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

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ISSN: 2056-9890

2-{[4-(1,3-Benzo­thia­zol-2-yl)phen­yl](meth­yl)amino}acetic acid

aSchool of Chemical and Materials Engineering, Huangshi Institute of Technology, Huangshi 435003, People's Republic of China
*Correspondence e-mail: zy0340907@yahoo.com.cn

(Received 23 September 2009; accepted 11 October 2009; online 17 October 2009)

In the title compound, C16H14N2O2S, the dihedral angle between the benzothia­zole ring system and benzene ring is 3.11 (2)°. In the crystal structure, inter­molecular O—H⋯N hydrogen bonds link mol­ecules into chains along [100] and these chains are, in turn, linked into a three-dimensional network via weak inter­molecular C—H⋯O hydrogen bonds.

Related literature

In an effort to develop in vivo β-sheet imaging probes, many derivatives of thio­flavin T, a water-soluble fluorescent dye, have been synthesized and evaluated, see: Kung et al. (2001[Kung, H. F., Lee, C.-W., Zhuang, Z.-P., Kung, M.-P., Hou, C. & Plssl, K. (2001). J. Am. Chem. Soc. 123, 12740-12741.]); Qu et al. (2007[Qu, W., Kung, M.-P., Hou, C., Oya, S. & Kung, H. F. (2007). J. Med. Chem. 50, 3380-3387.]). For the synthetic procedure, see: Stephenson et al., 2007[Stephenson, K. A., Chandra, R., Zhuang, Z.-P., Hou, C., Oya, S., Kung, M.-P. & Kung, H. F. (2007). Bioconjugate Chem. 18, 238-246.].

[Scheme 1]

Experimental

Crystal data
  • C16H14N2O2S

  • Mr = 298.35

  • Orthorhombic, P b c a

  • a = 11.9516 (10) Å

  • b = 9.4390 (8) Å

  • c = 25.418 (2) Å

  • V = 2867.5 (4) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.23 mm−1

  • T = 298 K

  • 0.16 × 0.15 × 0.12 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.964, Tmax = 0.973

  • 12100 measured reflections

  • 3234 independent reflections

  • 2156 reflections with I > 2σ(I)

  • Rint = 0.057

Refinement
  • R[F2 > 2σ(F2)] = 0.059

  • wR(F2) = 0.134

  • S = 1.06

  • 3234 reflections

  • 194 parameters

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

  • Δρmax = 0.26 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯N1i 1.00 (3) 1.71 (3) 2.695 (3) 167 (2)
C4—H4⋯O2ii 0.93 2.50 3.368 (3) 156
C14—H14A⋯O2iii 0.97 2.47 3.242 (3) 137
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}}]; (iii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z].

Data collection: SMART (Bruker, 2007[Bruker (2007). SAINT-Plus and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2007[Bruker (2007). SAINT-Plus and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus; 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: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

Thioflavin T (ThT) as a water-soluble fluorescence dye has been drawing great attention due to its ability to label amyloid fibrils. In an effort to develop in vivo beta-sheet imaging probes, many derivatives of thioflavin T compounds have been synthesized and evaluated (e.g. Kung et al., 2001; Qu et al., 2007). In this context, we have synthesized the title compound and report its crystal structure herein.

In the molecular structure (Fig. 1), the dihedral angle between the benzothiazole unit and benzene ring is 3.11 (2), and the conformation of the substituted methylamino group is defined by the C16—N2—C14—C15 torsion angle of 86.8 (3)°. All bond lengths and bond angles are as expected. In the crystal structure, intermolecular O-H···N hydrogen bonds link molecules into one-dimensional chains and these chains, are in turn linked into a three-dimensional network via weak intermolecular C—H···O hydrogen bonds (Fig. 2).

Related literature top

In an effort to develop in vivo β-sheet imaging probes, many derivatives of thioflavin T, a water-soluble fluorescent dye, have been synthesized and evaluated, see: Kung et al. (2001); Qu et al. (2007). For the synthetic procedure, see: Stephenson et al., 2007.

Experimental top

Compound (I) was synthesized according to the method described by Stephenson et al. (2007). Yellow single crystals suitable for an X-ray diffraction study were obtained by slow evaporation of an methanol solution of the title compound.

Refinement top

All H atoms were placed in idealized positions [C–H=0.96 Å (methyl), 0.97Å (methylene) and 0.93 Å (aromatic)] and included in the refinement in the riding-model approximation, with Uiso(H)= 1.5Ueq(methyl C) and 1.2Ueq(methylene and aromatic C). The H atom bonded to the carboxyl group O atom was found from the difference map. The O—H distance was refined freely with Uiso(H)= 1.5Ueq(O)

Structure description top

Thioflavin T (ThT) as a water-soluble fluorescence dye has been drawing great attention due to its ability to label amyloid fibrils. In an effort to develop in vivo beta-sheet imaging probes, many derivatives of thioflavin T compounds have been synthesized and evaluated (e.g. Kung et al., 2001; Qu et al., 2007). In this context, we have synthesized the title compound and report its crystal structure herein.

