organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoIUCrDATA
ISSN: 2414-3146

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

Edited by K. Fejfarova, Institute of Biotechnology CAS, Czech Republic (Received 3 October 2019; accepted 31 October 2019; online 12 November 2019)

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.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Imidazoles are heterocyclic compounds that show important pharmacological and biochemical properties including anti-fungal (Banfi, et al., 2006[Banfi, E., Scialino, G., Zampieri, D., Mamolo, M. G., Vio, L., Ferrone, M., Fermeglia, M., Paneni, M. S. & Pricl, S. (2006). J. Antimicrob. Chemother. 58, 76-84.]), anti-bacterial (Jackson et al., 2000[Jackson, C. J., Lamb, D. C., Kelly, D. E. & Kelly, S. L. (2000). FEMS Microbiol. Lett. 192, 159-162.]), anti-tumour (Dooley et al., 1992[Dooley, S. W., Jarvis, W. R., Martone, W. J. & Snider, D. E. (1992). Ann. Intern. Med. 117, 257-259.]; Cui et al., 2003[Cui, B., Zheng, B. L., He, K. & Zheng, Q. Y. (2003). J. Nat. Prod. 66, 1101-1103.]), anti-protozoal (Biftu et al., 2006[Biftu, T., Feng, D., Fisher, M., Liang, G. B., Qian, X., Scribner, A., Dennis, R., Lee, S., Liberator, P. A., Brown, C., Gurnett, A., Leavitt, P. S., Thompson, D., Mathew, J., Misura, A., Samaras, S., Tamas, T., Sina, J. F., McNulty, K. A., McKnight, C. G., Schmatz, D. M. & Wyvratt, M. (2006). Bioorg. Med. Chem. Lett. 16, 2479-2483.]), anti-herpes (Gudmundsson et al., 2007[Gudmundsson, K. S. & Johns, B. A. (2007). Bioorg. Med. Chem. Lett. 17, 2735-2739.]), anti-inflammatory (Rupert et al., 2003[Rupert, K. C., Henry, J. R., Dodd, J. H., Wadsworth, S. A., Cavender, D. E., Olini, G. C., Fahmy, B. & Siekierka, J. J. (2003). Bioorg. Med. Chem. Lett. 13, 347-350.]), anti-ulcerative, anti-hypertensive, anti-histaminic and anti-helminthic properties (Spasov et al., 1999[Spasov, A. A., Yozhitsa, I. N., Bugaeva, L. I. & Anisimova, V. A. (1999). Pharm. Chem. J. 33, 232-243.]). These compounds are highly active against human cytomegalovirus and varicella-zoster virus (Gueiffier et al.,1998[Gueiffier, A., Mavel, S., Lhassani, M., Elhakmaoui, A., Snoeck, R., Andrei, G., Chavignon, O., Teulade, J. C., Witvrouw, M., Balzarini, J., De Clercq, E. & Chapat, J. P. (1998). J. Med. Chem. 41, 5108-5112.]). In a continuation of our studies on imdiazole derivatives (Dhanalakshmi et al., 2018[Dhanalakshmi, G., Ramanjaneyulu, M., Thennarasu, S. & Aravindhan, S. (2018). Acta Cryst. E74, 1913-1918.]; Mala et al., 2019[Mala, R., Suman, K., Nandhagopal, M., Narayanasamy, M. & Thennarasu, S. (2019). Spectrochim. Acta A, 222, 117236.]), we herein report the synthesis and crystal structure analysis of the title compound.

The title compound (Fig. 1[link]) 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[link]) as shown in Fig. 2[link].

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3A⋯N2i 0.85 (2) 2.29 (2) 3.112 (3) 164 (2)
Symmetry code: (i) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].
[Figure 1]
Figure 1
Asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2]
Figure 2
Packing of the mol­ecules of the title compound. Hydrogen bonds are shown as blue lines.

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[Dhanalakshmi, G., Ramanjaneyulu, M., Thennarasu, S. & Aravindhan, S. (2018). Acta Cryst. E74, 1913-1918.]) 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 refinement are summarized in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula C17H18N4O2
Mr 310.35
Crystal system, space group Monoclinic, P21/c
Temperature (K) 296
a, b, c (Å) 8.046 (7), 11.038 (10), 17.912 (15)
β (°) 93.47 (3)
V3) 1588 (2)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.09
Crystal size (mm) 0.30 × 0.25 × 0.20
 
Data collection
Diffractometer Bruker Kappa APEX2 CMOS
Absorption correction Multi-scan (SADABS; Bruker, 2016[Bruker (2016). APEX3, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.678, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections 27960, 2770, 2430
Rint 0.026
(sin θ/λ)max−1) 0.595
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.133, 1.06
No. of reflections 2770
No. of parameters 212
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.20, −0.20
Computer programs: APEX3, SAINT and XPREP (Bruker, 2016[Bruker (2016). APEX3, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXT2014 (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2018 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]).

