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

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ISSN: 2056-9890

tert-Butyl 4-(3,4-di­chloro­anilino)piperidine-1-carboxyl­ate

aInstitute of Chemistry, University of The Punjab, Qaid-i-Azam Campus, Lahore 54590, Pakistan, and bDepartment of Chemistry and Biochemistry, 1306 E University Boulevard, The University of Arizona, Tucson, AZ 85721, USA
*Correspondence e-mail: suer@email.arizona.edu

(Received 20 December 2012; accepted 26 December 2012; online 9 January 2013)

In the title compound, C16H22Cl2N2O2, the substituted piperidine ring adopts a chair conformation with both substituents in equatorial positions. In the crystal, N—H⋯O and C—H⋯O hydrogen bonds connect mol­ecules into ribbons along the a-axis direction.

Related literature

For the biological activity of piperazine derivatives, see: Hamed et al. (2012[Hamed, A., Christoph, B., Olivier, C., Bibia, H. & Romain, S. (2012). US Patent Appl. 2012316178.]); Joergen et al. (1997[Joergen, S.-K., Peter, M. & Frank, W. (1997). World Patent WO9730997.]); Peter et al. (2009[Peter, D., Eriksen, B. L., Munro, G. & Nielsen, E. (2009). World Patent WO 2009/077585.]). For the synthesis of the title compound, see: Vardanyan et al. (2009[Vardanyan, R., Vijay, G., Nichol, G. S., Liu, L., Kumarasinghe, I., Davis, P., Vanderah, T., Porreca, F., Lai, J. & Hruby, V. J. (2009). Bioorg. Med. Chem. 14, 5044-5053.]).

[Scheme 1]

Experimental

Crystal data
  • C16H22Cl2N2O2

  • Mr = 345.25

  • Orthorhombic, P 21 21 21

  • a = 9.7825 (6) Å

  • b = 10.6075 (6) Å

  • c = 16.8215 (10) Å

  • V = 1745.53 (18) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.38 mm−1

  • T = 100 K

  • 0.40 × 0.40 × 0.30 mm

Data collection
  • Bruker Kappa APEXII DUO CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.662, Tmax = 0.749

  • 34136 measured reflections

  • 13197 independent reflections

  • 11079 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.079

  • S = 1.00

  • 13197 reflections

  • 202 parameters

  • H-atom parameters constrained

  • Δρmax = 0.44 e Å−3

  • Δρmin = −0.19 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 6110 Friedel pairs

  • Flack parameter: −0.01 (2)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O2i 0.88 2.12 2.9740 (8) 163
C3—H3⋯O2i 0.95 2.58 3.3486 (9) 138
Symmetry code: (i) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Piperazine derivatives have been shown to inhibit re-uptake of the monoamines dopamine, noradrenaline and serotonin in synaptosomes (Joergen et al., 1997), and their use for the treatment of protozoal infections, particularly malaria, has also been reported (Hamed et al., 2012). Selective serotonin reuptake inhibitors (SSRI) provide efficacy in the treatment of numerous CNS disorders, including depression and panic disorders, and are usually observed to be effective, well tolerated and simply administered (Peter et al., 2009)). During our search to find new synthetic novel multivalent ligands for the treatment of pain and depression, the title compound was synthesized as an intermediate. Compounds prepared from this intermediate are now under study for possible opioid and SSRIs activities.

The piperidine ring is in a chair conformation with both substituents in equatorial positions. An intermolecular hydrogen bond is present between N1—H1 and O2 with a donor-hydrogen-acceptor angle of 163.40° and a donor-aceptor distance of 2.9740 (8) Å. Hydrogen bonds connect molecules into ribbons extending in the crystallographic a direction. The hydrogen bonding graph set is C1,1(8)a.

Related literature top

For the biological activity of piperazine derivatives, see: Hamed et al. (2012); Joergen et al. (1997); Peter et al. (2009). For the synthesis of the title compound, see: Vardanyan et al. (2009).

