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Acta Cryst. (2008). E64, o606    [ doi:10.1107/S1600536808002924 ]

8,8-Dimethyl-5-(4-methylphenyl)-8,9-dihydropyrimido[4,5-b]quinoline-2,4,6(1H,3H,7H)-trione N,N-dimethylformamide solvate

J. Wang, S.-N. Ni and D. Shi

Abstract top

The title compound, C20H19N3O3·C3H7NO, was synthesized by the reaction of 6-aminopyrimidine-2,4(1H,3H)-dione and 4-methylbenzaldehyde with 5,5-dimethyl-1,3-cyclohexanedione in 1-butyl-3-methylimidazolium bromide at 363 K. The pyrimidine ring adopts a half-chair conformation while the six-membered ring fused to the pyridine ring adopts a skew-boat conformation. The dihedral angle between the pyridine ring and the attached benzene ring is 2.38(8)°

Comment top

The importance of uracil and its annelated derivatives is well recognized by synthetic (Sasaki et al., 1980; Bhuyan et al., 1999) as well as biological (Griengl et al., 1987; Pontikis et al., 1994) chemists. With the development of clinically useful anticancer and antiviral drugs (Clercq et al.,1986; Jones et al., 1979), there has recently been remarkable interest in the synthetic manipulations of uracils (Hirota et al., 1981). Pyrido[2,3-d]pyrimidines represent a heterocyclic ring system of considerable interest because of several biological activities associated with this scaffold. Some analogues have been found to act as anticancer agents inhibiting dihydrofolate reductases or tyrosine kinases (Gangjee et al., 1999), while others are known antiviral agents (Nasr et al., 2002).

The title compound was synthesized by the reaction of 6-aminopyrimidine-2,4(1H,3H)-dione and 4-methylbenzaldehyde with 5,5-dimethyl-1,3-cyclohexanedione using 1-butyl-3-methylimidazolium bromide ([bmim]Br) as solvent at 363 K.

In the title compound the pyridine ring (C13/C3/C4/C5/C12/N3) is a newly formed planar ring. The pyrimidine ring is less planar with atom C2 deviating from the C3/C1/C13/N1/N2 plane by -0.108 (3) Å (Fig. 1). The six-membered ring fused on to the pyridine ring adopts a skew-boat conformation; atoms C6, C5, C12 and C11 are coplanar, with atoms C7 and C8 deviating from the plane by -0.301 (2) and 0.458 (6) Å, respectively. The dihedral angle between the C13/C3/C4/C5/C12/N3 plane and the C3/C1/C13/N1/N2 plane is 2.38 (8) °, they are almost coplanar. The dihedral angle between the C13/C3/C4/C5/C12/N3 plane and the C14/C15/C16/C17/C19/C20 plane is 77.99 (5) °. The molecules are linked by N1—H1···O4 and N2—H2···O1 intermolecular hydrogen bonds (Table 1) to form dimers (Fig. 2).

Related literature top

For related literature, see: Bhuyan et al. (1999); Clercq (1986); Gangjee et al. (1999); Griengl et al. (1987); Hirota et al. (1981); Jones et al. (1979); Nasr & Gineinah (2002); Pontikis & Monneret (1994); Sasaki et al. (1980).

Experimental top

The title compound was prepared by the reaction of 6-aminopyrimidine-2,4(1H,3H)-dione (2 mmol) and 4-methylaldehyde (2 mmol) with 5,5-dimethyl-1,3-cyclohexanedione (2 mmol) in [bmim]Br (2 ml) at 363 K. Crystals of the title compound suitable for X-ray diffraction were obtained by slow evaporation of a N,N-dimethylformamide and water solution. 1H NMR (DMSO-d6, δ): 1.03 (6H, s, 2*CH3), 2.35 (3H, s, CH3), 2.40 (2H, s, CH2), 2.74 (3H, s, CH3), 2.90 (3H, s, CH3), 3.01 (2H, s, CH2), 6.89 (2H, d, J = 8.0 Hz, ArH), 7.08 (2H, d, J = 8.0 Hz, ArH), 7.96 (1H, s, CH), 11.12 (1H, s, NH), 11.88 (1H, s, NH).