Structural data


Computing details top

Data collection: APEX3 (Bruker, 2016); cell refinement: 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).

N-(tert-Butyl)-2-(2-nitrophenyl)imidazo[1,2-a]pyridin-3-amine top
Crystal data top
C17H18N4O2F(000) = 656
Mr = 310.35Dx = 1.298 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 8.046 (7) ÅCell parameters from 9919 reflections
b = 11.038 (10) Åθ = 2.9–30.5°
c = 17.912 (15) ŵ = 0.09 mm1
β = 93.47 (3)°T = 296 K
V = 1588 (2) Å3Block, brown
Z = 40.30 × 0.25 × 0.20 mm
Data collection top
Bruker Kappa APEX2 CMOS
diffractometer
2770 independent reflections
Radiation source: fine-focus sealed tube2430 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
ω and φ scanθmax = 25.0°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2016)
h = 99
Tmin = 0.678, Tmax = 0.746k = 1313
27960 measured reflectionsl = 2120
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.048H 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 reflectionsΔρmax = 0.20 e Å3
212 parametersΔρmin = 0.20 e Å3
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.30330 (19)0.23121 (15)0.15414 (9)0.0301 (4)
C20.2519 (2)0.17506 (17)0.08591 (10)0.0379 (4)
H20.2749520.0936570.0780250.045*
C30.1687 (3)0.24088 (19)0.03207 (10)0.0459 (5)
H30.1331770.2041200.0128110.055*
C40.1353 (3)0.36484 (19)0.04332 (11)0.0486 (5)
H40.0776910.4088640.0058070.058*
C50.1860 (2)0.42014 (17)0.10783 (10)0.0394 (4)
H50.1647640.5020220.1149210.047*
C60.33523 (19)0.38898 (14)0.23310 (9)0.0279 (4)
C70.40432 (19)0.28449 (15)0.26309 (9)0.0299 (4)
C80.4982 (2)0.26944 (15)0.33571 (9)0.0326 (4)
C90.4610 (2)0.18049 (16)0.38715 (10)0.0387 (4)
C100.5537 (3)0.16271 (18)0.45377 (11)0.0493 (5)
H100.5247210.1024880.4868860.059*
C110.6900 (3)0.2359 (2)0.47024 (12)0.0534 (6)
H110.7539040.2255740.5148000.064*
C120.7309 (3)0.3245 (2)0.42035 (13)0.0535 (5)
H120.8231820.3734850.4313920.064*
C130.6367 (2)0.34146 (18)0.35419 (11)0.0425 (4)
H130.6662500.4020010.3213980.051*
C150.1893 (2)0.54261 (15)0.30802 (10)0.0355 (4)
C160.1656 (3)0.67880 (18)0.30153 (14)0.0581 (6)
H16A0.0830020.7044600.3346700.087*
H16B0.2690650.7188420.3148190.087*
H16C0.1295910.6991790.2510090.087*
C170.2453 (3)0.5097 (2)0.38823 (12)0.0607 (6)
H17A0.1602660.5321300.4209490.091*
H17B0.2645310.4239580.3916800.091*
H17C0.3463120.5521440.4025930.091*
C180.0280 (3)0.4774 (2)0.28534 (15)0.0605 (6)
H18A0.0554080.4988490.3191320.091*
H18B0.0088820.5006450.2354080.091*
H18C0.0461380.3914610.2871470.091*
N10.26936 (16)0.35359 (12)0.16279 (7)0.0289 (3)
