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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 8| August 2011| Page o2094
doi:10.1107/S1600536811028315

1-[3-(Hy­dr­oxy­meth­yl)phen­yl]-3-phenyl­urea

Hyeong Choi,a Yong Suk Shim,a Byung Hee Han,a Sung Kwon Kanga* and Chang Keun Sungb

aDepartment of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea, and bDepartment of Food Science and Technology, Chungnam National University, Daejeon 305-764, Republic of Korea
*Correspondence e-mail: skkang@cnu.ac.kr

(Received 8 July 2011; accepted 14 July 2011; online 23 July 2011)

In the title compound, C14H14N2O2, the dihedral angle between the benzene rings is 23.6 (1)°. The H atoms of the urea NH groups are positioned syn to each other. In the crystal, inter­molecular N—H⋯O and O—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional network.

Related literature

For general background to melanin, see: Kubo et al. (2000[Kubo, I., Kinst-Hori, I., Chaudhuri, S. K., Kubo, J., Sánchez, Y. & Ogura, T. (2000). Bioorg. Med. Chem. 8, 1749-1755.]); Claus & Decker (2006[Claus, H. & Decker, H. (2006). Syst. Appl. Microbiol. 29, 3-14.]). For the development of tyrosinase inhibitors, see: Khan et al. (2006[Khan, K. M., Maharvi, G. M., Khan, M. T. H., Shaikh, A. J., Perveen, S., Begum, S. & Choudhary, M. I. (2006). Bioorg. Med. Chem. 14, 344—351.]); Kojima et al. (1995[Kojima, S., Yamaguchi, H., Morita, K. & Ueno, Y. (1995). Biol. Pharm. Bull. 18, 1076-1080.]); Cabanes et al. (1994[Cabanes, J., Chazarra, S. & Garcia-Carmona, F. (1994). J. Pharm. Pharmacol. 46, 982-985.]); Casañola-Martin et al. (2006[Casañola-Martin, G. M., Khan, M. T. H., Marrero-Ponce, Y., Ather, A., Sultankhodzhaev, F. & Torrens, F. (2006). Bioorg. Med. Chem. Lett. 16, 324-330.]); Son et al. (2000[Son, S. M., Moon, K. D. & Lee, C. Y. (2000). J. Agric. Food Chem. 48, 2071-2074.]); Hong et al. (2008[Hong, W. K., Heo, J. Y., Han, B. H., Sung, C. K. & Kang, S. K. (2008). Acta Cryst. E64, o49.]); Lee et al. (2007[Lee, C. W., Son, E.-M., Kim, H. S., Xu, P., Batmunkh, T., Lee, B.-J. & Koo, K. A. (2007). Bioorg. Med. Chem. Lett. 17, 5462-5464.]); Yi et al. (2010[Yi, W., Cao, R., Peng, W., Wen, H., Yan, Q., Zhou, B., Ma, L. & Song, H. C. (2010). Eur. J. Med. Chem. 45, 639-646.]); Choi et al. (2010[Choi, H., Lee, T., Han, B. H., Kang, S. K. & Sung, C. K. (2010). Acta Cryst. E66, o2088-o2089.]).

[Scheme 1]

Experimental

Crystal data

  • C14H14N2O2

  • Mr = 242.27

  • Monoclinic, P 21 /c

  • a = 14.6207 (8) Å

  • b = 7.0692 (4) Å

  • c = 12.4019 (5) Å

  • β = 109.818 (3)°

  • V = 1205.90 (11) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 296 K

  • 0.22 × 0.21 × 0.05 mm
Data collection

  • Bruker SMART CCD area-detector diffractometer

  • 9960 measured reflections

  • 2694 independent reflections

  • 1664 reflections with I > 2σ(I)

  • Rint = 0.052
Refinement

  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.111

  • S = 0.93

  • 2694 reflections

  • 175 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.14 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N7—H7⋯O18i 0.87 (2) 2.12 (2) 2.958 (2) 163 (1)
N10—H10⋯O18i 0.90 (2) 2.18 (2) 3.031 (2) 157 (1)
O18—H18⋯O9ii 0.86 (2) 1.91 (2) 2.763 (2) 175 (2)
Symmetry codes: (i) -x+1, -y+1, -z; (ii) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 2002[Bruker (2002). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2002[Bruker (2002). SAINT and SMART. 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: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811028315/im2305sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811028315/im2305Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811028315/im2305Isup3.cml

