observed.

Related literature

For chemical reactions of 1,2,4,5-tetrazine derivatives, see: Domingo et al. (2009 ); Lorincz et al. (2010 ) and for their biological activity, see: Devaraj et al. (2009 ); Eremeev et al. (1978 , 1980 ); Han et al. (2010 ); Neunhoeffer (1984 ); Sauer (1996 ). For the antitumor activity of 1,2,4,5-tetrazine derivatives, see: Hu et al. (2002 , 2004 ); Rao & Hu (2005 , 2006 ). For standard bond lengths, see: Allen et al. (1987 ). For the synthesis of the title compound, see: Hu et al. (2004); Rao et al. (2012 ); Sun et al. (2003 ).

Experimental

Crystal data

C₈H₁₄N₆O₂
M_r = 226.25
Triclinic, $[P \overline 1]$
a = 9.0002 (17) Å
b = 12.045 (2) Å
c = 12.357 (2) Å
α = 118.386 (2)°
β = 101.701 (3)°
γ = 99.494 (3)°
V = 1099.6 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 298 K
0.34 × 0.30 × 0.15 mm

Data collection

Bruker SMART CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1997 ) T_min = 0.966, T_max = 0.985
5571 measured reflections
3809 independent reflections
3178 reflections with I > 2σ(I)
R_int = 0.018

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.115
S = 1.06
3809 reflections
298 parameters
H-atom parameters constrained
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3⋯N2	0.86	2.16	2.572 (2)	108
N6—H6⋯N5	0.86	2.19	2.586 (2)	108
N9—H9⋯N8	0.86	2.15	2.567 (2)	109
N12—H12⋯N11	0.86	2.17	2.581 (2)	109
N3—H3⋯O4	0.86	2.20	2.925 (2)	142
N6—H6⋯O3ⁱ	0.86	2.16	2.918 (2)	146
N9—H9⋯O1ⁱⁱ	0.86	2.14	2.877 (3)	143
N12—H12⋯O2ⁱⁱⁱ	0.86	2.24	2.967 (3)	142
Symmetry codes: (i) x-1, y, z-1; (ii) -x+1, -y+1, -z+1; (iii) -x+2, -y+2, -z+1.

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812022519/lh5475sup1.cif

Supporting information file. DOI: 10.1107/S1600536812022519/lh5475Isup2.cdx

Structure factors: contains datablock I. DOI: 10.1107/S1600536812022519/lh5475Isup3.hkl

Supporting information file. DOI: 10.1107/S1600536812022519/lh5475Isup4.cml

checkCIF report

Comment top

Tetrazine derivatives have high activity in chemical reactions (Domingo et al., 2009; Lorincz et al., 2010), and have been widely used in pesticides and medicines (Devaraj et al., 2009; Eremeev et al.,1978, 1980; Han et al., 2010; Neunhoeffer, 1984; Sauer, 1996). In a continuation of our studies of antitumor activities in 1,2,4,5-tetrazine derivatives (Hu et al., 2002, 2004; Rao & Hu, 2005, 2006), we have obtained a colourless crystalline compound, (I). The structure was confirmed by single-crystal X-ray diffraction.

The two molecules forming the asymmetric unit of (I) are shown in Fig. 1. The C=N, N—N and C—N bonds have normal distances (Allen et al., 1987). The tetrazine rings are 1,4-dihydro structure with the N-substituted groups at the 1,4-positions.