Refinement top

The amino H atoms were located in a difference map and kept riding subsequently. The C-bound H atoms were placed in calculated positions, with C—H = 0.93–0.97 Å, and included in the final cycles of refinement using a riding model, with Uiso(H) = 1.2–1.5 Ueq(C).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SMART (Bruker, 1998); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing 40% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. The crystal packing of the title compound.
8,8-Dimethyl-5-(4-methylphenyl)-8,9-dihydropyrimido[4,5-b]quinoline- 2,4,6(1H,3H,7H)-trione N,N-dimethylformamide solvate top
Crystal data top
C20H19N3O3·C3H7NOZ = 2
Mr = 422.48F000 = 448
Triclinic, P1Dx = 1.268 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 8.8252 (16) ÅCell parameters from 2318 reflections
b = 10.289 (2) Åθ = 2.5–26.3º
c = 12.316 (2) ŵ = 0.09 mm−1
α = 95.898 (3)ºT = 294 (2) K
β = 93.115 (3)ºBlock, colorless
γ = 94.719 (3)º0.24 × 0.16 × 0.12 mm
V = 1106.4 (4) Å3
Data collection top
Bruker SMART 1000
diffractometer		4285 independent reflections
Radiation source: fine-focus sealed tube2833 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.018
T = 294(2) Kθmax = 26.0º
φ and ω scansθmin = 1.7º
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −9→10
Tmin = 0.978, Tmax = 0.989k = −10→12
6083 measured reflectionsl = −15→11
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.045H-atom parameters constrained
wR(F2) = 0.134  w = 1/[σ2(Fo2) + (0.0627P)2 + 0.2466P]
where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max < 0.001
4285 reflectionsΔρmax = 0.25 e Å−3
285 parametersΔρmin = −0.23 e Å−3
1 restraintExtinction correction: none
Primary atom site location: structure-invariant direct methods
Crystal data top
C20H19N3O3·C3H7NOγ = 94.719 (3)º
Mr = 422.48V = 1106.4 (4) Å3
Triclinic, P1Z = 2
a = 8.8252 (16) ÅMo Kα
b = 10.289 (2) ŵ = 0.09 mm−1
c = 12.316 (2) ÅT = 294 (2) K
α = 95.898 (3)º0.24 × 0.16 × 0.12 mm
β = 93.115 (3)º
Data collection top
Bruker SMART 1000
diffractometer		4285 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2833 reflections with I > 2σ(I)
Tmin = 0.978, Tmax = 0.989Rint = 0.018
6083 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0451 restraint
wR(F2) = 0.134H-atom parameters constrained