Experimental top

tert-Butyl 4-((3,4-dichlorophenyl)amino)piperidine-1-carboxylate (1) was synthesized by modification of a reported method (Vardanyan et al., 2009) by refluxing N-Boc-4-piperidone (5.0 g, 25.1 mmol) and 3,4-dichloroaniline (4.07 g, 25.1 mmol) in toluene (100 ml) with a catalytic amount of p-toluene sulphonic acid using a Dean and Stark apparatus for 4–5 h. The reaction was left to cool overnight. Toluene was evaporated under reduced pressure. The crude product was dissolved in diethyl ether, passed through a bed of neutral alumina, and the ether evaporated under reduced pressure. The residue was dissolved in CH3OH (50 ml) and NaBH4 (1.05 g, 27.6 mmol) was added slowly at room temperature. The reaction mixture was left to stir overnight. The reaction was quenched with aqueous NaHCO3 (5 ml). The solvent was removed under reduced pressure and the residue was dissolved in diethyl ether, dried over anhydrous MgSO4, filtered and evaporated under reduced pressure. The residue was recrystallized from CH3OH to obtain (1) as a white crystalline solid. Crystals appropriate for X-ray diffraction were grown from methanol by slow evaporation at room temperature. 8.22 g (95%) yield; m.p. 155–157 °C; MS (ESI): m/z: [M+H]+: 345; HRMS: Calcd for C16H23Cl2N2O2: 345.113; found: 345.1131.

Refinement top

All hydrogen atoms were visible in a difference Fourier map and were added at calculated positions. Bond distances are set to 0.95 Å for carbon-hydrogen bonds, and 0.88 Å for nitrogen-hydrogen bonds. Thermal parameters for hydrogen atoms were set to 1.2 times the isotropic equivalent thermal parameter of the atom to which the hydrogen atom is bonded.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound. Anisotropically refined atoms are shown as 50% probability ellipsoids.
[Figure 2] Fig. 2. Hydrogen bonding interactions, shown as dashed lines. The molecules are connected into a chain running along the a direction in the crystal.
tert-Butyl 4-(3,4-dichloroanilino)piperidine-1-carboxylate top
Crystal data top
C16H22Cl2N2O2Dx = 1.302 Mg m3
Mr = 345.25Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121Cell parameters from 9939 reflections
a = 9.7825 (6) Åθ = 2.8–40.0°
b = 10.6075 (6) ŵ = 0.38 mm1
c = 16.8215 (10) ÅT = 100 K
V = 1745.53 (18) Å3Rod, clear colourless
Z = 40.40 × 0.40 × 0.30 mm
F(000) = 728
Data collection top
Bruker Kappa APEXII DUO CCD
diffractometer
13197 independent reflections
Radiation source: fine-focus sealed tube11079 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
Detector resolution: 8.3333 pixels mm-1θmax = 43.7°, θmin = 2.3°
ϕ and ω scansh = 1917
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
k = 2015
Tmin = 0.662, Tmax = 0.749l = 3222
34136 measured reflections
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)] = 0.034H-atom parameters constrained
wR(F2) = 0.079 w = 1/[σ2(Fo2) + (0.0361P)2 + 0.1129P]
where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max = 0.002
13197 reflectionsΔρmax = 0.44 e Å3
202 parametersΔρmin = 0.19 e Å3
0 restraintsAbsolute structure: Flack (1983), ???? Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.01 (2)
Crystal data top
C16H22Cl2N2O2V = 1745.53 (18) Å3
Mr = 345.25Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 9.7825 (6) ŵ = 0.38 mm1
b = 10.6075 (6) ÅT = 100 K
c = 16.8215 (10) Å0.40 × 0.40 × 0.30 mm
Data collection top
Bruker Kappa APEXII DUO CCD
diffractometer
13197 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
11079 reflections with I > 2σ(I)
Tmin = 0.662, Tmax = 0.749Rint = 0.024
34136 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.034H-atom parameters constrained
wR(F2) = 0.079Δρmax = 0.44 e Å3
S = 1.00Δρmin = 0.19 e Å3
13197 reflectionsAbsolute structure: Flack (1983), ???? Friedel pairs
202 parametersAbsolute structure parameter: 0.01 (2)
0 restraints
Special details top

