organic compounds
Diethyl 4-(1H-indol-3-yl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate
aDepartment of Applied Chemistry, Dongduk Women's University, Seoul 136-714, Republic of Korea
*Correspondence e-mail: dskoh@dongduk.ac.kr
In the title compound, C21H24N2O4, the 1,4-dihydropyridine ring adopts a very flattened boat conformation, with the 3-pyridine substituent in an axial orientation. The pyridine ring is almost orthogonally twisted relative to the 1,4-dihydropyridine skeleton by 85.97 (2)°. In the crystal, pairs of N—H⋯O hydrogen bonds form inversion dimers enclosing R22(16) rings. Pairs of intermolecular N—H⋯O hydrogen bonds link the dimers into chains along [100].
CCDC reference: 1895315
Structure description
1,4-dihydropyridine (1,4-DHP) derivatives are known as Hantzsch compounds. According to our recent report, they show anti-cancer activities against the HCT116 human colon cancer cell lines (Ahn et al., 2018). Their biological activities include anticonvulsant (Prasanthi et al., 2014), calcium channel modulator (Budriesi et al., 2005), anti-tubercular (Khoshneviszadeh et al., 2009) and antimycobacterial activities (Lentz et al., 2016).
The molecular structure of the title compound is shown in Fig. 1. The 1,4-dihydropyridine (C1–C5/N1) ring is slightly twisted from planarity, with a maximum deviation of 0.138 (1) Å at C3 (r.m.s. deviation = 0.091 Å). The dihedral angle formed between the plane of the 1,4-dihydropyridine (C1–C5/N1) ring and the indole (C10–C17/N2; r.m.s. deviation = 0.011 Å) ring is 85.97 (2)°. One of the carbonyl groups (C7=O1) lies on the same side of the plane as the methyl group at C6, while the other carbonyl group (C18=O3) lies on the opposite side to the methyl group at C21.
In the ii hydrogen bonds form inversion dimers enclosing R22(16) rings (Table 1, Fig. 2). The dimers are linked into chains along the a-axis direction by pairs of N1—H1⋯O1i hydrogen bonds (Table 1, Fig. 3).
pairs of N2—H2⋯O3Synthesis and crystallization
Methyl acetoacetate (20 mmol) and indole-3-carbaldehyde (10 mmol) were dissolved in 30 ml of ethanol to give a clear solution. To the mixture, ammonium acetate (10 mmol) was added and the reaction mixture was heated at 363 K for 2 h. After completion of the reaction (monitored by TLC), the mixture was cooled to room temperature to produce a solid product. This solid was recrystallized from ethanol solution to obtain single-crystal of the title the compound in 51% yield.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1895315