S = 1.00Δρmax = 0.25 e Å−3
4285 reflectionsΔρmin = −0.23 e Å−3
285 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.66314 (15)0.41510 (14)0.49822 (12)0.0587 (4)
O20.61458 (17)0.01747 (15)0.62264 (14)0.0726 (5)
O30.1315 (2)−0.03738 (19)0.88397 (19)0.1117 (8)
N10.63982 (17)0.22017 (16)0.56995 (13)0.0485 (4)
H10.73000.20420.54310.058*
N20.45129 (17)0.36219 (16)0.58594 (14)0.0503 (4)
H20.41120.43580.57040.060*
N30.24137 (17)0.32697 (15)0.68299 (13)0.0475 (4)
C10.5892 (2)0.33743 (19)0.54821 (16)0.0456 (5)
C20.5624 (2)0.1225 (2)0.62047 (16)0.0474 (5)
C30.42031 (19)0.15976 (18)0.66859 (14)0.0411 (4)
C40.3337 (2)0.08197 (18)0.73401 (14)0.0404 (4)
C50.1967 (2)0.12798 (18)0.76963 (15)0.0438 (4)
C60.0920 (2)0.0536 (2)0.83849 (18)0.0556 (5)
C7−0.0623 (2)0.10073 (19)0.85164 (18)0.0533 (5)
H7A−0.10910.06040.91080.064*
H7B−0.12590.07370.78510.064*
C8−0.0549 (2)0.25028 (19)0.87620 (16)0.0473 (5)
C90.0437 (3)0.2941 (2)0.98100 (19)0.0691 (6)
H9A0.04560.38750.99720.104*
H9B0.14550.27030.97160.104*
H9C0.00230.25201.04020.104*
C10−0.2145 (2)0.2942 (2)0.8905 (2)0.0650 (6)
H10A−0.25670.25740.95200.098*
H10B−0.27850.26470.82560.098*
H10C−0.20880.38820.90290.098*
C110.0129 (2)0.3077 (2)0.77834 (18)0.0544 (5)
H11A−0.06310.29440.71740.065*
H11B0.03500.40160.79660.065*
C120.1560 (2)0.25081 (18)0.74199 (16)0.0458 (5)
C130.36838 (19)0.27982 (18)0.64708 (15)0.0420 (4)
C140.38754 (19)−0.04296 (18)0.76792 (14)0.0398 (4)
C150.3251 (2)−0.16362 (19)0.71966 (16)0.0503 (5)
H150.2520−0.16840.66180.060*
C160.3704 (2)−0.2778 (2)0.75669 (18)0.0558 (5)
H160.3266−0.35840.72350.067*
C170.4790 (2)−0.2743 (2)0.84175 (17)0.0530 (5)
C180.5257 (3)−0.4007 (3)0.8817 (2)0.0871 (8)
H18A0.6009−0.43550.83620.131*
H18B0.4381−0.46320.87830.131*
H18C0.5675−0.38330.95590.131*
C190.5433 (2)−0.1537 (2)0.88808 (17)0.0548 (5)
H190.6181−0.14930.94480.066*
C200.4988 (2)−0.0388 (2)0.85185 (16)0.0485 (5)
H200.54420.04170.88420.058*
O4−0.06364 (17)0.16079 (19)0.51009 (14)0.0800 (5)
N40.09249 (19)0.25425 (17)0.39330 (15)0.0582 (5)
C210.0462 (2)0.1599 (3)0.45278 (19)0.0658 (6)
H210.10160.08680.45100.079*
C220.0147 (3)0.3718 (2)0.3888 (3)0.0941 (10)
H22A−0.06870.36940.43570.141*
H22B−0.02340.37720.31510.141*
H22C0.08450.44720.41280.141*
C230.2201 (3)0.2428 (3)0.3249 (2)0.0797 (8)
H23A0.26740.16430.33680.120*
H23B0.29280.31760.34310.120*