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
Cl10.08164 (2)0.97197 (2)0.972015 (11)0.02294 (4)
Cl20.13863 (19)0.75577 (18)0.941766 (10)0.01982 (3)
O10.10534 (5)0.83348 (5)0.29230 (3)0.01589 (9)
O20.11737 (5)0.79311 (6)0.32343 (3)0.01988 (10)
C140.06777 (12)0.63102 (8)0.22473 (6)0.03006 (19)
H14A0.12760.5950.26550.045*
H14B0.08220.58670.17430.045*
H14C0.02780.62170.24120.045*
C30.13364 (7)0.82954 (6)0.78917 (4)0.01425 (10)
H30.20060.76580.78150.017*
C130.10078 (8)0.77016 (7)0.21416 (4)0.01681 (11)
C120.00406 (7)0.83543 (6)0.34047 (4)0.01344 (10)
N20.02566 (6)0.89021 (6)0.41112 (4)0.01450 (9)
C100.15552 (7)0.95171 (7)0.43015 (4)0.01648 (11)
H10A0.14331.04440.42960.02*
H10B0.22470.92950.38950.02*
C110.20526 (7)0.90986 (8)0.51199 (4)0.01733 (12)
H11A0.28810.95850.52630.021*
H11B0.23060.81960.50990.021*
C70.09632 (7)0.92909 (7)0.57613 (4)0.01480 (10)
H70.07841.02150.58160.018*
N10.14933 (7)0.88223 (7)0.65131 (4)0.01898 (11)
H10.22550.83810.65020.023*
C40.08893 (7)0.90197 (6)0.72395 (4)0.01433 (10)
C50.01262 (8)0.99380 (7)0.73731 (4)0.01686 (12)
H50.04681.04170.69390.02*
C60.06310 (7)1.01490 (7)0.81332 (4)0.01730 (11)
H60.13031.07830.82150.021*
C10.01660 (7)0.94440 (7)0.87772 (4)0.01538 (11)
C20.08092 (7)0.85036 (6)0.86435 (4)0.01397 (10)
C90.08241 (7)0.91113 (7)0.46944 (4)0.01573 (10)
H9A0.16620.86590.45280.019*
H9B0.10391.00220.47240.019*
C80.03699 (7)0.86400 (7)0.55099 (4)0.01653 (11)
H8A0.02280.77160.5490.02*
H8B0.10920.88180.59060.02*
C160.24662 (8)0.78782 (8)0.18424 (5)0.02256 (14)
H16A0.26880.87790.18320.034*
H16B0.25470.7530.13050.034*
H16C0.31010.74390.21980.034*
C150.00084 (9)0.83714 (10)0.15914 (5)0.02569 (16)
H15A0.09080.83520.18260.039*
H15B0.00070.79440.10750.039*
H15C0.02970.92490.15190.039*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.01965 (7)0.03505 (10)0.01412 (7)0.00661 (7)0.00311 (6)0.00055 (6)
Cl20.02267 (7)0.02154 (7)0.01526 (6)0.00232 (6)0.00074 (6)0.00598 (6)
O10.0154 (2)0.0189 (2)0.01340 (19)0.00364 (16)0.00210 (15)0.00379 (17)
O20.0162 (2)0.0272 (3)0.0163 (2)0.00867 (19)0.00053 (17)0.00255 (19)
C140.0419 (5)0.0163 (3)0.0320 (4)0.0073 (3)0.0078 (4)0.0062 (3)
C30.0142 (2)0.0149 (2)0.0137 (2)0.0010 (2)0.0004 (2)0.0009 (2)
C130.0203 (3)0.0166 (3)0.0135 (2)0.0034 (2)0.0022 (2)0.0035 (2)
C120.0144 (2)0.0139 (2)0.0120 (2)0.0024 (2)0.00017 (19)0.00076 (19)
N20.0122 (2)0.0189 (2)0.0124 (2)0.00349 (18)0.00084 (17)0.00202 (18)
C100.0145 (2)0.0219 (3)0.0131 (2)0.0061 (2)0.0004 (2)0.0001 (2)
C110.0132 (2)0.0253 (3)0.0135 (3)0.0000 (2)0.0002 (2)0.0005 (2)
C70.0151 (2)0.0174 (3)0.0119 (2)0.0014 (2)0.00057 (19)0.0005 (2)
N10.0201 (3)0.0252 (3)0.0116 (2)0.0098 (2)0.0005 (2)0.0014 (2)
C40.0145 (2)0.0160 (2)0.0124 (2)0.0019 (2)0.0001 (2)0.00067 (19)
C50.0173 (3)0.0190 (3)0.0142 (3)0.0052 (2)0.0003 (2)0.0022 (2)
C60.0166 (3)0.0199 (3)0.0155 (3)0.0044 (2)0.0011 (2)0.0010 (2)
C10.0140 (2)0.0188 (3)0.0133 (2)0.0005 (2)0.0013 (2)0.0004 (2)
C20.0135 (2)0.0150 (2)0.0134 (2)0.0005 (2)0.0013 (2)0.00250 (19)
C90.0132 (2)0.0197 (3)0.0143 (2)0.0003 (2)0.0008 (2)0.0017 (2)
C80.0159 (3)0.0197 (3)0.0140 (3)0.0014 (2)0.0024 (2)0.0007 (2)
C160.0219 (3)0.0250 (3)0.0208 (3)0.0014 (3)0.0062 (3)0.0042 (3)