In (I), atoms N2, C3, N5 and C6 are approximately planar, with the largest deviation from this plane being 0.028 (1) Å. Atoms N1 and N4 deviate from this plane by 0.350 (2) and 0.344 (2) Å, respectively. Atoms N8, C9, N11 and C12 are approximately planar, with the largest deviation from this plane being 0.033 (1) Å. Atoms N7 and N10 deviate from this plane by 0.324 (2) and 0.307 (2) Å, respectively. The dihedral angle between the N2/C3/N5/C6 plane and the N1/N2/C6 plane is 27.99 (16)°, and between the N2/C3/N5/C6 plane and the N4/N5/C3 plane is 27.91 (16)°. The dihedral angle between the N8/C9/N11/C12 plane and the N7/N8/C12 plane is 26.36 (14)°, and between the N8/C9/N11/C12 plane and the N10/N11/C9 plane is 24.96 (13)°. The tetrazine ring exhibits a boat conformation. Atoms O1, C4, N3 and C7 are approximately planar, with the largest deviation from this plane being 0.016 (1) Å. Atoms O2, C5, N6 and C8 are approximately planar, with the largest deviation from this plane being -0.022 (1) Å. Atoms O3, C13, N9 and C15 are approximately planar, with the largest deviation from this plane being 0.004 (1) Å. Atoms O4, C14, N12 and C16 are approximately planar, with the largest deviation from this plane being -0.005 (1) Å. The dihedral angles between the N2/C3/N5/C6 plane and two planes of carboxamide groups are 10.46 (13) and 20.41 (12)°, respectively. The dihedral angles between the N8/C9/N11/C12 plane and two planes of carboxamide groups are 14.66 (11) and 17.08 (10)°, respectively. Intramolecular N—H···N hydrogen bonds are observed. In the crystal, N—H···O hydrogen bonds connect molecules to form a two-dimensional network parallel to (111) (Fig. 2).

Related literature top

For chemical reactions of 1,2,4,5-tetrazine derivatives, see: Domingo et al. (2009); Lorincz et al. (2010) and for their biological activity, see: Devaraj et al. (2009); Eremeev et al. (1978, 1980); Han et al. (2010); Neunhoeffer (1984); Sauer (1996). For the antitumor activity of 1,2,4,5-tetrazine derivatives, see: Hu et al. (2002, 2004); Rao & Hu (2005, 2006). For standard bond lengths, see: Allen et al. (1987). For the synthesis of the title compound, see: Hu et al. (2004); Rao et al. (2012); Sun et al. (2003).

Experimental top

The title compound was the product of the reaction of 3,6-dimethyl-1,6-dihydro-1,2,4,5-tetrazine, bis(trichloromethyl) carbonate and methanamine according to the procedure (Hu et al., 2004; Rao et al., 2012; Sun et al., 2003). A solution of the compound in ethanol was concentrated gradually at room temperature to afford colourless blocks.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The molecular structure of (I), shown with 30% probability displacement ellipsoids. Hydrogen bonds are shown as dashed lines.
	Fig. 2. Part of the crystal structure with hydrogen donds shown as dashed lines.

N¹,N⁴,3,6-Tetramethyl-1,2,4,5-tetrazine-1,4-dicarboxamide top

Crystal data top

C₈H₁₄N₆O₂	Z = 4
M_r = 226.25	F(000) = 480
Triclinic, P1	D_x = 1.367 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 9.0002 (17) Å	Cell parameters from 2161 reflections
b = 12.045 (2) Å	θ = 2.4–26.0°
c = 12.357 (2) Å	µ = 0.10 mm⁻¹
α = 118.386 (2)°	T = 298 K
β = 101.701 (3)°	Block, colourless
γ = 99.494 (3)°	0.34 × 0.30 × 0.15 mm
V = 1099.6 (4) Å³

Data collection top

Bruker SMART CCD diffractometer	3809 independent reflections
Radiation source: fine-focus sealed tube	3178 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.018
ϕ and ω scans	θ_max = 25.0°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 1997)	h = −10→10
T_min = 0.966, T_max = 0.985	k = −14→11
5571 measured reflections	l = −11→14

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.044	H-atom parameters constrained
wR(F²) = 0.115	w = 1/[σ²(F_o²) + (0.0511P)² + 0.2386P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max < 0.001
3809 reflections	Δρ_max = 0.17 e Å⁻³
298 parameters	Δρ_min = −0.19 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.028 (2)

Crystal data top

C₈H₁₄N₆O₂	γ = 99.494 (3)°
M_r = 226.25	V = 1099.6 (4) Å³
Triclinic, P1	Z = 4
a = 9.0002 (17) Å	Mo Kα radiation
b = 12.045 (2) Å	µ = 0.10 mm⁻¹
c = 12.357 (2) Å	T = 298 K
α = 118.386 (2)°	0.34 × 0.30 × 0.15 mm
β = 101.701 (3)°