In the molecular structure (Fig. 1), the dihedral angle between the benzothiazole unit and benzene ring is 3.11 (2), and the conformation of the substituted methylamino group is defined by the C16—N2—C14—C15 torsion angle of 86.8 (3)°. All bond lengths and bond angles are as expected. In the crystal structure, intermolecular O-H···N hydrogen bonds link molecules into one-dimensional chains and these chains, are in turn linked into a three-dimensional network via weak intermolecular C—H···O hydrogen bonds (Fig. 2).

In an effort to develop in vivo β-sheet imaging probes, many derivatives of thioflavin T, a water-soluble fluorescent dye, have been synthesized and evaluated, see: Kung et al. (2001); Qu et al. (2007). For the synthetic procedure, see: Stephenson et al., 2007.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. Part of the crystal structure of (I) showing hydrogen bonds as dashed lines. Only H atoms involved in hydrogen bonds are shown.
2-{[4-(1,3-Benzothiazol-2-yl)phenyl](methyl)amino}acetic acid top
Crystal data top
C16H14N2O2SF(000) = 1248
Mr = 298.35Dx = 1.382 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 1634 reflections
a = 11.9516 (10) Åθ = 2.3–22.4°
b = 9.4390 (8) ŵ = 0.23 mm1
c = 25.418 (2) ÅT = 298 K
V = 2867.5 (4) Å3Block, colorless
Z = 80.16 × 0.15 × 0.12 mm
Data collection top
Bruker SMART CCD
diffractometer
3234 independent reflections
Radiation source: fine-focus sealed tube2156 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.057
φ and ω scansθmax = 27.5°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 156
Tmin = 0.964, Tmax = 0.973k = 1112
12100 measured reflectionsl = 3131
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)] = 0.059Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.134H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0495P)2]
where P = (Fo2 + 2Fc2)/3
3234 reflections(Δ/σ)max < 0.001
194 parametersΔρmax = 0.26 e Å3
0 restraintsΔρmin = 0.18 e Å3
Crystal data top
C16H14N2O2SV = 2867.5 (4) Å3
Mr = 298.35Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 11.9516 (10) ŵ = 0.23 mm1
b = 9.4390 (8) ÅT = 298 K
c = 25.418 (2) Å0.16 × 0.15 × 0.12 mm
Data collection top
Bruker SMART CCD
diffractometer
3234 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2156 reflections with I > 2σ(I)
Tmin = 0.964, Tmax = 0.973Rint = 0.057
12100 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0590 restraints
wR(F2) = 0.134H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.26 e Å3
3234 reflectionsΔρmin = 0.18 e Å3
194 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
xyzUiso*/Ueq
C10.36303 (18)0.1030 (2)0.62901 (9)0.0352 (6)
C20.3131 (2)0.0017 (3)0.71444 (10)0.0448 (6)
C30.2757 (3)0.0521 (3)0.76272 (11)0.0604 (8)
H30.21120.01600.77830.072*
C40.3367 (3)0.1562 (3)0.78658 (11)0.0654 (9)
H40.31220.19320.81850.079*
C50.4342 (3)0.2081 (3)0.76424 (11)0.0599 (8)
H50.47470.27780.78170.072*
C60.4720 (2)0.1582 (3)0.71657 (10)0.0483 (7)
H60.53740.19370.70170.058*
C70.4106 (2)0.0537 (3)0.69110 (10)0.0386 (6)
C80.36685 (18)0.1881 (2)0.58153 (9)0.0347 (6)
