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ISSN: 2056-9890

N-[(1,3-Benzodioxol-5-yl)meth­yl]-4-methyl­benzamide: an analogue of capsaicin

aDepartmento de Química, Universidade Federal de São Carlos, 13565-905 São Carlos, SP, Brazil, and bDepartmento de Farmacia, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
*Correspondence e-mail: stellamaganhi@gmail.com

(Received 21 January 2013; accepted 22 January 2013; online 2 February 2013)

In the title compound, C16H15NO3, the five-membered 1,3-dioxole ring is in an envelope conformation with the methyl­ene C atom as the flap atom [lying 0.202 (3) Å out of the plane formed by the other four atoms]. The benzene ring makes a dihedral angle of 84.65 (4)° with the best least-squares plane through the 1,3-benzodioxole fused-ring system, which substitutes the 2-methoxyphenol moiety in capsaicin. In the crystal, mol­ecules are connected into a zigzag supra­molecular chain along the c-axis direction by N—H⋯O hydrogen bonds. These chains are connected into a layer in the ac plane by C—H⋯π inter­actions.

Related literature

For the biological activity of capsaicin, see: Okamoto et al. (2011[Okamoto, M., Irii, H., Tahara, Y., Ishii, H., Hirao, A., Udagawa, H., Hiramoto, M., Yasuda, K., Takanishi, A., Shibata, S. & Shimizu, I. (2011). J. Med. Chem. 54, 6295-6304.]). For ring conformational analysis, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C16H15NO3

  • Mr = 269.29

  • Monoclinic, P 21 /c

  • a = 4.9810 (2) Å

  • b = 26.652 (1) Å

  • c = 10.0545 (3) Å

  • β = 92.139 (2)°

  • V = 1333.84 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 290 K

  • 0.33 × 0.24 × 0.16 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: numerical (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.940, Tmax = 0.951

  • 4550 measured reflections

  • 2602 independent reflections

  • 1698 reflections with I > 2σ(I)

  • Rint = 0.023

Refinement
  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.149

  • S = 1.03

  • 2602 reflections

  • 182 parameters

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C1–C6 and C10–C15 rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N1⋯O3i 0.91 2.08 2.958 (2) 162
C7—H7ACg1 0.97 2.74 3.603 (3) 149
C16—H16CCg2 0.96 2.96 3.829 (2) 151
Symmetry code: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: COLLECT (Nonius, 1999[Nonius (1999). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and SCALEPACK; program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: Marvinsketch (Chemaxon, 2010[Chemaxon (2010). Marvinsketch. http://www.chemaxon.com.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Capsaicin is the main pungent compound found in chilli peppers of the genus Capsicum and is found to exert multiple pharmacological and physiological effects, including analgesic, anti-cancer, anti-inflammatory, anti-oxidant and anti-obesity (Okamoto et al. 2011). This makes capsaicin an excellent scaffold for the rational design of analogues with better biological activity. The title compound (I) is a capsaicin-like derivative where the 2-methoxyphenol ring was substituted with a benzodioxol ring and the amide aliphatic chain was replaced with a 4-methylbenzoyl group. As suitable crystals were obtained from its hexane solution, a crystal structure determination of (I) was undertaken.

In (I), Fig. 1, the 1,3-dioxole five membered ring is in an envelope configuration with the C7 atom lying 0.202 (3) Å out of the plane formed by the other four atoms. The ring puckering parameters are q2 = 0.128 (2) Å and ϕ2 = 149.9 (9)° (Cremer & Pople, 1975).

The crystal packing of (I), Table 1, is sustained by N—H···O and C—H···π interactions, leading to supramolecular layers in the ac plane.

Related literature top

For the biological activity of capsaicin, see: Okamoto et al. (2011). For ring conformational analysis, see: Cremer & Pople (1975).

