Crystal structure of diethyl 3,3′-[(2,4-di­chloro­phen­yl)methyl­idene]bis­(1H-indole-2-carboxyl­ate)

Li, Y.-L.; Sun, H.-S.; Jiang, H.; Chen, Y.-L.; Chen, Y.-F.

doi:10.1107/S2056989017015730

research communications

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ISSN: 2056-9890

Volume 73| Part 12| December 2017| Pages 1817-1819

https://doi.org/10.1107/S2056989017015730

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Crystal structure of diethyl 3,3′-[(2,4-dichlorophenyl)methylidene]bis(1H-indole-2-carboxylate)

Yu-Long Li,^a Hong-Shun Sun,^a ^* Hong Jiang,^a Yu-Liang Chen ^a and Yang-Feng Chen ^a

^aTargeted MRI Contrast Agents Laboratory of Jiangsu Province, Nanjing Polytechnic Institute, Geguan Road No. 265 Nanjing, Nanjing 210048, People's Republic of China
^*Correspondence e-mail: njutshs@126.com

Edited by J. Simpson, University of Otago, New Zealand (Received 16 October 2017; accepted 29 October 2017; online 3 November 2017)

In the title compound, C₂₉H₂₄Cl₂N₂O₄, the mean planes of the two indole ring systems (r.m.s. deviations = 0.1249 and 0.0075 Å) are approximately perpendicular to one another, with a dihedral angle of 80.9 (5)° between them. The benzene ring is inclined to the mean planes of the two indole ring systems by 76.1 (3) and 78.3 (4)°. Weak intramolecular C—H⋯π interactions affect the molecular conformation. In the crystal, pairs of N—H⋯O hydrogen bonds link the molecules into inversion dimers which are further linked into supramolecular chains by N—H⋯O hydrogen bonds and short Cl—Cl contacts.

Keywords: crystal structure; bisindole; MRI; contrast agent.

CCDC reference: 1582719

1. Chemical context

Bis(indolyl)methane derivatives are abundantly present in various terrestrial and marine natural resources (Porter et al.,1977 ; Sundberg, 1996 ). They are important antibiotics in the field of pharmaceuticals with diverse activities, displaying anticancer, antileishmanial and antihyperlipidemic properties (Chang et al., 1999 ; Ge et al., 1999 ). Furthermore, bis(indolyl)methane derivatives can also be used as precursors for MRI necrosis avid contrast agents (Ni, 2008 ). In recent years, we have reported the synthesis and crystal structures of some similar bis(indoly)methane compounds (Sun et al., 2012 , 2015 ; Li et al., 2014 ; Lu et al., 2014 ). We report here the molecular and crystal structure of the title bis(indoly)methane derivative.

2. Structural commentary

The molecular structure of the title compound is shown in Fig. 1. The overall conformation of the molecule is affected by intramolecular C4—H4A⋯Cg5 and C15—H15A⋯Cg1 interactions (Cg1 and Cg5 are the centroids of the N1,C8,C3,C2,C9 and C24–C29 rings, respectively), Fig. 1, Table 1. The two indole ring systems are nearly perpendicular to one another, subtending a dihedral angle of 80.9 (5)° while the C24–C29 benzene ring is inclined to the N1/C2–C9 and N2/C13–C20 indole ring systems by dihedral angles of 76.1 (3) and 78.3 (4)°, respectively. The carboxyl groups lie close to the planes of the indole ring systems to which they are bound, with dihedral angles between the carboxyl groups and the mean planes of the N1/C2–C9 and N2/C13–C20 indole ring systems of 8.3 (5) and 5.6 (3)°, respectively.