Data collection top

Bruker SMART CCD diffractometer	3809 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1997)	3178 reflections with I > 2σ(I)
T_min = 0.966, T_max = 0.985	R_int = 0.018
5571 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	0 restraints
wR(F²) = 0.115	H-atom parameters constrained
S = 1.06	Δρ_max = 0.17 e Å⁻³
3809 reflections	Δρ_min = −0.19 e Å⁻³
298 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O2	0.65578 (15)	1.05745 (12)	0.47718 (12)	0.0481 (3)
O4	0.89425 (15)	0.52517 (12)	0.38657 (12)	0.0485 (3)
O3	1.24324 (16)	0.92428 (15)	1.04950 (13)	0.0591 (4)
O1	0.31715 (16)	0.38004 (14)	0.09001 (15)	0.0624 (4)
N11	1.11229 (17)	0.83375 (14)	0.67258 (14)	0.0413 (4)
N5	0.42071 (17)	0.76464 (15)	0.18158 (14)	0.0428 (4)
N8	0.90988 (17)	0.73177 (15)	0.76534 (14)	0.0441 (4)
N1	0.48121 (17)	0.59229 (14)	0.19776 (14)	0.0427 (4)
N4	0.54445 (17)	0.84531 (14)	0.30278 (14)	0.0408 (4)
N2	0.64314 (17)	0.67031 (15)	0.26959 (15)	0.0456 (4)
N10	0.99591 (17)	0.70658 (13)	0.59312 (13)	0.0401 (4)
N7	1.06880 (17)	0.81490 (15)	0.84255 (14)	0.0424 (4)
C5	0.5569 (2)	0.98150 (17)	0.36969 (17)	0.0389 (4)
C9	0.8816 (2)	0.67574 (17)	0.64282 (17)	0.0389 (4)
N12	1.10612 (19)	0.69002 (15)	0.43553 (14)	0.0459 (4)
H12	1.1731	0.7660	0.4950	0.055*
C12	1.1485 (2)	0.88147 (16)	0.79504 (16)	0.0378 (4)
N3	0.57057 (19)	0.42708 (15)	0.20694 (15)	0.0479 (4)
H3	0.6588	0.4886	0.2591	0.058*
C4	0.4495 (2)	0.45756 (18)	0.15889 (17)	0.0432 (4)
N6	0.45245 (19)	1.01525 (15)	0.30820 (15)	0.0470 (4)
H6	0.3919	0.9577	0.2297	0.056*
N9	0.99787 (19)	0.79818 (17)	1.00444 (15)	0.0511 (4)
H9	0.9073	0.7470	0.9458	0.061*
C14	0.9928 (2)	0.63353 (17)	0.46360 (16)	0.0379 (4)
C3	0.6682 (2)	0.79506 (18)	0.32349 (17)	0.0408 (4)
C13	1.1104 (2)	0.85187 (18)	0.97372 (17)	0.0425 (4)
C6	0.3891 (2)	0.64048 (18)	0.13459 (17)	0.0394 (4)
C10	0.7187 (2)	0.5826 (2)	0.55809 (19)	0.0531 (5)
H10A	0.6737	0.6075	0.4987	0.080*
H10B	0.6527	0.5861	0.6110	0.080*
H10C	0.7249	0.4941	0.5100	0.080*
C11	1.2743 (2)	1.01175 (18)	0.88275 (18)	0.0505 (5)
H11A	1.2369	1.0699	0.9493	0.076*
H11B	1.2985	1.0501	0.8334	0.076*
H11C	1.3685	0.9993	0.9221	0.076*
C1	0.8344 (2)	0.88257 (19)	0.4028 (2)	0.0555 (5)
H1A	0.8627	0.9432	0.3753	0.083*
H1B	0.9055	0.8296	0.3914	0.083*
H1C	0.8422	0.9314	0.4929	0.083*
C2	0.2535 (2)	0.5519 (2)	0.01109 (18)	0.0531 (5)
H2A	0.2876	0.4846	−0.0507	0.080*
H2B	0.2182	0.6029	−0.0235	0.080*
H2C	0.1676	0.5110	0.0279	0.080*
C15	1.0255 (3)	0.8246 (2)	1.13515 (19)	0.0585 (6)
H15A	0.9317	0.7778	1.1395	0.088*
H15B	1.0496	0.9179	1.1949	0.088*
H15C	1.1133	0.7955	1.1578	0.088*
C7	0.5575 (3)	0.29262 (19)	0.1735 (2)	0.0622 (6)
H7A	0.6410	0.2931	0.2361	0.093*
H7B	0.5669	0.2428	0.0886	0.093*
