2,4-Dihydr­oxy-N′-(3,4,5-trimethoxy­benzyl­idene)benzohydrazide

Xu, L.; Huang, S.-S.; Zhang, B.-J.; Wang, S.-Y.; Zhang, H.-L.

doi:10.1107/S1600536809035764

organic compounds

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ISSN: 2056-9890

Volume 65| Part 10| October 2009| Page o2412

doi:10.1107/S1600536809035764

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2,4-Dihydroxy-N′-(3,4,5-trimethoxybenzylidene)benzohydrazide

Liang Xu,^a Shan-Shan Huang,^b Bao-Jing Zhang,^b Shou-Yu Wang ^b and Hou-Li Zhang ^b ^*

^aCollege of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116000, People's Republic of China, and ^bDalian Medical University, Dalian 116044, People's Republic of China
^*Correspondence e-mail: dlzhanghouli@163.com

(Received 2 September 2009; accepted 4 September 2009; online 9 September 2009)

In the title compound, C₁₇H₁₈N₂O₆, the molecule is slightly twisted, with a dihedral angle of 18.1 (2)° between the two benzene rings. In the crystal structure, molecules are linked into a network by intermolecular N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds. An intramolecular O—H⋯O hydrogen bond is also present.

Related literature

For the biological properties of Schiff base compounds, see: Brückner et al. (2000 ); Harrop et al. (2003 ); Ren et al. (2002 ). For the crystal structures of some Schiff bases and their complexes, see: Diao (2007 ); Diao et al. (2007 , 2008 ); Huang et al. (2007 ); Li et al. (2007 ).

Experimental

Crystal data

C₁₇H₁₈N₂O₆
M_r = 346.33
Orthorhombic, P b c a
a = 14.601 (1) Å
b = 11.030 (2) Å
c = 20.006 (2) Å
V = 3222.0 (7) Å³
Z = 8
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 298 K
0.20 × 0.20 × 0.20 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.978, T_max = 0.978
18590 measured reflections
3520 independent reflections
2166 reflections with I > 2σ(I)
R_int = 0.069

Refinement

R[F² > 2σ(F²)] = 0.048
wR(F²) = 0.148
S = 1.03
3520 reflections
234 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.41 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O5ⁱ	0.893 (10)	2.109 (13)	2.953 (2)	157 (2)
O3—H3⋯N2ⁱⁱ	0.82	2.52	3.214 (3)	143
O3—H3⋯O1ⁱⁱ	0.82	1.95	2.674 (2)	147
O2—H2⋯O1	0.82	1.79	2.518 (2)	147
Symmetry codes: (i) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]$ ; (ii) $[x-{\script{1\over 2}}, y, -z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809035764/wn2345sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809035764/wn2345Isup2.hkl

checkCIF report

Comment top

Schiff base compounds have been found to have potential pharmacological and antitumor properties (Brückner et al., 2000; Harrop et al., 2003; Ren et al., 2002). Recently, the crystal structures of a few Schiff base compounds derived from the reaction of aldehydes with benzohydrazides have been reported (Diao et al., 2008; Diao et al., 2007; Diao, 2007; Li et al., 2007; Huang et al., 2007). As a continuation of these studies, we report here the crystal structure of the title compound.

The title compound, C₁₇H₁₈N₂O₆ (Fig. 1) is slightly twisted, with a dihedral angle between the two benzene rings of 18.1 (2)°. The torsion angles C9—C8—N2—N1 and C2—C7—N1—N2 are 2.9 (2) and 7.8 (2)°, respectively. In the crystal structure, molecules are linked into a network (Fig. 2) by intermolecular N—H···O, O—H···N and O—H···O hydrogen bonds (Table 1). An intramolecular O—H···O hydrogen bond is also present.