Experimental top

1-(1,3-Benzodioxol-5-yl)methanamine (0.755 g, 5 mmol) was dissolved in chloroform (20 ml) and then triethylamine (411 µL, 5.5 mmol) and DMF (40 µL, 0,5 mmol) were added. The mixture was stirred for 30 min under argon atmosphere. 4-Methylbenzoyl chloride (661 µL, 5 mmol) was added in portions and stirred over 24 h. The organic layer was washed with 5% HCl aqueous solution, water, brine and dried over anhydrous Na2SO4. The solvent was removed under high vacuum and the title compound was obtained after recrystallization from hot hexane. Analytical data: white solid, yield 71.4° (0.96 g, 3.57 mmol). 1H-NMR NMR (300 MHz, DMSO-d6, ppm): δ 8.87 (1H, bt, J = 5.8 Hz, 9-NH), 7.79 (2H, d, J = 8.2 Hz,12, 13-ArH), 7.27 (2H, d, J = 8.2 Hz, 14, 15-ArH), 6.83 (3H, m, 4, 5, 7-ArH), 5.98 (2H, s, 1-OCH2O), 4.38 (2H, d, J = 6.0 Hz, 8-CH2), 2.36 (3H, s, 15-CH3). 13C NMR (75 MHz, DMSO-d6, ppm) δ: 165.9 (C9), 147.18 (C2), 145.98 (C1), 141.02 (C13), 133.68 (C10), 131.67 (C5), 128.77 (C12, C14), 127.21 (C11, C15), 120.42 (C4), 107.94 (C3), 107.92 (C6), 100.74 (C7), 42.36 (C8), 20.89 (C16); Anal. calcd. for: C16H15NO3 (269.11): C 71.36, H 5.61, N 5.20, found: C 71.30, H 5.74, N 5.17, mp: 404.7–405.2 K.

Refinement top

The H atoms were geometrically placed (C—H = 0.93–0.97 Å) and refined as riding with Uiso(H) = 1.2–1.5Ueq(C). The N—H H atom was located in a difference map, fixed in this position with Uiso(H) = 1.2Ueq(N).