C90.28533 (19)0.2883 (3)0.56974 (10)0.0408 (6)
H90.22510.29930.59260.049*
C100.2907 (2)0.3716 (3)0.52558 (10)0.0422 (6)
H100.23340.43570.51880.051*
C110.38126 (18)0.3618 (2)0.49032 (9)0.0344 (6)
C120.46109 (19)0.2571 (3)0.50147 (9)0.0409 (6)
H120.52060.24380.47840.049*
C130.45351 (19)0.1741 (3)0.54534 (10)0.0419 (6)
H130.50820.10590.55120.050*
C140.3081 (2)0.5541 (2)0.43544 (10)0.0432 (6)
H14A0.34190.62910.41470.052*
H14B0.28040.59590.46780.052*
C150.21108 (19)0.4931 (3)0.40533 (9)0.0368 (6)
C160.4788 (2)0.4267 (3)0.40869 (11)0.0550 (8)
H16A0.55100.42520.42520.082*
H16B0.47650.50130.38310.082*
H16C0.46550.33740.39170.082*
N10.43700 (15)0.0080 (2)0.64281 (8)0.0372 (5)
N20.39284 (16)0.4510 (2)0.44825 (8)0.0421 (5)
O10.13080 (15)0.58713 (18)0.39831 (8)0.0520 (5)
H10.065 (2)0.540 (3)0.3813 (11)0.078*
O20.20655 (15)0.37398 (19)0.38956 (8)0.0583 (5)
S10.25427 (6)0.12637 (8)0.67437 (3)0.0549 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0333 (12)0.0360 (14)0.0363 (14)0.0010 (10)0.0001 (11)0.0032 (11)
C20.0506 (15)0.0454 (15)0.0384 (15)0.0003 (13)0.0038 (12)0.0027 (13)
C30.075 (2)0.063 (2)0.0438 (18)0.0004 (16)0.0151 (15)0.0044 (16)
C40.096 (3)0.064 (2)0.0361 (17)0.0114 (18)0.0031 (17)0.0104 (15)
C50.075 (2)0.0537 (19)0.0507 (19)0.0072 (16)0.0165 (17)0.0119 (15)
C60.0468 (15)0.0481 (17)0.0500 (18)0.0014 (12)0.0079 (13)0.0083 (14)
C70.0409 (13)0.0366 (14)0.0382 (15)0.0057 (11)0.0041 (12)0.0019 (12)
C80.0352 (12)0.0349 (13)0.0339 (14)0.0012 (11)0.0016 (11)0.0002 (11)
C90.0354 (13)0.0442 (15)0.0429 (16)0.0037 (11)0.0052 (11)0.0003 (13)
C100.0396 (13)0.0380 (14)0.0490 (17)0.0071 (11)0.0049 (12)0.0035 (13)
C110.0333 (12)0.0351 (13)0.0348 (14)0.0058 (10)0.0085 (10)0.0013 (11)
C120.0358 (13)0.0518 (16)0.0351 (15)0.0058 (11)0.0029 (11)0.0043 (12)
C130.0371 (13)0.0488 (16)0.0399 (15)0.0107 (11)0.0021 (12)0.0042 (13)
C140.0538 (15)0.0338 (14)0.0419 (15)0.0024 (12)0.0093 (13)0.0073 (12)
C150.0433 (13)0.0327 (14)0.0345 (14)0.0036 (11)0.0002 (11)0.0057 (11)
C160.0535 (16)0.0594 (19)0.0520 (18)0.0068 (14)0.0062 (14)0.0155 (15)
N10.0332 (10)0.0386 (12)0.0398 (12)0.0026 (9)0.0011 (9)0.0040 (10)
N20.0408 (11)0.0411 (12)0.0444 (13)0.0004 (10)0.0046 (10)0.0112 (10)
O10.0432 (10)0.0364 (10)0.0762 (14)0.0012 (8)0.0150 (10)0.0006 (9)
O20.0598 (12)0.0422 (12)0.0727 (14)0.0036 (9)0.0132 (11)0.0167 (10)
S10.0550 (4)0.0613 (5)0.0484 (5)0.0181 (3)0.0152 (3)0.0110 (4)
Geometric parameters (Å, º) top
C1—N11.307 (3)C10—C111.408 (3)
C1—C81.450 (3)C10—H100.9300
C1—S11.752 (2)C11—N21.368 (3)
C2—C31.390 (3)C11—C121.403 (3)
C2—C71.397 (3)C12—C131.366 (3)
C2—S11.730 (3)C12—H120.9300
C3—C41.366 (4)C13—H130.9300
C3—H30.9300C14—N21.441 (3)
C4—C51.386 (4)C14—C151.504 (3)
C4—H40.9300C14—H14A0.9700
C5—C61.377 (4)C14—H14B0.9700
C5—H50.9300C15—O21.195 (3)
C6—C71.390 (3)C15—O11.319 (3)
C6—H60.9300C16—N21.456 (3)
C7—N11.395 (3)C16—H16A0.9600
C8—C91.391 (3)C16—H16B0.9600
C8—C131.392 (3)C16—H16C0.9600
C9—C101.372 (3)O1—H11.00 (3)
C9—H90.9300
N1—C1—C8125.6 (2)N2—C11—C12121.5 (2)
N1—C1—S1114.31 (18)N2—C11—C10122.4 (2)
C8—C1—S1120.10 (17)C12—C11—C10116.1 (2)
C3—C2—C7121.5 (3)C13—C12—C11121.6 (2)
