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Acta Cryst. (2009). E65, o523-o524    [ doi:10.1107/S1600536809004693 ]

N-(1-Naphthyl)-10H-9-oxa-1,3-diazaanthracen-4-amine

H.-K. Fun, S. Chantrapromma, S. Rai, P. Shetty and A. M. Isloor

Abstract top

In the molecule of the title compound, C21H15N3O, the 10H-9-oxa-1,3-diazaanthracene ring system is slightly bent, with dihedral angles of 3.99 (6) and 4.80 (6)° between the pyran ring and the pyrimidine and benzene rings, respectively. This ring system makes a dihedral angle of 85.23 (3)° with the naphthalene plane. In the crystal packing, molecules are linked by N-H...N hydrogen bonds into chains along the a axis and these chains are stacked along the b axis. The crystal is further stabilized by weak C-H...N and C-H...[pi] interactions.

Comment top

Condensed heterocyclic systems are of considerable interest not only because of their potential biological activity but also because of their versatility as synthons in organic transformations (Bohme & Haake, 1976; Taylor & McKillop, 1970; Erian, 1993). A series of 1,6-naphthyrimidines have been demonstrated to possess antihuman cytomegalovirus (HCMV) activity (Falardeau et al., 2000; Bedard et al., 2000). Furthermore, chromenes and their fused heterocyclic derivatives have attracted a great deal of interest due to their wide applications in the field of pharmaceuticals (Martinez & Marco, 1997; Tandon et al., 1991). In view of these observations, we have synthesized title compound which is a new chromenopyrimidine molecule and its crystal structure was reported here.

In the structure of the title compound (I) (Fig. 1), the 10H-9-oxa-1,3-diaza-anthracene ring system is slightly bent as indicated by the dihedral angles between the central ring and the two side rings being 3.99 (6)° (for the C1–C3/C11/N1–N2 ring) and 4.80 (6)° (for the C4–C9 ring). The naphthalene ring system is planar with the largest deviation 0.027 (1) Å for atom C9. The 10H-9-oxa-1,3-diaza-anthracene ring is almost perpendicular with the naphthalene ring as shown by the dihedral angle between these two ring systems being 83.00 (15)°. The naphthalene–amine moiety (N3/C12–C21) is in (+)-syn-clinal with respect to the C1–C3/C11/N1–N2 ring with a torsion angle C1—N3—C12–C21 = 83.00 (15)°. The bond distances have normal values (Allen et al., 1987).

In the crystal packing, N—H···N hydrogen bonds (Table 1, Fig. 2) link the molecules into chains along the a axis and these molecular chains are stacked along the b axis. The crystal is further stabilized by weak C—H···N and C—H···π interactions; Cg1 and Cg2 are the centroids of C1–C3/C11/N1–N2 and C4–C9 rings, respectively (Table 1).

Related literature top

For values of bond lengths, see Allen et al. (1987). For background to the bioactivity and applications of naphthyrimidines, see, for example: Bedard et al. (2000); Bohme & Haake (1976); Erian (1993); Falardeau et al. (2000); Martinez & Marco (1997); Tandon et al. (1991); Taylor & McKillop (1970). For stability of temperature controller, see Cosier & Glazer (1986).

Experimental top

The title compound was obtained by vigorously stirring a solution of 2-amino-4H-chromene-3-carbonitrile 0.5 g (2.8 mmol) in 10 ml of dimethyl formamide dimethylacetal which has been heated to reflux for 2 h. Excess dimethyl formamide dimethyl acetal was removed and the residue obtained was dissolved in acetic acid (10 ml). Amine 0.41 g (2.8 mmol) was then added and heated to reflux for an additional 2 h. The reaction mixture was concentrated and finally the residue was purified by column chromatography using petroleum ether–ethyl acetate (60:40 v/v) to get desired compound as a crystalline solid 0.59 g (Yield 63%, m.p. 513–515 K).

Refinement top

The amine H atom was located in a difference map and refined isotropically. The remaining H atoms were placed in calculated positions with d(C—H) = 0.93 Å, Uiso = 1.2Ueq(C) for aromatic and 0.97 Å, Uiso = 1.2Ueq(C) for CH2. The highest residual electron density peak is located at 0.58 Å from C18 and the deepest hole is located at 0.69 Å from C3.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (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, 2003).