H23C0.18460.23900.24950.120*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0489 (8)0.0557 (9)0.0800 (10)0.0090 (6)0.0278 (7)0.0317 (7)
O20.0714 (10)0.0658 (10)0.0973 (12)0.0368 (8)0.0439 (9)0.0436 (9)
O30.1149 (15)0.0955 (14)0.1588 (19)0.0597 (12)0.0936 (14)0.0921 (14)
N10.0396 (8)0.0558 (10)0.0574 (10)0.0151 (7)0.0189 (7)0.0236 (8)
N20.0446 (9)0.0477 (9)0.0676 (11)0.0153 (7)0.0225 (8)0.0298 (8)
N30.0434 (8)0.0466 (9)0.0597 (10)0.0131 (7)0.0181 (7)0.0249 (8)
C10.0395 (10)0.0480 (11)0.0535 (11)0.0077 (8)0.0124 (9)0.0168 (9)
C20.0473 (11)0.0521 (12)0.0497 (11)0.0165 (9)0.0143 (9)0.0232 (9)
C30.0396 (10)0.0441 (10)0.0441 (10)0.0110 (8)0.0097 (8)0.0163 (8)
C40.0429 (10)0.0408 (10)0.0412 (10)0.0100 (8)0.0087 (8)0.0132 (8)
C50.0440 (10)0.0443 (11)0.0478 (11)0.0098 (8)0.0142 (8)0.0162 (8)
C60.0633 (13)0.0447 (11)0.0665 (13)0.0131 (10)0.0296 (11)0.0229 (10)
C70.0485 (11)0.0497 (12)0.0646 (13)0.0020 (9)0.0198 (10)0.0141 (10)
C80.0420 (10)0.0464 (11)0.0575 (12)0.0090 (8)0.0173 (9)0.0138 (9)
C90.0749 (15)0.0634 (15)0.0693 (15)0.0109 (12)0.0075 (12)0.0036 (12)
C100.0516 (12)0.0669 (15)0.0824 (16)0.0141 (11)0.0280 (11)0.0164 (12)
C110.0459 (11)0.0571 (13)0.0687 (13)0.0190 (9)0.0227 (10)0.0263 (10)
C120.0432 (10)0.0462 (11)0.0533 (11)0.0113 (8)0.0145 (9)0.0194 (9)
C130.0376 (9)0.0447 (11)0.0484 (11)0.0088 (8)0.0120 (8)0.0190 (8)
C140.0409 (9)0.0410 (10)0.0422 (10)0.0103 (8)0.0136 (8)0.0163 (8)
C150.0527 (11)0.0477 (12)0.0514 (12)0.0066 (9)−0.0011 (9)0.0113 (9)
C160.0631 (13)0.0389 (11)0.0670 (14)0.0073 (9)0.0069 (11)0.0095 (10)
C170.0564 (12)0.0500 (13)0.0601 (13)0.0194 (10)0.0158 (10)0.0236 (10)
C180.0965 (19)0.0673 (17)0.109 (2)0.0288 (14)0.0107 (16)0.0448 (15)
C190.0550 (12)0.0627 (14)0.0508 (12)0.0155 (10)−0.0006 (10)0.0198 (10)
C200.0520 (11)0.0463 (11)0.0483 (11)0.0042 (9)0.0019 (9)0.0116 (9)
O40.0493 (9)0.1184 (15)0.0802 (11)0.0195 (9)0.0241 (8)0.0278 (10)
N40.0482 (10)0.0595 (11)0.0705 (12)0.0154 (8)0.0172 (9)0.0086 (9)
C210.0501 (12)0.0872 (18)0.0675 (15)0.0244 (12)0.0143 (11)0.0229 (13)
C220.0639 (15)0.0549 (15)0.166 (3)0.0120 (12)0.0356 (17)0.0052 (16)
C230.0733 (16)0.0849 (18)0.0918 (19)0.0286 (14)0.0400 (14)0.0257 (15)
Geometric parameters (Å, °) top
O1—C11.226 (2)C10—H10C0.9600
O2—C21.211 (2)C11—C121.506 (2)
O3—C61.205 (2)C11—H11A0.9700
