organic compounds
Methyl (1-benzamido-2-methoxy-2-oxoethyl)tryptophanate
aFormation Doctorale Molécules Bioactives, Santé et Biotechnologies, Centre d'études Doctorales Sciences et Technologies LCO, Faculté des Sciences Dhar El Marhaz, Fès, Morocco, bLaboratoire de Chimie Organique, Faculté des Sciences Dhar el Mahraz, Université Sidi Mohammed Ben Abdellah, Fès, Morocco, and cLaboratoire de Chimie des Matériaux et Biotechnologie des Produits Naturels, E.Ma.Me.P.S., Université Moulay Ismail, Faculté des Sciences, Meknès, Morocco
*Correspondence e-mail: anouar.alami@usmba.ac.ma
The title molecule, C22H23N3O2, is U-shaped, with a dihedral angle of 80.76 (9)° between the indole ring system and the phenyl ring. In the crystal, N—H⋯O hydrogen bonds combine with N—H⋯π and C—H⋯π interactions to generate a three-dimensional structure.
Keywords: crystal structure; indole; benzamido; hydrogen bonds.
CCDC reference: 1573006
Structure description
The molecule of the title compound is approximately U-shaped, Fig. 1, with the indole ring system and the benzene ring linked by a complex alaninate chain and with a dihedral angle of 80.76 (9)° between them. This conformation is supported by an intramolecular C5—H5⋯Cg3 interaction (Table 1).
In the crystal, classical N3—H3N⋯O1 hydrogen bonds together with unusual intermolecular N2—H2N⋯Cg2 contacts and C20—H20⋯Cg1 interactions combine to generate a three dimensional network, Fig. 2.
Synthesis and crystallization
To a solution of 2.6 mmol of N-protected methyl α-azidoglycinate and 3.12 mmol of di-isopropylethylamine (DIEA) in 10 ml of acetone, 2.86 mmol of 2-amino-3-(1H-indol-3-yl)propanoate was added. The reaction mixture was stirred at room temperature. The solvent was evaporated under reduced pressure. The residue was quenched with saturated aqueous solution of ammonium chloride (20 ml) and extracted with methylene chloride (3 × 20 ml). The organic layer was dried over sodium sulfate (Na2SO4) and the solvent was removed under reduced pressure. Single crystals of the title compound were obtained by recrystallization from chloroform (CHCl3) solution, yield = 86% (white solid); m.p. = 174–176°C.
1H NMR (DMSO, δH p.p.m.): 2.94–3.02 (m, 3H, NH—CH—CH2– and –CH2-indol-3-yl); 3.28 (s, 3H, –OCH3); 3.64 (s, 3H, –OCH3); 3.67–3.72 (t, 1H, N—CH—CH2–, J = 6.90 Hz); 5.25–5.31 (dd, 1H, N—CH—N, J1 = 10.17 Hz and J2 = 7.73 Hz); 6.93–7.82 (m, 10H, 10Harom); 9.1 (s, 1H, NHBz); 10.9 (s, 1H, NHindole). 13C NMR (DMSO, δC p.p.m.): 29.18 (1 C, –CH2-indol-3-yl); 51.78 and 52.65 (2 C, –OCH3); 59.06 (1 C, –CH—CH2-indol-3-yl); 64.18 (1 C, N—CH—N); 109.80–136.48 (14 C, Carom); 166.61, 170.38 and 174.89 (3 C, CO). Calculated for C22H23N3O5 (%): C, 64.54; H, 5.66; N, 10.26; found (%): C 64.28, H 5.71, N 10.16. MS ESI m/z (%) = 409.60.
Refinement
Crystal data, data collection and structure . With no heavy atoms in the molecule the could not be determined reliably.