N20.38504 (17)0.18709 (13)0.21493 (8)0.0334 (3)
N30.31833 (18)0.50905 (12)0.25542 (8)0.0315 (3)
N40.3144 (2)0.10426 (16)0.37388 (10)0.0530 (5)
O10.3307 (3)0.00446 (17)0.38458 (14)0.1032 (8)
O20.1814 (2)0.15316 (18)0.35684 (9)0.0685 (5)
H3A0.410 (3)0.544 (2)0.2658 (12)0.045 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0304 (8)0.0275 (8)0.0324 (9)0.0014 (6)0.0033 (6)0.0013 (7)
C20.0429 (10)0.0343 (9)0.0364 (9)0.0015 (7)0.0011 (8)0.0052 (7)
C30.0528 (11)0.0516 (12)0.0324 (9)0.0022 (9)0.0032 (8)0.0083 (8)
C40.0586 (12)0.0519 (12)0.0340 (10)0.0139 (10)0.0082 (8)0.0040 (8)
C50.0485 (10)0.0346 (9)0.0346 (9)0.0094 (8)0.0014 (8)0.0040 (7)
C60.0286 (8)0.0269 (8)0.0281 (8)0.0014 (6)0.0018 (6)0.0008 (6)
C70.0291 (8)0.0295 (9)0.0308 (8)0.0001 (6)0.0006 (6)0.0002 (6)
C80.0344 (8)0.0287 (8)0.0341 (9)0.0065 (7)0.0019 (7)0.0011 (7)
C90.0457 (10)0.0325 (9)0.0371 (9)0.0030 (8)0.0037 (8)0.0005 (7)
C100.0678 (13)0.0388 (10)0.0398 (10)0.0066 (9)0.0090 (9)0.0062 (8)
C110.0628 (13)0.0491 (12)0.0454 (11)0.0098 (10)0.0210 (10)0.0016 (9)
C120.0480 (11)0.0521 (12)0.0577 (13)0.0014 (9)0.0179 (10)0.0033 (10)
C130.0407 (10)0.0409 (10)0.0448 (11)0.0020 (8)0.0051 (8)0.0026 (8)
C150.0380 (9)0.0287 (9)0.0405 (10)0.0012 (7)0.0089 (7)0.0022 (7)
C160.0647 (14)0.0332 (11)0.0792 (16)0.0088 (9)0.0255 (12)0.0001 (10)
C170.0765 (16)0.0661 (15)0.0409 (11)0.0157 (12)0.0149 (11)0.0004 (10)
C180.0394 (11)0.0638 (14)0.0799 (16)0.0092 (10)0.0179 (11)0.0181 (12)
N10.0311 (7)0.0266 (7)0.0290 (7)0.0024 (5)0.0013 (5)0.0015 (5)
N20.0369 (8)0.0288 (7)0.0342 (8)0.0045 (6)0.0004 (6)0.0007 (6)
N30.0318 (8)0.0258 (7)0.0372 (8)0.0029 (6)0.0040 (6)0.0021 (6)
N40.0664 (12)0.0468 (11)0.0445 (10)0.0142 (9)0.0074 (8)0.0111 (8)
O10.1304 (19)0.0502 (11)0.1245 (19)0.0298 (11)0.0298 (15)0.0251 (11)
O20.0582 (10)0.0850 (13)0.0613 (10)0.0176 (9)0.0049 (8)0.0064 (9)
Geometric parameters (Å, º) top
C1—N21.330 (2)C11—C121.378 (3)
C1—N11.389 (2)C11—H110.9300
C1—C21.410 (3)C12—C131.380 (3)
C2—C31.352 (3)C12—H120.9300
C2—H20.9300C13—H130.9300
C3—C41.411 (3)C15—N31.490 (2)
C3—H30.9300C15—C181.518 (3)
C4—C51.348 (3)C15—C161.519 (3)
C4—H40.9300C15—C171.523 (3)
C5—N11.371 (2)C16—H16A0.9600
C5—H50.9300C16—H16B0.9600
C6—C71.375 (2)C16—H16C0.9600
C6—N11.392 (2)C17—H17A0.9600
C6—N31.393 (2)C17—H17B0.9600
C7—N21.381 (2)C17—H17C0.9600
C7—C81.473 (2)C18—H18A0.9600
C8—C91.391 (3)C18—H18B0.9600
C8—C131.392 (3)C18—H18C0.9600
C9—C101.382 (3)N3—H3A0.85 (2)
C9—N41.457 (3)N4—O21.221 (3)
C10—C111.380 (3)N4—O11.221 (3)
C10—H100.9300
