The crystal structure of a protected
L-tyrosine, namely
N-acetyl-
L-tyrosine methyl ester monohydrate, C
12H
15NO
4·H
2O, was determined at both 293 (2) and 123 (2) K. The structure exhibits a network of O—H
O and N—H
O hydrogen bonds, in which the water molecule plays a crucial role as an acceptor of one and a donor of two hydrogen bonds. Molecules of water and of the protected
L-tyrosine form hydrogen-bonded layers perpendicular to [001]. C—H
π interactions are observed in the hydrophobic regions of the structure. The structure is similar to that of
N-acetyl-
L-tyrosine ethyl ester monohydrate [Soriano-García (1993).
Acta Cryst. C
49, 96–97].
Supporting information
CCDC references: 665500; 665501
The protected amino acid was purchased from Bachem Chemical Company. Crystals suitable for X-ray structure determination were obtained by vapour diffusion at room temperature between heptane and an acetone solution containing N-acetyl-L-tyrosine ethyl ester and lidocaine in a molar ratio of 1:1. Lidocaine, which was used to provide the correct ionic strength of the solutions, was purchased from Sigma Chemical Company. The diffraction intensity measurements at 293 (2) and 123 (2) K were performed on two different crystals.
Owing to the absence of significant anomalous scattering, Friedel pairs were merged. The absolute configuration of the purchased materials was known. H atoms bonded to N and O atoms were located in difference Fourier maps and included in the refinement without constraints. For the sp2-bound methyl group (C11), the procedure for finding the H atom relied on locating the maximum electron density around the circle representing the locus of possible H-atom positions (Sheldrick, 1997). For this methyl group, C—H distances and C—C—H angles were kept fixed, while the torsion angles were allowed to refine with Uiso(H) set at 1.2Ueq(C11). H atoms attached to other C atoms were included with appropriate geometrical constraints and were treated as riding, with Uiso(H) values of 1.2Ueq of the parent atoms.
For both compounds, data collection: COLLECT (Nonius, 1997); cell refinement: DENZO–SMN (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003), ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Version 1.4; Macrae et al., 2006); software used to prepare material for publication: SHELXL97.
(Ia)
N-Acetyl-
L-tyrosine methyl ester monohydrate
top
Crystal data top
C12H15NO4·H2O | Dx = 1.271 Mg m−3 |
Mr = 255.27 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 2095 reflections |
a = 7.2117 (1) Å | θ = 1.0–30.0° |
b = 12.9868 (3) Å | µ = 0.10 mm−1 |
c = 14.2470 (4) Å | T = 293 K |
V = 1334.33 (5) Å3 | Block, colourless |
Z = 4 | 0.52 × 0.52 × 0.37 mm |
F(000) = 544 | |
Data collection top
Nonius KappaCCD diffractometer | 2223 independent reflections |
Radiation source: fine-focus sealed tube | 1847 reflections with I > 2σ(I) |
Horizontally mounted graphite crystal monochromator | Rint = 0.020 |
Detector resolution: 9 pixels mm-1 | θmax = 30.0°, θmin = 3.2° |
ϕ scans and ο scans to fill asymmetric unit | h = −10→10 |
Absorption correction: multi-scan (DENZO and SCALEPACK; Otwinowski & Minor, 1997) | k = −18→18 |
Tmin = 0.950, Tmax = 0.964 | l = −19→20 |
8443 measured reflections | |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.040 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.101 | w = 1/[σ2(Fo2) + (0.0462P)2 + 0.235P] where P = (Fo2 + 2Fc2)/3 |
S = 1.01 | (Δ/σ)max < 0.001 |
2223 reflections | Δρmax = 0.20 e Å−3 |
