organic compounds
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
In the title compound, C16H14N2O2S, the dihedral angle between the benzothiazole ring system and benzene ring is 3.11 (2)°. In the 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); Qu et al. (2007). For the synthetic procedure, see: Stephenson et al., 2007.
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2007); cell SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus; 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).
Supporting information
https://doi.org/10.1107/S1600536809041452/lh2913sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809041452/lh2913Isup2.hkl
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.
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
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)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
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
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.
Data collection: SMART (Bruker, 2007); cell
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).C16H14N2O2S | F(000) = 1248 |
Mr = 298.35 | Dx = 1.382 Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 1634 reflections |
a = 11.9516 (10) Å | θ = 2.3–22.4° |
b = 9.4390 (8) Å | µ = 0.23 mm−1 |
c = 25.418 (2) Å | T = 298 K |
V = 2867.5 (4) Å3 | Block, colorless |
Z = 8 | 0.16 × 0.15 × 0.12 mm |
Bruker SMART CCD diffractometer | 3234 independent reflections |
Radiation source: fine-focus sealed tube | 2156 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.057 |
φ and ω scans | θmax = 27.5°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −15→6 |
Tmin = 0.964, Tmax = 0.973 | k = −11→12 |
12100 measured reflections | l = −31→31 |
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)] = 0.059 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.134 | H 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 parameters | Δρmax = 0.26 e Å−3 |
0 restraints | Δρmin = −0.18 e Å−3 |
C16H14N2O2S | V = 2867.5 (4) Å3 |
Mr = 298.35 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 11.9516 (10) Å | µ = 0.23 mm−1 |
b = 9.4390 (8) Å | T = 298 K |
c = 25.418 (2) Å | 0.16 × 0.15 × 0.12 mm |
Bruker SMART CCD diffractometer | 3234 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2156 reflections with I > 2σ(I) |
Tmin = 0.964, Tmax = 0.973 | Rint = 0.057 |
12100 measured reflections |
R[F2 > 2σ(F2)] = 0.059 | 0 restraints |
wR(F2) = 0.134 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | Δρmax = 0.26 e Å−3 |
3234 reflections | Δρmin = −0.18 e Å−3 |
194 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.36303 (18) | 0.1030 (2) | 0.62901 (9) | 0.0352 (6) | |
C2 | 0.3131 (2) | −0.0017 (3) | 0.71444 (10) | 0.0448 (6) | |
C3 | 0.2757 (3) | −0.0521 (3) | 0.76272 (11) | 0.0604 (8) | |