Related literature top

For the biological properties of Schiff base compounds, see: Brückner et al. (2000); Harrop et al. (2003); Ren et al. (2002). For the crystal structures of some Schiff bases and their complexes, see: Diao (2007); Diao et al. (2007, 2008); Huang et al. (2007); Li et al. (2007).

Experimental top

3,4,5-Trimethoxybenzaldehyde (0.1 mmol, 19.6 mg) and 2,4-dihydroxybenzohydrazide (0.1 mmol, 16.8 mg) were dissolved in a methanol solution (20 ml). The mixture was stirred at reflux for 1 h and cooled to room temperature. After allowing the solution to stand in air for a few days, colorless block-like crystals were formed.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level. Hydrogen atoms are represented by spheres of arbitrary radius. The dashed line indicates the intramolecular O—H···O hydrogen bond.
	Fig. 2. The crystal structure of the title compound, viewed along the b axis. Dashed lines indicate hydrogen bonds. Hydrogen atoms not involved in hydrogen bonding have been omitted.

2,4-Dihydroxy-N'-(3,4,5-trimethoxybenzylidene)benzohydrazide top

Crystal data top

C₁₇H₁₈N₂O₆	F(000) = 1456
M_r = 346.33	D_x = 1.428 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 2734 reflections
a = 14.601 (1) Å	θ = 2.5–26.0°
b = 11.030 (2) Å	µ = 0.11 mm⁻¹
c = 20.006 (2) Å	T = 298 K
V = 3222.0 (7) Å³	Block, colorless
Z = 8	0.20 × 0.20 × 0.20 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	3520 independent reflections
Radiation source: fine-focus sealed tube	2166 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.069
ω scans	θ_max = 27.0°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −18→18
T_min = 0.978, T_max = 0.978	k = −12→14
18590 measured reflections	l = −20→25

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.148	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0632P)² + 0.9796P] where P = (F_o² + 2F_c²)/3
3520 reflections	(Δ/σ)_max = 0.001
234 parameters	Δρ_max = 0.41 e Å⁻³
1 restraint	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₁₇H₁₈N₂O₆	V = 3222.0 (7) Å³
M_r = 346.33	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 14.601 (1) Å	µ = 0.11 mm⁻¹
b = 11.030 (2) Å	T = 298 K
c = 20.006 (2) Å	0.20 × 0.20 × 0.20 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	3520 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	2166 reflections with I > 2σ(I)
T_min = 0.978, T_max = 0.978	R_int = 0.069
18590 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.048	1 restraint
wR(F²) = 0.148	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.41 e Å⁻³
3520 reflections	Δρ_min = −0.24 e Å⁻³
234 parameters

