3,6-Dimethyl-N,N-bis-(pyridin-2-yl)-1,2,4,5-tetra-zine-1,4-dicarboxamide.

In the title mol-ecule, C(16)H(16)N(8)O(2), four atoms of the tetra-zine ring are coplanar, with the largest deviation from the plane being 0.0236 (12) Å; the other two atoms of the tetra-zine ring deviate on the same side from this plane by 0.320 (4) and 0.335 (4) Å. Therefore, the central tetra-zine ring exhibits a boat conformation. The dihedral angles between the mean plane of the four coplanar atoms of the tetrazine ring and the two pyridine rings are 26.22 (10) and 6.97 (5)°. The two pyridine rings form a dihedral angle of 31.27 (8)°. In the molecule, there are a number of short C-H⋯O interactions. In the crystal, molecules are linked via a C-H⋯O interaction to form zigzag chains propagating along the [010] direction.

Related literature

For the activities of 1,2,4,5-tetra­zine derivatives in chemical reactions, see: Domingo et al. (2009 ▶); Lorincz et al. (2010 ▶). For biological activities in 1,2,4,5-tetra­zine derivatives, see: Eremeev et al. (1978 ▶, 1980 ▶); Neunhoeffer (1984 ▶); Sauer (1996 ▶). For anti­tumor activities of 1,2,4,5-tetra­zine derivatives, see: Hu et al. (2002 ▶, 2004 ▶); Rao & Hu (2005 ▶, 2006 ▶). For typical bond lengths for C=N double and C—N and N—N single bonds, see: Allen et al. (1987 ▶). For the synthesis of the title compound, see: Hu et al. (2004 ▶); Skorianetz & Kováts (1970 ▶, 1971 ▶); Sun et al. (2003 ▶).

Experimental

Crystal data

C16H16N8O2

M = 352.37

Monoclinic,

a = 11.753 (2) Å

b = 20.081 (4) Å

c = 7.2012 (14) Å

β = 96.273 (3)°

V = 1689.4 (6) Å3

Z = 4

Mo Kα radiation

μ = 0.10 mm−1

T = 298 K

0.36 × 0.23 × 0.20 mm

Data collection

Bruker SMART CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 1997 ▶) T min = 0.965, T max = 0.981

7032 measured reflections

2985 independent reflections

2430 reflections with I > 2σ(I)

R int = 0.024

Refinement

R[F 2 > 2σ(F 2)] = 0.061

wR(F 2) = 0.182

S = 1.07

2985 reflections

236 parameters

H-atom parameters constrained

Δρmax = 0.44 e Å−3

Δρmin = −0.33 e Å−3

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 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812005405/zj2056sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812005405/zj2056Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536812005405/zj2056Isup3.cdx

Supplementary material file. DOI: 10.1107/S1600536812005405/zj2056Isup4.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C16H16N8O2	Z = 4
Mr = 352.37	F(000) = 736
Monoclinic, P21/c	Dx = 1.385 Mg m−3
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 11.753 (2) Å	θ = 3.0–28.2°
b = 20.081 (4) Å	µ = 0.10 mm−1
c = 7.2012 (14) Å	T = 298 K
β = 96.273 (3)°	Block, colourless
V = 1689.4 (6) Å3	0.36 × 0.23 × 0.20 mm

Bruker SMART CCD area-detector diffractometer	2985 independent reflections
Radiation source: fine-focus sealed tube	2430 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
φ and ω scans	θmax = 25.0°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Bruker, 1997)	h = −13→11
Tmin = 0.965, Tmax = 0.981	k = −23→22
7032 measured reflections	l = −8→8

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)] = 0.061	H-atom parameters constrained
wR(F2) = 0.182	w = 1/[σ2(Fo2) + (0.0986P)2 + 0.7423P] where P = (Fo2 + 2Fc2)/3
S = 1.07	(Δ/σ)max < 0.001
2985 reflections	Δρmax = 0.44 e Å−3
236 parameters	Δρmin = −0.33 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: 0.012 (2)

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.