Figures top
[Figure 1] Fig. 1. The structure of (I), showing 50% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. The packing diagram of (I), viewed along the b axis, showing molecular chains along the a axis. Hydrogen bonds are shown as dashed lines.
N-(1-Naphthyl)-10H-9-oxa-1,3-diazaanthracen-4-amine top
Crystal data top
C21H15N3ODx = 1.349 Mg m−3
Mr = 325.36Melting point = 513–515 K
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 4673 reflections
a = 13.2762 (3) Åθ = 1.5–30.0°
b = 8.8700 (2) ŵ = 0.09 mm−1
c = 27.1997 (5) ÅT = 100 K
V = 3203.03 (12) Å3Plate, colourless
Z = 80.57 × 0.38 × 0.03 mm
F(000) = 1360
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer		4673 independent reflections
Radiation source: fine-focus sealed tube3649 reflections with I > 2σ(I)
graphiteRint = 0.042
Detector resolution: 8.33 pixels mm-1θmax = 30.0°, θmin = 1.5°
ω scansh = −18→18
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		k = −12→12
Tmin = 0.901, Tmax = 0.997l = −37→38
27104 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.142H atoms treated by a mixture of independent and constrained refinement
S = 1.08 w = 1/[σ2(Fo2) + (0.0844P)2 + 0.3525P]
where P = (Fo2 + 2Fc2)/3
4673 reflections(Δ/σ)max = 0.001
230 parametersΔρmax = 0.35 e Å−3
0 restraintsΔρmin = −0.33 e Å−3
Crystal data top
C21H15N3OV = 3203.03 (12) Å3
Mr = 325.36Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 13.2762 (3) ŵ = 0.09 mm−1
b = 8.8700 (2) ÅT = 100 K
c = 27.1997 (5) Å0.57 × 0.38 × 0.03 mm
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer		4673 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		3649 reflections with I > 2σ(I)
Tmin = 0.901, Tmax = 0.997Rint = 0.042
27104 measured reflectionsθmax = 30.0°
Refinement top
R[F2 > 2σ(F2)] = 0.045H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.142Δρmax = 0.35 e Å−3
S = 1.08Δρmin = −0.33 e Å−3
4673 reflectionsAbsolute structure: ?
230 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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
xyzUiso*/Ueq
O10.08414 (6)0.31457 (10)0.18202 (3)0.0193 (2)
N10.18466 (7)0.51429 (12)0.30718 (4)0.0183 (2)
N20.05453 (7)0.44680 (12)0.25056 (3)0.0180 (2)
N30.35056 (7)0.44664 (13)0.29448 (3)0.0182 (2)
H1N30.4016 (12)0.4226 (19)0.2734 (6)0.034 (4)*
C10.25345 (8)0.44337 (14)0.27880 (4)0.0156 (2)
C20.09044 (9)0.51210 (15)0.29118 (4)0.0184 (2)
H2A0.04350.56220.31060.022*
C30.12498 (8)0.37767 (14)0.22322 (4)0.0163 (2)
C40.14513 (9)0.22381 (14)0.15270 (4)0.0174 (2)
C50.09574 (9)0.15384 (16)0.11364 (4)0.0220 (3)