H3 | 0.2112 | −0.0160 | 0.7783 | 0.072* | |
C4 | 0.3367 (3) | −0.1562 (3) | 0.78658 (11) | 0.0654 (9) | |
H4 | 0.3122 | −0.1932 | 0.8185 | 0.079* | |
C5 | 0.4342 (3) | −0.2081 (3) | 0.76424 (11) | 0.0599 (8) | |
H5 | 0.4747 | −0.2778 | 0.7817 | 0.072* | |
C6 | 0.4720 (2) | −0.1582 (3) | 0.71657 (10) | 0.0483 (7) | |
H6 | 0.5374 | −0.1937 | 0.7017 | 0.058* | |
C7 | 0.4106 (2) | −0.0537 (3) | 0.69110 (10) | 0.0386 (6) | |
C8 | 0.36685 (18) | 0.1881 (2) | 0.58153 (9) | 0.0347 (6) | |
C9 | 0.28533 (19) | 0.2883 (3) | 0.56974 (10) | 0.0408 (6) | |
H9 | 0.2251 | 0.2993 | 0.5926 | 0.049* | |
C10 | 0.2907 (2) | 0.3716 (3) | 0.52558 (10) | 0.0422 (6) | |
H10 | 0.2334 | 0.4357 | 0.5188 | 0.051* | |
C11 | 0.38126 (18) | 0.3618 (2) | 0.49032 (9) | 0.0344 (6) | |
C12 | 0.46109 (19) | 0.2571 (3) | 0.50147 (9) | 0.0409 (6) | |
H12 | 0.5206 | 0.2438 | 0.4784 | 0.049* | |
C13 | 0.45351 (19) | 0.1741 (3) | 0.54534 (10) | 0.0419 (6) | |
H13 | 0.5082 | 0.1059 | 0.5512 | 0.050* | |
C14 | 0.3081 (2) | 0.5541 (2) | 0.43544 (10) | 0.0432 (6) | |
H14A | 0.3419 | 0.6291 | 0.4147 | 0.052* | |
H14B | 0.2804 | 0.5959 | 0.4678 | 0.052* | |
C15 | 0.21108 (19) | 0.4931 (3) | 0.40533 (9) | 0.0368 (6) | |
C16 | 0.4788 (2) | 0.4267 (3) | 0.40869 (11) | 0.0550 (8) | |
H16A | 0.5510 | 0.4252 | 0.4252 | 0.082* | |
H16B | 0.4765 | 0.5013 | 0.3831 | 0.082* | |
H16C | 0.4655 | 0.3374 | 0.3917 | 0.082* | |
N1 | 0.43700 (15) | 0.0080 (2) | 0.64281 (8) | 0.0372 (5) | |
N2 | 0.39284 (16) | 0.4510 (2) | 0.44825 (8) | 0.0421 (5) | |
O1 | 0.13080 (15) | 0.58713 (18) | 0.39831 (8) | 0.0520 (5) | |
H1 | 0.065 (2) | 0.540 (3) | 0.3813 (11) | 0.078* | |
O2 | 0.20655 (15) | 0.37398 (19) | 0.38956 (8) | 0.0583 (5) | |
S1 | 0.25427 (6) | 0.12637 (8) | 0.67437 (3) | 0.0549 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0333 (12) | 0.0360 (14) | 0.0363 (14) | −0.0010 (10) | −0.0001 (11) | −0.0032 (11) |
C2 | 0.0506 (15) | 0.0454 (15) | 0.0384 (15) | 0.0003 (13) | 0.0038 (12) | 0.0027 (13) |
C3 | 0.075 (2) | 0.063 (2) | 0.0438 (18) | −0.0004 (16) | 0.0151 (15) | 0.0044 (16) |
C4 | 0.096 (3) | 0.064 (2) | 0.0361 (17) | −0.0114 (18) | 0.0031 (17) | 0.0104 (15) |
C5 | 0.075 (2) | 0.0537 (19) | 0.0507 (19) | −0.0072 (16) | −0.0165 (17) | 0.0119 (15) |
C6 | 0.0468 (15) | 0.0481 (17) | 0.0500 (18) | −0.0014 (12) | −0.0079 (13) | 0.0083 (14) |
C7 | 0.0409 (13) | 0.0366 (14) | 0.0382 (15) | −0.0057 (11) | −0.0041 (12) | 0.0019 (12) |
C8 | 0.0352 (12) | 0.0349 (13) | 0.0339 (14) | −0.0012 (11) | −0.0016 (11) | 0.0002 (11) |
C9 | 0.0354 (13) | 0.0442 (15) | 0.0429 (16) | 0.0037 (11) | 0.0052 (11) | −0.0003 (13) |
C10 | 0.0396 (13) | 0.0380 (14) | 0.0490 (17) | 0.0071 (11) | −0.0049 (12) | 0.0035 (13) |
C11 | 0.0333 (12) | 0.0351 (13) | 0.0348 (14) | −0.0058 (10) | −0.0085 (10) | −0.0013 (11) |