181 parameters | Δρmin = −0.16 e Å−3 |
0 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.094 (4) |
Crystal data top
C12H15NO4·H2O | V = 1334.33 (5) Å3 |
Mr = 255.27 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 7.2117 (1) Å | µ = 0.10 mm−1 |
b = 12.9868 (3) Å | T = 293 K |
c = 14.2470 (4) Å | 0.52 × 0.52 × 0.37 mm |
Data collection top
Nonius KappaCCD diffractometer | 2223 independent reflections |
Absorption correction: multi-scan (DENZO and SCALEPACK; Otwinowski & Minor, 1997) | 1847 reflections with I > 2σ(I) |
Tmin = 0.950, Tmax = 0.964 | Rint = 0.020 |
8443 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.101 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.01 | Δρmax = 0.20 e Å−3 |
2223 reflections | Δρmin = −0.16 e Å−3 |
181 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 | x | y | z | Uiso*/Ueq | |
N1 | 0.7140 (2) | 0.48523 (12) | 0.65541 (11) | 0.0346 (3) | |
H1 | 0.794 (4) | 0.4776 (19) | 0.7018 (17) | 0.051 (7)* | |
C1 | 0.7867 (3) | 0.38301 (13) | 0.51672 (12) | 0.0357 (4) | |
O1 | 0.7839 (3) | 0.30420 (10) | 0.56035 (11) | 0.0627 (5) | |
C2 | 0.7818 (3) | 0.49014 (13) | 0.55995 (12) | 0.0318 (4) | |
H2 | 0.6984 | 0.5337 | 0.5229 | 0.038* | |
O2 | 0.7977 (2) | 0.38843 (11) | 0.42440 (10) | 0.0485 (4) | |
C3 | 0.9779 (3) | 0.53656 (14) | 0.55704 (14) | 0.0365 (4) | |
H3A | 1.0595 | 0.4952 | 0.5958 | 0.044* | |
H3B | 1.0240 | 0.5337 | 0.4931 | 0.044* | |
C4 | 0.9842 (3) | 0.64710 (13) | 0.59090 (12) | 0.0335 (4) | |
C5 | 0.9006 (3) | 0.72601 (14) | 0.54091 (14) | 0.0401 (4) | |
H5 | 0.8373 | 0.7107 | 0.4858 | 0.048* | |
C6 | 1.0781 (3) | 0.67253 (15) | 0.67263 (14) | 0.0411 (5) | |
H6 | 1.1365 | 0.6209 | 0.7069 | 0.049* | |
C7 | 0.9094 (3) | 0.82747 (14) | 0.57132 (14) | 0.0400 (4) | |
H7 | 0.8529 | 0.8794 | 0.5366 | 0.048* | |
C8 | 1.0864 (3) | 0.77369 (15) | 0.70432 (13) | 0.0442 (5) | |
H8 | 1.1485 | 0.7892 | 0.7598 | 0.053* | |
C9 | 1.0023 (3) | 0.85107 (13) | 0.65342 (12) | 0.0342 (4) | |
O9 | 1.0160 (2) | 0.94996 (11) | 0.68728 (11) | 0.0459 (4) | |
H9 | 0.967 (5) | 0.994 (2) | 0.646 (2) | 0.073 (9)* | |
C10 | 0.5350 (3) | 0.46506 (15) | 0.67405 (13) | 0.0386 (4) | |
O10 | 0.4177 (2) | 0.45931 (14) | 0.61182 (11) | 0.0530 (4) | |
C11 | 0.4865 (4) | 0.4494 (2) | 0.77528 (15) | 0.0578 (6) | |
H11A | 0.4050 | 0.5035 | 0.7956 | 0.069* | |
H11B | 0.5975 | 0.4505 | 0.8124 | 0.069* | |
H11C | 0.4257 | 0.3841 | 0.7827 | 0.069* | |
C12 | 0.8085 (5) | 0.29253 (19) | 0.37345 (17) | 0.0668 (7) | |
H12A | 0.8159 | 0.3065 | 0.3074 | 0.080* | |
H12B | 0.7000 | 0.2521 | 0.3862 | 0.080* | |
H12C | 0.9169 | 0.2553 | 0.3929 | 0.080* | |
O5 | 0.3430 (3) | 0.41471 (13) | 0.42768 (13) | 0.0555 (5) | |
H5A | 0.335 (5) | 0.357 (3) | 0.425 (2) | 0.081 (11)* | |
H5B | 0.369 (5) | 0.436 (3) | 0.493 (3) | 0.102 (12)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
N1 | 0.0345 (8) | 0.0365 (7) | 0.0329 (7) | −0.0012 (7) | −0.0016 (7) | −0.0013 (6) |
C1 | 0.0384 (9) | 0.0310 (8) | 0.0377 (9) | 0.0013 (8) | −0.0037 (8) | −0.0017 (7) |
O1 | 0.1109 (15) | 0.0289 (6) | 0.0482 (8) | 0.0039 (8) | −0.0003 (10) | 0.0038 (6) |
C2 | 0.0345 (9) | 0.0269 (7) | 0.0340 (8) | 0.0012 (7) | −0.0015 (7) | 0.0006 (6) |
O2 | 0.0726 (10) | 0.0369 (7) | 0.0360 (7) | 0.0030 (7) | −0.0008 (7) | −0.0047 (6) |
C3 | 0.0341 (9) | 0.0329 (8) | 0.0425 (9) | 0.0009 (8) | 0.0025 (8) | −0.0033 (8) |
C4 | 0.0323 (8) | 0.0305 (8) | 0.0376 (8) | −0.0026 (7) | 0.0023 (7) | −0.0002 (7) |