details are summarized in Table 2
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Structural data
CCDC reference: 1573006
https://doi.org/10.1107/S2414314617015474/sj4140sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617015474/sj4140Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314617015474/sj4140Isup3.cml
Data collection: APEX2 (Bruker, 2005); cell
SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2010).C22H23N3O5 | Dx = 1.337 Mg m−3 |
Mr = 409.43 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 275 reflections |
a = 9.5716 (3) Å | θ = 1.3–57° |
b = 11.6875 (4) Å | µ = 0.10 mm−1 |
c = 18.1827 (6) Å | T = 293 K |
V = 2034.06 (12) Å3 | Prism, colourless |
Z = 4 | 0.23 × 0.21 × 0.14 mm |
F(000) = 864 |
Bruker APEXII CCD diffractometer | 4675 independent reflections |
Radiation source: fine-focus sealed tube | 4359 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
φ and ω scan | θmax = 27.5°, θmin = 2.1° |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | h = −12→12 |
k = −15→15 | |
22029 measured reflections | l = −23→23 |
Refinement on F2 | Hydrogen site location: mixed |
Least-squares matrix: full | H atoms treated by a mixture of independent and constrained refinement |
R[F2 > 2σ(F2)] = 0.034 | w = 1/[σ2(Fo2) + (0.0569P)2 + 0.2737P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.097 | (Δ/σ)max < 0.001 |
S = 1.05 | Δρmax = 0.22 e Å−3 |
4675 reflections | Δρmin = −0.17 e Å−3 |
285 parameters | Absolute structure: Flack x determined using 1822 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013). |
3 restraints | Absolute structure parameter: 0.0 (2) |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
C7 | 0.71253 (18) | 0.07261 (14) | 0.23815 (10) | 0.0313 (3) | |
C6 | 0.77399 (19) | −0.04380 (14) | 0.22646 (10) | 0.0309 (3) | |
C5 | 0.7366 (2) | −0.11460 (15) | 0.16841 (10) | 0.0361 (4) | |
H5 | 0.6644 | −0.0934 | 0.1370 | 0.043* | |
C1 | 0.8802 (2) | −0.07750 (17) | 0.27415 (11) | 0.0393 (4) | |
H1 | 0.9056 | −0.0306 | 0.3133 | 0.047* | |
C4 | 0.8070 (2) | −0.21720 (17) | 0.15728 (13) | 0.0464 (5) | |
H4 | 0.7830 | −0.2640 | 0.1179 | 0.056* | |
C2 | 0.9483 (2) | −0.18102 (19) | 0.26330 (14) | 0.0486 (5) | |
H2 | 1.0180 | −0.2041 | 0.2957 | 0.058* | |
C3 | 0.9124 (2) | −0.24964 (19) | 0.20450 (14) | 0.0510 (5) | |
H3 | 0.9596 | −0.3181 | 0.1967 | 0.061* | |
N1 | 0.58969 (17) | 0.09702 (13) | 0.20564 (9) | 0.0349 (3) | |
C8 | 0.52998 (19) | 0.21167 (15) | 0.21117 (10) | 0.0327 (4) | |
H8 | 0.5171 | 0.2306 | 0.2632 | 0.039* | |
C9 | 0.6299 (2) | 0.29926 (15) | 0.17664 (11) | 0.0365 (4) | |
O1 | 0.77431 (17) | 0.14492 (12) | 0.27462 (9) | 0.0497 (4) | |
O3 | 0.61318 (19) | 0.40054 (12) | 0.20853 (9) | 0.0517 (4) | |
O2 | 0.70594 (19) | 0.28145 (14) | 0.12588 (10) | 0.0582 (4) | |