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

	x	y	z	U_iso*/U_eq
N1	−0.07006 (12)	0.46657 (17)	0.36310 (9)	0.0409 (5)
N2	0.00500 (12)	0.44220 (16)	0.40282 (9)	0.0410 (4)
O1	0.01502 (10)	0.60011 (16)	0.30628 (8)	0.0528 (5)
O2	−0.04899 (12)	0.72863 (18)	0.21335 (9)	0.0650 (5)
H2	−0.0112	0.7057	0.2409	0.097*
O3	−0.33269 (11)	0.63390 (17)	0.12189 (8)	0.0555 (5)
H3	−0.3814	0.6018	0.1322	0.083*
O4	0.12167 (11)	0.13843 (16)	0.63808 (9)	0.0584 (5)
O5	0.28830 (10)	0.21803 (14)	0.60976 (8)	0.0474 (4)
O6	0.31779 (11)	0.37901 (16)	0.51322 (9)	0.0579 (5)
C1	−0.21013 (15)	0.4894 (2)	0.25893 (12)	0.0420 (5)
H1	−0.2169	0.4251	0.2886	0.050*
C2	−0.13151 (14)	0.56173 (19)	0.26278 (11)	0.0384 (5)
C3	−0.12280 (15)	0.6558 (2)	0.21550 (11)	0.0431 (5)
C4	−0.19085 (16)	0.6778 (2)	0.16936 (12)	0.0465 (6)
H4	−0.1843	0.7408	0.1388	0.056*
C5	−0.26856 (15)	0.6071 (2)	0.16830 (11)	0.0418 (5)
C6	−0.27758 (15)	0.5110 (2)	0.21243 (11)	0.0421 (5)
H6	−0.3290	0.4613	0.2106	0.050*
C7	−0.05838 (14)	0.54391 (19)	0.31173 (11)	0.0396 (5)
C8	−0.00724 (15)	0.3683 (2)	0.45107 (11)	0.0423 (5)
H8	−0.0652	0.3366	0.4593	0.051*
C9	0.07007 (15)	0.33347 (19)	0.49349 (11)	0.0402 (5)
C10	0.15711 (15)	0.3793 (2)	0.48163 (11)	0.0435 (5)
H10	0.1665	0.4351	0.4475	0.052*
C11	0.22944 (15)	0.3418 (2)	0.52056 (12)	0.0437 (6)
C12	0.21532 (15)	0.2592 (2)	0.57258 (11)	0.0411 (5)
C13	0.12835 (16)	0.2157 (2)	0.58524 (11)	0.0428 (5)
C14	0.05539 (15)	0.2521 (2)	0.54515 (11)	0.0428 (5)
H14	−0.0031	0.2219	0.5530	0.051*
C15	0.33483 (18)	0.4696 (3)	0.46434 (14)	0.0652 (8)
H15A	0.3242	0.4367	0.4206	0.098*
H15B	0.3973	0.4962	0.4677	0.098*
H15C	0.2946	0.5371	0.4717	0.098*
C16	0.3270 (2)	0.3053 (2)	0.65403 (14)	0.0655 (8)
H16A	0.3195	0.3850	0.6355	0.098*
H16B	0.3910	0.2887	0.6599	0.098*
H16C	0.2966	0.3010	0.6965	0.098*
C17	0.03536 (19)	0.0858 (3)	0.65186 (14)	0.0646 (8)
H17A	−0.0098	0.1486	0.6560	0.097*
H17B	0.0387	0.0408	0.6929	0.097*
H17C	0.0186	0.0323	0.6160	0.097*
H1A	−0.1231 (10)	0.4289 (19)	0.3709 (11)	0.050*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0320 (10)	0.0498 (11)	0.0407 (11)	−0.0008 (8)	−0.0063 (8)	0.0046 (8)
N2	0.0349 (10)	0.0496 (10)	0.0385 (11)	0.0046 (8)	−0.0062 (8)	−0.0037 (9)
O1	0.0353 (9)	0.0687 (11)	0.0544 (11)	−0.0083 (8)	−0.0044 (8)	0.0092 (8)
O2	0.0514 (11)	0.0832 (13)	0.0603 (12)	−0.0237 (10)	−0.0062 (8)	0.0223 (10)
O3	0.0411 (9)	0.0797 (12)	0.0457 (10)	−0.0056 (9)	−0.0069 (8)	0.0135 (9)
O4	0.0475 (10)	0.0716 (11)	0.0561 (11)	−0.0065 (8)	−0.0100 (8)	0.0231 (9)
O5	0.0397 (9)	0.0548 (9)	0.0477 (10)	0.0062 (7)	−0.0115 (7)	−0.0020 (8)
O6	0.0359 (9)	0.0830 (12)	0.0548 (11)	−0.0034 (8)	−0.0009 (8)	0.0142 (9)
C1	0.0383 (12)	0.0432 (12)	0.0445 (13)	−0.0004 (9)	0.0003 (10)	0.0051 (10)
C2	0.0321 (11)	0.0461 (12)	0.0371 (12)	0.0001 (9)	0.0016 (9)	0.0015 (10)
C3	0.0340 (12)	0.0543 (13)	0.0411 (13)	−0.0075 (10)	0.0014 (10)	0.0021 (11)
C4	0.0445 (14)	0.0559 (14)	0.0391 (13)	−0.0046 (11)	0.0008 (10)	0.0104 (11)
C5	0.0347 (12)	0.0586 (14)	0.0320 (12)	0.0022 (10)	−0.0010 (9)	−0.0001 (10)
C6	0.0349 (12)	0.0469 (12)	0.0444 (13)	−0.0044 (10)	−0.0017 (10)	0.0005 (11)
C7	0.0305 (11)	0.0465 (12)	0.0417 (13)	−0.0004 (9)	0.0013 (9)	−0.0037 (10)
C8	0.0350 (12)	0.0497 (13)	0.0423 (13)	−0.0002 (10)	−0.0053 (10)	−0.0020 (11)
C9	0.0368 (12)	0.0463 (12)	0.0374 (13)	0.0027 (9)	−0.0051 (10)	−0.0036 (10)
C10	0.0419 (13)	0.0529 (13)	0.0356 (12)	0.0032 (10)	−0.0025 (10)	0.0037 (10)
C11	0.0326 (12)	0.0558 (14)	0.0427 (13)	0.0010 (10)	0.0004 (10)	−0.0020 (11)
C12	0.0354 (12)	0.0479 (12)	0.0399 (13)	0.0062 (10)	−0.0062 (10)	−0.0028 (10)
C13	0.0437 (13)	0.0464 (12)	0.0382 (13)	0.0023 (10)	−0.0032 (10)	0.0016 (10)
C14	0.0338 (12)	0.0519 (13)	0.0428 (13)	−0.0014 (10)	−0.0033 (10)	−0.0012 (11)
C15	0.0477 (16)	0.0815 (19)	0.0664 (18)	−0.0079 (13)	0.0057 (14)	0.0125 (15)
C16	0.0667 (18)	0.0671 (17)	0.0629 (18)	0.0099 (14)	−0.0232 (15)	−0.0177 (14)
C17	0.0556 (16)	0.0703 (17)	0.0678 (18)	−0.0114 (14)	−0.0058 (14)	0.0237 (14)

