organic compounds
4-[2-(Benzylsulfanyl)acetyl]-3,4-dihydroquinoxalin-2(1H)-one
aInstitute of Chemistry, University of the Punjab, Lahore, Pakistan, and bDepartment of Chemistry, GC University, Lahore 54000, Pakistan
*Correspondence e-mail: munawaralimunawar@yahoo.com
In the title compound, C17H16N2O2S, the pyrazinone ring is non-planar (r.m.s. deviation = 0.1595 Å), with maximum deviations for the 4-position N atom and the adjacent non-fused-ring C atom of 0.2557 (15) and −0.2118 (16) Å, respectively. The dihedral angle between the benzyl ring and pyrazinone rings is 30.45 (18)°. Intermolecular N—H⋯O hydrogen-bonding interactions forms inversion dimers which lead to eight-membered R22(8) ring motifs. The dimers are further connected by C—H⋯O interactions.
Related literature
For the biological activity of quinoxalines, see: Ali et al. (2000); Moustafa & Yameda (2001). For related structures see: Nasir et al. (2009). For graph-set notation, see: Bernstein et al. (1995).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2007); cell SAINT (Bruker, 2007); 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) and PLATON.
Supporting information
10.1107/S1600536811008178/hg2799sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536811008178/hg2799Isup2.hkl
To a suspension of 4-(chloroacetyl)-3,4-dihydroquinoxalin-2(1H)-2-one (2.0 g, 8.9 mmoles) in absolute ethanol (60 mL) fine powdered sodium bicarbonate (1.5 g, 17.8 mmole) was added along with phenylmethanethiol (1.1 mL, 9.0 mmoles). The reaction mixture was heated under reflux for 8-10 h, the progress of the reaction was monitored by TLC (chloroform:ethyl acetate, 7:3 v/v). The reaction mixture was concentrated to half of the original volume under reduced pressure and the precipitate of the product which formed on cooling was filtered, washed with cold ethanol and recrystallized in ethanol.
All the C—H and N—H H-atoms were positioned with idealized geometry with C—H = 0.93 Å for aromatic, with C—H = 0.97 Å for methylene and with N—H = 0.85 (3)Å for amido NH and were refined using a riding model with Uiso(H) = 1.2 Ueq(C & N). The reflection 1 1 0, 1 3 0 and 0 2 0 were omitted in final
as these were obscured by the beam stop.Data collection: APEX2 (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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) and PLATON (Spek, 2009).C17H16N2O2S | F(000) = 1312 |
Mr = 312.38 | Dx = 1.322 Mg m−3 |
Orthorhombic, Pccn | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ab 2ac | Cell parameters from 2915 reflections |
a = 13.9502 (8) Å | θ = 3.2–23.1° |
b = 32.2588 (17) Å | µ = 0.22 mm−1 |
c = 6.9728 (3) Å | T = 296 K |
V = 3137.9 (3) Å3 | Plate, colorless |
Z = 8 | 0.47 × 0.23 × 0.07 mm |
Bruker Kappa APEXII CCD diffractometer | 3892 independent reflections |
Radiation source: fine-focus sealed tube | 2412 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.044 |