https://doi.org/10.1107/S2414314619001937/zq4034sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314619001937/zq4034Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314619001937/zq4034Isup3.cml
Data collection: APEX2 (Bruker, 2012); cell
SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).C21H24N2O4 | F(000) = 784 |
Mr = 368.42 | Dx = 1.245 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 10.6258 (5) Å | Cell parameters from 9897 reflections |
b = 10.2217 (5) Å | θ = 2.3–25.4° |
c = 18.0993 (8) Å | µ = 0.09 mm−1 |
β = 90.798 (2)° | T = 223 K |
V = 1965.64 (16) Å3 | Block, colourless |
Z = 4 | 0.24 × 0.18 × 0.14 mm |
PHOTON 100 CMOS diffractometer | 3123 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.096 |
Absorption correction: multi-scan (SADABS; Bruker, 2012) | θmax = 28.3°, θmin = 1.9° |
Tmin = 0.686, Tmax = 0.746 | h = −14→14 |
83213 measured reflections | k = −13→13 |
4908 independent reflections | l = −24→24 |
Refinement on F2 | 4 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.063 | H-atom parameters not refined |
wR(F2) = 0.198 | w = 1/[σ2(Fo2) + (0.087P)2 + 1.2621P] where P = (Fo2 + 2Fc2)/3 |
S = 1.02 | (Δ/σ)max < 0.001 |
4908 reflections | Δρmax = 0.54 e Å−3 |
254 parameters | Δρmin = −0.47 e Å−3 |
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 | ||
N1 | 0.00309 (17) | 0.61066 (19) | 0.15703 (10) | 0.0407 (4) | |
H1 | −0.0613 (19) | 0.648 (2) | 0.1808 (13) | 0.049* | |
C1 | 0.04291 (19) | 0.4898 (2) | 0.18142 (12) | 0.0381 (5) | |
C2 | 0.13159 (19) | 0.4253 (2) | 0.14337 (11) | 0.0358 (5) | |
C3 | 0.19820 (19) | 0.4892 (2) | 0.07873 (11) | 0.0367 (5) | |
H3 | 0.2050 | 0.4229 | 0.0391 | 0.044* | |
C4 | 0.12181 (19) | 0.6032 (2) | 0.04792 (11) | 0.0375 (5) | |
C5 | 0.0307 (2) | 0.6611 (2) | 0.08802 (12) | 0.0394 (5) | |
C6 | −0.0235 (3) | 0.4445 (3) | 0.24927 (14) | 0.0536 (6) | |
H6A | −0.0521 | 0.3552 | 0.2422 | 0.080* | |
H6B | −0.0952 | 0.5007 | 0.2582 | 0.080* | |
H6C | 0.0339 | 0.4482 | 0.2914 | 0.080* | |
C7 | 0.1697 (2) | 0.2926 (2) | 0.16465 (12) | 0.0401 (5) | |
O1 | 0.14621 (16) | 0.23585 (17) | 0.22188 (10) | 0.0525 (5) | |
O2 | 0.23841 (17) | 0.23580 (16) | 0.11138 (9) | 0.0528 (5) | |
C8 | 0.2857 (3) | 0.1066 (3) | 0.12725 (17) | 0.0689 (8) | |