	x	y	z	Uiso*/Ueq
N1	0.70522 (17)	0.06533 (10)	0.3165 (3)	0.0460 (5)
O2	0.94498 (16)	0.25045 (9)	0.2447 (3)	0.0587 (6)
O1	0.54879 (15)	0.00173 (9)	0.2281 (3)	0.0618 (6)
N4	0.80771 (16)	0.17897 (10)	0.3261 (3)	0.0464 (5)
N5	0.69810 (17)	0.17708 (10)	0.3912 (3)	0.0481 (6)
N2	0.82657 (17)	0.06420 (10)	0.3487 (3)	0.0480 (6)
N6	0.78462 (18)	0.29223 (10)	0.3540 (3)	0.0489 (6)
H6	0.7217	0.2801	0.3948	0.059*
N8	0.70889 (18)	0.39638 (11)	0.3514 (3)	0.0529 (6)
C12	0.8038 (2)	0.36064 (12)	0.3445 (3)	0.0434 (6)
C3	0.8743 (2)	0.12142 (12)	0.3484 (4)	0.0448 (6)
N7	0.7973 (2)	−0.14331 (12)	0.1576 (4)	0.0649 (7)
N3	0.72486 (18)	−0.04631 (10)	0.2546 (3)	0.0532 (6)
H3	0.7933	−0.0403	0.3073	0.064*
C6	0.6486 (2)	0.12036 (12)	0.3784 (3)	0.0432 (6)
C4	0.6513 (2)	0.00504 (12)	0.2642 (4)	0.0449 (6)
C5	0.8541 (2)	0.24270 (12)	0.3062 (4)	0.0453 (6)
C7	0.7024 (2)	−0.10818 (12)	0.1687 (4)	0.0470 (6)
C2	0.5324 (2)	0.11538 (14)	0.4433 (4)	0.0570 (7)
H2A	0.5046	0.0706	0.4263	0.086*
H2B	0.4811	0.1453	0.3721	0.086*
H2C	0.5369	0.1270	0.5733	0.086*
C13	0.9103 (2)	0.38885 (13)	0.3336 (4)	0.0503 (7)
H13	0.9753	0.3625	0.3325	0.060*
C8	0.5943 (2)	−0.13104 (13)	0.1018 (4)	0.0538 (7)
H8	0.5294	−0.1055	0.1130	0.065*
C16	0.7187 (2)	0.46207 (14)	0.3430 (4)	0.0585 (8)
H16	0.6530	0.4876	0.3476	0.070*
C9	0.5865 (3)	−0.19228 (15)	0.0190 (4)	0.0637 (8)
H9	0.5153	−0.2090	−0.0276	0.076*
C14	0.9165 (2)	0.45670 (14)	0.3243 (5)	0.0590 (8)
H14	0.9866	0.4773	0.3156	0.071*
C1	1.0012 (2)	0.12417 (14)	0.3833 (5)	0.0599 (8)
H1A	1.0262	0.1696	0.3778	0.090*
H1B	1.0340	0.0985	0.2900	0.090*
H1C	1.0255	0.1062	0.5047	0.090*
C15	0.8196 (2)	0.49461 (14)	0.3279 (4)	0.0617 (8)
H15	0.8225	0.5408	0.3204	0.074*
C11	0.7852 (3)	−0.20271 (15)	0.0760 (6)	0.0745 (10)
H11	0.8509	−0.2278	0.0673	0.089*
C10	0.6832 (3)	−0.22915 (15)	0.0042 (5)	0.0677 (9)
H10	0.6792	−0.2708	−0.0528	0.081*