C150.0246 (3)0.0378 (4)0.0147 (3)0.0000 (3)0.0006 (3)0.0007 (3)
Geometric parameters (Å, º) top
Cl1—C11.7338 (7)C7—N11.4544 (9)
Cl2—C21.7382 (7)C7—C81.5350 (10)
O1—C121.3425 (8)C7—H71.0
O1—C131.4767 (8)N1—C41.3734 (9)
O2—C121.2298 (8)N1—H10.88
C14—C131.5213 (11)C4—C51.4093 (10)
C14—H14A0.98C5—C61.3888 (10)
C14—H14B0.98C5—H50.95
C14—H14C0.98C6—C11.3928 (10)
C3—C21.3835 (10)C6—H60.95
C3—C41.4090 (9)C1—C21.3984 (10)
C3—H30.95C9—C81.5261 (10)
C13—C151.5223 (12)C9—H9A0.99
C13—C161.5244 (11)C9—H9B0.99
C12—N21.3545 (9)C8—H8A0.99
N2—C91.4592 (9)C8—H8B0.99
N2—C101.4635 (9)C16—H16A0.98
C10—C111.5260 (10)C16—H16B0.98
C10—H10A0.99C16—H16C0.98
C10—H10B0.99C15—H15A0.98
C11—C71.5302 (10)C15—H15B0.98
C11—H11A0.99C15—H15C0.98
C11—H11B0.99
C12—O1—C13121.34 (5)C4—N1—H1117.7
C13—C14—H14A109.5C7—N1—H1117.7
C13—C14—H14B109.5N1—C4—C3118.43 (6)
H14A—C14—H14B109.5N1—C4—C5123.40 (6)
C13—C14—H14C109.5C3—C4—C5118.14 (6)
H14A—C14—H14C109.5C6—C5—C4120.58 (6)
H14B—C14—H14C109.5C6—C5—H5119.7
C2—C3—C4120.59 (6)C4—C5—H5119.7
C2—C3—H3119.7C5—C6—C1120.90 (7)
C4—C3—H3119.7C5—C6—H6119.6
O1—C13—C15110.38 (6)C1—C6—H6119.6
O1—C13—C16102.11 (6)C6—C1—C2118.73 (6)
C15—C13—C16110.06 (7)C6—C1—Cl1120.08 (5)
O1—C13—C14110.10 (6)C2—C1—Cl1121.19 (5)
C15—C13—C14112.80 (7)C3—C2—C1121.01 (6)
C16—C13—C14110.89 (7)C3—C2—Cl2118.14 (5)
O2—C12—O1124.91 (6)C1—C2—Cl2120.85 (5)
O2—C12—N2123.67 (6)N2—C9—C8110.10 (6)
O1—C12—N2111.42 (6)N2—C9—H9A109.6
C12—N2—C9119.98 (6)C8—C9—H9A109.6
C12—N2—C10124.71 (6)N2—C9—H9B109.6
C9—N2—C10114.45 (6)C8—C9—H9B109.6
N2—C10—C11110.14 (6)H9A—C9—H9B108.2
N2—C10—H10A109.6C9—C8—C7110.34 (6)
C11—C10—H10A109.6C9—C8—H8A109.6
N2—C10—H10B109.6C7—C8—H8A109.6
C11—C10—H10B109.6C9—C8—H8B109.6
H10A—C10—H10B108.1C7—C8—H8B109.6
C10—C11—C7112.04 (6)H8A—C8—H8B108.1
C10—C11—H11A109.2C13—C16—H16A109.5
C7—C11—H11A109.2C13—C16—H16B109.5
C10—C11—H11B109.2H16A—C16—H16B109.5
C7—C11—H11B109.2C13—C16—H16C109.5
H11A—C11—H11B107.9H16A—C16—H16C109.5
N1—C7—C11108.61 (6)H16B—C16—H16C109.5
N1—C7—C8112.88 (6)C13—C15—H15A109.5
C11—C7—C8109.72 (6)C13—C15—H15B109.5
N1—C7—H7108.5H15A—C15—H15B109.5
C11—C7—H7108.5C13—C15—H15C109.5
C8—C7—H7108.5H15A—C15—H15C109.5
C4—N1—C7124.62 (6)H15B—C15—H15C109.5
C12—O1—C13—C1565.40 (8)C2—C3—C4—N1176.69 (7)
C12—O1—C13—C16177.61 (6)C2—C3—C4—C51.34 (10)
C12—O1—C13—C1459.79 (9)N1—C4—C5—C6175.62 (7)
C13—O1—C12—O24.42 (11)C3—C4—C5—C62.31 (11)
C13—O1—C12—N2175.50 (6)C4—C5—C6—C11.23 (12)
O2—C12—N2—C95.18 (11)C5—C6—C1—C20.86 (11)
O1—C12—N2—C9174.90 (6)C5—C6—C1—Cl1179.73 (6)
O2—C12—N2—C10174.00 (7)C4—C3—C2—C10.72 (11)
O1—C12—N2—C106.08 (10)C4—C3—C2—Cl2178.95 (5)
C12—N2—C10—C11134.30 (7)C6—C1—C2—C31.83 (11)
C9—N2—C10—C1156.33 (8)Cl1—C1—C2—C3179.31 (6)
N2—C10—C11—C753.30 (8)C6—C1—C2—Cl2177.83 (6)
C10—C11—C7—N1177.63 (6)Cl1—C1—C2—Cl21.03 (9)
C10—C11—C7—C853.82 (8)C12—N2—C9—C8131.49 (7)
C11—C7—N1—C4169.17 (7)C10—N2—C9—C858.59 (8)
C8—C7—N1—C468.92 (9)N2—C9—C8—C756.87 (7)
C7—N1—C4—C3166.47 (7)N1—C7—C8—C9176.41 (6)
C7—N1—C4—C515.61 (12)C11—C7—C8—C955.13 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.882.122.9740 (8)163
C3—H3···O2i0.952.583.3486 (9)138
Symmetry code: (i) x+1/2, y+3/2, z+1.