H5A0.02770.17160.10810.026*
C60.14946 (10)0.05735 (16)0.08316 (4)0.0245 (3)
H6A0.11750.01000.05690.029*
C70.25153 (10)0.03159 (16)0.09199 (4)0.0234 (3)
H7A0.2873−0.03520.07230.028*
C80.29956 (9)0.10591 (15)0.13028 (4)0.0202 (3)
H8A0.36790.08930.13550.024*
C90.24765 (8)0.20522 (14)0.16123 (4)0.0169 (2)
C100.30044 (8)0.29292 (15)0.20116 (4)0.0178 (2)
H10A0.34200.22490.22040.021*
H10B0.34420.36770.18630.021*
C110.22622 (8)0.37036 (14)0.23449 (4)0.0156 (2)
C120.37886 (8)0.52034 (15)0.33935 (4)0.0175 (2)
C130.41910 (9)0.66208 (16)0.33759 (4)0.0218 (3)
H13A0.42740.70970.30740.026*
C140.44831 (10)0.73748 (16)0.38139 (5)0.0247 (3)
H14A0.47480.83440.37980.030*
C150.43757 (9)0.66800 (16)0.42576 (5)0.0240 (3)
H15A0.45600.71850.45430.029*
C160.39841 (9)0.51891 (16)0.42882 (4)0.0210 (3)
C170.38629 (10)0.44401 (18)0.47457 (4)0.0273 (3)
H17A0.40350.49370.50350.033*
C180.34979 (10)0.30001 (19)0.47687 (5)0.0310 (3)
H18A0.34250.25270.50720.037*
C190.32313 (10)0.22321 (18)0.43346 (5)0.0272 (3)
H19A0.30010.12430.43520.033*
C200.33080 (9)0.29311 (16)0.38844 (4)0.0215 (3)
H20A0.31130.24220.36010.026*
C210.36831 (8)0.44257 (15)0.38505 (4)0.0179 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0145 (4)0.0257 (5)0.0178 (4)0.0017 (3)−0.0020 (3)−0.0046 (3)
N10.0160 (5)0.0215 (5)0.0175 (4)0.0021 (4)0.0008 (3)−0.0018 (4)
N20.0145 (4)0.0211 (5)0.0183 (4)0.0019 (4)−0.0010 (3)0.0001 (4)
N30.0128 (4)0.0267 (6)0.0152 (4)0.0008 (4)−0.0012 (3)−0.0035 (4)
C10.0141 (5)0.0170 (6)0.0156 (4)0.0002 (4)−0.0003 (4)0.0016 (4)
C20.0163 (5)0.0212 (6)0.0178 (5)0.0019 (5)0.0020 (4)−0.0005 (4)
C30.0167 (5)0.0181 (6)0.0141 (4)0.0002 (5)−0.0002 (4)0.0009 (4)
C40.0174 (5)0.0189 (6)0.0158 (5)−0.0008 (5)0.0009 (4)0.0005 (4)
C50.0202 (6)0.0272 (7)0.0186 (5)−0.0035 (5)−0.0012 (4)0.0005 (5)
C60.0279 (6)0.0277 (7)0.0178 (5)−0.0051 (5)−0.0005 (4)−0.0030 (5)
C70.0279 (6)0.0238 (7)0.0185 (5)−0.0003 (5)0.0052 (5)−0.0019 (5)
C80.0205 (5)0.0217 (6)0.0182 (5)0.0016 (5)0.0033 (4)0.0015 (5)
C90.0183 (5)0.0177 (6)0.0148 (4)−0.0004 (4)0.0011 (4)0.0009 (4)
C100.0138 (5)0.0225 (6)0.0171 (5)0.0012 (4)0.0001 (4)−0.0019 (4)
C110.0152 (5)0.0173 (6)0.0144 (4)0.0008 (4)−0.0001 (4)0.0006 (4)
C120.0131 (5)0.0227 (6)0.0167 (5)0.0023 (4)−0.0006 (4)−0.0028 (4)
C130.0198 (6)0.0243 (7)0.0213 (5)0.0001 (5)−0.0028 (4)0.0021 (5)
C140.0228 (6)0.0215 (6)0.0297 (6)−0.0039 (5)−0.0053 (5)−0.0025 (5)
C150.0211 (6)0.0282 (7)0.0227 (5)−0.0001 (5)−0.0047 (4)−0.0069 (5)
C160.0160 (5)0.0288 (7)0.0183 (5)0.0003 (5)−0.0015 (4)−0.0033 (5)
C170.0223 (6)0.0427 (9)0.0169 (5)−0.0020 (6)−0.0022 (4)−0.0014 (5)