checkCIF report


Comment top

Melanin plays a major role in human skin protection as well as in undesirable browning of fruits and vegetables (Kubo et al., 2000). Tyrosinase is a key enzyme involved in the first stage of melanin synthesis. Tyrosinase catalyses two distinct reactions involving molecular oxygen, the hydroxylation of tyrosine to L-DOPA as a monophenolase and the oxidation of L-DOPA to dopaquinone as a diphenolase. Dopaquinone is non-enzymatically converted into dopachrome and dihydroxyindols, which induce the production of melanin pigments (Claus & Decker, 2006). Tyrosinase inhibitors have become increasingly important in both agriculture cosmetic industry and medication due to decreasing the excessive accumulation of pigmentation resulting from the enzyme action (Khan et al., 2006). Numerous potential tyrosinase inhibitors have been discovered from natural and synthetic sources, such as ascorbic acid (Kojima et al., 1995), kojic acid (Cabanes et al., 1994), arbutin (Casañola-Martin et al., 2006) and tropolone (Son et al., 2000). They contain aromatic, methoxy, hydroxyl (Hong et al., 2008; Lee et al., 2007), aldehyde (Yi et al., 2010), and amide (Choi et al., 2010) groups in their structure. Nevertheless, some of their individual activities are either not potent enough to be considered of practical use or not compatible with safety regulations for food and cosmetic additives. Therefore, it is still necessary to search and develop novel tyrosinase inhibitors with potent activities and lower side effects. In our continuing search for tyrosinase inhibitors, we have synthesized the title compound, (I), from the reaction of 3-aminobenzyl alcohol and phenyl isocyanate under ambient condition. Here, the crystal sturucture of (I) is described (Fig.1).

The 3-hydroxymethylphenyl moiety is essentially planar with a mean deviation of 0.010 Å from the corresponding least-squares plane defined by the eight constituent atoms. The dihedral angle between the benzene rings is 23.6 (1) °. The presence of intermolecular N—H···O and O—H···O hydrogen bonds link the molecules into a three-dimensional network (Fig. 2, Table 1). The H atoms of the NH groups of urea are positioned syn to each other.

Related literature top

For general background to melanin, see: Kubo et al. (2000); Claus & Decker (2006). For the development of tyrosinase inhibitors, see: Khan et al. (2006); Kojima et al. (1995); Cabanes et al. (1994); Casañola-Martin et al. (2006); Son et al. (2000); Hong et al. (2008); Lee et al. (2007); Yi et al. (2010); Choi et al. (2010).

Experimental top

3-Aminobenzyl alcohol and phenyl isocyanate were purchased from Sigma Chemical Co. Solvents used for organic synthesis were redistilled before use. All other chemicals and solvents were of analytical grade and used without further purification. The title compound was prepared from the reaction of 3-aminobenzyl alcohol (0.2 g, 1.0 mmol) with phenyl isocyanate (0.23 g, 1.2 mmol) in acetonitrile (6 ml) with stirring. The reaction was completed within 30 min at room temperature under 1 atm of N2 gas. The solvents were removed under reduced pressure. The solids collected and washed with dichloromethane. Removal of the solvent gave a white solid (73%, m.p. 446 K). Single crystals were obtained from an ethanolic solution by slow evaporation of the solvent at room temperature.

