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ISSN: 2056-9890

2-Hydr­­oxy-(2-methyl-1H-indol-3-ylmethyl­­idene)benzohydrazide ethanol solvate

aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my

(Received 22 April 2008; accepted 24 April 2008; online 3 May 2008)

In the title compound, C17H15N3O2·C2H6O, Schiff base molecules are linked by a hydr­oxy–amido hydrogen bond into a helical chain running along the b axis. This chain is consolidated by two other hydrogen bonds; the ethanol solvent mol­ecule is a hydrogen-bond donor to the amide group and a hydrogen-bond acceptor for the indolyl NH group of an adjacent Schiff base mol­ecule.

Related literature

For reports on the medicinal properties of the unsubstituted compound, indol-3-ylmethyl­idene-2-hydroxy­benzohydrazide, see: Alemany et al. (1967[Alemany, A., Bernabe Pajares, M. F., Fernandez Alvarez, E., Lora-Tamayo, M. & Nieto Lopez, O. (1967). Bull. Soc. Chim. Fr. pp. 780-786.]); Fujikawa et al. (1966[Fujikawa, F., Yamashita, I., Seno, T., Sasaki, M., Naito, M. & Tsukuma, S. (1966). Yakugaku Zasshi, 86, 801-804.]); Nakata et al. (1966[Nakata, H., Harada, H. & Hirata, Y. (1966). Tetrahedron Lett. pp. 2515-2522.]); Singh et al. (1984[Singh, I. P., Gurtu, S., Kumar, A., Sinha, J. N., Bhargava, K. P. & Shanker, K. (1984). Archiv Pharm. (Weinheim), 317, 609-614.]).

[Scheme 1]

Experimental

Crystal data
  • C17H15N3O2·C2H6O

  • Mr = 339.39

  • Monoclinic, P 21 /c

  • a = 7.5907 (1) Å

  • b = 11.2269 (2) Å

  • c = 20.3014 (3) Å

  • β = 91.924 (1)°

  • V = 1729.11 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 100 (2) K

  • 0.34 × 0.27 × 0.12 mm

Data collection
  • Bruker SMART APEX diffractometer

  • Absorption correction: none

  • 20827 measured reflections

  • 3967 independent reflections

  • 2869 reflections with I > 2σ(I)

  • Rint = 0.056

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.162

  • S = 1.13

  • 3967 reflections

  • 230 parameters

  • H-atom parameters constrained

  • Δρmax = 0.31 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1o⋯O2i 0.84 1.76 2.594 (2) 176
O3—H3o⋯O2 0.84 2.02 2.843 (2) 165
N1—H1n⋯O1 0.88 1.91 2.618 (2) 136
N3—H3n⋯O3ii 0.88 1.96 2.824 (2) 168
Symmetry codes: (i) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) -x, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. 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: X-SEED (Barbour, 2001[Barbour, L. J. (2001). J. Supramol. Chem. 1, 189-191.]); software used to prepare material for publication: publCIF (Westrip, 2008[Westrip, S. P. (2008). publCIF. In preparation.]).

Supporting information


Comment top

There are no reports of the title Schiff base but there are several reports on the medicinal properties of the unsubstituted compound, indol-3-ylmethylidene-2-hydroxybenzohydrazide (Alemany et al., 1967; Fujikawa et al., 1966; Nakata et al., 1966; Singh et al., 1984). The methyl-substituted title compound (Scheme I, Fig. 1) is a planar molecule that is linked by a hydroxy···amido hydrogen bond into a helical chain that runs along the b-axis of the monoclinic unit cell (Fig. 2). The chain is consolidated by two other hydrogen bonds: the ethanol molecule is hydrogen-bond donor to the amido unit well as hydrogen-bond acceptor to the aminoindolyl unit of adjacent Schiff bases.

Related literature top

For reports on the medicinal properties of the unsubstituted compound, indol-3-ylmethylidene-2-hydroxybenzohydrazide, see: Alemany et al. (1967); Fujikawa et al. (1966); Nakata et al. (1966); Singh et al. (1984).