N1—C11.367 (2)C11—H11B0.9700
N1—C21.388 (2)C14—C151.378 (3)
N1—H10.8997C14—C201.382 (3)
N2—C11.360 (2)C15—C161.383 (3)
N2—C131.382 (2)C15—H150.9300
N2—H20.8952C16—C171.377 (3)
N3—C131.337 (2)C16—H160.9300
N3—C121.338 (2)C17—C191.375 (3)
C2—C31.478 (2)C17—C181.516 (3)
C3—C131.398 (2)C18—H18A0.9600
C3—C41.405 (2)C18—H18B0.9600
C4—C51.409 (2)C18—H18C0.9600
C4—C141.497 (2)C19—C201.384 (3)
C5—C121.411 (2)C19—H190.9300
C5—C61.503 (2)C20—H200.9300
C6—C71.495 (3)O4—C211.230 (2)
C7—C81.533 (3)N4—C211.326 (3)
C7—H7A0.9700N4—C221.444 (3)
C7—H7B0.9700N4—C231.447 (3)
C8—C91.523 (3)C21—H210.9300
C8—C111.526 (3)C22—H22A0.9600
C8—C101.528 (3)C22—H22B0.9600
C9—H9A0.9600C22—H22C0.9600
C9—H9B0.9600C23—H23A0.9600
C9—H9C0.9600C23—H23B0.9600
C10—H10A0.9600C23—H23C0.9600
C10—H10B0.9600
C1—N1—C2127.04 (15)C12—C11—H11B108.5
C1—N1—H1114.5C8—C11—H11B108.5
C2—N1—H1118.3H11A—C11—H11B107.5
C1—N2—C13123.74 (15)N3—C12—C5123.18 (16)
C1—N2—H2118.6N3—C12—C11114.43 (16)
C13—N2—H2117.6C5—C12—C11122.38 (16)
C13—N3—C12116.77 (15)N3—C13—N2114.21 (15)
O1—C1—N2122.24 (17)N3—C13—C3125.32 (15)
O1—C1—N1122.30 (16)N2—C13—C3120.46 (15)
N2—C1—N1115.46 (16)C15—C14—C20118.52 (17)
O2—C2—N1119.28 (17)C15—C14—C4121.53 (17)
O2—C2—C3125.96 (17)C20—C14—C4119.91 (17)
N1—C2—C3114.75 (16)C14—C15—C16120.51 (19)
C13—C3—C4117.92 (15)C14—C15—H15119.7
C13—C3—C2117.88 (15)C16—C15—H15119.7
C4—C3—C2124.20 (16)C17—C16—C15121.3 (2)
C3—C4—C5117.59 (16)C17—C16—H16119.4
C3—C4—C14121.21 (15)C15—C16—H16119.4
C5—C4—C14121.17 (15)C19—C17—C16117.98 (18)
C4—C5—C12119.14 (16)C19—C17—C18121.7 (2)
C4—C5—C6123.10 (16)C16—C17—C18120.4 (2)
C12—C5—C6117.74 (16)C17—C18—H18A109.5
O3—C6—C7121.12 (18)C17—C18—H18B109.5
O3—C6—C5121.92 (19)H18A—C18—H18B109.5
C7—C6—C5116.92 (17)C17—C18—H18C109.5
C6—C7—C8111.96 (16)H18A—C18—H18C109.5
C6—C7—H7A109.2H18B—C18—H18C109.5
C8—C7—H7A109.2C17—C19—C20121.29 (19)
C6—C7—H7B109.2C17—C19—H19119.4
C8—C7—H7B109.2C20—C19—H19119.4
H7A—C7—H7B107.9C14—C20—C19120.40 (19)
C9—C8—C11111.19 (18)C14—C20—H20119.8
C9—C8—C10108.88 (18)C19—C20—H20119.8
C11—C8—C10109.94 (16)C21—N4—C22122.15 (19)
C9—C8—C7109.80 (17)C21—N4—C23121.93 (19)
C11—C8—C7106.70 (16)C22—N4—C23115.86 (19)
C10—C8—C7110.32 (16)O4—C21—N4125.7 (2)
C8—C9—H9A109.5O4—C21—H21117.2
C8—C9—H9B109.5N4—C21—H21117.2
H9A—C9—H9B109.5N4—C22—H22A109.5
C8—C9—H9C109.5N4—C22—H22B109.5