C5 | 0.0441 (10) | 0.0379 (9) | 0.0382 (9) | −0.0017 (8) | −0.0107 (8) | −0.0024 (8) |
C6 | 0.0488 (11) | 0.0344 (9) | 0.0400 (9) | −0.0017 (8) | −0.0089 (9) | 0.0064 (8) |
C7 | 0.0430 (10) | 0.0339 (9) | 0.0431 (10) | 0.0016 (8) | −0.0106 (9) | 0.0032 (8) |
C8 | 0.0561 (12) | 0.0405 (10) | 0.0361 (9) | −0.0080 (9) | −0.0114 (9) | 0.0021 (8) |
C9 | 0.0372 (9) | 0.0314 (8) | 0.0341 (8) | −0.0041 (7) | 0.0006 (8) | −0.0020 (7) |
O9 | 0.0595 (9) | 0.0327 (7) | 0.0454 (7) | −0.0025 (7) | −0.0109 (7) | −0.0049 (6) |
C10 | 0.0391 (10) | 0.0371 (9) | 0.0397 (9) | −0.0006 (8) | 0.0019 (8) | −0.0059 (8) |
O10 | 0.0381 (8) | 0.0717 (10) | 0.0492 (8) | −0.0048 (8) | −0.0050 (7) | −0.0057 (8) |
C11 | 0.0528 (13) | 0.0792 (16) | 0.0415 (10) | −0.0089 (13) | 0.0104 (10) | −0.0077 (11) |
C12 | 0.099 (2) | 0.0503 (12) | 0.0517 (13) | 0.0063 (14) | −0.0051 (14) | −0.0207 (11) |
O5 | 0.0784 (12) | 0.0361 (8) | 0.0519 (9) | −0.0045 (8) | 0.0016 (9) | 0.0004 (7) |
Geometric parameters (Å, º) top
N1—C10 | 1.344 (3) | C6—H6 | 0.9300 |
N1—C2 | 1.447 (2) | C7—C9 | 1.383 (3) |
N1—H1 | 0.88 (3) | C7—H7 | 0.9300 |
C1—O1 | 1.198 (2) | C8—C9 | 1.379 (3) |
C1—O2 | 1.320 (2) | C8—H8 | 0.9300 |
C1—C2 | 1.522 (2) | C9—O9 | 1.375 (2) |
C2—C3 | 1.538 (3) | O9—H9 | 0.89 (3) |
C2—H2 | 0.9800 | C10—O10 | 1.228 (2) |
O2—C12 | 1.444 (2) | C10—C11 | 1.498 (3) |
C3—C4 | 1.515 (2) | C11—H11A | 0.9600 |
C3—H3A | 0.9700 | C11—H11B | 0.9600 |
C3—H3B | 0.9700 | C11—H11C | 0.9600 |
C4—C5 | 1.386 (3) | C12—H12A | 0.9600 |
C4—C6 | 1.387 (3) | C12—H12B | 0.9600 |
C5—C7 | 1.388 (3) | C12—H12C | 0.9600 |
C5—H5 | 0.9300 | O5—H5A | 0.75 (4) |
C6—C8 | 1.391 (3) | O5—H5B | 0.99 (4) |
| | | |
C10—N1—C2 | 121.3 (2) | C8—C6—H6 | 119.4 |
C10—N1—H1 | 117 (2) | C9—C7—C5 | 119.76 (17) |
C2—N1—H1 | 119 (2) | C9—C7—H7 | 120.1 |
O1—C1—O2 | 124.4 (2) | C5—C7—H7 | 120.1 |
O1—C1—C2 | 124.9 (2) | C9—C8—C6 | 119.9 (2) |
O2—C1—C2 | 110.9 (2) | C9—C8—H8 | 120.0 |
N1—C2—C1 | 110.4 (2) | C6—C8—H8 | 120.0 |
N1—C2—C3 | 110.7 (2) | O9—C9—C8 | 117.7 (2) |
C1—C2—C3 | 109.1 (2) | O9—C9—C7 | 122.6 (2) |
N1—C2—H2 | 108.9 | C8—C9—C7 | 119.8 (2) |
C1—C2—H2 | 108.9 | C9—O9—H9 | 110 (2) |
C3—C2—H2 | 108.9 | O10—C10—N1 | 122.1 (2) |
C1—O2—C12 | 117.3 (2) | O10—C10—C11 | 121.7 (2) |
C4—C3—C2 | 113.0 (2) | N1—C10—C11 | 116.2 (2) |
C4—C3—H3A | 109.0 | C10—C11—H11A | 109.5 |
C2—C3—H3A | 109.0 | C10—C11—H11B | 109.5 |
C4—C3—H3B | 109.0 | H11A—C11—H11B | 109.5 |
C2—C3—H3B | 109.0 | C10—C11—H11C | 109.5 |
H3A—C3—H3B | 107.8 | H11A—C11—H11C | 109.5 |
C5—C4—C6 | 117.9 (2) | H11B—C11—H11C | 109.5 |
C5—C4—C3 | 121.6 (2) | O2—C12—H12A | 109.5 |
C6—C4—C3 | 120.5 (2) | O2—C12—H12B | 109.5 |
C4—C5—C7 | 121.4 (2) | H12A—C12—H12B | 109.5 |
C4—C5—H5 | 119.3 | O2—C12—H12C | 109.5 |
C7—C5—H5 | 119.3 | H12A—C12—H12C | 109.5 |
C4—C6—C8 | 121.2 (2) | H12B—C12—H12C | 109.5 |
C4—C6—H6 | 119.4 | H5A—O5—H5B | 110 (3) |
| | | |
C10—N1—C2—C1 | −71.3 (2) | C6—C4—C5—C7 | −0.2 (3) |
C10—N1—C2—C3 | 167.9 (2) | C3—C4—C5—C7 | −178.9 (2) |
O1—C1—C2—N1 | −18.5 (3) | C5—C4—C6—C8 | 0.8 (3) |
O2—C1—C2—N1 | 162.6 (2) | C3—C4—C6—C8 | 179.5 (2) |
O1—C1—C2—C3 | 103.3 (2) | C4—C5—C7—C9 | −0.3 (3) |
O2—C1—C2—C3 | −75.6 (2) | C4—C6—C8—C9 | −0.9 (3) |
O1—C1—O2—C12 | −0.5 (4) | C6—C8—C9—O9 | −179.4 (2) |
C2—C1—O2—C12 | 178.4 (2) | C6—C8—C9—C7 | 0.3 (3) |
N1—C2—C3—C4 | −63.4 (2) | C5—C7—C9—O9 | 180.0 (2) |
C1—C2—C3—C4 | 175.0 (2) | C5—C7—C9—C8 | 0.3 (3) |
C2—C3—C4—C5 | −67.4 (2) | C2—N1—C10—O10 | −6.9 (3) |
C2—C3—C4—C6 | 113.9 (2) | C2—N1—C10—C11 | 172.8 (2) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O9—H9···O5i | 0.89 (3) | 1.82 (3) | 2.707 (2) | 173 (3) |