Experimental top

2-Hydroxybenzohyrazide (0.60 g, 4 mmol) and 2-methyl-1H-indole-3-carboxaldehyde (0.63 g, 4 mmol) were heated in ethanol (30 ml) for 3 h. The solvent was removed by evaporation and the light brown product recrystallized from ethanol.

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H 0.95 to 0.99 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2–1.5 U(C).

The oxygen- and nitrogen-bound H-atoms were also generated geometrically (O–H 0.84, N–H 0.88 Å).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures top
[Figure 1] Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of C17H15N3O2.C2H6O at the 70% probability level. Hydrogen atoms are drawn as spheres of arbitrary radiius.
[Figure 2] Fig. 2. Hydrogen-bonded chain motif.
2-Hydroxy-(2-methyl-1H-indol-3-ylmethylidene)benzohydrazide ethanol solvate top
Crystal data top
C17H15N3O2·C2H6OF(000) = 720
Mr = 339.39Dx = 1.304 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 6771 reflections
a = 7.5907 (1) Åθ = 2.7–28.2°
b = 11.2269 (2) ŵ = 0.09 mm1
c = 20.3014 (3) ÅT = 100 K
β = 91.924 (1)°Prism, yellow
V = 1729.11 (5) Å30.34 × 0.27 × 0.12 mm
Z = 4
Data collection top
Bruker SMART APEX
diffractometer
2869 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.056
Graphite monochromatorθmax = 27.5°, θmin = 2.0°
ω scansh = 99
20827 measured reflectionsk = 1414
3967 independent reflectionsl = 2622
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)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.162H-atom parameters constrained
S = 1.13 w = 1/[σ2(Fo2) + (0.0721P)2 + 0.9553P]
where P = (Fo2 + 2Fc2)/3
3967 reflections(Δ/σ)max = 0.001
230 parametersΔρmax = 0.31 e Å3
0 restraintsΔρmin = 0.30 e Å3
Crystal data top
C17H15N3O2·C2H6OV = 1729.11 (5) Å3
Mr = 339.39Z = 4
Monoclinic, P21/cMo Kα radiation
a = 7.5907 (1) ŵ = 0.09 mm1
b = 11.2269 (2) ÅT = 100 K
c = 20.3014 (3) Å0.34 × 0.27 × 0.12 mm
β = 91.924 (1)°
Data collection top
Bruker SMART APEX
diffractometer
2869 reflections with I > 2σ(I)
20827 measured reflectionsRint = 0.056
3967 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.162H-atom parameters constrained
S = 1.13Δρmax = 0.31 e Å3
3967 reflectionsΔρmin = 0.30 e Å3
230 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.60372 (18)0.39960 (12)0.26124 (6)0.0287 (3)
H1O0.64880.33420.25070.043*
O20.26721 (17)0.69310 (12)0.26809 (7)0.0272 (3)
O30.0963 (2)0.65666 (15)0.29094 (8)0.0409 (4)
H3O0.01260.66980.29160.061*
N10.3897 (2)0.53879 (15)0.32419 (7)0.0255 (4)
H1N0.45630.47460.32360.031*
N20.3081 (2)0.57121 (15)0.38183 (8)0.0263 (4)
