organic compounds
N-(tert-Butyl)-2-(2-nitrophenyl)imidazo[1,2-a]pyridin-3-amine
aDepartment of Physics, Presidency College(Autonomous), University of Madras, Chennai, Tamilnadu, India, and bOrganic & Bioorganic Chemistry Laboratory, Academy of Scientific and Innovative Research (AcSIR), CSIR-Central Leather Research Institute Adyar, Chennai, India
*Correspondence e-mail: aravindhanpresidency@gmail.com
In the title compound, C17H18N4O2, the dihedral angle between the pyridine and benzene rings is 55.68 (11)°. In the crystal, N—H⋯N hydrogen bonds link the molecules into [010] chains.
Structure description
Imidazoles are et al., 2006), anti-bacterial (Jackson et al., 2000), anti-tumour (Dooley et al., 1992; Cui et al., 2003), anti-protozoal (Biftu et al., 2006), anti-herpes (Gudmundsson et al., 2007), anti-inflammatory (Rupert et al., 2003), anti-ulcerative, anti-hypertensive, anti-histaminic and anti-helminthic properties (Spasov et al., 1999). These compounds are highly active against human cytomegalovirus and varicella-zoster virus (Gueiffier et al.,1998). In a continuation of our studies on imdiazole derivatives (Dhanalakshmi et al., 2018; Mala et al., 2019), we herein report the synthesis and analysis of the title compound.
that show important pharmacological and biochemical properties including anti-fungal (Banfi,The title compound (Fig. 1) consists of imidazole, pyridine and benzene rings with a nitro group connected at the C9 position of the benzene ring and an N-bonded tert-butyl group (N3/C15–C18) connected at C6 of the imidazole ring. The pyridine ring (C1–C5/N1) is fused to the imidazole ring at a dihedral angle of 0.76 (9)°. The dihedral angle between the pyridine and benzene rings is 55.68 (11)°. The dihedral angle between the NO2 group (N4/O1/O2) and the benzene ring is 49 (3)°. In the crystal, molecules are linked by N3—H3A⋯N2 hydrogen bonds (Table 1) as shown in Fig. 2.
Synthesis and crystallization
N-(tert-Butyl)-2-(2-nitrophenyl)imidazo[1,2-a]pyridin-3-amine was prepared by our reported method (reagent quantities: 1 eq. of tert-butyl isocyanide and 0.5 mmol of iodine; Dhanalakshmi et al., 2018) and confirmed by NMR, ESI–MS and IR spectroscopy. 1H NMR (400 MHz, CDCl3) δ = 8.19 (d, J = 6.9, 1H), 7.91 (dd, J = 8.1, 0.9, 1H), 7.80 (d, J = 1.2, 1H), 7.65 (d, J = 1.1, 1H), 7.51 (dd, J = 16.4, 4.9, 2H), 7.16 (ddd, J = 9.0, 6.7, 1.2, 1H), 6.81 (d, J = 0.9, 1H), 0.95 (s, 9H). 13C NMR (101 MHz, CDCl3) δ 149.51, 147.62, 142.42, 137.93, 136.20, 132.85, 132.39, 130.30, 128.38, 124.69, 124.37, 124.25, 123.33, 117.72, 113.94, 111.77, 108.78, 55.60, 30.05. Chemical formula: C17H18N4O2 expected or exact mass 310.1430. Obtained mass: 3110.20 m/z.
Refinement
Crystal data, data collection and structure .