H8A | 0.2160 | 0.0440 | 0.1291 | 0.083* | |
H8B | 0.3297 | 0.1059 | 0.1752 | 0.083* | |
C9 | 0.3752 (5) | 0.0696 (5) | 0.0667 (2) | 0.131 (2) | |
H9A | 0.3319 | 0.0747 | 0.0192 | 0.196* | |
H9B | 0.4051 | −0.0190 | 0.0747 | 0.196* | |
H9C | 0.4462 | 0.1293 | 0.0672 | 0.196* | |
C10 | 0.33057 (19) | 0.5307 (2) | 0.10047 (11) | 0.0366 (5) | |
C11 | 0.4375 (2) | 0.4691 (3) | 0.07841 (13) | 0.0443 (5) | |
H11 | 0.4394 | 0.3950 | 0.0476 | 0.053* | |
N2 | 0.54168 (18) | 0.5301 (2) | 0.10733 (11) | 0.0497 (5) | |
H2 | 0.6204 (18) | 0.505 (3) | 0.0940 (15) | 0.060* | |
C12 | 0.5038 (2) | 0.6340 (3) | 0.14898 (12) | 0.0434 (5) | |
C13 | 0.5751 (2) | 0.7250 (3) | 0.18868 (14) | 0.0569 (7) | |
H13 | 0.6635 | 0.7225 | 0.1884 | 0.068* | |
C14 | 0.5125 (3) | 0.8182 (3) | 0.22819 (16) | 0.0611 (7) | |
H14 | 0.5588 | 0.8798 | 0.2559 | 0.073* | |
C15 | 0.3812 (3) | 0.8233 (3) | 0.22806 (15) | 0.0554 (6) | |
H15 | 0.3404 | 0.8879 | 0.2558 | 0.067* | |
C16 | 0.3107 (2) | 0.7345 (2) | 0.18760 (13) | 0.0455 (5) | |
H16 | 0.2223 | 0.7396 | 0.1874 | 0.055* | |
C17 | 0.37063 (19) | 0.6372 (2) | 0.14690 (12) | 0.0379 (5) | |
C18 | 0.1572 (2) | 0.6424 (2) | −0.02674 (13) | 0.0434 (5) | |
O3 | 0.21205 (15) | 0.57075 (19) | −0.06892 (9) | 0.0527 (5) | |
O4 | 0.1257 (2) | 0.76502 (19) | −0.04444 (10) | 0.0688 (6) | |
C19 | 0.1540 (3) | 0.8084 (4) | −0.11777 (17) | 0.0840 (10) | |
H19A | 0.0812 | 0.8548 | −0.1390 | 0.101* | |
H19B | 0.1719 | 0.7328 | −0.1492 | 0.101* | |
C20 | 0.2678 (5) | 0.8993 (6) | −0.1152 (3) | 0.144 (2) | |
H20A | 0.2520 | 0.9706 | −0.0812 | 0.215* | |
H20B | 0.2823 | 0.9343 | −0.1642 | 0.215* | |
H20C | 0.3413 | 0.8508 | −0.0986 | 0.215* | |
C21 | −0.0505 (3) | 0.7756 (3) | 0.06674 (15) | 0.0557 (7) | |
H21A | −0.0035 | 0.8561 | 0.0740 | 0.084* | |
H21B | −0.1248 | 0.7768 | 0.0973 | 0.084* | |
H21C | −0.0756 | 0.7680 | 0.0152 | 0.084* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0359 (9) | 0.0443 (11) | 0.0421 (10) | 0.0035 (8) | 0.0093 (8) | −0.0045 (8) |
C1 | 0.0335 (10) | 0.0409 (12) | 0.0400 (11) | −0.0048 (9) | 0.0042 (9) | −0.0035 (9) |
C2 | 0.0310 (10) | 0.0386 (11) | 0.0380 (11) | −0.0024 (8) | 0.0031 (8) | −0.0007 (9) |
C3 | 0.0333 (10) | 0.0409 (12) | 0.0361 (11) | 0.0004 (9) | 0.0038 (8) | −0.0014 (9) |
C4 | 0.0308 (10) | 0.0453 (12) | 0.0362 (11) | −0.0004 (9) | −0.0004 (8) | −0.0025 (9) |
C5 | 0.0349 (11) | 0.0415 (12) | 0.0417 (11) | 0.0006 (9) | −0.0035 (9) | −0.0031 (9) |