N30.1852 (2)0.47451 (15)0.59623 (8)0.0265 (4)
H3N0.17300.43720.63390.032*
C10.5678 (2)0.46480 (17)0.20605 (9)0.0243 (4)
C20.6339 (3)0.43017 (18)0.14536 (10)0.0283 (4)
H20.70250.35970.14250.034*
C30.5997 (3)0.4978 (2)0.08976 (10)0.0313 (5)
H30.64620.47420.04890.038*
C40.4981 (3)0.60009 (19)0.09301 (10)0.0311 (4)
H40.47600.64710.05470.037*
C50.4291 (2)0.63320 (18)0.15254 (9)0.0270 (4)
H50.35830.70280.15450.032*
C60.4616 (2)0.56639 (17)0.20990 (9)0.0233 (4)
C70.3674 (2)0.60467 (17)0.26980 (9)0.0233 (4)
C80.3263 (2)0.49282 (18)0.42813 (9)0.0258 (4)
H80.38590.42040.41940.031*
C90.2589 (2)0.51224 (18)0.49235 (9)0.0258 (4)
C100.2617 (2)0.42767 (18)0.54211 (9)0.0266 (4)
C110.3331 (3)0.30424 (19)0.54307 (10)0.0324 (5)
H11A0.26720.25560.57390.049*
H11B0.45780.30600.55720.049*
H11C0.32120.26980.49880.049*
C120.1752 (2)0.61732 (18)0.51780 (9)0.0262 (4)
C130.1327 (3)0.73007 (19)0.49295 (10)0.0304 (4)
H130.16210.75170.44940.036*
C140.0472 (3)0.8094 (2)0.53269 (11)0.0343 (5)
H140.01850.88640.51610.041*
C150.0014 (3)0.7792 (2)0.59706 (11)0.0359 (5)
H150.05860.83560.62310.043*
C160.0425 (3)0.66914 (19)0.62286 (10)0.0314 (5)
H160.01230.64830.66640.038*
C170.1302 (2)0.58892 (18)0.58288 (9)0.0262 (4)
C180.1888 (3)0.7654 (2)0.28171 (11)0.0384 (5)
H18A0.30590.75840.30140.046*
H18B0.20770.77990.23390.046*
C190.0926 (3)0.8698 (2)0.31203 (13)0.0453 (6)
H19A0.16760.94070.30880.068*
H19B0.01630.88390.28860.068*
H19C0.06370.85290.35850.068*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0333 (8)0.0315 (7)0.0215 (7)0.0069 (6)0.0051 (5)0.0015 (6)
O20.0237 (7)0.0306 (7)0.0276 (7)0.0012 (5)0.0066 (5)0.0015 (6)
O30.0288 (8)0.0494 (10)0.0452 (10)0.0007 (7)0.0132 (7)0.0105 (7)
N10.0239 (8)0.0333 (9)0.0198 (8)0.0029 (7)0.0060 (6)0.0004 (7)
N20.0214 (8)0.0376 (9)0.0202 (8)0.0009 (7)0.0053 (6)0.0021 (7)
N30.0232 (8)0.0368 (9)0.0197 (8)0.0011 (7)0.0043 (6)0.0004 (7)
C10.0210 (9)0.0310 (10)0.0209 (9)0.0029 (7)0.0021 (7)0.0010 (7)
C20.0244 (9)0.0346 (10)0.0260 (10)0.0019 (8)0.0041 (7)0.0026 (8)
C30.0292 (10)0.0440 (12)0.0211 (10)0.0011 (9)0.0062 (8)0.0014 (8)
C40.0327 (10)0.0399 (11)0.0208 (9)0.0021 (9)0.0019 (8)0.0045 (8)
C50.0251 (9)0.0308 (10)0.0252 (10)0.0008 (8)0.0021 (7)0.0016 (8)
C60.0194 (8)0.0302 (10)0.0205 (9)0.0040 (7)0.0028 (7)0.0016 (7)
C70.0185 (8)0.0279 (9)0.0236 (9)0.0039 (7)0.0016 (7)0.0004 (7)
C80.0192 (9)0.0341 (10)0.0242 (10)0.0012 (7)0.0029 (7)0.0017 (8)
C90.0173 (8)0.0379 (11)0.0224 (9)0.0022 (7)0.0018 (7)0.0010 (8)
C100.0184 (8)0.0391 (11)0.0224 (9)0.0029 (8)0.0034 (7)0.0018 (8)
C110.0308 (10)0.0400 (11)0.0268 (10)0.0006 (9)0.0069 (8)0.0005 (9)