N1—H1···O9ii | 0.88 (3) | 2.12 (3) | 3.004 (2) | 177 (2) |
O5—H5A···O1iii | 0.75 (4) | 2.14 (4) | 2.880 (2) | 170 (4) |
O5—H5B···O10 | 0.99 (4) | 1.76 (4) | 2.740 (2) | 174 (3) |
C3—H3A···O10iv | 0.97 | 2.63 | 3.417 (3) | 138 |
C8—H8···O1v | 0.93 | 2.62 | 3.503 (2) | 160 |
C11—H11A···O5vi | 0.96 | 2.81 | 3.671 (3) | 150 |
C12—H12C···O10vii | 0.96 | 2.79 | 3.371 (3) | 120 |
C5—H5···Cg1viii | 0.93 | 2.94 | 3.73 (5) | 144 |
Symmetry codes: (i) x+1/2, −y+3/2, −z+1; (ii) −x+2, y−1/2, −z+3/2; (iii) x−1/2, −y+1/2, −z+1; (iv) x+1, y, z; (v) −x+2, y+1/2, −z+3/2; (vi) −x+1/2, −y+1, z+1/2; (vii) x+1/2, −y+1/2, −z+1; (viii) x−1/2, −y+3/2, −z+1. |
(Ib)
N-Acetyl-
L-tyrosine methyl ester monohydrate
top
Crystal data top
C12H15NO4·H2O | Dx = 1.302 Mg m−3 |
Mr = 255.27 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 2646 reflections |
a = 7.1118 (2) Å | θ = 1.0–33.1° |
b = 12.9364 (3) Å | µ = 0.10 mm−1 |
c = 14.1538 (4) Å | T = 123 K |
V = 1302.17 (6) Å3 | Block, colourless |
Z = 4 | 0.40 × 0.37 × 0.25 mm |
F(000) = 544 | |
Data collection top
Nonius KappaCCD diffractometer | 2790 independent reflections |
Radiation source: fine-focus sealed tube | 2605 reflections with I > 2σ(I) |
Horizontally mounted graphite crystal monochromator | Rint = 0.020 |
Detector resolution: 9 pixels mm-1 | θmax = 33.1°, θmin = 3.3° |
ο scans at chi = 55 deg | h = −10→10 |
Absorption correction: multi-scan HKL DENZO and SCALEPACK (Otwinowski & Minor, 1997) | k = −19→19 |
Tmin = 0.961, Tmax = 0.975 | l = −21→21 |
10167 measured reflections | |
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)] = 0.032 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.084 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | w = 1/[σ2(Fo2) + (0.0426P)2 + 0.2619P] where P = (Fo2 + 2Fc2)/3 |
2790 reflections | (Δ/σ)max < 0.001 |
184 parameters | Δρmax = 0.31 e Å−3 |
0 restraints | Δρmin = −0.18 e Å−3 |
Crystal data top
C12H15NO4·H2O | V = 1302.17 (6) Å3 |
Mr = 255.27 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 7.1118 (2) Å | µ = 0.10 mm−1 |
b = 12.9364 (3) Å | T = 123 K |
c = 14.1538 (4) Å | 0.40 × 0.37 × 0.25 mm |
Data collection top
Nonius KappaCCD diffractometer | 2790 independent reflections |
Absorption correction: multi-scan HKL DENZO and SCALEPACK (Otwinowski & Minor, 1997) | 2605 reflections with I > 2σ(I) |
Tmin = 0.961, Tmax = 0.975 | Rint = 0.020 |
10167 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.032 | 0 restraints |
wR(F2) = 0.084 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | Δρmax = 0.31 e Å−3 |
2790 reflections | Δρmin = −0.18 e Å−3 |
184 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 | x | y | z | Uiso*/Ueq | |
N1 | 0.71157 (15) | 0.48699 (7) | 0.65787 (7) | 0.01325 (17) | |
H1 | 0.794 (3) | 0.4817 (15) | 0.7039 (14) | 0.028 (5)* | |
C1 | 0.77991 (17) | 0.38398 (8) | 0.51734 (8) | 0.01321 (19) | |
O1 | 0.77403 (18) | 0.30426 (6) | 0.56186 (7) | 0.0240 (2) | |
C2 | 0.77647 (16) | 0.49188 (8) | 0.56094 (8) | 0.01177 (18) | |
H2 | 0.6892 | 0.5367 | 0.5237 | 0.014* | |
O2 | 0.79393 (15) | 0.38950 (7) | 0.42407 (6) | 0.01828 (17) | |
C3 | 0.97621 (16) | 0.53788 (8) | 0.55674 (8) | 0.01389 (19) | |
H3A | 1.0611 | 0.4955 | 0.5964 | 0.017* | |
H3B | 1.0226 | 0.5345 | 0.4909 | 0.017* | |
C4 | 0.98391 (16) | 0.64882 (8) | 0.59029 (8) | 0.01260 (18) | |
C5 | 0.89806 (17) | 0.72820 (8) | 0.53906 (8) | 0.0151 (2) | |
H5 | 0.8327 | 0.7121 | 0.4824 | 0.018* | |