Computing details top

Data collection: COLLECT (Nonius, 1999); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997) and SCALEPACK; program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012)\bbr00; software used to prepare material for publication: Marvinsketch (Chemaxon, 2010) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing atom labelling scheme and displacement ellipsoids at the 50% probability level (arbitrary spheres for the H atoms).
N-[(1,3-Benzodioxol-5-yl)methyl]-4-methylbenzamide top
Crystal data top
C16H15NO3F(000) = 568
Mr = 269.29Dx = 1.341 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5124 reflections
a = 4.9810 (2) Åθ = 3.1–27.5°
b = 26.652 (1) ŵ = 0.09 mm1
c = 10.0545 (3) ÅT = 290 K
β = 92.139 (2)°Prism, colourless
V = 1333.84 (8) Å30.33 × 0.24 × 0.16 mm
Z = 4
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2602 independent reflections
Radiation source: fine-focus sealed tube1698 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
Detector resolution: 0 pixels mm-1θmax = 26.0°, θmin = 3.1°
ϕ and ω scansh = 66
Absorption correction: numerical
(SADABS; Sheldrick, 1996)
k = 3230
Tmin = 0.940, Tmax = 0.951l = 1212
4550 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)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.149H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0859P)2 + 0.0674P]
where P = (Fo2 + 2Fc2)/3
2602 reflections(Δ/σ)max < 0.001
182 parametersΔρmax = 0.21 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C16H15NO3V = 1333.84 (8) Å3
Mr = 269.29Z = 4
Monoclinic, P21/cMo Kα radiation
a = 4.9810 (2) ŵ = 0.09 mm1
b = 26.652 (1) ÅT = 290 K
c = 10.0545 (3) Å0.33 × 0.24 × 0.16 mm
β = 92.139 (2)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2602 independent reflections
Absorption correction: numerical
(SADABS; Sheldrick, 1996)
1698 reflections with I > 2σ(I)
Tmin = 0.940, Tmax = 0.951Rint = 0.023
4550 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0500 restraints
wR(F2) = 0.149H-atom parameters constrained
S = 1.03Δρmax = 0.21 e Å3
2602 reflectionsΔρmin = 0.20 e Å3
182 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
O10.0219 (3)0.06137 (6)0.88685 (15)0.0754 (5)
O20.0295 (3)0.00662 (6)0.71012 (17)0.0797 (5)
O30.4080 (3)0.24272 (5)0.87268 (12)0.0634 (4)
N10.4208 (3)0.22490 (6)0.65426 (14)0.0496 (4)
H1N10.37680.23570.57020.060*
C10.1365 (4)0.08000 (7)0.78849 (19)0.0525 (5)
C20.1354 (4)0.04694 (8)0.6838 (2)0.0585 (5)
C30.2867 (5)0.05485 (8)0.5769 (2)0.0733 (6)
H30.28780.03220.50650.088*
C40.4407 (4)0.09851 (8)0.5771 (2)0.0649 (6)
H40.54830.10470.50530.078*
C50.4398 (3)0.13305 (7)0.68029 (18)0.0503 (5)
C60.2825 (3)0.12319 (7)0.79020 (18)0.0505 (5)
H60.27820.14530.86160.061*
C70.1575 (5)0.01955 (9)0.8290 (2)0.0740 (7)
H7A0.34440.02790.80940.089*
H7B0.15100.00860.89030.089*
C80.5961 (4)0.18139 (7)0.6730 (2)0.0556 (5)
H8A0.70420.18560.75450.067*
H8B0.71690.17950.59970.067*
C90.3359 (3)0.25214 (7)0.75640 (17)0.0467 (5)
C100.1449 (3)0.29384 (7)0.72454 (16)0.0440 (4)