Experimental details

Crystal data
Chemical formulaC16H22Cl2N2O2
Mr345.25
Crystal system, space groupOrthorhombic, P212121
Temperature (K)100
a, b, c (Å)9.7825 (6), 10.6075 (6), 16.8215 (10)
V3)1745.53 (18)
Z4
Radiation typeMo Kα
µ (mm1)0.38
Crystal size (mm)0.40 × 0.40 × 0.30
Data collection
DiffractometerBruker Kappa APEXII DUO CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.662, 0.749
No. of measured, independent and
observed [I > 2σ(I)] reflections
34136, 13197, 11079
Rint0.024
(sin θ/λ)max1)0.973
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.079, 1.00
No. of reflections13197
No. of parameters202
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.44, 0.19
Absolute structureFlack (1983), ???? Friedel pairs
Absolute structure parameter0.01 (2)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.882.122.9740 (8)163.4
C3—H3···O2i0.952.583.3486 (9)137.8
Symmetry code: (i) x+1/2, y+3/2, z+1.
 

Acknowledgements

We gratefully acknowledge a grant from the Higher Education Commission of Pakistan under the IRSIP programme to support PhD students. The Bruker Kappa APEXII DUO was purchased with funding from NSF grant CHE-0741837. The work was supported in part by grants from the US Public Health Service and National Institutes of Health (DA06284 and DA13449).

References

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