C120.0167 (8)0.0396 (11)0.0225 (9)0.0030 (8)0.0022 (7)0.0026 (8)
C130.0222 (9)0.0410 (11)0.0279 (10)0.0020 (8)0.0021 (7)0.0017 (9)
C140.0264 (10)0.0362 (11)0.0402 (12)0.0025 (9)0.0012 (9)0.0009 (9)
C150.0280 (10)0.0450 (12)0.0349 (11)0.0038 (9)0.0026 (8)0.0087 (10)
C160.0238 (9)0.0447 (12)0.0258 (10)0.0009 (8)0.0042 (8)0.0055 (9)
C170.0177 (8)0.0382 (11)0.0226 (9)0.0032 (7)0.0012 (7)0.0020 (8)
C180.0253 (10)0.0568 (14)0.0332 (11)0.0033 (10)0.0047 (8)0.0130 (10)
C190.0292 (11)0.0548 (15)0.0520 (15)0.0108 (10)0.0026 (10)0.0041 (12)
Geometric parameters (Å, º) top
O1—C11.358 (2)C8—H80.9500
O1—H1O0.8400C9—C101.386 (3)
O2—C71.250 (2)C9—C121.444 (3)
O3—C181.417 (3)C10—C111.488 (3)
O3—H3O0.8400C11—H11A0.9800
N1—C71.335 (2)C11—H11B0.9800
N1—N21.391 (2)C11—H11C0.9800
N1—H1N0.8800C12—C131.396 (3)
N2—C81.292 (3)C12—C171.412 (3)
N3—C101.365 (2)C13—C141.379 (3)
N3—C171.375 (3)C13—H130.9500
N3—H3N0.8800C14—C151.405 (3)
C1—C61.401 (3)C14—H140.9500
C1—C21.401 (3)C15—C161.374 (3)
C2—C31.378 (3)C15—H150.9500
C2—H20.9500C16—C171.396 (3)
C3—C41.386 (3)C16—H160.9500
C3—H30.9500C18—C191.502 (4)
C4—C51.384 (3)C18—H18A0.9900
C4—H40.9500C18—H18B0.9900
C5—C61.400 (3)C19—H19A0.9800
C5—H50.9500C19—H19B0.9800
C6—C71.494 (3)C19—H19C0.9800
C8—C91.433 (3)
C1—O1—H1O109.5C9—C10—C11130.10 (18)
C18—O3—H3O109.5C10—C11—H11A109.5
C7—N1—N2120.20 (16)C10—C11—H11B109.5
C7—N1—H1N119.9H11A—C11—H11B109.5
N2—N1—H1N119.9C10—C11—H11C109.5
C8—N2—N1113.21 (16)H11A—C11—H11C109.5
C10—N3—C17109.62 (16)H11B—C11—H11C109.5
C10—N3—H3N125.2C13—C12—C17118.84 (18)
C17—N3—H3N125.2C13—C12—C9135.28 (18)
O1—C1—C6119.52 (16)C17—C12—C9105.88 (17)
O1—C1—C2120.54 (17)C14—C13—C12118.82 (19)
C6—C1—C2119.93 (17)C14—C13—H13120.6
C3—C2—C1120.29 (19)C12—C13—H13120.6
C3—C2—H2119.9C13—C14—C15121.6 (2)
C1—C2—H2119.9C13—C14—H14119.2
C2—C3—C4120.49 (19)C15—C14—H14119.2
C2—C3—H3119.8C16—C15—C14120.8 (2)
C4—C3—H3119.8C16—C15—H15119.6
C5—C4—C3119.45 (19)C14—C15—H15119.6
C5—C4—H4120.3C15—C16—C17117.72 (19)
C3—C4—H4120.3C15—C16—H16121.1
C4—C5—C6121.42 (19)C17—C16—H16121.1
C4—C5—H5119.3N3—C17—C16129.46 (18)
C6—C5—H5119.3N3—C17—C12108.30 (17)
C5—C6—C1118.38 (17)C16—C17—C12122.23 (19)
C5—C6—C7116.57 (17)O3—C18—C19112.73 (18)
C1—C6—C7124.88 (17)O3—C18—H18A109.0
O2—C7—N1121.54 (17)C19—C18—H18A109.0
O2—C7—C6120.86 (17)O3—C18—H18B109.0
N1—C7—C6117.57 (16)C19—C18—H18B109.0
N2—C8—C9121.71 (18)H18A—C18—H18B107.8
N2—C8—H8119.1C18—C19—H19A109.5
C9—C8—H8119.1C18—C19—H19B109.5
C10—C9—C8124.18 (18)H19A—C19—H19B109.5
C10—C9—C12107.16 (17)C18—C19—H19C109.5
C8—C9—C12128.66 (18)H19A—C19—H19C109.5