C110.0105 (4)0.29652 (7)0.60682 (19)0.0547 (5)
H110.00650.27190.54220.066*
C120.1888 (4)0.33522 (8)0.5853 (2)0.0620 (6)
H120.29180.33600.50620.074*
C130.2198 (4)0.37300 (7)0.6775 (2)0.0535 (5)
C140.0639 (4)0.37058 (8)0.7936 (2)0.0598 (5)
H140.07790.39580.85700.072*
C150.1126 (4)0.33142 (8)0.81753 (18)0.0576 (5)
H150.21170.33030.89770.069*
C160.4161 (4)0.41514 (8)0.6534 (2)0.0710 (6)
H16A0.36340.43450.57820.106*
H16B0.41800.43630.73070.106*
H16C0.59240.40160.63580.106*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0884 (10)0.0677 (10)0.0708 (10)0.0258 (8)0.0130 (8)0.0058 (8)
O20.0972 (11)0.0531 (9)0.0875 (12)0.0117 (8)0.0135 (9)0.0127 (8)
O30.0857 (10)0.0681 (10)0.0363 (8)0.0119 (8)0.0003 (6)0.0050 (7)
N10.0628 (9)0.0497 (9)0.0366 (8)0.0042 (7)0.0049 (7)0.0051 (7)
C10.0582 (11)0.0506 (12)0.0482 (11)0.0027 (9)0.0053 (9)0.0010 (9)
C20.0697 (13)0.0469 (11)0.0577 (13)0.0060 (10)0.0126 (10)0.0048 (10)
C30.1024 (17)0.0590 (14)0.0577 (14)0.0133 (13)0.0077 (12)0.0177 (11)
C40.0821 (14)0.0646 (14)0.0486 (12)0.0180 (11)0.0101 (10)0.0022 (10)
C50.0545 (11)0.0504 (11)0.0459 (11)0.0121 (9)0.0000 (8)0.0027 (9)
C60.0592 (11)0.0481 (11)0.0440 (11)0.0028 (9)0.0003 (8)0.0066 (9)
C70.0766 (14)0.0614 (14)0.0827 (17)0.0153 (12)0.0136 (13)0.0005 (12)
C80.0553 (11)0.0590 (12)0.0530 (11)0.0067 (10)0.0089 (8)0.0053 (9)
C90.0559 (10)0.0482 (11)0.0361 (10)0.0035 (8)0.0040 (8)0.0042 (8)
C100.0507 (10)0.0452 (10)0.0365 (9)0.0044 (8)0.0069 (7)0.0020 (8)
C110.0632 (11)0.0533 (12)0.0474 (11)0.0016 (9)0.0009 (9)0.0075 (9)
C120.0610 (12)0.0660 (14)0.0582 (13)0.0061 (11)0.0090 (9)0.0025 (11)
C130.0481 (10)0.0524 (12)0.0605 (12)0.0026 (9)0.0088 (9)0.0040 (10)
C140.0707 (13)0.0547 (13)0.0544 (12)0.0039 (10)0.0093 (10)0.0095 (10)
C150.0712 (13)0.0598 (13)0.0417 (11)0.0020 (10)0.0008 (9)0.0037 (9)
C160.0593 (13)0.0664 (14)0.0879 (17)0.0101 (11)0.0121 (11)0.0065 (12)
Geometric parameters (Å, º) top
O1—C11.380 (2)C7—H7B0.9700
O1—C71.417 (3)C8—H8A0.9700
O2—C21.384 (2)C8—H8B0.9700
O2—C71.418 (3)C9—C101.490 (3)
O3—C91.2358 (19)C10—C151.384 (3)
N1—C91.339 (2)C10—C111.392 (3)
N1—C81.459 (2)C11—C121.373 (3)
N1—H1N10.9124C11—H110.9300
C1—C61.361 (3)C12—C131.382 (3)
C1—C21.372 (3)C12—H120.9300
C2—C31.352 (3)C13—C141.380 (3)
C3—C41.394 (3)C13—C161.503 (3)
C3—H30.9300C14—C151.380 (3)
C4—C51.387 (3)C14—H140.9300
C4—H40.9300C15—H150.9300
C5—C61.403 (3)C16—H16A0.9600
C5—C81.508 (3)C16—H16B0.9600
C6—H60.9300C16—H16C0.9600
C7—H7A0.9700
C1—O1—C7105.39 (16)C5—C8—H8A109.2
C2—O2—C7105.13 (16)N1—C8—H8B109.2
C9—N1—C8122.43 (15)C5—C8—H8B109.2
C9—N1—H1N1117.9H8A—C8—H8B107.9
C8—N1—H1N1119.5O3—C9—N1121.77 (17)
C6—C1—C2122.7 (2)O3—C9—C10121.03 (16)
C6—C1—O1127.92 (18)N1—C9—C10117.19 (15)
C2—C1—O1109.40 (18)C15—C10—C11117.55 (17)
C3—C2—C1121.5 (2)C15—C10—C9118.96 (16)
C3—C2—O2128.7 (2)C11—C10—C9123.47 (17)
C1—C2—O2109.73 (19)C12—C11—C10120.57 (18)
C2—C3—C4116.89 (19)C12—C11—H11119.7
C2—C3—H3121.6C10—C11—H11119.7
C4—C3—H3121.6C11—C12—C13121.98 (18)
C5—C4—C3122.5 (2)C11—C12—H12119.0
C5—C4—H4118.7C13—C12—H12119.0
C3—C4—H4118.7C14—C13—C12117.42 (18)