ϕ and ω scans | θmax = 28.3°, θmin = 1.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2007) | h = −18→17 |
Tmin = 0.906, Tmax = 0.985 | k = −23→43 |
16363 measured reflections | l = −9→9 |
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)] = 0.055 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.183 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | w = 1/[σ2(Fo2) + (0.108P)2 + 0.1052P] where P = (Fo2 + 2Fc2)/3 |
3889 reflections | (Δ/σ)max = 0.001 |
203 parameters | Δρmax = 0.27 e Å−3 |
0 restraints | Δρmin = −0.20 e Å−3 |
C17H16N2O2S | V = 3137.9 (3) Å3 |
Mr = 312.38 | Z = 8 |
Orthorhombic, Pccn | Mo Kα radiation |
a = 13.9502 (8) Å | µ = 0.22 mm−1 |
b = 32.2588 (17) Å | T = 296 K |
c = 6.9728 (3) Å | 0.47 × 0.23 × 0.07 mm |
Bruker Kappa APEXII CCD diffractometer | 3892 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2007) | 2412 reflections with I > 2σ(I) |
Tmin = 0.906, Tmax = 0.985 | Rint = 0.044 |
16363 measured reflections |
R[F2 > 2σ(F2)] = 0.055 | 0 restraints |
wR(F2) = 0.183 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | Δρmax = 0.27 e Å−3 |
3889 reflections | Δρmin = −0.20 e Å−3 |
203 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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 | ||
S1 | 0.67947 (5) | 0.701430 (18) | 0.13947 (11) | 0.0539 (3) | |
O4 | 0.77529 (11) | 0.61610 (5) | 0.1173 (2) | 0.0439 (4) | |
N1 | 0.63517 (13) | 0.58234 (5) | 0.0968 (3) | 0.0364 (4) | |
O3 | 0.63199 (12) | 0.50899 (5) | 0.4824 (2) | 0.0530 (5) | |
C1 | 0.47960 (15) | 0.55216 (6) | 0.1309 (3) | 0.0377 (5) | |
C9 | 0.69061 (15) | 0.61743 (6) | 0.0743 (3) | 0.0331 (5) | |
C8 | 0.60499 (16) | 0.52927 (7) | 0.3446 (3) | 0.0399 (5) | |
C7 | 0.67595 (15) | 0.54813 (7) | 0.2064 (3) | 0.0400 (5) | |
H7A | 0.7311 | 0.5581 | 0.2775 | 0.048* | |
H7B | 0.6980 | 0.5269 | 0.1184 | 0.048* | |
N2 | 0.51165 (14) | 0.53532 (6) | 0.3046 (3) | 0.0442 (5) | |
C10 | 0.64388 (16) | 0.65674 (7) | 0.0037 (3) | 0.0394 (5) | |
H10A | 0.5748 | 0.6537 | 0.0112 | 0.047* | |
H10B | 0.6607 | 0.6610 | −0.1299 | 0.047* | |
C5 | 0.51272 (19) | 0.58963 (8) | −0.1586 (4) | 0.0490 (6) | |
H5 | 0.5557 | 0.6032 | −0.2391 | 0.059* | |
C12 | 0.50134 (19) | 0.69134 (8) | 0.3071 (4) | 0.0514 (6) | |
C6 | 0.54236 (15) | 0.57563 (6) | 0.0199 (3) | 0.0364 (5) | |
C3 | 0.35632 (19) | 0.56161 (9) | −0.1015 (4) | 0.0581 (7) | |
H3 | 0.2931 | 0.5579 | −0.1402 | 0.070* | |
C2 | 0.38689 (17) | 0.54535 (7) | 0.0697 (4) | 0.0477 (6) | |
H2 | 0.3451 | 0.5297 | 0.1445 | 0.057* | |
C11 | 0.6058 (2) | 0.69568 (9) | 0.3512 (4) | 0.0577 (7) | |
H11A | 0.6269 | 0.6714 | 0.4217 | 0.069* | |
H11B | 0.6150 | 0.7197 | 0.4332 | 0.069* | |
C4 | 0.4191 (2) | 0.58341 (8) | −0.2165 (4) | 0.0592 (7) | |
H4 | 0.3983 | 0.5940 | −0.3334 | 0.071* | |
C13 | 0.4534 (3) | 0.65588 (11) | 0.3446 (5) | 0.0776 (9) | |
H13 | 0.4853 | 0.6339 | 0.4025 | 0.093* | |