are summarized in Table 2Structural data
https://doi.org/10.1107/S2414314619014779/ff4031sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314619014779/ff4031Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314619014779/ff4031Isup3.cml
Data collection: APEX3 (Bruker, 2016); cell
APEX3 and SAINT (Bruker, 2016); data reduction: SAINT and XPREP (Bruker, 2016); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2018 (Sheldrick, 2015b).C17H18N4O2 | F(000) = 656 |
Mr = 310.35 | Dx = 1.298 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 8.046 (7) Å | Cell parameters from 9919 reflections |
b = 11.038 (10) Å | θ = 2.9–30.5° |
c = 17.912 (15) Å | µ = 0.09 mm−1 |
β = 93.47 (3)° | T = 296 K |
V = 1588 (2) Å3 | Block, brown |
Z = 4 | 0.30 × 0.25 × 0.20 mm |
Bruker Kappa APEX2 CMOS diffractometer | 2770 independent reflections |
Radiation source: fine-focus sealed tube | 2430 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.026 |
ω and φ scan | θmax = 25.0°, θmin = 2.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2016) | h = −9→9 |
Tmin = 0.678, Tmax = 0.746 | k = −13→13 |
27960 measured reflections | l = −21→20 |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.048 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.133 | w = 1/[σ2(Fo2) + (0.061P)2 + 0.9086P] where P = (Fo2 + 2Fc2)/3 |
S = 1.06 | (Δ/σ)max < 0.001 |
2770 reflections | Δρmax = 0.20 e Å−3 |
212 parameters | Δρmin = −0.20 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.30330 (19) | 0.23121 (15) | 0.15414 (9) | 0.0301 (4) | |
C2 | 0.2519 (2) | 0.17506 (17) | 0.08591 (10) | 0.0379 (4) | |
H2 | 0.274952 | 0.093657 | 0.078025 | 0.045* | |
C3 | 0.1687 (3) | 0.24088 (19) | 0.03207 (10) | 0.0459 (5) | |
H3 | 0.133177 | 0.204120 | −0.012811 | 0.055* | |
C4 | 0.1353 (3) | 0.36484 (19) | 0.04332 (11) | 0.0486 (5) | |
H4 | 0.077691 | 0.408864 | 0.005807 | 0.058* | |
C5 | 0.1860 (2) | 0.42014 (17) | 0.10783 (10) | 0.0394 (4) | |
H5 | 0.164764 | 0.502022 | 0.114921 | 0.047* | |
C6 | 0.33523 (19) | 0.38898 (14) | 0.23310 (9) | 0.0279 (4) | |
C7 | 0.40432 (19) | 0.28449 (15) | 0.26309 (9) | 0.0299 (4) | |
C8 | 0.4982 (2) | 0.26944 (15) | 0.33571 (9) | 0.0326 (4) | |
C9 | 0.4610 (2) | 0.18049 (16) | 0.38715 (10) | 0.0387 (4) | |
C10 | 0.5537 (3) | 0.16271 (18) | 0.45377 (11) | 0.0493 (5) | |
H10 | 0.524721 | 0.102488 | 0.486886 | 0.059* | |
C11 | 0.6900 (3) | 0.2359 (2) | 0.47024 (12) | 0.0534 (6) | |
H11 | 0.753904 | 0.225574 | 0.514800 | 0.064* | |
C12 | 0.7309 (3) | 0.3245 (2) | 0.42035 (13) | 0.0535 (5) | |