C6 | 0.0570 (15) | 0.0502 (14) | 0.0542 (14) | −0.0020 (12) | 0.0224 (12) | −0.0021 (12) |
C7 | 0.0323 (10) | 0.0420 (12) | 0.0461 (12) | −0.0039 (9) | 0.0041 (9) | −0.0024 (10) |
O1 | 0.0498 (10) | 0.0510 (10) | 0.0570 (10) | 0.0044 (8) | 0.0163 (8) | 0.0125 (8) |
O2 | 0.0616 (11) | 0.0435 (9) | 0.0536 (10) | 0.0114 (8) | 0.0154 (8) | 0.0003 (8) |
C8 | 0.079 (2) | 0.0482 (16) | 0.080 (2) | 0.0195 (14) | 0.0211 (16) | 0.0032 (14) |
C9 | 0.166 (5) | 0.105 (3) | 0.123 (3) | 0.075 (3) | 0.057 (3) | 0.013 (3) |
C10 | 0.0309 (10) | 0.0454 (12) | 0.0335 (10) | 0.0019 (9) | 0.0050 (8) | 0.0062 (9) |
C11 | 0.0351 (11) | 0.0564 (14) | 0.0414 (12) | 0.0046 (10) | 0.0052 (9) | 0.0003 (11) |
N2 | 0.0293 (9) | 0.0713 (14) | 0.0486 (11) | 0.0064 (9) | 0.0059 (8) | −0.0001 (10) |
C12 | 0.0322 (11) | 0.0590 (14) | 0.0392 (11) | 0.0001 (10) | 0.0037 (9) | 0.0073 (10) |
C13 | 0.0368 (12) | 0.0796 (19) | 0.0540 (14) | −0.0115 (13) | −0.0055 (11) | 0.0054 (14) |
C14 | 0.0548 (16) | 0.0669 (18) | 0.0614 (16) | −0.0131 (14) | −0.0099 (13) | −0.0080 (14) |
C15 | 0.0530 (15) | 0.0546 (15) | 0.0586 (15) | −0.0028 (12) | −0.0026 (12) | −0.0103 (12) |
C16 | 0.0387 (12) | 0.0481 (13) | 0.0498 (13) | 0.0004 (10) | 0.0002 (10) | −0.0027 (11) |
C17 | 0.0318 (10) | 0.0455 (12) | 0.0365 (10) | −0.0004 (9) | 0.0016 (8) | 0.0070 (9) |
C18 | 0.0360 (11) | 0.0508 (14) | 0.0432 (12) | −0.0003 (10) | −0.0059 (9) | 0.0014 (11) |
O3 | 0.0418 (9) | 0.0740 (12) | 0.0424 (9) | 0.0091 (8) | 0.0071 (7) | 0.0025 (8) |
O4 | 0.1006 (16) | 0.0565 (12) | 0.0496 (11) | 0.0063 (11) | 0.0064 (10) | 0.0113 (9) |
C19 | 0.123 (3) | 0.077 (2) | 0.0526 (17) | −0.005 (2) | −0.0008 (18) | 0.0205 (16) |
C20 | 0.187 (5) | 0.153 (5) | 0.092 (3) | −0.089 (4) | 0.022 (3) | 0.004 (3) |
C21 | 0.0513 (14) | 0.0575 (16) | 0.0581 (15) | 0.0149 (12) | −0.0031 (12) | −0.0005 (13) |
N1—C1 | 1.376 (3) | C11—N2 | 1.368 (3) |
N1—C5 | 1.387 (3) | C11—H11 | 0.9400 |
N1—H1 | 0.899 (16) | N2—C12 | 1.366 (3) |
C1—C2 | 1.348 (3) | N2—H2 | 0.911 (17) |
C1—C6 | 1.498 (3) | C12—C13 | 1.393 (4) |
C2—C7 | 1.465 (3) | C12—C17 | 1.416 (3) |
C2—C3 | 1.523 (3) | C13—C14 | 1.369 (4) |
C3—C10 | 1.516 (3) | C13—H13 | 0.9400 |
C3—C4 | 1.521 (3) | C14—C15 | 1.396 (4) |
C3—H3 | 0.9900 | C14—H14 | 0.9400 |
C4—C5 | 1.354 (3) | C15—C16 | 1.381 (3) |
C4—C18 | 1.463 (3) | C15—H15 | 0.9400 |
C5—C21 | 1.501 (3) | C16—C17 | 1.397 (3) |