C6 | 1.07879 (18) | 0.67465 (8) | 0.67320 (8) | 0.0156 (2) | |
H6 | 1.1384 | 0.6217 | 0.7088 | 0.019* | |
C7 | 0.90651 (17) | 0.83047 (8) | 0.56958 (9) | 0.0149 (2) | |
H7 | 0.8476 | 0.8835 | 0.5338 | 0.018* | |
C8 | 1.08802 (19) | 0.77652 (8) | 0.70499 (8) | 0.0164 (2) | |
H8 | 1.1527 | 0.7926 | 0.7618 | 0.020* | |
C9 | 1.00179 (16) | 0.85473 (8) | 0.65288 (8) | 0.01301 (18) | |
O9 | 1.01535 (14) | 0.95384 (6) | 0.68652 (6) | 0.01733 (17) | |
H9 | 0.967 (4) | 1.0001 (19) | 0.6502 (18) | 0.049 (7)* | |
C10 | 0.53053 (17) | 0.46497 (8) | 0.67793 (8) | 0.0144 (2) | |
O10 | 0.40919 (13) | 0.45748 (8) | 0.61595 (7) | 0.02064 (18) | |
C11 | 0.4846 (2) | 0.44935 (11) | 0.78070 (9) | 0.0221 (2) | |
H11A | 0.4006 | 0.5047 | 0.8021 | 0.027* | |
H11B | 0.6008 | 0.4509 | 0.8179 | 0.027* | |
H11C | 0.4225 | 0.3824 | 0.7891 | 0.027* | |
C12 | 0.8035 (2) | 0.29199 (10) | 0.37386 (10) | 0.0257 (3) | |
H12A | 0.8135 | 0.3052 | 0.3059 | 0.031* | |
H12B | 0.6895 | 0.2517 | 0.3866 | 0.031* | |
H12C | 0.9139 | 0.2531 | 0.3952 | 0.031* | |
O5 | 0.34119 (15) | 0.41298 (7) | 0.43062 (7) | 0.02093 (19) | |
H5B | 0.360 (4) | 0.4303 (17) | 0.4900 (19) | 0.048 (7)* | |
H5A | 0.330 (4) | 0.352 (2) | 0.4296 (19) | 0.049 (7)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
N1 | 0.0143 (4) | 0.0153 (4) | 0.0102 (4) | −0.0004 (3) | −0.0009 (3) | −0.0006 (3) |
C1 | 0.0150 (4) | 0.0122 (4) | 0.0125 (4) | 0.0004 (4) | −0.0014 (4) | −0.0008 (3) |
O1 | 0.0430 (6) | 0.0115 (3) | 0.0176 (4) | 0.0017 (4) | 0.0005 (4) | 0.0014 (3) |
C2 | 0.0140 (4) | 0.0106 (4) | 0.0107 (4) | 0.0002 (3) | −0.0003 (4) | −0.0002 (3) |
O2 | 0.0281 (4) | 0.0149 (3) | 0.0118 (3) | 0.0013 (3) | −0.0008 (4) | −0.0020 (3) |
C3 | 0.0139 (4) | 0.0125 (4) | 0.0152 (4) | 0.0000 (4) | 0.0010 (4) | −0.0014 (3) |
C4 | 0.0135 (4) | 0.0120 (4) | 0.0123 (4) | −0.0012 (4) | 0.0007 (4) | 0.0000 (3) |
C5 | 0.0171 (5) | 0.0144 (4) | 0.0139 (5) | −0.0003 (4) | −0.0043 (4) | −0.0012 (4) |
C6 | 0.0197 (5) | 0.0133 (4) | 0.0137 (5) | −0.0008 (4) | −0.0031 (4) | 0.0022 (3) |
C7 | 0.0168 (5) | 0.0136 (4) | 0.0144 (5) | 0.0008 (4) | −0.0032 (4) | 0.0000 (4) |
C8 | 0.0227 (5) | 0.0143 (4) | 0.0122 (4) | −0.0020 (4) | −0.0042 (4) | 0.0008 (3) |
C9 | 0.0146 (4) | 0.0124 (4) | 0.0121 (4) | −0.0016 (4) | 0.0002 (4) | −0.0006 (3) |
O9 | 0.0240 (4) | 0.0120 (3) | 0.0161 (4) | −0.0002 (3) | −0.0051 (4) | −0.0020 (3) |
C10 | 0.0154 (5) | 0.0138 (4) | 0.0141 (4) | 0.0001 (4) | 0.0014 (4) | −0.0027 (4) |
O10 | 0.0159 (4) | 0.0283 (4) | 0.0177 (4) | −0.0017 (4) | −0.0020 (3) | −0.0022 (4) |
C11 | 0.0210 (5) | 0.0321 (6) | 0.0133 (5) | −0.0034 (5) | 0.0039 (5) | −0.0021 (5) |
C12 | 0.0393 (8) | 0.0202 (5) | 0.0175 (5) | 0.0029 (5) | −0.0019 (6) | −0.0081 (4) |
O5 | 0.0320 (5) | 0.0137 (4) | 0.0171 (4) | −0.0025 (3) | 0.0009 (4) | −0.0002 (3) |
Geometric parameters (Å, º) top
N1—C10 | 1.349 (2) | C6—H6 | 0.9500 |
N1—C2 | 1.449 (2) | C7—C9 | 1.396 (2) |
N1—H1 | 0.88 (2) | C7—H7 | 0.9500 |
C1—O1 | 1.209 (1) | C8—C9 | 1.394 (2) |
C1—O2 | 1.326 (1) | C8—H8 | 0.9500 |
C1—C2 | 1.526 (1) | C9—O9 | 1.371 (1) |
C2—C3 | 1.541 (2) | O9—H9 | 0.86 (3) |
C2—H2 | 1.0000 | C10—O10 | 1.234 (2) |
O2—C12 | 1.449 (1) | C10—C11 | 1.504 (2) |
C3—C4 | 1.513 (2) | C11—H11A | 0.9800 |
C3—H3A | 0.9900 | C11—H11B | 0.9800 |
C3—H3B | 0.9900 | C11—H11C | 0.9800 |
C4—C6 | 1.394 (2) | C12—H12A | 0.9800 |
C4—C5 | 1.398 (2) | C12—H12B | 0.9800 |
C5—C7 | 1.393 (2) | C12—H12C | 0.9800 |
C5—H5 | 0.9500 | O5—H5B | 0.88 (3) |
C6—C8 | 1.394 (2) | O5—H5A | 0.79 (3) |