Refinement top

H atoms of NH and OH groups were located in a difference Fourier map and refined freely. Rremaining H atoms were positioned geometrically and refined using a riding model with C—H = 0.93–0.97 Å, and with Uiso(H) = 1.2Ueq (C) for aromatic and methylene H atoms.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. Molecular structure of (I), showing the atom-numbering scheme and 30% probability ellipsoids.
[Figure 2] Fig. 2. Part of the crystal structure of (I), showing 3-D network of molecules linked by intermolecular N—H···O and O—H···O hydrogen bonds (dashed lines).
1-[3-(Hydroxymethyl)phenyl]-3-phenylurea top
Crystal data top
C14H14N2O2F(000) = 512
Mr = 242.27Dx = 1.334 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2624 reflections
a = 14.6207 (8) Åθ = 3.2–28.0°
b = 7.0692 (4) ŵ = 0.09 mm−1
c = 12.4019 (5) ÅT = 296 K
β = 109.818 (3)°Plate, colourless
V = 1205.90 (11) Å30.22 × 0.21 × 0.05 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer		Rint = 0.052
ϕ and ω scansθmax = 27.5°, θmin = 3.0°
9960 measured reflectionsh = −15→18
2694 independent reflectionsk = −9→6
1664 reflections with I > 2σ(I)l = −16→9
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.041 w = 1/[σ2(Fo2) + (0.0584P)2]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.111(Δ/σ)max < 0.001
S = 0.93Δρmax = 0.14 e Å−3
2694 reflectionsΔρmin = −0.21 e Å−3
175 parameters
Crystal data top
C14H14N2O2V = 1205.90 (11) Å3
Mr = 242.27Z = 4
Monoclinic, P21/cMo Kα radiation
a = 14.6207 (8) ŵ = 0.09 mm−1
b = 7.0692 (4) ÅT = 296 K
c = 12.4019 (5) Å0.22 × 0.21 × 0.05 mm
β = 109.818 (3)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		1664 reflections with I > 2σ(I)
9960 measured reflectionsRint = 0.052
2694 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.111H atoms treated by a mixture of independent and constrained refinement
S = 0.93Δρmax = 0.14 e Å−3
2694 reflectionsΔρmin = −0.21 e Å−3
175 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.13667 (11)0.36148 (19)0.11590 (11)0.0385 (3)
C20.07277 (11)0.2820 (2)0.01677 (13)0.0471 (4)
H20.09330.2595−0.04530.057*
C3−0.02094 (12)0.2359 (2)0.00922 (14)0.0546 (4)
H3−0.06320.1839−0.05810.066*
C4−0.05198 (12)0.2664 (2)0.10023 (15)0.0581 (5)
H4−0.11490.23430.09550.07*
C50.01144 (13)0.3456 (3)0.19916 (15)0.0619 (5)
H5−0.00930.36720.26110.074*
C60.10517 (12)0.3932 (2)0.20757 (12)0.0524 (4)
H60.1470.44640.27480.063*
N70.22912 (9)0.41144 (18)0.11382 (11)0.0442 (3)
H70.2359 (11)0.410 (2)0.0471 (14)0.049 (4)*
C80.31390 (11)0.42001 (18)0.20514 (11)0.0381 (3)
O90.31723 (8)0.41011 (14)0.30535 (8)0.0495 (3)
N100.39322 (9)0.44032 (17)0.17245 (10)0.0436 (3)
H100.3815 (11)0.444 (2)0.0964 (15)0.057 (5)*
C110.49231 (11)0.43970 (18)0.24098 (11)0.0369 (3)
C120.52658 (11)0.44241 (19)0.35949 (12)0.0454 (4)
H120.48340.44280.39990.055*
C130.62598 (12)0.4446 (2)0.41732 (13)0.0516 (4)
H130.64910.44620.4970.062*
C140.69114 (12)0.4444 (2)0.35936 (13)0.0481 (4)
H140.75760.44660.39970.058*
C150.65760 (11)0.44079 (19)0.24059 (12)0.0426 (4)
C160.55875 (11)0.43755 (19)0.18285 (12)0.0423 (4)
H160.53590.43380.10320.051*
C170.72705 (12)0.4432 (2)0.17456 (14)0.0554 (4)
H17A0.79210.46840.22720.066*
H17B0.72760.3190.14150.066*
O180.70325 (8)0.58030 (19)0.08550 (9)0.0559 (3)
H180.6949 (15)0.685 (3)0.1155 (18)0.094 (8)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0402 (9)0.0407 (8)0.0384 (7)0.0035 (6)0.0184 (6)0.0040 (6)
C20.0471 (10)0.0508 (9)0.0476 (8)0.0011 (7)0.0216 (7)−0.0047 (7)
C30.0484 (11)0.0514 (10)0.0634 (10)−0.0044 (8)0.0181 (8)−0.0058 (8)
C40.0434 (11)0.0665 (11)0.0697 (11)0.0000 (8)0.0260 (9)0.0141 (9)
C50.0524 (12)0.0909 (13)0.0525 (10)0.0108 (10)0.0309 (9)0.0147 (9)
C60.0459 (11)0.0747 (11)0.0400 (8)0.0060 (8)0.0190 (7)0.0029 (8)
N70.0395 (8)0.0641 (9)0.0327 (6)−0.0023 (6)0.0169 (6)0.0007 (6)