Geometric parameters (Å, º) top

N1—C7	1.346 (3)	C4—H4	0.9300
N1—N2	1.380 (2)	C5—C6	1.386 (3)
N1—H1A	0.893 (10)	C6—H6	0.9300
N2—C8	1.276 (3)	C8—C9	1.464 (3)
O1—C7	1.243 (2)	C8—H8	0.9300
O2—C3	1.345 (3)	C9—C14	1.385 (3)
O2—H2	0.8200	C9—C10	1.388 (3)
O3—C5	1.351 (3)	C10—C11	1.376 (3)
O3—H3	0.8200	C10—H10	0.9300
O4—C13	1.362 (3)	C11—C12	1.399 (3)
O4—C17	1.415 (3)	C12—C13	1.381 (3)
O5—C12	1.376 (2)	C13—C14	1.393 (3)
O5—C16	1.425 (3)	C14—H14	0.9300
O6—C11	1.362 (3)	C15—H15A	0.9600
O6—C15	1.420 (3)	C15—H15B	0.9600
C1—C6	1.375 (3)	C15—H15C	0.9600
C1—C2	1.400 (3)	C16—H16A	0.9600
C1—H1	0.9300	C16—H16B	0.9600
C2—C3	1.410 (3)	C16—H16C	0.9600
C2—C7	1.462 (3)	C17—H17A	0.9600
C3—C4	1.378 (3)	C17—H17B	0.9600
C4—C5	1.377 (3)	C17—H17C	0.9600