H12 | 0.823182 | 0.373485 | 0.431392 | 0.064* | |
C13 | 0.6367 (2) | 0.34146 (18) | 0.35419 (11) | 0.0425 (4) | |
H13 | 0.666250 | 0.402001 | 0.321398 | 0.051* | |
C15 | 0.1893 (2) | 0.54261 (15) | 0.30802 (10) | 0.0355 (4) | |
C16 | 0.1656 (3) | 0.67880 (18) | 0.30153 (14) | 0.0581 (6) | |
H16A | 0.083002 | 0.704460 | 0.334670 | 0.087* | |
H16B | 0.269065 | 0.718842 | 0.314819 | 0.087* | |
H16C | 0.129591 | 0.699179 | 0.251009 | 0.087* | |
C17 | 0.2453 (3) | 0.5097 (2) | 0.38823 (12) | 0.0607 (6) | |
H17A | 0.160266 | 0.532130 | 0.420949 | 0.091* | |
H17B | 0.264531 | 0.423958 | 0.391680 | 0.091* | |
H17C | 0.346312 | 0.552144 | 0.402593 | 0.091* | |
C18 | 0.0280 (3) | 0.4774 (2) | 0.28534 (15) | 0.0605 (6) | |
H18A | −0.055408 | 0.498849 | 0.319132 | 0.091* | |
H18B | −0.008882 | 0.500645 | 0.235408 | 0.091* | |
H18C | 0.046138 | 0.391461 | 0.287147 | 0.091* | |
N1 | 0.26936 (16) | 0.35359 (12) | 0.16279 (7) | 0.0289 (3) | |
N2 | 0.38504 (17) | 0.18709 (13) | 0.21493 (8) | 0.0334 (3) | |
N3 | 0.31833 (18) | 0.50905 (12) | 0.25542 (8) | 0.0315 (3) | |
N4 | 0.3144 (2) | 0.10426 (16) | 0.37388 (10) | 0.0530 (5) | |
O1 | 0.3307 (3) | −0.00446 (17) | 0.38458 (14) | 0.1032 (8) | |
O2 | 0.1814 (2) | 0.15316 (18) | 0.35684 (9) | 0.0685 (5) | |
H3A | 0.410 (3) | 0.544 (2) | 0.2658 (12) | 0.045 (6)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0304 (8) | 0.0275 (8) | 0.0324 (9) | 0.0014 (6) | 0.0033 (6) | −0.0013 (7) |
C2 | 0.0429 (10) | 0.0343 (9) | 0.0364 (9) | 0.0015 (7) | 0.0011 (8) | −0.0052 (7) |
C3 | 0.0528 (11) | 0.0516 (12) | 0.0324 (9) | 0.0022 (9) | −0.0032 (8) | −0.0083 (8) |
C4 | 0.0586 (12) | 0.0519 (12) | 0.0340 (10) | 0.0139 (10) | −0.0082 (8) | 0.0040 (8) |
C5 | 0.0485 (10) | 0.0346 (9) | 0.0346 (9) | 0.0094 (8) | −0.0014 (8) | 0.0040 (7) |
C6 | 0.0286 (8) | 0.0269 (8) | 0.0281 (8) | −0.0014 (6) | 0.0018 (6) | 0.0008 (6) |
C7 | 0.0291 (8) | 0.0295 (9) | 0.0308 (8) | −0.0001 (6) | 0.0006 (6) | 0.0002 (6) |
C8 | 0.0344 (8) | 0.0287 (8) | 0.0341 (9) | 0.0065 (7) | −0.0019 (7) | −0.0011 (7) |
C9 | 0.0457 (10) | 0.0325 (9) | 0.0371 (9) | 0.0030 (8) | −0.0037 (8) | 0.0005 (7) |
C10 | 0.0678 (13) | 0.0388 (10) | 0.0398 (10) | 0.0066 (9) | −0.0090 (9) | 0.0062 (8) |
C11 | 0.0628 (13) | 0.0491 (12) | 0.0454 (11) | 0.0098 (10) | −0.0210 (10) | −0.0016 (9) |
C12 | 0.0480 (11) | 0.0521 (12) | 0.0577 (13) | −0.0014 (9) | −0.0179 (10) | −0.0033 (10) |
C13 | 0.0407 (10) | 0.0409 (10) | 0.0448 (11) | −0.0020 (8) | −0.0051 (8) | 0.0026 (8) |