C10 | 0.6864 (3) | 0.4950 (2) | 0.17486 (19) | 0.0675 (7) | |
H10A | 0.6760 | 0.5621 | 0.2049 | 0.101* | |
H10B | 0.6480 | 0.5094 | 0.1270 | 0.101* | |
H10C | 0.7837 | 0.4764 | 0.1704 | 0.101* | |
N2 | 0.39521 (17) | 0.21076 (14) | 0.17551 (9) | 0.0352 (3) | |
C12 | 0.3859 (2) | 0.33133 (17) | 0.06305 (11) | 0.0401 (4) | |
C11 | 0.3936 (2) | 0.21081 (15) | 0.09530 (10) | 0.0340 (4) | |
H11 | 0.4796 | 0.1744 | 0.0777 | 0.041* | |
C13 | 0.3913 (3) | 0.4341 (2) | −0.04853 (15) | 0.0638 (7) | |
H13A | 0.4554 | 0.4918 | −0.0320 | 0.096* | |
H13B | 0.2972 | 0.4595 | −0.0403 | 0.096* | |
H13C | 0.4052 | 0.4205 | −0.1001 | 0.096* | |
O5 | 0.41550 (19) | 0.32938 (14) | −0.00816 (9) | 0.0514 (4) | |
O4 | 0.3559 (3) | 0.41515 (15) | 0.09638 (11) | 0.0743 (6) | |
N3 | 0.2625 (2) | −0.15885 (14) | 0.13318 (10) | 0.0431 (4) | |
C17 | 0.3845 (2) | −0.05961 (16) | 0.04926 (10) | 0.0370 (4) | |
C16 | 0.2847 (2) | 0.01589 (16) | 0.08328 (11) | 0.0379 (4) | |
C14 | 0.2676 (2) | 0.14084 (17) | 0.06700 (12) | 0.0413 (4) | |
H14A | 0.1828 | 0.1686 | 0.0902 | 0.050* | |
H14B | 0.2583 | 0.1516 | 0.0143 | 0.050* | |
C15 | 0.2145 (2) | −0.04813 (17) | 0.13370 (11) | 0.0422 (4) | |
H15 | 0.1441 | −0.0208 | 0.1642 | 0.051* | |
C22 | 0.3673 (2) | −0.16815 (16) | 0.08245 (11) | 0.0381 (4) | |
C18 | 0.4861 (2) | −0.0466 (2) | −0.00585 (12) | 0.0480 (5) | |
H18 | 0.4993 | 0.0237 | −0.0288 | 0.058* | |
C21 | 0.4464 (3) | −0.26306 (19) | 0.06147 (12) | 0.0481 (5) | |
H21 | 0.4324 | −0.3344 | 0.0829 | 0.058* | |
C19 | 0.5659 (3) | −0.1399 (2) | −0.02529 (14) | 0.0584 (6) | |
H19 | 0.6345 | −0.1318 | −0.0611 | 0.070* | |
C20 | 0.5456 (3) | −0.2470 (2) | 0.00800 (14) | 0.0564 (6) | |
H20 | 0.6007 | −0.3085 | −0.0065 | 0.068* | |
H2N | 0.343 (3) | 0.2689 (19) | 0.1905 (14) | 0.047 (7)* | |
H1N | 0.537 (2) | 0.0475 (18) | 0.1878 (12) | 0.036 (6)* | |
H3N | 0.233 (3) | −0.212 (2) | 0.1624 (15) | 0.070 (9)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C7 | 0.0333 (8) | 0.0256 (7) | 0.0350 (8) | −0.0013 (7) | 0.0002 (7) | −0.0008 (6) |
C6 | 0.0307 (8) | 0.0247 (7) | 0.0373 (8) | −0.0019 (6) | 0.0032 (7) | 0.0033 (6) |
C5 | 0.0382 (9) | 0.0278 (8) | 0.0422 (10) | −0.0006 (7) | 0.0000 (8) | 0.0005 (7) |
C1 | 0.0341 (8) | 0.0367 (9) | 0.0472 (10) | −0.0005 (8) | −0.0037 (8) | 0.0032 (8) |
C4 | 0.0507 (11) | 0.0310 (9) | 0.0574 (12) | −0.0001 (8) | 0.0075 (9) | −0.0088 (8) |
C2 | 0.0337 (9) | 0.0427 (11) | 0.0694 (14) | 0.0071 (8) | −0.0038 (9) | 0.0087 (10) |
C3 | 0.0427 (11) | 0.0310 (9) | 0.0793 (15) | 0.0081 (8) | 0.0102 (10) | −0.0008 (10) |
N1 | 0.0366 (8) | 0.0219 (6) | 0.0463 (8) | 0.0003 (6) | −0.0065 (7) | −0.0013 (6) |
C8 | 0.0366 (9) | 0.0256 (8) | 0.0358 (8) | 0.0032 (7) | −0.0010 (7) | 0.0002 (7) |
C9 | 0.0394 (9) | 0.0290 (8) | 0.0411 (9) | 0.0009 (7) | −0.0015 (8) | 0.0024 (7) |