H9A—C9—H9C109.5H22A—C22—H22B109.5
H9B—C9—H9C109.5N4—C22—H22C109.5
C8—C10—H10A109.5H22A—C22—H22C109.5
C8—C10—H10B109.5H22B—C22—H22C109.5
H10A—C10—H10B109.5N4—C23—H23A109.5
C8—C10—H10C109.5N4—C23—H23B109.5
H10A—C10—H10C109.5H23A—C23—H23B109.5
H10B—C10—H10C109.5N4—C23—H23C109.5
C12—C11—C8114.94 (16)H23A—C23—H23C109.5
C12—C11—H11A108.5H23B—C23—H23C109.5
C8—C11—H11A108.5
C13—N2—C1—O1−176.75 (19)C13—N3—C12—C11−178.87 (17)
C13—N2—C1—N13.2 (3)C4—C5—C12—N30.0 (3)
C2—N1—C1—O1−176.3 (2)C6—C5—C12—N3178.69 (19)
C2—N1—C1—N23.8 (3)C4—C5—C12—C11−179.04 (18)
C1—N1—C2—O2171.4 (2)C6—C5—C12—C11−0.4 (3)
C1—N1—C2—C3−9.2 (3)C8—C11—C12—N3−159.06 (18)
O2—C2—C3—C13−172.7 (2)C8—C11—C12—C520.1 (3)
N1—C2—C3—C138.0 (3)C12—N3—C13—N2179.51 (17)
O2—C2—C3—C47.0 (3)C12—N3—C13—C3−1.7 (3)
N1—C2—C3—C4−172.41 (18)C1—N2—C13—N3175.18 (18)
C13—C3—C4—C52.6 (3)C1—N2—C13—C3−3.7 (3)
C2—C3—C4—C5−176.97 (18)C4—C3—C13—N3−0.6 (3)
C13—C3—C4—C14−175.28 (17)C2—C3—C13—N3179.01 (18)
C2—C3—C4—C145.1 (3)C4—C3—C13—N2178.07 (17)
C3—C4—C5—C12−2.4 (3)C2—C3—C13—N2−2.3 (3)
C14—C4—C5—C12175.53 (18)C3—C4—C14—C15−104.4 (2)
C3—C4—C5—C6179.03 (18)C5—C4—C14—C1577.8 (2)
C14—C4—C5—C6−3.1 (3)C3—C4—C14—C2077.8 (2)
C4—C5—C6—O313.9 (4)C5—C4—C14—C20−100.1 (2)
C12—C5—C6—O3−164.7 (2)C20—C14—C15—C161.7 (3)
C4—C5—C6—C7−168.34 (19)C4—C14—C15—C16−176.17 (17)
C12—C5—C6—C713.1 (3)C14—C15—C16—C17−0.4 (3)
O3—C6—C7—C8132.9 (3)C15—C16—C17—C19−1.0 (3)
C5—C6—C7—C8−45.0 (3)C15—C16—C17—C18179.4 (2)
C6—C7—C8—C9−59.3 (2)C16—C17—C19—C201.0 (3)
C6—C7—C8—C1161.3 (2)C18—C17—C19—C20−179.3 (2)
C6—C7—C8—C10−179.26 (18)C15—C14—C20—C19−1.6 (3)
C9—C8—C11—C1270.9 (2)C4—C14—C20—C19176.28 (17)
C10—C8—C11—C12−168.42 (18)C17—C19—C20—C140.3 (3)
C7—C8—C11—C12−48.8 (2)C22—N4—C21—O4−0.6 (4)
C13—N3—C12—C52.0 (3)C23—N4—C21—O4−177.7 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O4i0.901.962.854 (2)170
N2—H2···O1ii0.901.972.846 (2)167
Symmetry codes: (i) x+1, y, z; (ii) −x+1, −y+1, −z+1.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O4i0.901.962.854 (2)170
N2—H2···O1ii0.901.972.846 (2)167
Symmetry codes: (i) x+1, y, z; (ii) −x+1, −y+1, −z+1.
Acknowledgements top

The authors are grateful to the Foundation of the Key Laboratory of Biotechnology on Medical Plants of Jiangsu Province for financial support.

references
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