C6—H6A | 0.9700 | C16—H16 | 0.9400 |
C6—H6B | 0.9700 | C18—O3 | 1.213 (3) |
C6—H6C | 0.9700 | C18—O4 | 1.335 (3) |
C7—O1 | 1.216 (3) | O4—C19 | 1.435 (3) |
C7—O2 | 1.349 (3) | C19—C20 | 1.5250 (19) |
O2—C8 | 1.440 (3) | C19—H19A | 0.9800 |
C8—C9 | 1.509 (3) | C19—H19B | 0.9800 |
C8—H8A | 0.9800 | C20—H20A | 0.9700 |
C8—H8B | 0.9800 | C20—H20B | 0.9700 |
C9—H9A | 0.9700 | C20—H20C | 0.9700 |
C9—H9B | 0.9700 | C21—H21A | 0.9700 |
C9—H9C | 0.9700 | C21—H21B | 0.9700 |
C10—C11 | 1.364 (3) | C21—H21C | 0.9700 |
C10—C17 | 1.436 (3) | ||
C1—N1—C5 | 123.70 (18) | C10—C11—N2 | 110.5 (2) |
C1—N1—H1 | 117.4 (16) | C10—C11—H11 | 124.7 |
C5—N1—H1 | 116.5 (16) | N2—C11—H11 | 124.7 |
C2—C1—N1 | 119.32 (19) | C12—N2—C11 | 108.83 (19) |
C2—C1—C6 | 127.5 (2) | C12—N2—H2 | 130.1 (18) |
N1—C1—C6 | 113.22 (19) | C11—N2—H2 | 120.7 (18) |
C1—C2—C7 | 120.77 (19) | N2—C12—C13 | 129.9 (2) |
C1—C2—C3 | 121.2 (2) | N2—C12—C17 | 107.8 (2) |
C7—C2—C3 | 117.99 (18) | C13—C12—C17 | 122.3 (2) |
C10—C3—C4 | 111.69 (18) | C14—C13—C12 | 118.0 (2) |
C10—C3—C2 | 111.10 (17) | C14—C13—H13 | 121.0 |
C4—C3—C2 | 111.04 (17) | C12—C13—H13 | 121.0 |
C10—C3—H3 | 107.6 | C13—C14—C15 | 121.2 (3) |
C4—C3—H3 | 107.6 | C13—C14—H14 | 119.4 |
C2—C3—H3 | 107.6 | C15—C14—H14 | 119.4 |
C5—C4—C18 | 124.7 (2) | C16—C15—C14 | 120.8 (3) |
C5—C4—C3 | 121.34 (19) | C16—C15—H15 | 119.6 |
C18—C4—C3 | 113.93 (18) | C14—C15—H15 | 119.6 |
C4—C5—N1 | 118.8 (2) | C15—C16—C17 | 120.0 (2) |
C4—C5—C21 | 128.0 (2) | C15—C16—H16 | 120.0 |
N1—C5—C21 | 113.2 (2) | C17—C16—H16 | 120.0 |
C1—C6—H6A | 109.5 | C16—C17—C12 | 117.7 (2) |
C1—C6—H6B | 109.5 | C16—C17—C10 | 135.6 (2) |
H6A—C6—H6B | 109.5 | C12—C17—C10 | 106.63 (19) |
C1—C6—H6C | 109.5 | O3—C18—O4 | 122.4 (2) |
H6A—C6—H6C | 109.5 | O3—C18—C4 | 123.2 (2) |
H6B—C6—H6C | 109.5 | O4—C18—C4 | 114.3 (2) |
O1—C7—O2 | 121.5 (2) | C18—O4—C19 | 117.2 (2) |
O1—C7—C2 | 127.3 (2) | O4—C19—C20 | 109.6 (3) |
O2—C7—C2 | 111.17 (19) | O4—C19—H19A | 109.7 |
C7—O2—C8 | 116.30 (19) | C20—C19—H19A | 109.7 |
O2—C8—C9 | 107.9 (3) | O4—C19—H19B | 109.7 |
O2—C8—H8A | 110.1 | C20—C19—H19B | 109.7 |
C9—C8—H8A | 110.1 | H19A—C19—H19B | 108.2 |
O2—C8—H8B | 110.1 | C19—C20—H20A | 109.5 |
C9—C8—H8B | 110.1 | C19—C20—H20B | 109.5 |
H8A—C8—H8B | 108.4 | H20A—C20—H20B | 109.5 |
C8—C9—H9A | 109.5 | C19—C20—H20C | 109.5 |
C8—C9—H9B | 109.5 | H20A—C20—H20C | 109.5 |
H9A—C9—H9B | 109.5 | H20B—C20—H20C | 109.5 |