C16 | 0.3583 (3) | 0.7183 (2) | 0.1691 (9) | 0.156 (3) | |
H16 | 0.3267 | 0.7396 | 0.1054 | 0.188* | |
C14 | 0.3569 (3) | 0.65185 (15) | 0.2976 (7) | 0.1123 (16) | |
H14 | 0.3240 | 0.6275 | 0.3254 | 0.135* | |
C17 | 0.4533 (2) | 0.72278 (13) | 0.2194 (7) | 0.1095 (15) | |
H17 | 0.4849 | 0.7475 | 0.1932 | 0.131* | |
C15 | 0.3119 (3) | 0.6836 (2) | 0.2115 (7) | 0.133 (2) | |
H15 | 0.2473 | 0.6812 | 0.1811 | 0.160* | |
H1N | 0.471 (2) | 0.5207 (9) | 0.367 (4) | 0.060 (8)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0418 (4) | 0.0307 (3) | 0.0892 (6) | −0.0038 (2) | 0.0018 (3) | −0.0011 (3) |
O4 | 0.0330 (9) | 0.0376 (8) | 0.0611 (10) | −0.0068 (7) | −0.0027 (7) | 0.0045 (7) |
N1 | 0.0310 (10) | 0.0358 (10) | 0.0424 (10) | −0.0056 (8) | −0.0005 (8) | 0.0066 (8) |
O3 | 0.0451 (10) | 0.0577 (11) | 0.0561 (11) | −0.0119 (8) | −0.0068 (8) | 0.0193 (9) |
C1 | 0.0321 (11) | 0.0339 (11) | 0.0473 (13) | −0.0016 (9) | 0.0012 (10) | 0.0006 (10) |
C9 | 0.0322 (11) | 0.0316 (10) | 0.0356 (11) | −0.0031 (9) | 0.0043 (9) | −0.0004 (9) |
C8 | 0.0380 (12) | 0.0360 (11) | 0.0456 (13) | −0.0075 (10) | 0.0005 (10) | 0.0048 (10) |
C7 | 0.0315 (11) | 0.0358 (11) | 0.0527 (13) | −0.0028 (9) | 0.0015 (10) | 0.0092 (10) |
N2 | 0.0336 (11) | 0.0494 (11) | 0.0495 (12) | −0.0061 (9) | 0.0057 (9) | 0.0140 (10) |
C10 | 0.0355 (12) | 0.0381 (12) | 0.0447 (12) | −0.0009 (10) | 0.0063 (10) | 0.0042 (10) |
C5 | 0.0462 (15) | 0.0544 (15) | 0.0464 (14) | −0.0109 (12) | −0.0015 (11) | 0.0093 (11) |
C12 | 0.0476 (15) | 0.0572 (15) | 0.0495 (14) | 0.0108 (12) | 0.0027 (11) | −0.0060 (12) |
C6 | 0.0302 (11) | 0.0332 (10) | 0.0459 (12) | −0.0037 (9) | −0.0009 (9) | −0.0002 (9) |
C3 | 0.0391 (13) | 0.0587 (16) | 0.0765 (19) | −0.0109 (13) | −0.0155 (13) | −0.0009 (14) |
C2 | 0.0338 (12) | 0.0452 (13) | 0.0642 (16) | −0.0086 (11) | 0.0019 (11) | 0.0022 (12) |
C11 | 0.0540 (17) | 0.0592 (16) | 0.0599 (16) | 0.0099 (13) | −0.0070 (13) | −0.0154 (13) |
C4 | 0.0557 (17) | 0.0663 (17) | 0.0558 (16) | −0.0097 (14) | −0.0181 (13) | 0.0063 (13) |
C13 | 0.068 (2) | 0.075 (2) | 0.090 (2) | −0.0013 (18) | 0.0167 (18) | −0.0014 (18) |
C16 | 0.062 (3) | 0.211 (6) | 0.197 (6) | 0.044 (3) | 0.011 (3) | 0.093 (5) |
C14 | 0.076 (3) | 0.135 (4) | 0.126 (4) | −0.044 (3) | 0.031 (3) | −0.041 (3) |
C17 | 0.053 (2) | 0.099 (3) | 0.176 (4) | 0.028 (2) | 0.007 (2) | 0.054 (3) |
C15 | 0.050 (2) | 0.241 (7) | 0.109 (4) | 0.011 (3) | −0.010 (2) | −0.007 (4) |
S1—C10 | 1.795 (2) | C5—H5 | 0.9300 |
S1—C11 | 1.808 (3) | C12—C13 | 1.351 (4) |
O4—C9 | 1.219 (3) | C12—C17 | 1.361 (4) |
N1—C9 | 1.380 (3) | C12—C11 | 1.496 (4) |
N1—C6 | 1.418 (3) | C3—C2 | 1.372 (4) |
N1—C7 | 1.458 (3) | C3—C4 | 1.380 (4) |
O3—C8 | 1.222 (3) | C3—H3 | 0.9300 |
C1—C2 | 1.380 (3) | C2—H2 | 0.9300 |
C1—C6 | 1.393 (3) | C11—H11A | 0.9700 |
C1—N2 | 1.400 (3) | C11—H11B | 0.9700 |
C9—C10 | 1.508 (3) | C4—H4 | 0.9300 |
C8—N2 | 1.346 (3) | C13—C14 | 1.392 (5) |