C180.0262 (6)0.0453 (9)0.0214 (6)−0.0048 (6)−0.0008 (5)0.0080 (6)
C190.0220 (6)0.0311 (8)0.0285 (6)−0.0060 (6)−0.0003 (5)0.0049 (6)
C200.0173 (5)0.0252 (7)0.0218 (5)−0.0017 (5)−0.0003 (4)−0.0016 (5)
C210.0128 (5)0.0233 (6)0.0176 (5)0.0019 (5)−0.0007 (4)−0.0026 (5)
Geometric parameters (Å, °) top
O1—C31.3649 (13)C9—C101.5085 (16)
O1—C41.3927 (14)C10—C111.5050 (15)
N1—C21.3245 (15)C10—H10A0.9700
N1—C11.3511 (14)C10—H10B0.9700
N2—C21.3355 (15)C12—C131.3669 (19)
N2—C31.3432 (15)C12—C211.4287 (16)
N3—C11.3582 (14)C13—C141.4202 (17)
N3—C121.4345 (14)C13—H13A0.9300
N3—H1N30.913 (17)C14—C151.3626 (18)
C1—C111.4151 (15)C14—H14A0.9300
C2—H2A0.9300C15—C161.4234 (19)
C3—C111.3800 (15)C15—H15A0.9300
C4—C91.3905 (16)C16—C171.4198 (17)
C4—C51.3943 (16)C16—C211.4266 (16)
C5—C61.3886 (18)C17—C181.368 (2)
C5—H5A0.9300C17—H17A0.9300
C6—C71.3951 (19)C18—C191.4082 (19)
C6—H6A0.9300C18—H18A0.9300
C7—C81.3878 (17)C19—C201.3764 (17)
C7—H7A0.9300C19—H19A0.9300
C8—C91.3999 (16)C20—C211.4191 (19)
C8—H8A0.9300C20—H20A0.9300
C3—O1—C4118.43 (9)C11—C10—H10B109.3
C2—N1—C1116.35 (10)C9—C10—H10B109.3
C2—N2—C3114.05 (10)H10A—C10—H10B108.0
C1—N3—C12121.70 (10)C3—C11—C1114.62 (10)
C1—N3—H1N3120.1 (10)C3—C11—C10121.68 (10)
C12—N3—H1N3116.5 (10)C1—C11—C10123.68 (10)
N1—C1—N3116.89 (10)C13—C12—C21120.85 (11)
N1—C1—C11121.79 (10)C13—C12—N3119.46 (11)
N3—C1—C11121.31 (10)C21—C12—N3119.64 (11)
N1—C2—N2127.97 (11)C12—C13—C14120.70 (11)
N1—C2—H2A116.0C12—C13—H13A119.6
N2—C2—H2A116.0C14—C13—H13A119.6
N2—C3—O1111.42 (9)C15—C14—C13120.09 (12)
N2—C3—C11125.21 (10)C15—C14—H14A120.0
O1—C3—C11123.37 (10)C13—C14—H14A120.0
C9—C4—O1122.82 (10)C14—C15—C16120.68 (11)
C9—C4—C5122.33 (11)C14—C15—H15A119.7
O1—C4—C5114.85 (10)C16—C15—H15A119.7
C6—C5—C4119.18 (11)C17—C16—C15121.83 (11)
C6—C5—H5A120.4C17—C16—C21118.52 (12)
C4—C5—H5A120.4C15—C16—C21119.64 (11)
C5—C6—C7119.81 (11)C18—C17—C16121.15 (12)
C5—C6—H6A120.1C18—C17—H17A119.4
C7—C6—H6A120.1C16—C17—H17A119.4
C8—C7—C6119.84 (12)C17—C18—C19120.17 (12)
C8—C7—H7A120.1C17—C18—H18A119.9
C6—C7—H7A120.1C19—C18—H18A119.9
C7—C8—C9121.60 (11)C20—C19—C18120.62 (14)
C7—C8—H8A119.2C20—C19—H19A119.7
C9—C8—H8A119.2C18—C19—H19A119.7
C4—C9—C8117.14 (10)C19—C20—C21120.30 (12)
C4—C9—C10120.92 (10)C19—C20—H20A119.8
C8—C9—C10121.91 (10)C21—C20—H20A119.8
C11—C10—C9111.40 (9)C20—C21—C16119.18 (11)
C11—C10—H10A109.3C20—C21—C12122.82 (11)
C9—C10—H10A109.3C16—C21—C12118.00 (11)
C2—N1—C1—N3179.12 (11)N1—C1—C11—C3−0.19 (17)
C2—N1—C1—C11−0.19 (17)N3—C1—C11—C3−179.46 (11)