C7—N1—N2	117.54 (17)	C10—C9—C8	120.8 (2)
C7—N1—H1A	122.6 (15)	C11—C10—C9	119.8 (2)
N2—N1—H1A	119.8 (15)	C11—C10—H10	120.1
C8—N2—N1	116.67 (18)	C9—C10—H10	120.1
C3—O2—H2	109.5	O6—C11—C10	125.2 (2)
C5—O3—H3	109.5	O6—C11—C12	114.60 (19)
C13—O4—C17	118.17 (18)	C10—C11—C12	120.2 (2)
C12—O5—C16	114.84 (18)	O5—C12—C13	119.9 (2)
C11—O6—C15	116.89 (19)	O5—C12—C11	120.2 (2)
C6—C1—C2	121.7 (2)	C13—C12—C11	119.9 (2)
C6—C1—H1	119.1	O4—C13—C12	115.19 (19)
C2—C1—H1	119.1	O4—C13—C14	124.9 (2)
C1—C2—C3	117.1 (2)	C12—C13—C14	119.9 (2)
C1—C2—C7	124.0 (2)	C9—C14—C13	119.9 (2)
C3—C2—C7	118.85 (19)	C9—C14—H14	120.1
O2—C3—C4	116.8 (2)	C13—C14—H14	120.1
O2—C3—C2	122.2 (2)	O6—C15—H15A	109.5
C4—C3—C2	121.0 (2)	O6—C15—H15B	109.5
C5—C4—C3	120.3 (2)	H15A—C15—H15B	109.5
C5—C4—H4	119.8	O6—C15—H15C	109.5
C3—C4—H4	119.8	H15A—C15—H15C	109.5
O3—C5—C4	117.2 (2)	H15B—C15—H15C	109.5
O3—C5—C6	122.6 (2)	O5—C16—H16A	109.5
C4—C5—C6	120.1 (2)	O5—C16—H16B	109.5
C1—C6—C5	119.7 (2)	H16A—C16—H16B	109.5
C1—C6—H6	120.2	O5—C16—H16C	109.5
C5—C6—H6	120.2	H16A—C16—H16C	109.5
O1—C7—N1	119.5 (2)	H16B—C16—H16C	109.5
O1—C7—C2	120.3 (2)	O4—C17—H17A	109.5
N1—C7—C2	120.25 (19)	O4—C17—H17B	109.5
N2—C8—C9	119.9 (2)	H17A—C17—H17B	109.5
N2—C8—H8	120.1	O4—C17—H17C	109.5
C9—C8—H8	120.1	H17A—C17—H17C	109.5
C14—C9—C10	120.3 (2)	H17B—C17—H17C	109.5
C14—C9—C8	118.9 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O5ⁱ	0.89 (1)	2.11 (1)	2.953 (2)	157 (2)
O3—H3···N2ⁱⁱ	0.82	2.52	3.214 (3)	143
O3—H3···O1ⁱⁱ	0.82	1.95	2.674 (2)	147
O2—H2···O1	0.82	1.79	2.518 (2)	147

Symmetry codes: (i) x−1/2, −y+1/2, −z+1; (ii) x−1/2, y, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₇H₁₈N₂O₆
M_r	346.33
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	298
a, b, c (Å)	14.601 (1), 11.030 (2), 20.006 (2)
V (Å³)	3222.0 (7)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.20 × 0.20 × 0.20

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.978, 0.978
No. of measured, independent and observed [I > 2σ(I)] reflections	18590, 3520, 2166
R_int	0.069
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.148, 1.03
No. of reflections	3520
No. of parameters	234
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.41, −0.24

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O5ⁱ	0.893 (10)	2.109 (13)	2.953 (2)	157 (2)
O3—H3···N2ⁱⁱ	0.82	2.52	3.214 (3)	143.4
O3—H3···O1ⁱⁱ	0.82	1.95	2.674 (2)	146.6
O2—H2···O1	0.82	1.79	2.518 (2)	146.6

Symmetry codes: (i) x−1/2, −y+1/2, −z+1; (ii) x−1/2, y, −z+1/2.

Acknowledgements

This project is supported by a research grant from Dalian Medical University. We are grateful to Chuan-Xun Li and Qi Zhou for their assistance.

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