H7C	0.4561	0.2527	0.1736	0.093*
C8	0.4394 (3)	1.1471 (2)	0.3715 (2)	0.0615 (6)
H8A	0.3507	1.1515	0.3172	0.092*
H8B	0.5354	1.2086	0.3867	0.092*
H8C	0.4235	1.1694	0.4530	0.092*
C16	1.1183 (3)	0.6249 (2)	0.30563 (19)	0.0606 (6)
H16A	1.2061	0.6797	0.3028	0.091*
H16B	1.0215	0.6108	0.2444	0.091*
H16C	1.1354	0.5413	0.2838	0.091*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O2	0.0450 (7)	0.0421 (7)	0.0381 (7)	0.0013 (6)	0.0023 (6)	0.0150 (6)
O4	0.0481 (8)	0.0373 (7)	0.0384 (7)	0.0026 (6)	0.0046 (6)	0.0109 (6)
O3	0.0435 (8)	0.0760 (10)	0.0429 (8)	−0.0041 (7)	−0.0020 (6)	0.0335 (8)
O1	0.0390 (8)	0.0510 (8)	0.0730 (10)	−0.0083 (7)	−0.0028 (7)	0.0297 (8)
N11	0.0412 (9)	0.0335 (8)	0.0358 (8)	0.0004 (6)	0.0062 (7)	0.0142 (7)
N5	0.0354 (8)	0.0437 (9)	0.0340 (8)	0.0057 (7)	0.0019 (7)	0.0148 (7)
N8	0.0333 (8)	0.0458 (9)	0.0382 (9)	0.0007 (7)	0.0040 (7)	0.0176 (7)
N1	0.0308 (8)	0.0387 (8)	0.0433 (9)	0.0011 (6)	0.0026 (7)	0.0170 (7)
N4	0.0337 (8)	0.0375 (8)	0.0354 (8)	0.0039 (6)	0.0007 (6)	0.0139 (7)
N2	0.0311 (8)	0.0403 (9)	0.0478 (9)	0.0012 (7)	−0.0003 (7)	0.0183 (7)
N10	0.0405 (8)	0.0330 (8)	0.0312 (8)	−0.0004 (6)	0.0054 (6)	0.0114 (6)
N7	0.0351 (8)	0.0463 (9)	0.0337 (8)	0.0013 (7)	0.0041 (6)	0.0184 (7)
C5	0.0347 (9)	0.0410 (10)	0.0344 (10)	0.0026 (8)	0.0086 (8)	0.0189 (8)
C9	0.0371 (10)	0.0357 (9)	0.0355 (10)	0.0080 (8)	0.0059 (8)	0.0157 (8)
N12	0.0478 (9)	0.0414 (8)	0.0337 (8)	0.0040 (7)	0.0104 (7)	0.0130 (7)
C12	0.0356 (9)	0.0359 (9)	0.0345 (10)	0.0071 (7)	0.0074 (8)	0.0157 (8)
N3	0.0419 (9)	0.0375 (8)	0.0465 (9)	0.0002 (7)	−0.0005 (7)	0.0184 (7)
C4	0.0376 (10)	0.0399 (10)	0.0386 (10)	−0.0003 (8)	0.0084 (8)	0.0162 (8)
N6	0.0510 (10)	0.0433 (9)	0.0371 (8)	0.0113 (7)	0.0055 (7)	0.0184 (7)
N9	0.0410 (9)	0.0636 (11)	0.0379 (9)	0.0014 (8)	0.0068 (7)	0.0257 (8)
C14	0.0378 (10)	0.0345 (9)	0.0340 (9)	0.0101 (8)	0.0042 (8)	0.0158 (8)
C3	0.0355 (10)	0.0417 (10)	0.0388 (10)	0.0050 (8)	0.0065 (8)	0.0206 (8)
C13	0.0381 (10)	0.0469 (11)	0.0361 (10)	0.0085 (8)	0.0051 (8)	0.0211 (9)
C6	0.0315 (9)	0.0438 (10)	0.0340 (9)	0.0060 (8)	0.0092 (7)	0.0162 (8)
C10	0.0392 (11)	0.0532 (12)	0.0458 (11)	0.0014 (9)	0.0072 (9)	0.0170 (10)
C11	0.0526 (12)	0.0416 (10)	0.0386 (10)	−0.0013 (9)	0.0072 (9)	0.0152 (9)
C1	0.0326 (10)	0.0471 (11)	0.0675 (14)	0.0022 (9)	−0.0023 (9)	0.0262 (10)
C2	0.0467 (12)	0.0517 (12)	0.0385 (11)	0.0049 (9)	0.0006 (9)	0.0155 (9)
C15	0.0535 (13)	0.0769 (15)	0.0432 (11)	0.0097 (11)	0.0124 (10)	0.0345 (11)
C7	0.0627 (14)	0.0434 (11)	0.0638 (14)	0.0043 (10)	0.0048 (11)	0.0257 (11)
C8	0.0726 (15)	0.0491 (12)	0.0582 (13)	0.0209 (11)	0.0138 (12)	0.0271 (11)
C16	0.0711 (15)	0.0603 (13)	0.0410 (11)	0.0120 (11)	0.0205 (11)	0.0215 (10)