C8—C9—H9C | 109.5 | C5—C21—H21A | 109.5 |
H9A—C9—H9C | 109.5 | C5—C21—H21B | 109.5 |
H9B—C9—H9C | 109.5 | H21A—C21—H21B | 109.5 |
C11—C10—C17 | 106.24 (19) | C5—C21—H21C | 109.5 |
C11—C10—C3 | 124.7 (2) | H21A—C21—H21C | 109.5 |
C17—C10—C3 | 129.07 (19) | H21B—C21—H21C | 109.5 |
C5—N1—C1—C2 | 12.5 (3) | C4—C3—C10—C17 | 51.8 (3) |
C5—N1—C1—C6 | −166.3 (2) | C2—C3—C10—C17 | −72.8 (3) |
N1—C1—C2—C7 | −175.62 (19) | C17—C10—C11—N2 | −0.4 (3) |
C6—C1—C2—C7 | 3.0 (4) | C3—C10—C11—N2 | 180.0 (2) |
N1—C1—C2—C3 | 6.4 (3) | C10—C11—N2—C12 | −0.2 (3) |
C6—C1—C2—C3 | −175.0 (2) | C11—N2—C12—C13 | −179.6 (2) |
C1—C2—C3—C10 | 104.3 (2) | C11—N2—C12—C17 | 0.8 (3) |
C7—C2—C3—C10 | −73.7 (2) | N2—C12—C13—C14 | −177.9 (3) |
C1—C2—C3—C4 | −20.7 (3) | C17—C12—C13—C14 | 1.6 (4) |
C7—C2—C3—C4 | 161.33 (18) | C12—C13—C14—C15 | −0.8 (4) |
C10—C3—C4—C5 | −105.6 (2) | C13—C14—C15—C16 | −0.3 (4) |
C2—C3—C4—C5 | 19.0 (3) | C14—C15—C16—C17 | 0.8 (4) |
C10—C3—C4—C18 | 73.9 (2) | C15—C16—C17—C12 | −0.1 (3) |
C2—C3—C4—C18 | −161.51 (18) | C15—C16—C17—C10 | 179.2 (2) |
C18—C4—C5—N1 | 177.33 (19) | N2—C12—C17—C16 | 178.5 (2) |
C3—C4—C5—N1 | −3.2 (3) | C13—C12—C17—C16 | −1.1 (3) |
C18—C4—C5—C21 | −1.1 (4) | N2—C12—C17—C10 | −1.1 (2) |
C3—C4—C5—C21 | 178.4 (2) | C13—C12—C17—C10 | 179.3 (2) |
C1—N1—C5—C4 | −14.2 (3) | C11—C10—C17—C16 | −178.5 (3) |
C1—N1—C5—C21 | 164.4 (2) | C3—C10—C17—C16 | 1.1 (4) |
C1—C2—C7—O1 | −13.3 (4) | C11—C10—C17—C12 | 0.9 (2) |
C3—C2—C7—O1 | 164.7 (2) | C3—C10—C17—C12 | −179.5 (2) |
C1—C2—C7—O2 | 167.0 (2) | C5—C4—C18—O3 | −159.2 (2) |
C3—C2—C7—O2 | −15.0 (3) | C3—C4—C18—O3 | 21.3 (3) |
O1—C7—O2—C8 | −2.1 (3) | C5—C4—C18—O4 | 21.9 (3) |
C2—C7—O2—C8 | 177.6 (2) | C3—C4—C18—O4 | −157.6 (2) |
C7—O2—C8—C9 | −171.5 (3) | O3—C18—O4—C19 | 3.1 (4) |
C4—C3—C10—C11 | −128.8 (2) | C4—C18—O4—C19 | −178.0 (2) |
C2—C3—C10—C11 | 106.7 (2) | C18—O4—C19—C20 | −104.9 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1i | 0.90 (2) | 2.18 (2) | 3.009 (2) | 153 (2) |
N2—H2···O3ii | 0.91 (2) | 2.00 (2) | 2.906 (3) | 173 (3) |
C6—H6B···O1i | 0.97 | 2.49 | 3.296 (3) | 140 |
C13—H13···O1iii | 0.94 | 2.58 | 3.357 (3) | 140 |
Symmetry codes: (i) −x, y+1/2, −z+1/2; (ii) −x+1, −y+1, −z; (iii) −x+1, y+1/2, −z+1/2. |
Funding information
The authors acknowledge financial support from the Basic Science Research Program (award No. NRF– 2016R1D1A1B03931623).
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