C12—N3—C1—N10.71 (17)N1—C1—C11—C10178.62 (11)
C12—N3—C1—C11−179.98 (11)N3—C1—C11—C10−0.66 (18)
C1—N1—C2—N20.81 (19)C9—C10—C11—C3−10.17 (16)
C3—N2—C2—N1−0.92 (19)C9—C10—C11—C1171.11 (11)
C2—N2—C3—O1−179.33 (10)C1—N3—C12—C13−99.41 (14)
C2—N2—C3—C110.44 (18)C1—N3—C12—C2183.00 (15)
C4—O1—C3—N2−172.67 (10)C21—C12—C13—C14−2.11 (18)
C4—O1—C3—C117.55 (17)N3—C12—C13—C14−179.66 (11)
C3—O1—C4—C9−5.68 (16)C12—C13—C14—C150.8 (2)
C3—O1—C4—C5174.98 (11)C13—C14—C15—C160.9 (2)
C9—C4—C5—C62.60 (19)C14—C15—C16—C17−179.90 (12)
O1—C4—C5—C6−178.05 (11)C14—C15—C16—C21−1.21 (18)
C4—C5—C6—C70.09 (19)C15—C16—C17—C18−179.14 (12)
C5—C6—C7—C8−1.9 (2)C21—C16—C17—C182.15 (19)
C6—C7—C8—C91.13 (19)C16—C17—C18—C19−0.2 (2)
O1—C4—C9—C8177.40 (11)C17—C18—C19—C20−1.8 (2)
C5—C4—C9—C8−3.31 (18)C18—C19—C20—C211.7 (2)
O1—C4—C9—C10−4.59 (17)C19—C20—C21—C160.33 (18)
C5—C4—C9—C10174.71 (11)C19—C20—C21—C12179.40 (12)
C7—C8—C9—C41.42 (18)C17—C16—C21—C20−2.21 (17)
C7—C8—C9—C10−176.57 (12)C15—C16—C21—C20179.06 (11)
C4—C9—C10—C1111.79 (16)C17—C16—C21—C12178.68 (11)
C8—C9—C10—C11−170.29 (11)C15—C16—C21—C12−0.06 (17)
N2—C3—C11—C10.05 (18)C13—C12—C21—C20−177.38 (11)
O1—C3—C11—C1179.80 (10)N3—C12—C21—C200.17 (17)
N2—C3—C11—C10−178.78 (11)C13—C12—C21—C161.70 (17)
O1—C3—C11—C100.97 (18)N3—C12—C21—C16179.25 (10)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H1N3···N2i0.913 (16)2.143 (16)2.9722 (13)150.6 (14)
C13—H13A···N2ii0.932.623.4791 (16)154
C20—H20A···N30.932.602.9077 (15)100
C20—H20A···N1iii0.932.483.3232 (17)150
C10—H10A···Cg1iii0.972.763.5855 (14)143
C10—H10B···Cg2ii0.972.963.6792 (14)132
C13—H13A···Cg1ii0.932.633.3503 (14)135
Symmetry codes: (i) x+1/2, y, −z+1/2; (ii) −x+1/2, y+1/2, z; (iii) −x+1/2, y−1/2, z.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H1N3···N2i0.913 (16)2.143 (16)2.9722 (13)150.6 (14)
C13—H13A···N2ii0.932.623.4791 (16)154
C20—H20A···N30.932.602.9077 (15)100
C20—H20A···N1iii0.932.483.3232 (17)150
C10—H10A···Cg1iii0.972.763.5855 (14)143
C10—H10B···Cg2ii0.972.963.6792 (14)132
C13—H13A···Cg1ii0.932.633.3503 (14)135
Symmetry codes: (i) x+1/2, y, −z+1/2; (ii) −x+1/2, y+1/2, z; (iii) −x+1/2, y−1/2, z.
Acknowledgements top

AMI is grateful to the Director, NITK,Surathkal, India, for providing research facilities. Also SR thanks Dr Gautam Das, Syngene International Ltd, Bangalore, India, for allocation of research resources. The authors also thank the Universiti Sains Malaysia for Research University Golden Goose Grant No. 1001/PFIZIK/811012.

references
References top

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