Geometric parameters (Å, º) top

O2—C5	1.221 (2)	N6—H6	0.8600
O4—C14	1.221 (2)	N9—C13	1.327 (2)
O3—C13	1.221 (2)	N9—C15	1.447 (2)
O1—C4	1.217 (2)	N9—H9	0.8600
N11—C12	1.280 (2)	C3—C1	1.487 (2)
N11—N10	1.4251 (19)	C6—C2	1.491 (2)
N5—C6	1.274 (2)	C10—H10A	0.9600
N5—N4	1.418 (2)	C10—H10B	0.9600
N8—C9	1.276 (2)	C10—H10C	0.9600
N8—N7	1.423 (2)	C11—H11A	0.9600
N1—C6	1.400 (2)	C11—H11B	0.9600
N1—C4	1.413 (2)	C11—H11C	0.9600
N1—N2	1.423 (2)	C1—H1A	0.9600
N4—C3	1.388 (2)	C1—H1B	0.9600
N4—C5	1.414 (2)	C1—H1C	0.9600
N2—C3	1.276 (2)	C2—H2A	0.9600
N10—C9	1.386 (2)	C2—H2B	0.9600
N10—C14	1.404 (2)	C2—H2C	0.9600
N7—C12	1.390 (2)	C15—H15A	0.9600
N7—C13	1.406 (2)	C15—H15B	0.9600
C5—N6	1.325 (2)	C15—H15C	0.9600
C9—C10	1.491 (2)	C7—H7A	0.9600
N12—C14	1.328 (2)	C7—H7B	0.9600
N12—C16	1.451 (2)	C7—H7C	0.9600
N12—H12	0.8600	C8—H8A	0.9600
C12—C11	1.489 (2)	C8—H8B	0.9600
N3—C4	1.323 (2)	C8—H8C	0.9600
N3—C7	1.445 (2)	C16—H16A	0.9600
N3—H3	0.8600	C16—H16B	0.9600
N6—C8	1.437 (3)	C16—H16C	0.9600