C12 | 0.0358 (13) | 0.0518 (16) | 0.0351 (15) | 0.0058 (11) | 0.0029 (11) | 0.0043 (12) |
C13 | 0.0371 (13) | 0.0488 (16) | 0.0399 (15) | 0.0107 (11) | −0.0021 (12) | 0.0042 (13) |
C14 | 0.0538 (15) | 0.0338 (14) | 0.0419 (15) | −0.0024 (12) | −0.0093 (13) | 0.0073 (12) |
C15 | 0.0433 (13) | 0.0327 (14) | 0.0345 (14) | −0.0036 (11) | −0.0002 (11) | 0.0057 (11) |
C16 | 0.0535 (16) | 0.0594 (19) | 0.0520 (18) | −0.0068 (14) | 0.0062 (14) | 0.0155 (15) |
N1 | 0.0332 (10) | 0.0386 (12) | 0.0398 (12) | −0.0026 (9) | −0.0011 (9) | 0.0040 (10) |
N2 | 0.0408 (11) | 0.0411 (12) | 0.0444 (13) | 0.0004 (10) | −0.0046 (10) | 0.0112 (10) |
O1 | 0.0432 (10) | 0.0364 (10) | 0.0762 (14) | 0.0012 (8) | −0.0150 (10) | −0.0006 (9) |
O2 | 0.0598 (12) | 0.0422 (12) | 0.0727 (14) | 0.0036 (9) | −0.0132 (11) | −0.0167 (10) |
S1 | 0.0550 (4) | 0.0613 (5) | 0.0484 (5) | 0.0181 (3) | 0.0152 (3) | 0.0110 (4) |
C1—N1 | 1.307 (3) | C10—C11 | 1.408 (3) |
C1—C8 | 1.450 (3) | C10—H10 | 0.9300 |
C1—S1 | 1.752 (2) | C11—N2 | 1.368 (3) |
C2—C3 | 1.390 (3) | C11—C12 | 1.403 (3) |
C2—C7 | 1.397 (3) | C12—C13 | 1.366 (3) |
C2—S1 | 1.730 (3) | C12—H12 | 0.9300 |
C3—C4 | 1.366 (4) | C13—H13 | 0.9300 |
C3—H3 | 0.9300 | C14—N2 | 1.441 (3) |
C4—C5 | 1.386 (4) | C14—C15 | 1.504 (3) |
C4—H4 | 0.9300 | C14—H14A | 0.9700 |
C5—C6 | 1.377 (4) | C14—H14B | 0.9700 |
C5—H5 | 0.9300 | C15—O2 | 1.195 (3) |
C6—C7 | 1.390 (3) | C15—O1 | 1.319 (3) |
C6—H6 | 0.9300 | C16—N2 | 1.456 (3) |
C7—N1 | 1.395 (3) | C16—H16A | 0.9600 |
C8—C9 | 1.391 (3) | C16—H16B | 0.9600 |
C8—C13 | 1.392 (3) | C16—H16C | 0.9600 |
C9—C10 | 1.372 (3) | O1—H1 | 1.00 (3) |
C9—H9 | 0.9300 | ||
N1—C1—C8 | 125.6 (2) | N2—C11—C12 | 121.5 (2) |
N1—C1—S1 | 114.31 (18) | N2—C11—C10 | 122.4 (2) |
C8—C1—S1 | 120.10 (17) | C12—C11—C10 | 116.1 (2) |
C3—C2—C7 | 121.5 (3) | C13—C12—C11 | 121.6 (2) |
C3—C2—S1 | 128.9 (2) | C13—C12—H12 | 119.2 |
C7—C2—S1 | 109.53 (18) | C11—C12—H12 | 119.2 |
C4—C3—C2 | 117.8 (3) | C12—C13—C8 | 122.3 (2) |
C4—C3—H3 | 121.1 | C12—C13—H13 | 118.8 |
C2—C3—H3 | 121.1 | C8—C13—H13 | 118.8 |
C3—C4—C5 | 121.4 (3) | N2—C14—C15 | 113.5 (2) |
C3—C4—H4 | 119.3 | N2—C14—H14A | 108.9 |
C5—C4—H4 | 119.3 | C15—C14—H14A | 108.9 |
C6—C5—C4 | 121.1 (3) | N2—C14—H14B | 108.9 |
C6—C5—H5 | 119.5 | C15—C14—H14B | 108.9 |
C4—C5—H5 | 119.5 | H14A—C14—H14B | 107.7 |
C5—C6—C7 | 118.6 (3) | O2—C15—O1 | 123.7 (2) |
C5—C6—H6 | 120.7 | O2—C15—C14 | 124.4 (2) |
C7—C6—H6 | 120.7 | O1—C15—C14 | 111.9 (2) |
C6—C7—N1 | 125.9 (2) | N2—C16—H16A | 109.5 |
C6—C7—C2 | 119.5 (2) | N2—C16—H16B | 109.5 |
N1—C7—C2 | 114.6 (2) | H16A—C16—H16B | 109.5 |
C9—C8—C13 | 116.3 (2) | N2—C16—H16C | 109.5 |
C9—C8—C1 | 122.3 (2) | H16A—C16—H16C | 109.5 |
C13—C8—C1 | 121.4 (2) | H16B—C16—H16C | 109.5 |
C10—C9—C8 | 122.2 (2) | C1—N1—C7 | 111.7 (2) |