| | | |
C10—N1—C2 | 120.8 (1) | C4—C6—H6 | 119.3 |
C10—N1—H1 | 118 (1) | C5—C7—C9 | 119.8 (1) |
C2—N1—H1 | 120 (1) | C5—C7—H7 | 120.1 |
O1—C1—O2 | 124.6 (1) | C9—C7—H7 | 120.1 |
O1—C1—C2 | 124.7 (1) | C9—C8—C6 | 119.6 (1) |
O2—C1—C2 | 110.8 (1) | C9—C8—H8 | 120.2 |
N1—C2—C1 | 110.4 (1) | C6—C8—H8 | 120.2 |
N1—C2—C3 | 110.3 (1) | O9—C9—C8 | 117.7 (1) |
C1—C2—C3 | 108.8 (1) | O9—C9—C7 | 122.5 (1) |
N1—C2—H2 | 109.1 | C8—C9—C7 | 119.8 (1) |
C1—C2—H2 | 109.1 | C9—O9—H9 | 114 (2) |
C3—C2—H2 | 109.1 | O10—C10—N1 | 122.3 (1) |
C1—O2—C12 | 116.4 (1) | O10—C10—C11 | 121.7 (1) |
C4—C3—C2 | 112.8 (1) | N1—C10—C11 | 116.0 (1) |
C4—C3—H3A | 109.0 | C10—C11—H11A | 109.5 |
C2—C3—H3A | 109.0 | C10—C11—H11B | 109.5 |
C4—C3—H3B | 109.0 | H11A—C11—H11B | 109.5 |
C2—C3—H3B | 109.0 | C10—C11—H11C | 109.5 |
H3A—C3—H3B | 107.8 | H11A—C11—H11C | 109.5 |
C6—C4—C5 | 118.2 (1) | H11B—C11—H11C | 109.5 |
C6—C4—C3 | 120.6 (1) | O2—C12—H12A | 109.5 |
C5—C4—C3 | 121.2 (1) | O2—C12—H12B | 109.5 |
C7—C5—C4 | 121.2 (1) | H12A—C12—H12B | 109.5 |
C7—C5—H5 | 119.4 | O2—C12—H12C | 109.5 |
C4—C5—H5 | 119.4 | H12A—C12—H12C | 109.5 |
C8—C6—C4 | 121.4 (1) | H12B—C12—H12C | 109.5 |
C8—C6—H6 | 119.3 | H5A—O5—H5B | 107 (2) |
| | | |
C10—N1—C2—C1 | −70.3 (1) | C6—C4—C5—C7 | 0.0 (2) |
C10—N1—C2—C3 | 169.4 (1) | C3—C4—C5—C7 | −179.5 (1) |
O1—C1—C2—N1 | −16.5 (2) | C5—C4—C6—C8 | 0.3 (2) |
O2—C1—C2—N1 | 164.8 (1) | C3—C4—C6—C8 | 179.7 (1) |
O1—C1—C2—C3 | 104.7 (1) | C4—C5—C7—C9 | −0.2 (2) |
O2—C1—C2—C3 | −74.1 (1) | C4—C6—C8—C9 | −0.4 (2) |
O1—C1—O2—C12 | −0.3 (2) | C6—C8—C9—O9 | −179.6 (1) |
C2—C1—O2—C12 | 178.5 (1) | C6—C8—C9—C7 | 0.2 (2) |
N1—C2—C3—C4 | −64.0 (1) | C5—C7—C9—O9 | 179.9 (1) |
C1—C2—C3—C4 | 174.8 (1) | C5—C7—C9—C8 | 0.1 (2) |
C2—C3—C4—C6 | 112.9 (1) | C2—N1—C10—O10 | −6.8 (2) |
C2—C3—C4—C5 | −67.6 (1) | C2—N1—C10—C11 | 172.9 (1) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O9—H9···O5i | 0.86 (3) | 1.83 (3) | 2.693 (1) | 173 (3) |
N1—H1···O9ii | 0.88 (2) | 2.09 (2) | 2.968 (1) | 174 (2) |
O5—H5A···O1iii | 0.79 (3) | 2.07 (3) | 2.853 (1) | 173 (3) |
O5—H5B···O10 | 0.88 (3) | 1.85 (3) | 2.729 (1) | 176 (2) |
C3—H3A···O10iv | 0.99 | 2.54 | 3.356 (2) | 140 |
C8—H8···O1v | 0.95 | 2.55 | 3.462 (2) | 160 |
C11—H11A···O5vi | 0.98 | 2.72 | 3.612 (2) | 151 |
C12—H12C···O10vii | 0.98 | 2.73 | 3.317 (2) | 119 |
C5—H5···Cg1viii | 0.95 | 2.84 | 3.65 (4) | 144 |
Symmetry codes: (i) x+1/2, −y+3/2, −z+1; (ii) −x+2, y−1/2, −z+3/2; (iii) x−1/2, −y+1/2, −z+1; (iv) x+1, y, z; (v) −x+2, y+1/2, −z+3/2; (vi) −x+1/2, −y+1, z+1/2; (vii) x+1/2, −y+1/2, −z+1; (viii) x−1/2, −y+3/2, −z+1. |
Experimental details
| (Ia) | (Ib) |
Crystal data |
Chemical formula | C12H15NO4·H2O | C12H15NO4·H2O |
Mr | 255.27 | 255.27 |
Crystal system, space group | Orthorhombic, P212121 | Orthorhombic, P212121 |
Temperature (K) | 293 | 123 |
a, b, c (Å) | 7.2117 (1), 12.9868 (3), 14.2470 (4) | 7.1118 (2), 12.9364 (3), 14.1538 (4) |
V (Å3) | 1334.33 (5) | 1302.17 (6) |
Z | 4 | 4 |
Radiation type | Mo Kα | Mo Kα |
µ (mm−1) | 0.10 | 0.10 |
Crystal size (mm) | 0.52 × 0.52 × 0.37 | 0.40 × 0.37 × 0.25 |
|
Data collection |
Diffractometer | Nonius KappaCCD diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | Multi-scan (DENZO and SCALEPACK; Otwinowski & Minor, 1997) | Multi-scan HKL DENZO and SCALEPACK (Otwinowski & Minor, 1997) |
Tmin, Tmax | 0.950, 0.964 | 0.961, 0.975 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8443, 2223, 1847 | 10167, 2790, 2605 |
Rint | 0.020 | 0.020 |