C15 | 0.0380 (9) | 0.0287 (9) | 0.0405 (10) | 0.0012 (7) | 0.0089 (7) | −0.0022 (7) |
C16 | 0.0647 (14) | 0.0332 (11) | 0.0792 (16) | 0.0088 (9) | 0.0255 (12) | −0.0001 (10) |
C17 | 0.0765 (16) | 0.0661 (15) | 0.0409 (11) | 0.0157 (12) | 0.0149 (11) | −0.0004 (10) |
C18 | 0.0394 (11) | 0.0638 (14) | 0.0799 (16) | −0.0092 (10) | 0.0179 (11) | −0.0181 (12) |
N1 | 0.0311 (7) | 0.0266 (7) | 0.0290 (7) | 0.0024 (5) | 0.0013 (5) | 0.0015 (5) |
N2 | 0.0369 (8) | 0.0288 (7) | 0.0342 (8) | 0.0045 (6) | −0.0004 (6) | −0.0007 (6) |
N3 | 0.0318 (8) | 0.0258 (7) | 0.0372 (8) | −0.0029 (6) | 0.0040 (6) | −0.0021 (6) |
N4 | 0.0664 (12) | 0.0468 (11) | 0.0445 (10) | −0.0142 (9) | −0.0074 (8) | 0.0111 (8) |
O1 | 0.1304 (19) | 0.0502 (11) | 0.1245 (19) | −0.0298 (11) | −0.0298 (15) | 0.0251 (11) |
O2 | 0.0582 (10) | 0.0850 (13) | 0.0613 (10) | −0.0176 (9) | −0.0049 (8) | 0.0064 (9) |
C1—N2 | 1.330 (2) | C11—C12 | 1.378 (3) |
C1—N1 | 1.389 (2) | C11—H11 | 0.9300 |
C1—C2 | 1.410 (3) | C12—C13 | 1.380 (3) |
C2—C3 | 1.352 (3) | C12—H12 | 0.9300 |
C2—H2 | 0.9300 | C13—H13 | 0.9300 |
C3—C4 | 1.411 (3) | C15—N3 | 1.490 (2) |
C3—H3 | 0.9300 | C15—C18 | 1.518 (3) |
C4—C5 | 1.348 (3) | C15—C16 | 1.519 (3) |
C4—H4 | 0.9300 | C15—C17 | 1.523 (3) |
C5—N1 | 1.371 (2) | C16—H16A | 0.9600 |
C5—H5 | 0.9300 | C16—H16B | 0.9600 |
C6—C7 | 1.375 (2) | C16—H16C | 0.9600 |
C6—N1 | 1.392 (2) | C17—H17A | 0.9600 |
C6—N3 | 1.393 (2) | C17—H17B | 0.9600 |
C7—N2 | 1.381 (2) | C17—H17C | 0.9600 |
C7—C8 | 1.473 (2) | C18—H18A | 0.9600 |
C8—C9 | 1.391 (3) | C18—H18B | 0.9600 |
C8—C13 | 1.392 (3) | C18—H18C | 0.9600 |
C9—C10 | 1.382 (3) | N3—H3A | 0.85 (2) |
C9—N4 | 1.457 (3) | N4—O2 | 1.221 (3) |
C10—C11 | 1.380 (3) | N4—O1 | 1.221 (3) |
C10—H10 | 0.9300 | ||
N2—C1—N1 | 110.84 (14) | C12—C13—H13 | 119.4 |
N2—C1—C2 | 130.80 (16) | C8—C13—H13 | 119.4 |
N1—C1—C2 | 118.36 (15) | N3—C15—C18 | 109.28 (16) |
C3—C2—C1 | 119.26 (18) | N3—C15—C16 | 106.68 (15) |
C3—C2—H2 | 120.4 | C18—C15—C16 | 110.31 (18) |
C1—C2—H2 | 120.4 | N3—C15—C17 | 111.07 (16) |
C2—C3—C4 | 120.63 (18) | C18—C15—C17 | 109.77 (18) |
C2—C3—H3 | 119.7 | C16—C15—C17 | 109.69 (18) |
C4—C3—H3 | 119.7 | C15—C16—H16A | 109.5 |
C5—C4—C3 | 120.74 (17) | C15—C16—H16B | 109.5 |
C5—C4—H4 | 119.6 | H16A—C16—H16B | 109.5 |
C3—C4—H4 | 119.6 | C15—C16—H16C | 109.5 |
C4—C5—N1 | 118.85 (18) | H16A—C16—H16C | 109.5 |
C4—C5—H5 | 120.6 | H16B—C16—H16C | 109.5 |
N1—C5—H5 | 120.6 | C15—C17—H17A | 109.5 |
C7—C6—N1 | 103.93 (14) | C15—C17—H17B | 109.5 |
C7—C6—N3 | 136.86 (16) | H17A—C17—H17B | 109.5 |