C10—C9—H9 | 118.9 | C11—N2—C14 | 121.4 (2) |
C8—C9—H9 | 118.9 | C11—N2—C16 | 121.0 (2) |
C9—C10—C11 | 121.3 (2) | C14—N2—C16 | 116.5 (2) |
C9—C10—H10 | 119.3 | C15—O1—H1 | 109.4 (16) |
C11—C10—H10 | 119.3 | C2—S1—C1 | 89.89 (12) |
C7—C2—C3—C4 | −0.9 (4) | C10—C11—C12—C13 | −2.9 (3) |
S1—C2—C3—C4 | 179.1 (2) | C11—C12—C13—C8 | −0.1 (4) |
C2—C3—C4—C5 | 1.6 (5) | C9—C8—C13—C12 | 2.2 (4) |
C3—C4—C5—C6 | −1.3 (5) | C1—C8—C13—C12 | −177.3 (2) |
C4—C5—C6—C7 | 0.3 (4) | N2—C14—C15—O2 | −5.5 (4) |
C5—C6—C7—N1 | −179.9 (2) | N2—C14—C15—O1 | 174.4 (2) |
C5—C6—C7—C2 | 0.3 (4) | C8—C1—N1—C7 | 178.9 (2) |
C3—C2—C7—C6 | 0.0 (4) | S1—C1—N1—C7 | 0.4 (3) |
S1—C2—C7—C6 | 180.00 (19) | C6—C7—N1—C1 | 179.8 (2) |
C3—C2—C7—N1 | −179.8 (2) | C2—C7—N1—C1 | −0.4 (3) |
S1—C2—C7—N1 | 0.2 (3) | C12—C11—N2—C14 | 177.0 (2) |
N1—C1—C8—C9 | −179.4 (2) | C10—C11—N2—C14 | −4.5 (3) |
S1—C1—C8—C9 | −1.0 (3) | C12—C11—N2—C16 | 9.8 (3) |
N1—C1—C8—C13 | 0.1 (4) | C10—C11—N2—C16 | −171.8 (2) |
S1—C1—C8—C13 | 178.57 (18) | C15—C14—N2—C11 | −81.0 (3) |
C13—C8—C9—C10 | −1.4 (4) | C15—C14—N2—C16 | 86.8 (3) |
C1—C8—C9—C10 | 178.1 (2) | C3—C2—S1—C1 | 180.0 (3) |
C8—C9—C10—C11 | −1.5 (4) | C7—C2—S1—C1 | 0.00 (19) |
C9—C10—C11—N2 | −174.9 (2) | N1—C1—S1—C2 | −0.23 (19) |
C9—C10—C11—C12 | 3.6 (3) | C8—C1—S1—C2 | −178.8 (2) |
N2—C11—C12—C13 | 175.7 (2) |
D—H···A | D—H | H···A | D···A | 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−1/2, −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 formula | C16H14N2O2S |
Mr | 298.35 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 298 |
a, b, c (Å) | 11.9516 (10), 9.4390 (8), 25.418 (2) |
V (Å3) | 2867.5 (4) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.23 |
Crystal size (mm) | 0.16 × 0.15 × 0.12 |
Data collection | |
Diffractometer | Bruker SMART CCD |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.964, 0.973 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 12100, 3234, 2156 |
Rint | 0.057 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.059, 0.134, 1.06 |
No. of reflections | 3234 |
No. of parameters | 194 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 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).
D—H···A | D—H | H···A | D···A | 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) | 156.4 |
C14—H14A···O2iii | 0.97 | 2.47 | 3.242 (3) | 136.6 |
Symmetry codes: (i) x−1/2, −y+1/2, −z+1; (ii) −x+1/2, −y, z+1/2; (iii) −x+1/2, y+1/2, z. |
References
Bruker (2007). SAINT-Plus and SMART. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Kung, H. F., Lee, C.-W., Zhuang, Z.-P., Kung, M.-P., Hou, C. & Plssl, K. (2001). J. Am. Chem. Soc. 123, 12740–12741. Web of Science CrossRef PubMed CAS Google Scholar
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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).