(sin θ/λ)max (Å−1) | 0.704 | 0.769 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.101, 1.01 | 0.032, 0.084, 1.00 |
No. of reflections | 2223 | 2790 |
No. of parameters | 181 | 184 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.20, −0.16 | 0.31, −0.18 |
Selected geometric parameters (Å, º) for (Ia) topN1—C10 | 1.344 (3) | C2—C3 | 1.538 (3) |
N1—C2 | 1.447 (2) | O2—C12 | 1.444 (2) |
C1—O1 | 1.198 (2) | C10—O10 | 1.228 (2) |
C1—C2 | 1.522 (2) | | |
| | | |
N1—C2—C1 | 110.4 (2) | C1—C2—C3 | 109.1 (2) |
N1—C2—C3 | 110.7 (2) | C1—O2—C12 | 117.3 (2) |
| | | |
O1—C1—C2—N1 | −18.5 (3) | O1—C1—C2—C3 | 103.3 (2) |
O2—C1—C2—N1 | 162.6 (2) | O2—C1—C2—C3 | −75.6 (2) |
Hydrogen-bond geometry (Å, º) for (Ia) top
D—H···A | D—H | H···A | D···A | D—H···A |
O9—H9···O5i | 0.89 (3) | 1.82 (3) | 2.707 (2) | 173 (3) |
N1—H1···O9ii | 0.88 (3) | 2.12 (3) | 3.004 (2) | 177 (2) |
O5—H5A···O1iii | 0.75 (4) | 2.14 (4) | 2.880 (2) | 170 (4) |
O5—H5B···O10 | 0.99 (4) | 1.76 (4) | 2.740 (2) | 174 (3) |
C3—H3A···O10iv | 0.97 | 2.63 | 3.417 (3) | 138 |
C8—H8···O1v | 0.93 | 2.62 | 3.503 (2) | 160 |
C5—H5···Cg1vi | 0.93 | 2.94 | 3.73 (5) | 144 |
Symmetry codes: (i) x+1/2, −y+3/2, −z+1; (ii) −x+2, y−1/2, −z+3/2; (iii) x−1/2, −y+1/2, −z+1; (iv) x+1, y, z; (v) −x+2, y+1/2, −z+3/2; (vi) x−1/2, −y+3/2, −z+1. |
Selected geometric parameters (Å, º) for (Ib) topN1—C10 | 1.349 (2) | C2—C3 | 1.541 (2) |
N1—C2 | 1.449 (2) | O2—C12 | 1.449 (1) |
C1—O1 | 1.209 (1) | C10—O10 | 1.234 (2) |
C1—C2 | 1.526 (1) | | |
| | | |
N1—C2—C1 | 110.4 (1) | C1—C2—C3 | 108.8 (1) |
N1—C2—C3 | 110.3 (1) | C1—O2—C12 | 116.4 (1) |
| | | |
O1—C1—C2—N1 | −16.5 (2) | O1—C1—C2—C3 | 104.7 (1) |
O2—C1—C2—N1 | 164.8 (1) | O2—C1—C2—C3 | −74.1 (1) |
Hydrogen-bond geometry (Å, º) for (Ib) top
D—H···A | D—H | H···A | D···A | D—H···A |
O9—H9···O5i | 0.86 (3) | 1.83 (3) | 2.693 (1) | 173 (3) |
N1—H1···O9ii | 0.88 (2) | 2.09 (2) | 2.968 (1) | 174 (2) |
O5—H5A···O1iii | 0.79 (3) | 2.07 (3) | 2.853 (1) | 173 (3) |
O5—H5B···O10 | 0.88 (3) | 1.85 (3) | 2.729 (1) | 176 (2) |
C3—H3A···O10iv | 0.99 | 2.54 | 3.356 (2) | 140 |
C8—H8···O1v | 0.95 | 2.55 | 3.462 (2) | 160 |
C5—H5···Cg1vi | 0.95 | 2.84 | 3.65 (4) | 144 |
Symmetry codes: (i) x+1/2, −y+3/2, −z+1; (ii) −x+2, y−1/2, −z+3/2; (iii) x−1/2, −y+1/2, −z+1; (iv) x+1, y, z; (v) −x+2, y+1/2, −z+3/2; (vi) x−1/2, −y+3/2, −z+1. |
Table 5. A comparison of torsion angles (°) describing the conformation of backbones in L-tyrosine derivatives. topϕ, ψ, χ, ω are defined in agreement with IUPAC–IUB Commission on Biochemical Nomenclature (1970). |
Torsion angle | Symbol | AcYOMe (Ia) | AcYOMe (Ib) | AcYOEta | AcYOEtb | AcYOEtc | GYAd | LYL(b)e | VYVf | Yg | Y·HClh |
C2—N1—C10—C11 | ω | 172.8 (2) | 172.9 (1) | 174.6 (4) | -174.3 | -174.7 | 172.8 | 175.3 | -172.0 | — | — |
C1—C2—N1—C10 | ϕ | -71.3 (2) | -70.3 (1) | -74.8 (5) | 75.1 | 74.2 | -119.0 | -82.8 | -83.4 | — | — |
O1—C1—C2—N1 | ψ1 | -18.5 (3) | -16.5 (2) | -17.2 (5) | 16.4 | 13.3 | -61.6 | -46.3 | -37.3 | -14.2 | -31.8 |
O2—C1—C2—N1* | ψ2 | 162.6 (2) | 164.8 (1) | 164.0 (4) | -164.0 | -167.0 | 120.0 | 137.3 | 145.7 | 166.3 | 151.1 |
N1—C2—C3—C4 | χ1 | -63.5 (2) | -64.0 (1) | -61.7 (5) | 62.3 | 63.0 | -86.4 | -76.8 | -64.3 | 69.1 | -178.1 |
C1—C2—C3—C4 | χ2 | 175.0 (1) | 174.8 (1) | 175.5 (4) | -175.3 | -174.8 | 154.3 | 162.8 | 172.9 | -53.1 | 62.8 |
C2—C3—C4—C5 | — | -67.5 (2) | -67.7 (1) | -63.2 (5) | 62.9 | 64.6 | -112.9 | -71.2 | -66.1 | -86.0 | -113.7 |
* Equivalent to N2—C1—C2—N1 in tripepetides.