C8—C7 | 1.509 (3) | C13—H13 | 0.9300 |
C7—H7A | 0.9700 | C16—C15 | 1.327 (8) |
C7—H7B | 0.9700 | C16—C17 | 1.379 (6) |
N2—H1N | 0.85 (3) | C16—H16 | 0.9300 |
C10—H10A | 0.9700 | C14—C15 | 1.342 (7) |
C10—H10B | 0.9700 | C14—H14 | 0.9300 |
C5—C4 | 1.382 (4) | C17—H17 | 0.9300 |
C5—C6 | 1.387 (3) | C15—H15 | 0.9300 |
C10—S1—C11 | 101.02 (12) | C5—C6—C1 | 119.2 (2) |
C9—N1—C6 | 126.45 (18) | C5—C6—N1 | 124.2 (2) |
C9—N1—C7 | 117.51 (17) | C1—C6—N1 | 116.55 (19) |
C6—N1—C7 | 116.03 (17) | C2—C3—C4 | 120.2 (2) |
C2—C1—C6 | 120.3 (2) | C2—C3—H3 | 119.9 |
C2—C1—N2 | 120.3 (2) | C4—C3—H3 | 119.9 |
C6—C1—N2 | 119.4 (2) | C3—C2—C1 | 120.0 (2) |
O4—C9—N1 | 119.08 (19) | C3—C2—H2 | 120.0 |
O4—C9—C10 | 121.91 (19) | C1—C2—H2 | 120.0 |
N1—C9—C10 | 118.98 (19) | C12—C11—S1 | 113.29 (19) |
O3—C8—N2 | 122.6 (2) | C12—C11—H11A | 108.9 |
O3—C8—C7 | 121.0 (2) | S1—C11—H11A | 108.9 |
N2—C8—C7 | 116.3 (2) | C12—C11—H11B | 108.9 |
N1—C7—C8 | 112.57 (18) | S1—C11—H11B | 108.9 |
N1—C7—H7A | 109.1 | H11A—C11—H11B | 107.7 |
C8—C7—H7A | 109.1 | C3—C4—C5 | 120.3 (3) |
N1—C7—H7B | 109.1 | C3—C4—H4 | 119.9 |
C8—C7—H7B | 109.1 | C5—C4—H4 | 119.9 |
H7A—C7—H7B | 107.8 | C12—C13—C14 | 120.8 (4) |
C8—N2—C1 | 123.0 (2) | C12—C13—H13 | 119.6 |
C8—N2—H1N | 117.0 (19) | C14—C13—H13 | 119.6 |
C1—N2—H1N | 116.3 (19) | C15—C16—C17 | 120.0 (5) |
C9—C10—S1 | 112.54 (16) | C15—C16—H16 | 120.0 |
C9—C10—H10A | 109.1 | C17—C16—H16 | 120.0 |
S1—C10—H10A | 109.1 | C15—C14—C13 | 119.1 (4) |
C9—C10—H10B | 109.1 | C15—C14—H14 | 120.4 |
S1—C10—H10B | 109.1 | C13—C14—H14 | 120.4 |
H10A—C10—H10B | 107.8 | C12—C17—C16 | 120.7 (4) |
C4—C5—C6 | 119.8 (2) | C12—C17—H17 | 119.7 |
C4—C5—H5 | 120.1 | C16—C17—H17 | 119.7 |
C6—C5—H5 | 120.1 | C16—C15—C14 | 121.1 (4) |
C13—C12—C17 | 118.3 (3) | C16—C15—H15 | 119.5 |
C13—C12—C11 | 121.4 (3) | C14—C15—H15 | 119.5 |
C17—C12—C11 | 120.2 (3) | ||
C6—N1—C9—O4 | −166.4 (2) | C9—N1—C6—C5 | 36.4 (3) |
C7—N1—C9—O4 | 12.1 (3) | C7—N1—C6—C5 | −142.1 (2) |
C6—N1—C9—C10 | 15.7 (3) | C9—N1—C6—C1 | −145.9 (2) |
C7—N1—C9—C10 | −165.86 (19) | C7—N1—C6—C1 | 35.6 (3) |
C9—N1—C7—C8 | 136.4 (2) | C4—C3—C2—C1 | 2.5 (4) |
C6—N1—C7—C8 | −44.9 (3) | C6—C1—C2—C3 | 0.2 (4) |
O3—C8—C7—N1 | −159.2 (2) | N2—C1—C2—C3 | −179.4 (2) |
N2—C8—C7—N1 | 22.2 (3) | C13—C12—C11—S1 | 114.1 (3) |
O3—C8—N2—C1 | −168.6 (2) | C17—C12—C11—S1 | −62.9 (4) |
C7—C8—N2—C1 | 10.0 (3) | C10—S1—C11—C12 | −54.1 (2) |
C2—C1—N2—C8 | 158.4 (2) | C2—C3—C4—C5 | −1.1 (4) |
C6—C1—N2—C8 | −21.2 (3) | C6—C5—C4—C3 | −3.1 (4) |
O4—C9—C10—S1 | −43.2 (3) | C17—C12—C13—C14 | −1.1 (5) |
N1—C9—C10—S1 | 134.71 (18) | C11—C12—C13—C14 | −178.1 (3) |
C11—S1—C10—C9 | −78.50 (18) | C12—C13—C14—C15 | 1.0 (6) |
C4—C5—C6—C1 | 5.8 (4) | C13—C12—C17—C16 | −0.4 (6) |
C4—C5—C6—N1 | −176.6 (2) | C11—C12—C17—C16 | 176.6 (4) |
C2—C1—C6—C5 | −4.4 (3) | C15—C16—C17—C12 | 2.1 (9) |
N2—C1—C6—C5 | 175.2 (2) | C17—C16—C15—C14 | −2.3 (10) |