	U11	U22	U33	U12	U13	U23
N1	0.0367 (11)	0.0442 (12)	0.0563 (13)	−0.0043 (8)	0.0015 (9)	−0.0017 (9)
O2	0.0514 (11)	0.0516 (11)	0.0763 (14)	−0.0098 (8)	0.0211 (10)	−0.0047 (9)
O1	0.0400 (11)	0.0556 (12)	0.0884 (15)	−0.0066 (8)	0.0015 (10)	−0.0091 (10)
N4	0.0383 (11)	0.0449 (12)	0.0569 (13)	−0.0051 (9)	0.0096 (9)	−0.0016 (9)
N5	0.0416 (12)	0.0473 (12)	0.0564 (13)	−0.0014 (9)	0.0106 (10)	0.0033 (10)
N2	0.0385 (11)	0.0458 (12)	0.0589 (14)	−0.0031 (9)	0.0014 (9)	−0.0054 (10)
N6	0.0411 (11)	0.0452 (12)	0.0612 (14)	−0.0053 (9)	0.0091 (10)	0.0018 (10)
N8	0.0386 (12)	0.0528 (13)	0.0662 (15)	−0.0012 (9)	0.0005 (10)	−0.0054 (11)
C12	0.0392 (13)	0.0466 (14)	0.0435 (14)	−0.0031 (10)	−0.0001 (10)	−0.0015 (10)
C3	0.0423 (13)	0.0445 (14)	0.0476 (14)	−0.0025 (10)	0.0042 (11)	−0.0062 (11)
N7	0.0469 (14)	0.0496 (13)	0.097 (2)	−0.0010 (10)	0.0032 (13)	−0.0065 (13)
N3	0.0397 (12)	0.0461 (12)	0.0713 (16)	−0.0053 (9)	−0.0047 (10)	−0.0034 (11)
C6	0.0417 (13)	0.0430 (13)	0.0446 (14)	−0.0024 (10)	0.0037 (10)	0.0049 (10)
C4	0.0391 (14)	0.0456 (14)	0.0498 (15)	−0.0056 (10)	0.0033 (11)	0.0033 (11)
C5	0.0424 (14)	0.0458 (14)	0.0475 (14)	−0.0053 (11)	0.0048 (11)	−0.0032 (11)
C7	0.0438 (14)	0.0422 (14)	0.0546 (16)	−0.0047 (11)	0.0029 (11)	0.0049 (11)
C2	0.0475 (15)	0.0543 (16)	0.0718 (19)	−0.0021 (12)	0.0180 (13)	0.0038 (13)
C13	0.0383 (13)	0.0482 (15)	0.0634 (17)	−0.0017 (11)	0.0012 (12)	−0.0047 (12)
C8	0.0452 (15)	0.0504 (15)	0.0643 (18)	−0.0017 (11)	−0.0011 (13)	−0.0011 (13)
C16	0.0480 (15)	0.0530 (16)	0.074 (2)	0.0060 (12)	0.0023 (13)	−0.0084 (14)
C9	0.0574 (17)	0.0631 (18)	0.068 (2)	−0.0102 (14)	−0.0051 (14)	−0.0099 (15)
C14	0.0464 (15)	0.0530 (16)	0.079 (2)	−0.0108 (12)	0.0120 (14)	−0.0075 (14)
C1	0.0422 (15)	0.0531 (16)	0.083 (2)	−0.0020 (12)	0.0027 (14)	−0.0067 (14)
C15	0.0600 (18)	0.0449 (15)	0.081 (2)	−0.0065 (13)	0.0130 (15)	−0.0078 (14)
C11	0.0591 (19)	0.0521 (17)	0.113 (3)	0.0049 (14)	0.0123 (18)	−0.0106 (17)
C10	0.070 (2)	0.0518 (17)	0.081 (2)	−0.0028 (15)	0.0032 (16)	−0.0148 (15)