N1—C6—N3 | 119.21 (14) | C15—C17—H17C | 109.5 |
C6—C7—N2 | 112.41 (15) | H17A—C17—H17C | 109.5 |
C6—C7—C8 | 127.80 (15) | H17B—C17—H17C | 109.5 |
N2—C7—C8 | 119.72 (15) | C15—C18—H18A | 109.5 |
C9—C8—C13 | 116.53 (16) | C15—C18—H18B | 109.5 |
C9—C8—C7 | 123.01 (16) | H18A—C18—H18B | 109.5 |
C13—C8—C7 | 120.37 (16) | C15—C18—H18C | 109.5 |
C10—C9—C8 | 123.05 (18) | H18A—C18—H18C | 109.5 |
C10—C9—N4 | 116.62 (17) | H18B—C18—H18C | 109.5 |
C8—C9—N4 | 120.27 (16) | C5—N1—C1 | 122.15 (15) |
C11—C10—C9 | 118.80 (19) | C5—N1—C6 | 129.96 (15) |
C11—C10—H10 | 120.6 | C1—N1—C6 | 107.89 (13) |
C9—C10—H10 | 120.6 | C1—N2—C7 | 104.93 (14) |
C12—C11—C10 | 119.67 (18) | C6—N3—C15 | 120.11 (14) |
C12—C11—H11 | 120.2 | C6—N3—H3A | 113.4 (15) |
C10—C11—H11 | 120.2 | C15—N3—H3A | 112.5 (15) |
C11—C12—C13 | 120.8 (2) | O2—N4—O1 | 123.9 (2) |
C11—C12—H12 | 119.6 | O2—N4—C9 | 118.32 (18) |
C13—C12—H12 | 119.6 | O1—N4—C9 | 117.6 (2) |
C12—C13—C8 | 121.11 (19) | ||
N2—C1—C2—C3 | 179.80 (18) | C4—C5—N1—C1 | 0.0 (3) |
N1—C1—C2—C3 | −1.4 (2) | C4—C5—N1—C6 | 179.30 (17) |
C1—C2—C3—C4 | 0.8 (3) | N2—C1—N1—C5 | −179.99 (15) |
C2—C3—C4—C5 | 0.2 (3) | C2—C1—N1—C5 | 1.0 (2) |
C3—C4—C5—N1 | −0.6 (3) | N2—C1—N1—C6 | 0.59 (18) |
N1—C6—C7—N2 | 0.24 (18) | C2—C1—N1—C6 | −178.43 (14) |
N3—C6—C7—N2 | −179.97 (17) | C7—C6—N1—C5 | −179.84 (16) |
N1—C6—C7—C8 | 177.11 (15) | N3—C6—N1—C5 | 0.3 (2) |
N3—C6—C7—C8 | −3.1 (3) | C7—C6—N1—C1 | −0.49 (16) |
C6—C7—C8—C9 | 129.2 (2) | N3—C6—N1—C1 | 179.68 (14) |
N2—C7—C8—C9 | −54.2 (2) | N1—C1—N2—C7 | −0.43 (17) |
C6—C7—C8—C13 | −54.4 (3) | C2—C1—N2—C7 | 178.44 (17) |
N2—C7—C8—C13 | 122.28 (19) | C6—C7—N2—C1 | 0.11 (18) |
C13—C8—C9—C10 | 0.4 (3) | C8—C7—N2—C1 | −177.04 (14) |
C7—C8—C9—C10 | 176.93 (17) | C7—C6—N3—C15 | −77.9 (3) |
C13—C8—C9—N4 | 177.47 (17) | N1—C6—N3—C15 | 101.86 (18) |
C7—C8—C9—N4 | −5.9 (3) | C18—C15—N3—C6 | −43.1 (2) |
C8—C9—C10—C11 | −0.3 (3) | C16—C15—N3—C6 | −162.30 (17) |
N4—C9—C10—C11 | −177.48 (19) | C17—C15—N3—C6 | 78.2 (2) |
C9—C10—C11—C12 | −0.1 (3) | C10—C9—N4—O2 | 128.0 (2) |
C10—C11—C12—C13 | 0.4 (3) | C8—C9—N4—O2 | −49.3 (3) |
C11—C12—C13—C8 | −0.3 (3) | C10—C9—N4—O1 | −48.0 (3) |
C9—C8—C13—C12 | −0.1 (3) | C8—C9—N4—O1 | 134.7 (2) |
C7—C8—C13—C12 | −176.75 (18) |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···N2i | 0.85 (2) | 2.29 (2) | 3.112 (3) | 164 (2) |
Symmetry code: (i) −x+1, y+1/2, −z+1/2. |
Acknowledgements
The authors thank the SAIF, IIT, Madras for the data collection.
References
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