C80.0433 (9)0.0383 (8)0.0361 (7)−0.0014 (6)0.0176 (6)−0.0006 (6)
O90.0509 (7)0.0673 (7)0.0339 (5)−0.0055 (5)0.0193 (5)−0.0011 (5)
N100.0411 (8)0.0609 (8)0.0315 (6)−0.0035 (6)0.0159 (5)0.0003 (6)
C110.0389 (9)0.0362 (8)0.0353 (7)−0.0021 (6)0.0121 (6)−0.0006 (6)
C120.0494 (11)0.0538 (9)0.0361 (7)−0.0015 (7)0.0185 (7)−0.0032 (7)
C130.0521 (11)0.0638 (11)0.0354 (7)0.0000 (8)0.0103 (7)−0.0011 (7)
C140.0424 (10)0.0532 (10)0.0452 (8)0.0018 (7)0.0103 (7)−0.0009 (7)
C150.0436 (10)0.0410 (8)0.0455 (8)0.0011 (7)0.0181 (7)−0.0005 (6)
C160.0421 (10)0.0507 (9)0.0354 (7)−0.0029 (7)0.0148 (6)−0.0011 (6)
C170.0457 (11)0.0697 (11)0.0539 (9)0.0013 (8)0.0210 (8)−0.0028 (8)
O180.0630 (8)0.0707 (9)0.0428 (6)−0.0048 (6)0.0294 (6)−0.0059 (6)
Geometric parameters (Å, º) top
C1—C61.3820 (19)N10—H100.900 (17)
C1—C21.386 (2)C11—C121.3829 (19)
C1—N71.4058 (19)C11—C161.392 (2)
C2—C31.380 (2)C12—C131.386 (2)
C2—H20.93C12—H120.93
C3—C41.369 (2)C13—C141.374 (2)
C3—H30.93C13—H130.93
C4—C51.381 (2)C14—C151.386 (2)
C4—H40.93C14—H140.93
C5—C61.380 (2)C15—C161.379 (2)
C5—H50.93C15—C171.505 (2)
C6—H60.93C16—H160.93
N7—C81.3678 (19)C17—O181.421 (2)
N7—H70.866 (17)C17—H17A0.97
C8—O91.2291 (15)C17—H17B0.97
C8—N101.3597 (18)O18—H180.86 (2)
N10—C111.4094 (18)
C6—C1—C2118.88 (14)C11—N10—H10115.1 (10)
C6—C1—N7124.41 (14)C12—C11—C16119.05 (14)
C2—C1—N7116.66 (12)C12—C11—N10124.67 (13)
C3—C2—C1120.73 (14)C16—C11—N10116.28 (12)
C3—C2—H2119.6C11—C12—C13119.26 (14)
C1—C2—H2119.6C11—C12—H12120.4
C4—C3—C2120.39 (16)C13—C12—H12120.4
C4—C3—H3119.8C14—C13—C12121.38 (14)
C2—C3—H3119.8C14—C13—H13119.3
C3—C4—C5119.08 (15)C12—C13—H13119.3
C3—C4—H4120.5C13—C14—C15119.84 (15)
C5—C4—H4120.5C13—C14—H14120.1
C6—C5—C4121.08 (15)C15—C14—H14120.1
C6—C5—H5119.5C16—C15—C14118.90 (14)
C4—C5—H5119.5C16—C15—C17119.96 (13)
C5—C6—C1119.84 (15)C14—C15—C17121.13 (14)
C5—C6—H6120.1C15—C16—C11121.56 (13)
C1—C6—H6120.1C15—C16—H16119.2
C8—N7—C1127.08 (12)C11—C16—H16119.2
C8—N7—H7115.2 (10)O18—C17—C15113.44 (13)
C1—N7—H7116.0 (10)O18—C17—H17A108.9
O9—C8—N10124.20 (14)C15—C17—H17A108.9
O9—C8—N7123.29 (13)O18—C17—H17B108.9
N10—C8—N7112.51 (12)C15—C17—H17B108.9
C8—N10—C11128.77 (12)H17A—C17—H17B107.7
C8—N10—H10115.9 (10)C17—O18—H18106.6 (14)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N7—H7···O18i0.87 (2)2.12 (2)2.958 (2)163 (1)
N10—H10···O18i0.90 (2)2.18 (2)3.031 (2)157 (1)
O18—H18···O9ii0.86 (2)1.91 (2)2.763 (2)175 (2)
Symmetry codes: (i) −x+1, −y+1, −z; (ii) −x+1, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formulaC14H14N2O2
Mr242.27
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)14.6207 (8), 7.0692 (4), 12.4019 (5)
β (°) 109.818 (3)
V (Å3)1205.90 (11)
Z4
Radiation typeMo Kα
µ (mm−1)0.09
Crystal size (mm)0.22 × 0.21 × 0.05
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		9960, 2694, 1664
Rint0.052
(sin θ/λ)max (Å−1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.111, 0.93
No. of reflections2694
No. of parameters175
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.14, −0.21

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N7—H7···O18i0.87 (2)2.12 (2)2.958 (2)163 (1)
N10—H10···O18i0.90 (2)2.18 (2)3.031 (2)157 (1)
O18—H18···O9ii0.86 (2)1.91 (2)2.763 (2)175 (2)
Symmetry codes: (i) −x+1, −y+1, −z; (ii) −x+1, y+1/2, −z+1/2.
 

Acknowledgements

This work was undertaked under the `Human Resource Development Center for Economic Region Leading Industry' Project, supported by the Ministry of Education, Science & Technology (MEST) and the National Research Foundation of Korea (NRF). Also, we wish to thank the DBIO company for partial support of this work.

References

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ISSN: 2056-9890
Volume 67| Part 8| August 2011| Page o2094
doi:10.1107/S1600536811028315
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