C3—C2—S1128.9 (2)C13—C12—H12119.2
C7—C2—S1109.53 (18)C11—C12—H12119.2
C4—C3—C2117.8 (3)C12—C13—C8122.3 (2)
C4—C3—H3121.1C12—C13—H13118.8
C2—C3—H3121.1C8—C13—H13118.8
C3—C4—C5121.4 (3)N2—C14—C15113.5 (2)
C3—C4—H4119.3N2—C14—H14A108.9
C5—C4—H4119.3C15—C14—H14A108.9
C6—C5—C4121.1 (3)N2—C14—H14B108.9
C6—C5—H5119.5C15—C14—H14B108.9
C4—C5—H5119.5H14A—C14—H14B107.7
C5—C6—C7118.6 (3)O2—C15—O1123.7 (2)
C5—C6—H6120.7O2—C15—C14124.4 (2)
C7—C6—H6120.7O1—C15—C14111.9 (2)
C6—C7—N1125.9 (2)N2—C16—H16A109.5
C6—C7—C2119.5 (2)N2—C16—H16B109.5
N1—C7—C2114.6 (2)H16A—C16—H16B109.5
C9—C8—C13116.3 (2)N2—C16—H16C109.5
C9—C8—C1122.3 (2)H16A—C16—H16C109.5
C13—C8—C1121.4 (2)H16B—C16—H16C109.5
C10—C9—C8122.2 (2)C1—N1—C7111.7 (2)
C10—C9—H9118.9C11—N2—C14121.4 (2)
C8—C9—H9118.9C11—N2—C16121.0 (2)
C9—C10—C11121.3 (2)C14—N2—C16116.5 (2)
C9—C10—H10119.3C15—O1—H1109.4 (16)
C11—C10—H10119.3C2—S1—C189.89 (12)
C7—C2—C3—C40.9 (4)C10—C11—C12—C132.9 (3)
S1—C2—C3—C4179.1 (2)C11—C12—C13—C80.1 (4)
C2—C3—C4—C51.6 (5)C9—C8—C13—C122.2 (4)
C3—C4—C5—C61.3 (5)C1—C8—C13—C12177.3 (2)
C4—C5—C6—C70.3 (4)N2—C14—C15—O25.5 (4)
C5—C6—C7—N1179.9 (2)N2—C14—C15—O1174.4 (2)
C5—C6—C7—C20.3 (4)C8—C1—N1—C7178.9 (2)
C3—C2—C7—C60.0 (4)S1—C1—N1—C70.4 (3)
S1—C2—C7—C6180.00 (19)C6—C7—N1—C1179.8 (2)
C3—C2—C7—N1179.8 (2)C2—C7—N1—C10.4 (3)
S1—C2—C7—N10.2 (3)C12—C11—N2—C14177.0 (2)
N1—C1—C8—C9179.4 (2)C10—C11—N2—C144.5 (3)
S1—C1—C8—C91.0 (3)C12—C11—N2—C169.8 (3)
N1—C1—C8—C130.1 (4)C10—C11—N2—C16171.8 (2)
S1—C1—C8—C13178.57 (18)C15—C14—N2—C1181.0 (3)
C13—C8—C9—C101.4 (4)C15—C14—N2—C1686.8 (3)
C1—C8—C9—C10178.1 (2)C3—C2—S1—C1180.0 (3)
C8—C9—C10—C111.5 (4)C7—C2—S1—C10.00 (19)
C9—C10—C11—N2174.9 (2)N1—C1—S1—C20.23 (19)
C9—C10—C11—C123.6 (3)C8—C1—S1—C2178.8 (2)
N2—C11—C12—C13175.7 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N1i1.00 (3)1.71 (3)2.695 (3)167 (2)
C4—H4···O2ii0.932.503.368 (3)156
C14—H14A···O2iii0.972.473.242 (3)137
Symmetry codes: (i) x1/2, y+1/2, z+1; (ii) x+1/2, y, z+1/2; (iii) x+1/2, y+1/2, z.

Experimental details

Crystal data
Chemical formulaC16H14N2O2S
Mr298.35
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)298
a, b, c (Å)11.9516 (10), 9.4390 (8), 25.418 (2)
V3)2867.5 (4)
Z8
Radiation typeMo Kα
µ (mm1)0.23
Crystal size (mm)0.16 × 0.15 × 0.12
Data collection
DiffractometerBruker SMART CCD
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.964, 0.973
No. of measured, independent and
observed [I > 2σ(I)] reflections
12100, 3234, 2156
Rint0.057
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.059, 0.134, 1.06
No. of reflections3234
No. of parameters194
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.26, 0.18

Computer programs: SMART (Bruker, 2007), SAINT-Plus (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N1i1.00 (3)1.71 (3)2.695 (3)167 (2)
C4—H4···O2ii0.932.503.368 (3)156.4
C14—H14A···O2iii0.972.473.242 (3)136.6
Symmetry codes: (i) x1/2, y+1/2, z+1; (ii) x+1/2, y, z+1/2; (iii) x+1/2, y+1/2, z.
 

References

First citationBruker (2007). SAINT-Plus and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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