N1—C6	1.388 (3)	C6—C2	1.494 (3)
N1—C4	1.399 (3)	C7—C8	1.387 (4)
N1—N2	1.420 (3)	C2—H2A	0.9600
O2—C5	1.210 (3)	C2—H2B	0.9600
O1—C4	1.206 (3)	C2—H2C	0.9600
N4—C3	1.395 (3)	C13—C14	1.367 (4)
N4—C5	1.405 (3)	C13—H13	0.9300
N4—N5	1.419 (3)	C8—C9	1.366 (4)
N5—C6	1.278 (3)	C8—H8	0.9300
N2—C3	1.279 (3)	C16—C15	1.369 (4)
N6—C5	1.356 (3)	C16—H16	0.9300
N6—C12	1.395 (3)	C9—C10	1.370 (4)
N6—H6	0.8600	C9—H9	0.9300
N8—C16	1.326 (4)	C14—C15	1.372 (4)
N8—C12	1.332 (3)	C14—H14	0.9300
C12—C13	1.384 (3)	C1—H1A	0.9600
C3—C1	1.487 (3)	C1—H1B	0.9600
N7—C7	1.329 (3)	C1—H1C	0.9600
N7—C11	1.331 (4)	C15—H15	0.9300
N3—C4	1.353 (3)	C11—C10	1.360 (4)
N3—C7	1.400 (3)	C11—H11	0.9300
N3—H3	0.8600	C10—H10	0.9300
C6—N1—C4	123.8 (2)	C6—C2—H2B	109.5
C6—N1—N2	117.91 (19)	H2A—C2—H2B	109.5
C4—N1—N2	116.61 (19)	C6—C2—H2C	109.5
C3—N4—C5	123.2 (2)	H2A—C2—H2C	109.5
C3—N4—N5	117.25 (19)	H2B—C2—H2C	109.5
C5—N4—N5	115.78 (19)	C14—C13—C12	117.7 (2)
C6—N5—N4	115.0 (2)	C14—C13—H13	121.2
C3—N2—N1	114.7 (2)	C12—C13—H13	121.2
C5—N6—C12	127.2 (2)	C9—C8—C7	117.7 (3)
C5—N6—H6	116.4	C9—C8—H8	121.1
C12—N6—H6	116.4	C7—C8—H8	121.1
C16—N8—C12	117.2 (2)	N8—C16—C15	124.0 (3)
N8—C12—C13	123.2 (2)	N8—C16—H16	118.0
N8—C12—N6	112.9 (2)	C15—C16—H16	118.0
C13—C12—N6	123.9 (2)	C8—C9—C10	120.2 (3)
N2—C3—N4	120.3 (2)	C8—C9—H9	119.9
N2—C3—C1	117.7 (2)	C10—C9—H9	119.9
N4—C3—C1	121.9 (2)	C13—C14—C15	120.2 (3)
C7—N7—C11	116.9 (2)	C13—C14—H14	119.9
C4—N3—C7	127.5 (2)	C15—C14—H14	119.9
C4—N3—H3	116.2	C3—C1—H1A	109.5
C7—N3—H3	116.2	C3—C1—H1B	109.5
N5—C6—N1	120.2 (2)	H1A—C1—H1B	109.5
N5—C6—C2	117.5 (2)	C3—C1—H1C	109.5
N1—C6—C2	122.3 (2)	H1A—C1—H1C	109.5
O1—C4—N3	125.2 (2)	H1B—C1—H1C	109.5
O1—C4—N1	121.2 (2)	C16—C15—C14	117.7 (3)
N3—C4—N1	113.6 (2)	C16—C15—H15	121.2
O2—C5—N6	125.4 (2)	C14—C15—H15	121.2
O2—C5—N4	121.5 (2)	N7—C11—C10	124.4 (3)
N6—C5—N4	113.0 (2)	N7—C11—H11	117.8
N7—C7—C8	123.1 (3)	C10—C11—H11	117.8
N7—C7—N3	112.3 (2)	C11—C10—C9	117.6 (3)
C8—C7—N3	124.6 (2)	C11—C10—H10	121.2
C6—C2—H2A	109.5	C9—C10—H10	121.2
C3—N4—N5—C6	−32.6 (3)	C6—N1—C4—N3	−164.0 (2)
C5—N4—N5—C6	168.6 (2)	N2—N1—C4—N3	0.8 (3)
C6—N1—N2—C3	−31.4 (3)	C12—N6—C5—O2	−0.8 (4)
C4—N1—N2—C3	162.8 (2)	C12—N6—C5—N4	−177.8 (2)
C16—N8—C12—C13	1.6 (4)	C3—N4—C5—O2	25.5 (4)
C16—N8—C12—N6	−179.9 (2)	N5—N4—C5—O2	−177.0 (2)
C5—N6—C12—N8	162.7 (2)	C3—N4—C5—N6	−157.3 (2)
C5—N6—C12—C13	−18.8 (4)	N5—N4—C5—N6	0.1 (3)
N1—N2—C3—N4	2.8 (3)	C11—N7—C7—C8	0.7 (5)
N1—N2—C3—C1	179.3 (2)	C11—N7—C7—N3	−179.2 (3)
C5—N4—C3—N2	−173.6 (2)	C4—N3—C7—N7	169.7 (3)
N5—N4—C3—N2	29.3 (3)	C4—N3—C7—C8	−10.2 (4)
C5—N4—C3—C1	10.0 (4)	N8—C12—C13—C14	−1.9 (4)
N5—N4—C3—C1	−147.1 (3)	N6—C12—C13—C14	179.8 (3)
N4—N5—C6—N1	4.2 (3)	N7—C7—C8—C9	−0.8 (4)
N4—N5—C6—C2	−179.5 (2)	N3—C7—C8—C9	179.1 (3)
C4—N1—C6—N5	−167.2 (2)	C12—N8—C16—C15	−0.1 (4)
N2—N1—C6—N5	28.1 (3)	C7—C8—C9—C10	0.1 (5)
C4—N1—C6—C2	16.6 (4)	C12—C13—C14—C15	0.7 (4)
N2—N1—C6—C2	−148.0 (2)	N8—C16—C15—C14	−1.0 (5)
C7—N3—C4—O1	13.6 (5)	C13—C14—C15—C16	0.7 (5)
C7—N3—C4—N1	−164.6 (2)	C7—N7—C11—C10	0.1 (5)
C6—N1—C4—O1	17.6 (4)	N7—C11—C10—C9	−0.7 (6)
N2—N1—C4—O1	−177.6 (2)	C8—C9—C10—C11	0.6 (5)

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···O2	0.96	2.07	2.778 (4)	130
C2—H2A···O1	0.96	2.09	2.777 (4)	127
C8—H8···O1	0.93	2.31	2.886 (3)	120
C16—H16···O1i	0.93	2.39	3.229 (3)	150

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯O2	0.96	2.07	2.778 (4)	130
C2—H2A⋯O1	0.96	2.09	2.777 (4)	127
C8—H8⋯O1	0.93	2.31	2.886 (3)	120
C16—H16⋯O1i	0.93	2.39	3.229 (3)	150

Symmetry code: (i) .