O1 | 0.0485 (8) | 0.0338 (7) | 0.0669 (9) | 0.0035 (6) | −0.0163 (7) | −0.0159 (7) |
O3 | 0.0640 (10) | 0.0268 (7) | 0.0643 (9) | −0.0053 (7) | 0.0080 (8) | −0.0036 (6) |
O2 | 0.0665 (10) | 0.0450 (8) | 0.0630 (9) | −0.0052 (8) | 0.0244 (9) | −0.0024 (7) |
C10 | 0.0796 (18) | 0.0320 (11) | 0.0910 (19) | −0.0118 (11) | 0.0063 (16) | 0.0059 (12) |
N2 | 0.0335 (7) | 0.0330 (7) | 0.0391 (8) | 0.0057 (6) | 0.0023 (6) | 0.0022 (6) |
C12 | 0.0409 (10) | 0.0335 (9) | 0.0460 (10) | 0.0008 (8) | 0.0002 (8) | 0.0089 (8) |
C11 | 0.0343 (8) | 0.0279 (8) | 0.0396 (9) | 0.0044 (7) | −0.0009 (7) | 0.0047 (7) |
C13 | 0.0725 (16) | 0.0576 (15) | 0.0614 (14) | −0.0001 (13) | −0.0020 (13) | 0.0283 (12) |
O5 | 0.0655 (10) | 0.0446 (8) | 0.0442 (8) | 0.0014 (7) | −0.0002 (7) | 0.0135 (6) |
O4 | 0.1215 (18) | 0.0361 (8) | 0.0655 (11) | 0.0202 (10) | 0.0198 (11) | 0.0083 (8) |
N3 | 0.0521 (10) | 0.0345 (8) | 0.0429 (9) | −0.0053 (7) | 0.0003 (8) | 0.0085 (7) |
C17 | 0.0414 (10) | 0.0336 (9) | 0.0360 (9) | −0.0049 (8) | −0.0063 (8) | 0.0004 (7) |
C16 | 0.0416 (10) | 0.0335 (9) | 0.0386 (9) | −0.0027 (8) | −0.0074 (8) | 0.0023 (7) |
C14 | 0.0405 (10) | 0.0345 (9) | 0.0488 (11) | −0.0003 (8) | −0.0099 (9) | 0.0080 (8) |
C15 | 0.0457 (10) | 0.0388 (9) | 0.0421 (10) | −0.0012 (9) | 0.0009 (9) | 0.0026 (8) |
C22 | 0.0417 (10) | 0.0340 (9) | 0.0386 (9) | −0.0050 (8) | −0.0091 (8) | −0.0005 (8) |
C18 | 0.0519 (12) | 0.0469 (12) | 0.0451 (11) | −0.0085 (10) | 0.0022 (9) | 0.0012 (9) |
C21 | 0.0572 (12) | 0.0339 (10) | 0.0534 (12) | −0.0001 (9) | −0.0111 (10) | −0.0056 (9) |
C19 | 0.0559 (14) | 0.0651 (15) | 0.0543 (13) | −0.0040 (12) | 0.0085 (11) | −0.0120 (11) |
C20 | 0.0565 (13) | 0.0512 (12) | 0.0614 (13) | 0.0065 (11) | −0.0012 (11) | −0.0177 (11) |
C7—O1 | 1.226 (2) | C12—O5 | 1.326 (3) |
C7—N1 | 1.347 (2) | C12—C11 | 1.528 (2) |
C7—C6 | 1.497 (2) | C11—C14 | 1.546 (3) |
C6—C5 | 1.388 (3) | C11—H11 | 0.9800 |
C6—C1 | 1.393 (3) | C13—O5 | 1.446 (3) |
C5—C4 | 1.391 (3) | C13—H13A | 0.9600 |
C5—H5 | 0.9300 | C13—H13B | 0.9600 |
C1—C2 | 1.388 (3) | C13—H13C | 0.9600 |
C1—H1 | 0.9300 | N3—C22 | 1.367 (3) |
C4—C3 | 1.378 (3) | N3—C15 | 1.373 (3) |
C4—H4 | 0.9300 | N3—H3N | 0.87 (2) |
C2—C3 | 1.380 (3) | C17—C18 | 1.405 (3) |
C2—H2 | 0.9300 | C17—C22 | 1.414 (3) |
C3—H3 | 0.9300 | C17—C16 | 1.440 (3) |
N1—C8 | 1.460 (2) | C16—C15 | 1.361 (3) |
N1—H1N | 0.831 (19) | C16—C14 | 1.499 (3) |
C8—N2 | 1.444 (2) | C14—H14A | 0.9700 |
C8—C9 | 1.535 (3) | C14—H14B | 0.9700 |
C8—H8 | 0.9800 | C15—H15 | 0.9300 |
C9—O2 | 1.194 (3) | C22—C21 | 1.396 (3) |
C9—O3 | 1.328 (2) | C18—C19 | 1.377 (4) |
O3—C10 | 1.444 (3) | C18—H18 | 0.9300 |
C10—H10A | 0.9600 | C21—C20 | 1.372 (4) |
C10—H10B | 0.9600 | C21—H21 | 0.9300 |
C10—H10C | 0.9600 | C19—C20 | 1.404 (4) |