N2—C1—N1110.84 (14)C12—C13—H13119.4
N2—C1—C2130.80 (16)C8—C13—H13119.4
N1—C1—C2118.36 (15)N3—C15—C18109.28 (16)
C3—C2—C1119.26 (18)N3—C15—C16106.68 (15)
C3—C2—H2120.4C18—C15—C16110.31 (18)
C1—C2—H2120.4N3—C15—C17111.07 (16)
C2—C3—C4120.63 (18)C18—C15—C17109.77 (18)
C2—C3—H3119.7C16—C15—C17109.69 (18)
C4—C3—H3119.7C15—C16—H16A109.5
C5—C4—C3120.74 (17)C15—C16—H16B109.5
C5—C4—H4119.6H16A—C16—H16B109.5
C3—C4—H4119.6C15—C16—H16C109.5
C4—C5—N1118.85 (18)H16A—C16—H16C109.5
C4—C5—H5120.6H16B—C16—H16C109.5
N1—C5—H5120.6C15—C17—H17A109.5
C7—C6—N1103.93 (14)C15—C17—H17B109.5
C7—C6—N3136.86 (16)H17A—C17—H17B109.5
N1—C6—N3119.21 (14)C15—C17—H17C109.5
C6—C7—N2112.41 (15)H17A—C17—H17C109.5
C6—C7—C8127.80 (15)H17B—C17—H17C109.5
N2—C7—C8119.72 (15)C15—C18—H18A109.5
C9—C8—C13116.53 (16)C15—C18—H18B109.5
C9—C8—C7123.01 (16)H18A—C18—H18B109.5
C13—C8—C7120.37 (16)C15—C18—H18C109.5
C10—C9—C8123.05 (18)H18A—C18—H18C109.5
C10—C9—N4116.62 (17)H18B—C18—H18C109.5
C8—C9—N4120.27 (16)C5—N1—C1122.15 (15)
C11—C10—C9118.80 (19)C5—N1—C6129.96 (15)
C11—C10—H10120.6C1—N1—C6107.89 (13)
C9—C10—H10120.6C1—N2—C7104.93 (14)
C12—C11—C10119.67 (18)C6—N3—C15120.11 (14)
C12—C11—H11120.2C6—N3—H3A113.4 (15)
C10—C11—H11120.2C15—N3—H3A112.5 (15)
C11—C12—C13120.8 (2)O2—N4—O1123.9 (2)
C11—C12—H12119.6O2—N4—C9118.32 (18)
C13—C12—H12119.6O1—N4—C9117.6 (2)
C12—C13—C8121.11 (19)
N2—C1—C2—C3179.80 (18)C4—C5—N1—C10.0 (3)
N1—C1—C2—C31.4 (2)C4—C5—N1—C6179.30 (17)
C1—C2—C3—C40.8 (3)N2—C1—N1—C5179.99 (15)
C2—C3—C4—C50.2 (3)C2—C1—N1—C51.0 (2)
C3—C4—C5—N10.6 (3)N2—C1—N1—C60.59 (18)
N1—C6—C7—N20.24 (18)C2—C1—N1—C6178.43 (14)
N3—C6—C7—N2179.97 (17)C7—C6—N1—C5179.84 (16)
N1—C6—C7—C8177.11 (15)N3—C6—N1—C50.3 (2)
N3—C6—C7—C83.1 (3)C7—C6—N1—C10.49 (16)
C6—C7—C8—C9129.2 (2)N3—C6—N1—C1179.68 (14)
N2—C7—C8—C954.2 (2)N1—C1—N2—C70.43 (17)
C6—C7—C8—C1354.4 (3)C2—C1—N2—C7178.44 (17)
N2—C7—C8—C13122.28 (19)C6—C7—N2—C10.11 (18)
C13—C8—C9—C100.4 (3)C8—C7—N2—C1177.04 (14)
C7—C8—C9—C10176.93 (17)C7—C6—N3—C1577.9 (3)
C13—C8—C9—N4177.47 (17)N1—C6—N3—C15101.86 (18)
C7—C8—C9—N45.9 (3)C18—C15—N3—C643.1 (2)
C8—C9—C10—C110.3 (3)C16—C15—N3—C6162.30 (17)
N4—C9—C10—C11177.48 (19)C17—C15—N3—C678.2 (2)
C9—C10—C11—C120.1 (3)C10—C9—N4—O2128.0 (2)
C10—C11—C12—C130.4 (3)C8—C9—N4—O249.3 (3)
C11—C12—C13—C80.3 (3)C10—C9—N4—O148.0 (3)
C9—C8—C13—C120.1 (3)C8—C9—N4—O1134.7 (2)
C7—C8—C13—C12176.75 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···N2i0.85 (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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