N3—C10—C9109.04 (18)H19B—C19—H19C109.5
N3—C10—C11120.86 (17)
C7—N1—N2—C8173.12 (16)C17—N3—C10—C11179.95 (17)
O1—C1—C2—C3178.81 (17)C8—C9—C10—N3179.13 (17)
C6—C1—C2—C32.2 (3)C12—C9—C10—N30.1 (2)
C1—C2—C3—C40.7 (3)C8—C9—C10—C111.4 (3)
C2—C3—C4—C50.8 (3)C12—C9—C10—C11179.53 (19)
C3—C4—C5—C60.8 (3)C10—C9—C12—C13179.7 (2)
C4—C5—C6—C10.6 (3)C8—C9—C12—C130.7 (4)
C4—C5—C6—C7174.79 (17)C10—C9—C12—C170.4 (2)
O1—C1—C6—C5178.89 (16)C8—C9—C12—C17178.61 (18)
C2—C1—C6—C52.1 (3)C17—C12—C13—C140.4 (3)
O1—C1—C6—C76.1 (3)C9—C12—C13—C14178.8 (2)
C2—C1—C6—C7172.88 (17)C12—C13—C14—C150.3 (3)
N2—N1—C7—O23.4 (3)C13—C14—C15—C160.7 (3)
N2—N1—C7—C6178.81 (15)C14—C15—C16—C170.2 (3)
C5—C6—C7—O21.0 (3)C10—N3—C17—C16178.45 (19)
C1—C6—C7—O2176.05 (17)C10—N3—C17—C120.8 (2)
C5—C6—C7—N1176.83 (16)C15—C16—C17—N3179.69 (19)
C1—C6—C7—N11.8 (3)C15—C16—C17—C120.5 (3)
N1—N2—C8—C9176.97 (16)C13—C12—C17—N3179.82 (16)
N2—C8—C9—C10174.44 (18)C9—C12—C17—N30.7 (2)
N2—C8—C9—C124.4 (3)C13—C12—C17—C160.9 (3)
C17—N3—C10—C90.5 (2)C9—C12—C17—C16178.58 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1o···O2i0.841.762.594 (2)176
O3—H3o···O20.842.022.843 (2)165
N1—H1n···O10.881.912.618 (2)136
N3—H3n···O3ii0.881.962.824 (2)168
Symmetry codes: (i) x+1, y1/2, z+1/2; (ii) x, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC17H15N3O2·C2H6O
Mr339.39
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)7.5907 (1), 11.2269 (2), 20.3014 (3)
β (°) 91.924 (1)
V3)1729.11 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.34 × 0.27 × 0.12
Data collection
DiffractometerBruker SMART APEX
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
20827, 3967, 2869
Rint0.056
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.162, 1.13
No. of reflections3967
No. of parameters230
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.31, 0.30

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1o···O2i0.841.762.594 (2)176
O3—H3o···O20.842.022.843 (2)165
N1—H1n···O10.881.912.618 (2)136
N3—H3n···O3ii0.881.962.824 (2)168
Symmetry codes: (i) x+1, y1/2, z+1/2; (ii) x, y+1, z+1.
 

Acknowledgements

We acknowledge the SAGA grant (06–02-03–0147) for support of this study, and the University of Malaya for the purchase of the diffractometer.

References

First citationAlemany, A., Bernabe Pajares, M. F., Fernandez Alvarez, E., Lora-Tamayo, M. & Nieto Lopez, O. (1967). Bull. Soc. Chim. Fr. pp. 780–786.  Google Scholar
First citationBarbour, L. J. (2001). J. Supramol. Chem. 1, 189–191.  CrossRef CAS Google Scholar
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