C12—N11—N10	114.96 (14)	N5—C6—C2	117.15 (17)
C6—N5—N4	115.19 (15)	N1—C6—C2	122.75 (16)
C9—N8—N7	115.02 (15)	C9—C10—H10A	109.5
C6—N1—C4	124.52 (15)	C9—C10—H10B	109.5
C6—N1—N2	116.29 (14)	H10A—C10—H10B	109.5
C4—N1—N2	114.69 (14)	C9—C10—H10C	109.5
C3—N4—C5	124.12 (14)	H10A—C10—H10C	109.5
C3—N4—N5	116.73 (14)	H10B—C10—H10C	109.5
C5—N4—N5	115.63 (14)	C12—C11—H11A	109.5
C3—N2—N1	114.98 (15)	C12—C11—H11B	109.5
C9—N10—C14	125.66 (14)	H11A—C11—H11B	109.5
C9—N10—N11	117.72 (13)	C12—C11—H11C	109.5
C14—N10—N11	115.71 (14)	H11A—C11—H11C	109.5
C12—N7—C13	124.70 (15)	H11B—C11—H11C	109.5
C12—N7—N8	117.36 (14)	C3—C1—H1A	109.5
C13—N7—N8	114.98 (14)	C3—C1—H1B	109.5
O2—C5—N6	124.99 (17)	H1A—C1—H1B	109.5
O2—C5—N4	120.13 (16)	C3—C1—H1C	109.5
N6—C5—N4	114.86 (15)	H1A—C1—H1C	109.5
N8—C9—N10	120.67 (16)	H1B—C1—H1C	109.5
N8—C9—C10	116.79 (17)	C6—C2—H2A	109.5
N10—C9—C10	122.46 (16)	C6—C2—H2B	109.5
C14—N12—C16	120.73 (16)	H2A—C2—H2B	109.5
C14—N12—H12	119.6	C6—C2—H2C	109.5
C16—N12—H12	119.6	H2A—C2—H2C	109.5
N11—C12—N7	120.50 (15)	H2B—C2—H2C	109.5
N11—C12—C11	117.34 (16)	N9—C15—H15A	109.5
N7—C12—C11	122.13 (15)	N9—C15—H15B	109.5
C4—N3—C7	121.39 (16)	H15A—C15—H15B	109.5
C4—N3—H3	119.3	N9—C15—H15C	109.5
C7—N3—H3	119.3	H15A—C15—H15C	109.5
O1—C4—N3	124.76 (18)	H15B—C15—H15C	109.5
O1—C4—N1	120.22 (17)	N3—C7—H7A	109.5
N3—C4—N1	114.97 (15)	N3—C7—H7B	109.5
C5—N6—C8	120.58 (16)	H7A—C7—H7B	109.5
C5—N6—H6	119.7	N3—C7—H7C	109.5
C8—N6—H6	119.7	H7A—C7—H7C	109.5
C13—N9—C15	120.93 (16)	H7B—C7—H7C	109.5
C13—N9—H9	119.5	N6—C8—H8A	109.5
C15—N9—H9	119.5	N6—C8—H8B	109.5
O4—C14—N12	124.41 (16)	H8A—C8—H8B	109.5
O4—C14—N10	120.80 (16)	N6—C8—H8C	109.5
N12—C14—N10	114.76 (15)	H8A—C8—H8C	109.5
N2—C3—N4	120.34 (16)	H8B—C8—H8C	109.5
N2—C3—C1	117.75 (17)	N12—C16—H16A	109.5
N4—C3—C1	121.85 (16)	N12—C16—H16B	109.5
O3—C13—N9	124.37 (17)	H16A—C16—H16B	109.5
O3—C13—N7	120.74 (17)	N12—C16—H16C	109.5
N9—C13—N7	114.83 (16)	H16A—C16—H16C	109.5
N5—C6—N1	120.09 (15)	H16B—C16—H16C	109.5