C2—C1—C6—N1 | 177.8 (2) | C13—C14—C15—C16 | 0.7 (8) |
N2—C1—C6—N1 | −2.6 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C5—H5···O4i | 0.93 | 2.60 | 3.452 (3) | 153 |
C10—H10B···O4i | 0.97 | 2.45 | 3.202 (3) | 134 |
N2—H1N···O3ii | 0.85 (3) | 2.02 (3) | 2.875 (3) | 175 (3) |
Symmetry codes: (i) −x+3/2, y, z−1/2; (ii) −x+1, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C17H16N2O2S |
Mr | 312.38 |
Crystal system, space group | Orthorhombic, Pccn |
Temperature (K) | 296 |
a, b, c (Å) | 13.9502 (8), 32.2588 (17), 6.9728 (3) |
V (Å3) | 3137.9 (3) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.22 |
Crystal size (mm) | 0.47 × 0.23 × 0.07 |
Data collection | |
Diffractometer | Bruker Kappa APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2007) |
Tmin, Tmax | 0.906, 0.985 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 16363, 3892, 2412 |
Rint | 0.044 |
(sin θ/λ)max (Å−1) | 0.667 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.055, 0.183, 1.00 |
No. of reflections | 3889 |
No. of parameters | 203 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.27, −0.20 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
C5—H5···O4i | 0.93 | 2.60 | 3.452 (3) | 153 |
C10—H10B···O4i | 0.97 | 2.45 | 3.202 (3) | 134 |
N2—H1N···O3ii | 0.85 (3) | 2.02 (3) | 2.875 (3) | 175 (3) |
Symmetry codes: (i) −x+3/2, y, z−1/2; (ii) −x+1, −y+1, −z+1. |
Acknowledgements
The authors acknowledge the Higher Education Commission, Pakistan, for providing funding for this research.
References
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Annulated pyrazines like quinoxalinones represents an important class of nitrogen containing heterocyclic compounds possessing wide variety of biological and industrial applications. The synthetic and naturally occurring quinoxalines compounds have been reported to show antibacterial (Ali et al., 2000) and antitumor (Moustafa & Yameda, 2001). In the present project we aimed to synthesize novel quinoxalinone derivatives which may have enhanced biological and pharmaceutical application.
The title compound (I) is in continuation of previously published work on the analoguous structure, 4-[(2,5-dimethylanilino)acetyl]-3,4- dihydroquinoxalin-2(1H)-one (II) (Nasir, et al., 2009). The dihedral angle between the aromatic ring (C1/C2/C3/C4/C5/C6) and pyrazinone (C1/C6/N2/C8/C7/N1)is 14.01 (12)°. Unlike (II) no intramolecular hydrogen bonding have been observed in (I). The N—H···O type intermolecular hydrogen bonding developed from the cyclic amido functional group forms the inversion dimers and produce eight membered ring motif R22(8) (Bernstein et al., 1995). Another C—H···O type hydrogen bonding interaction connects these dimers to another molecule Fig. 2. The benzyl ring (C12/C13/C14/C15/C16/C17) is oriented at dihedral angle of 14.01 (12)° and 30.45 (18)° with respect to aromatic and pyrazinone rings.