C4—C5—C6118.83 (19)C14—C13—C16120.94 (19)
C4—C5—C8120.96 (17)C12—C13—C16121.64 (18)
C6—C5—C8120.17 (17)C13—C14—C15121.17 (18)
C1—C6—C5117.52 (17)C13—C14—H14119.4
C1—C6—H6121.2C15—C14—H14119.4
C5—C6—H6121.2C14—C15—C10121.30 (17)
O1—C7—O2108.35 (18)C14—C15—H15119.4
O1—C7—H7A110.0C10—C15—H15119.4
O2—C7—H7A110.0C13—C16—H16A109.5
O1—C7—H7B110.0C13—C16—H16B109.5
O2—C7—H7B110.0H16A—C16—H16B109.5
H7A—C7—H7B108.4C13—C16—H16C109.5
N1—C8—C5112.19 (14)H16A—C16—H16C109.5
N1—C8—H8A109.2H16B—C16—H16C109.5
C7—O1—C1—C6172.16 (19)C9—N1—C8—C593.3 (2)
C7—O1—C1—C29.7 (2)C4—C5—C8—N1108.75 (19)
C6—C1—C2—C31.8 (3)C6—C5—C8—N168.9 (2)
O1—C1—C2—C3176.41 (17)C8—N1—C9—O32.1 (3)
C6—C1—C2—O2179.79 (16)C8—N1—C9—C10176.54 (15)
O1—C1—C2—O21.6 (2)O3—C9—C10—C1520.0 (3)
C7—O2—C2—C3174.9 (2)N1—C9—C10—C15161.38 (17)
C7—O2—C2—C17.3 (2)O3—C9—C10—C11158.13 (18)
C1—C2—C3—C40.9 (3)N1—C9—C10—C1120.5 (3)
O2—C2—C3—C4178.44 (19)C15—C10—C11—C120.1 (3)
C2—C3—C4—C50.7 (3)C9—C10—C11—C12178.03 (17)
C3—C4—C5—C61.5 (3)C10—C11—C12—C130.6 (3)
C3—C4—C5—C8176.20 (18)C11—C12—C13—C140.0 (3)
C2—C1—C6—C51.0 (3)C11—C12—C13—C16179.77 (18)
O1—C1—C6—C5176.87 (17)C12—C13—C14—C151.1 (3)
C4—C5—C6—C10.6 (3)C16—C13—C14—C15178.62 (18)
C8—C5—C6—C1177.12 (16)C13—C14—C15—C101.7 (3)
C1—O1—C7—O214.2 (2)C11—C10—C15—C141.1 (3)
C2—O2—C7—O113.3 (2)C9—C10—C15—C14179.27 (17)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C1–C6 and C10–C15 rings, respectively.
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O3i0.912.082.958 (2)162
C7—H7A···Cg10.972.743.603 (3)149
C16—H16C···Cg20.962.963.829 (2)151
Symmetry code: (i) x, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formulaC16H15NO3
Mr269.29
Crystal system, space groupMonoclinic, P21/c
Temperature (K)290
a, b, c (Å)4.9810 (2), 26.652 (1), 10.0545 (3)
β (°) 92.139 (2)
V3)1333.84 (8)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.33 × 0.24 × 0.16
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionNumerical
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.940, 0.951
No. of measured, independent and
observed [I > 2σ(I)] reflections
4550, 2602, 1698
Rint0.023
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.149, 1.03
No. of reflections2602
No. of parameters182
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.21, 0.20

Computer programs: COLLECT (Nonius, 1999), SCALEPACK (Otwinowski & Minor, 1997), DENZO (Otwinowski & Minor, 1997) and SCALEPACK, SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012)\bbr00, Marvinsketch (Chemaxon, 2010) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C1–C6 and C10–C15 rings, respectively.
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O3i0.912.082.958 (2)162
C7—H7A···Cg10.972.743.603 (3)149
C16—H16C···Cg20.962.963.829 (2)151
Symmetry code: (i) x, y+1/2, z1/2.
 

Acknowledgements

We thank the Brazilian agencies CNPq (140925/2009–0 to SHM), FAPESP and CAPES for financial support. We also thank Professor Carlos A. De Simone for the data collection.

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