N2—C11 | 1.459 (2) | C19—H19 | 0.9300 |
N2—H2N | 0.89 (2) | C20—H20 | 0.9300 |
C12—O4 | 1.187 (3) | ||
O1—C7—N1 | 120.83 (16) | N2—C11—C12 | 112.63 (16) |
O1—C7—C6 | 120.90 (16) | N2—C11—C14 | 109.92 (16) |
N1—C7—C6 | 118.24 (15) | C12—C11—C14 | 108.79 (15) |
C5—C6—C1 | 119.54 (17) | N2—C11—H11 | 108.5 |
C5—C6—C7 | 123.24 (16) | C12—C11—H11 | 108.5 |
C1—C6—C7 | 117.08 (16) | C14—C11—H11 | 108.5 |
C6—C5—C4 | 119.97 (18) | O5—C13—H13A | 109.5 |
C6—C5—H5 | 120.0 | O5—C13—H13B | 109.5 |
C4—C5—H5 | 120.0 | H13A—C13—H13B | 109.5 |
C2—C1—C6 | 120.0 (2) | O5—C13—H13C | 109.5 |
C2—C1—H1 | 120.0 | H13A—C13—H13C | 109.5 |
C6—C1—H1 | 120.0 | H13B—C13—H13C | 109.5 |
C3—C4—C5 | 120.1 (2) | C12—O5—C13 | 116.56 (19) |
C3—C4—H4 | 119.9 | C22—N3—C15 | 108.96 (16) |
C5—C4—H4 | 119.9 | C22—N3—H3N | 127 (2) |
C3—C2—C1 | 120.0 (2) | C15—N3—H3N | 124 (2) |
C3—C2—H2 | 120.0 | C18—C17—C22 | 118.80 (19) |
C1—C2—H2 | 120.0 | C18—C17—C16 | 134.39 (19) |
C4—C3—C2 | 120.33 (19) | C22—C17—C16 | 106.81 (18) |
C4—C3—H3 | 119.8 | C15—C16—C17 | 106.25 (17) |
C2—C3—H3 | 119.8 | C15—C16—C14 | 127.9 (2) |
C7—N1—C8 | 120.39 (15) | C17—C16—C14 | 125.78 (19) |
C7—N1—H1N | 123.4 (16) | C16—C14—C11 | 111.37 (16) |
C8—N1—H1N | 115.5 (16) | C16—C14—H14A | 109.4 |
N2—C8—N1 | 108.18 (15) | C11—C14—H14A | 109.4 |
N2—C8—C9 | 112.20 (15) | C16—C14—H14B | 109.4 |
N1—C8—C9 | 109.88 (15) | C11—C14—H14B | 109.4 |
N2—C8—H8 | 108.8 | H14A—C14—H14B | 108.0 |
N1—C8—H8 | 108.8 | C16—C15—N3 | 110.40 (19) |
C9—C8—H8 | 108.8 | C16—C15—H15 | 124.8 |
O2—C9—O3 | 124.51 (19) | N3—C15—H15 | 124.8 |
O2—C9—C8 | 125.43 (18) | N3—C22—C21 | 130.20 (19) |
O3—C9—C8 | 109.93 (16) | N3—C22—C17 | 107.58 (17) |
C9—O3—C10 | 115.99 (19) | C21—C22—C17 | 122.2 (2) |
O3—C10—H10A | 109.5 | C19—C18—C17 | 118.8 (2) |
O3—C10—H10B | 109.5 | C19—C18—H18 | 120.6 |
H10A—C10—H10B | 109.5 | C17—C18—H18 | 120.6 |
O3—C10—H10C | 109.5 | C20—C21—C22 | 117.4 (2) |
H10A—C10—H10C | 109.5 | C20—C21—H21 | 121.3 |
H10B—C10—H10C | 109.5 | C22—C21—H21 | 121.3 |
C8—N2—C11 | 117.27 (15) | C18—C19—C20 | 121.2 (2) |
C8—N2—H2N | 111.2 (17) | C18—C19—H19 | 119.4 |
C11—N2—H2N | 107.5 (16) | C20—C19—H19 | 119.4 |
O4—C12—O5 | 124.37 (19) | C21—C20—C19 | 121.6 (2) |
O4—C12—C11 | 125.23 (19) | C21—C20—H20 | 119.2 |
O5—C12—C11 | 110.40 (17) | C19—C20—H20 | 119.2 |
Cg1, Cg2 and Cg3 are the centroids of the N3/C15–C17/C22, C1–C6 and C17–C22 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3N···O1i | 0.87 (2) | 2.03 (2) | 2.862 (2) | 162 (3) |
N2—H2N···Cg2ii | 0.89 (2) | 2.65 (3) | 3.4451 (18) | 149 (2) |
C5—H5···Cg3 | 0.93 | 2.83 | 3.662 (2) | 149 |
C20—H20···Cg1iii | 0.93 | 2.83 | 3.684 (3) | 154 |
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x+1, y+1/2, −z+1/2; (iii) x+1/2, −y−1/2, −z. |
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