C6—N5—N4—C3	33.9 (2)	C6—N1—C4—N3	162.35 (16)
C6—N5—N4—C5	−166.36 (15)	N2—N1—C4—N3	7.1 (2)
C6—N1—N2—C3	33.9 (2)	O2—C5—N6—C8	−5.5 (3)
C4—N1—N2—C3	−168.75 (16)	N4—C5—N6—C8	172.64 (16)
C12—N11—N10—C9	31.0 (2)	C16—N12—C14—O4	1.3 (3)
C12—N11—N10—C14	−159.33 (16)	C16—N12—C14—N10	179.32 (17)
C9—N8—N7—C12	32.6 (2)	C9—N10—C14—O4	−8.9 (3)
C9—N8—N7—C13	−165.91 (16)	N11—N10—C14—O4	−177.71 (15)
C3—N4—C5—O2	−25.0 (3)	C9—N10—C14—N12	172.96 (16)
N5—N4—C5—O2	176.99 (15)	N11—N10—C14—N12	4.2 (2)
C3—N4—C5—N6	156.80 (16)	N1—N2—C3—N4	−4.4 (2)
N5—N4—C5—N6	−1.2 (2)	N1—N2—C3—C1	178.52 (17)
N7—N8—C9—N10	−6.1 (2)	C5—N4—C3—N2	172.45 (16)
N7—N8—C9—C10	177.08 (15)	N5—N4—C3—N2	−29.7 (2)
C14—N10—C9—N8	165.74 (17)	C5—N4—C3—C1	−10.6 (3)
N11—N10—C9—N8	−25.7 (2)	N5—N4—C3—C1	147.23 (18)
C14—N10—C9—C10	−17.6 (3)	C15—N9—C13—O3	1.0 (3)
N11—N10—C9—C10	150.96 (17)	C15—N9—C13—N7	178.38 (17)
N10—N11—C12—N7	−4.4 (2)	C12—N7—C13—O3	−19.3 (3)
N10—N11—C12—C11	177.61 (16)	N8—N7—C13—O3	−179.19 (17)
C13—N7—C12—N11	173.17 (17)	C12—N7—C13—N9	163.24 (17)
N8—N7—C12—N11	−27.3 (2)	N8—N7—C13—N9	3.3 (2)
C13—N7—C12—C11	−8.9 (3)	N4—N5—C6—N1	−4.2 (2)
N8—N7—C12—C11	150.58 (17)	N4—N5—C6—C2	176.52 (15)
C7—N3—C4—O1	4.1 (3)	C4—N1—C6—N5	175.41 (16)
C7—N3—C4—N1	−178.51 (17)	N2—N1—C6—N5	−29.7 (2)
C6—N1—C4—O1	−20.2 (3)	C4—N1—C6—C2	−5.3 (3)
N2—N1—C4—O1	−175.36 (16)	N2—N1—C6—C2	149.51 (17)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···N2	0.86	2.16	2.572 (2)	108
N6—H6···N5	0.86	2.19	2.586 (2)	108
N9—H9···N8	0.86	2.15	2.567 (2)	109
N12—H12···N11	0.86	2.17	2.581 (2)	109
N3—H3···O4	0.86	2.20	2.925 (2)	142
N6—H6···O3ⁱ	0.86	2.16	2.918 (2)	146
N9—H9···O1ⁱⁱ	0.86	2.14	2.877 (3)	143
N12—H12···O2ⁱⁱⁱ	0.86	2.24	2.967 (3)	142

Symmetry codes: (i) x−1, y, z−1; (ii) −x+1, −y+1, −z+1; (iii) −x+2, −y+2, −z+1.

Experimental details

Crystal data
Chemical formula	C₈H₁₄N₆O₂
M_r	226.25
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	9.0002 (17), 12.045 (2), 12.357 (2)
α, β, γ (°)	118.386 (2), 101.701 (3), 99.494 (3)
V (Å³)	1099.6 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.34 × 0.30 × 0.15

Data collection
Diffractometer	Bruker SMART CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 1997)
T_min, T_max	0.966, 0.985
No. of measured, independent and observed [I > 2σ(I)] reflections	5571, 3809, 3178
R_int	0.018
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.044, 0.115, 1.06
No. of reflections	3809
No. of parameters	298
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.17, −0.19

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···N2	0.86	2.16	2.572 (2)	108
N6—H6···N5	0.86	2.19	2.586 (2)	108
N9—H9···N8	0.86	2.15	2.567 (2)	109
N12—H12···N11	0.86	2.17	2.581 (2)	109
N3—H3···O4	0.86	2.20	2.925 (2)	142
N6—H6···O3ⁱ	0.86	2.16	2.918 (2)	146
N9—H9···O1ⁱⁱ	0.86	2.14	2.877 (3)	143
N12—H12···O2ⁱⁱⁱ	0.86	2.24	2.967 (3)	142

Symmetry codes: (i) x−1, y, z−1; (ii) −x+1, −y+1, −z+1; (iii) −x+2, −y+2, −z+1.

Acknowledgements

The authors are very grateful to the Natural Science Foundation of Zhejiang Province (No. Y2090985) and the National Natural Science Foundation of China (No. 20802069) for financial support.

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