References: (Ia) and (Ib) this work; (a) N-acetyl-L-tyrosine ethyl ester (Soriano-García, 1993); N-acetyl-L-tyrosine ethyl ester (b) at room temperature and (c) at 110 K (Dahaoui et al., 1999) [notice the opposite sequence of torsion angle signs, which indicates the opposite configuration at Cα; indeed, the deposited data for N-acetyl-L-tyrosine ethyl ester [Cambridge Structural Database (Allen, 2002; Version 5.28) refcodes ATYREE02 and ATYREE03] concern the N-acetyl-(D)-tyrosine ethyl ester structural model); (d) glycyl-L-tyrosyl-L-alanine dihydrate (Eggleston & Baures, 1992); (e) L-leucyl-L-tyrosyl-L-leucine monohydrate (Wu et al., 1987); (f)(D)-valyl-L-tyrosyl-L-valine dihydrate (Mishnev et al., 1978); (g) L-tyrosine; (h) L-tyrosine hydrochloride (Frey et al., 1973). |
The N-acetyl methyl ester of L-tyrosine was chosen from among amino acid residues that are responsible for binding the antiarrhythmics of class I and III in sodium and potassium channels, respectively (Tseng, 2001), and was used in some experiments performed to reveal the mutual chemical recognition of antiarrhythmic agents by amino acids. The crystal structure of teh title compound, L-AcYOMe·H2O, (I), was determined to allow comparison with the structures of N-acetyl-L-tyrosine ethyl ester monohydrate (Pieret et al., 1972; Soriano-García, 1993), L-tyrosine and L-tyrosine hydrochloride (Frey et al., 1973). Charge density studies have also been performed on N-acetyl-L-tyrosine ethyl ester monohydrate (Dahaoui et al., 1999).
Compound (I) crystallizes in space group P212121, and the contents of the asymmetric unit at 123 (2) K are shown in Fig. 1. Selected geometric parameters at 293 (2) K, (Ia), and at 123 (2) K, (Ib), are given in Tables 1 and 3, respectively. In relation to L-tyrosine itself, the protected amino acid offers different possibilities of intermolecular interactions, which are closer to the specific interactions of small peptides. Owing to the inactivation of the amino and carboxyl groups, the water molecule can participate in a network of hydrogen bonds as an acceptor of one H atom and a donor of two. Water molecules and L-AcYOMe molecules form layers parallel to ab at z = 1/2 (Fig. 2, and Tables 2 and 4). Each layer consists of alternating hydrophobic and hydrophilic areas. In the hydrophobic area, C—H···π interactions of type III in the classification by Malone et al. (1997) dominate [C5—H5···Cg1(x − 1/2, −y + 3/2, −z + 1), where Cg1 is the centre of gravity of the C4–C9 benzene ring], whereas in the hydrophilic area, mainly O—H···O hydrogen bonds exist. There are weak C3—H3A···O10(x + 1, y, z) interactions between hydrophobic and hydrophilic areas of the layers. The layers are linked by N—H···O hydrogen bonds, and between hydrophobic and hydrophilic areas of neighbouring layers there are weak C8—H8···O1(−x + 2, y + 1/2, −z + 3/2) interactions (Fig. 3, and Tables 2 and 4). There is no obvious difference in molecular geometry between 293 and 123 K, except for the apparent elongation of bond lengths at the lower temperature due to a reduction in librational effects as the atomic displacements decrease.
Table 5 presents a comparison of the torsion angles that characterize the backbone conformation of (I), N-acetyl-L-tyrosine ethyl ester (Soriano-García, 1993), and N-acetyl-L-tyrosine ethyl ester at room- and low-temperature (Dahaoui et al., 1999) with the conformation of the L-tyrosine residue in selected tripeptides and with the conformation of L-tyrosine itself and L-tyrosine hydrochloride (Frey et al., 1973). The values of the torsion angles ω, ϕ, ψ1, ψ2, χ1 and χ2, which are defined in accordance with the IUPAC–IUB Commission on Biochemical Nomenclature (1970), are similar for protected L-tyrosine; the observed differences in torsion angles are in the range 0.7–5.2°. For tripeptides LYL and VYV, the differences are of up to 25°, indicating that the conformation of the L-tyrosine residue is, in general, well preserved with small deviations caused by the N– and C-ends forming hydrogen bonds. However, in both LYL and VYV, the presence of relatively long hydrocarbon chains of L or V residues provides steric hindrance for such intermolecular interactions. In GYA, owing to a lack of hydrocarbon chains, the N– and C-ends are free to form hydrogen bonds. The moderate N—H···O hydrogen bonds could change the torsion angles of the L-tyrosine residue by 50°. In the cases of L-tyrosine and its hydrochloride, the most pronounced conformational differences arise because of specific patterns of hydrogen bonding.
##AUTHOR: In the paragraph above, please define the residue symbols L, V, Y, A, G.