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg5 are the centroids of the N1,C8,C3,C2,C9 and C24–C29 rings respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O1ⁱ	0.86	2.07	2.864 (4)	152
N2—H2A⋯O4ⁱⁱ	0.86	2.04	2.871 (4)	161
C11—H11A⋯Cl1ⁱⁱⁱ	0.97	2.81	3.731 (5)	158
C4—H4A⋯Cg5	0.93	2.77	3.516 (4)	137
C15—H15A⋯Cg1	0.93	2.72	3.476 (5)	139
Symmetry codes: (i) -x, -y+1, -z; (ii) -x+1, -y+2, -z; (iii) $[x-1, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ .

Figure 1
The molecular structure of the title molecule showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. Intramolecular C—H⋯π(ring) contacts (Table 1

) are shown as dotted black lines with ring centroids displayed as coloured spheres.

3. Supramolecular features

In the crystal, pairs of N1—H1A⋯O1 and N2—H2A⋯O4 hydrogen bonds, Table 1, link the molecules into inversion dimers that form supramolecular chains along the b-axis direction. C11—H11A⋯Cl1 and short Cl2⋯Cl2 contacts [Cl2⋯Cl2(1 − x, 1 − y, −z) = 3.467 (2) Å] bridge these chains and form sheets of molecules parallel to ( $[\overline{1}]$ 12), Fig. 2.

Figure 2
A packing diagram of the title compound. Hydrogen bonds (Table 1

) and Cl⋯Cl contacts are shown as dashed lines.

4. Database survey

Several similar structures have been reported previously, i.e. diethyl 3,3′-(phenylmethylene)bis(1H-indole-2-carboxylate) (Sun et al., 2012), dimethyl 3,3′-[(4-fluorophenyl)methylene]bis(1H-indole-2-carboxylate) (Sun et al., 2015) dimethyl 3,3′-[(4-chlorophenyl) methylene]bis(1H-indole-2-carboxylate) (Li et al., 2014) and dimethyl 3,3′-[(3-fluorophenyl)methylene]bis(1H-indole-2-carboxylate) (Lu et al., 2014). In these structures, the two indole ring systems are also nearly perpendicular to one another, making dihedral angles of 82.0 (5), 84.0 (5), 79.5 (4) and 87.8 (5)°, respectively.

5. Synthesis and crystallization

Ethyl indole-2-carboxylate (1.88 g, 10 mmol) was dissolved in 20 ml ethanol; commercially available 2,4-dichlorobenzaldehyde (0.88 g, 5 mmol) was added and the mixture was heated to reflux temperature. Concentrated HCl (0.5 ml) was added and the reaction was left for 1 h. After cooling, the white product was filtered off and washed thoroughly with ethanol. The reaction was monitored with TLC (AcOEt:hexane = 1:3). Colourless block-like crystals of the title compound suitable for X-ray analysis were obtained in 92% yield by slow evaporation of an ethanol solution.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms were positioned geometrically with N—H = 0.86 Å and C—H = 0.93–0.98 Å, and constrained to ride on their parent atoms with U_iso(H) = xU_eq(C,N), where x = 1.5 for methyl H atoms and 1.2 for all others.

Table 2
Experimental details

Crystal data
Chemical formula	C₂₉H₂₄Cl₂N₂O₄
M_r	535.40
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	9.776 (2), 15.939 (3), 17.581 (4)
β (°)	101.94 (3)
V (Å³)	2680.2 (9)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.28
Crystal size (mm)	0.30 × 0.20 × 0.10

Data collection
Diffractometer	Enraf–Nonius CAD-4
Absorption correction	ψ scan (North et al., 1968 )
T_min, T_max	0.921, 0.973
No. of measured, independent and observed [I > 2σ(I)] reflections	5221, 4917, 2864
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.603

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.067, 0.192, 1.00
No. of reflections	4917
No. of parameters	328
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.69, −1.14
Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994 ), XCAD4 (Harms & Wocadlo, 1995 ), SHELXTL (Sheldrick, 2008 ) and Mercury (Macrae et al., 2008 ).

Supporting information

CCDC reference: 1582719

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989017015730/sj5539sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989017015730/sj5539Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989017015730/sj5539Isup3.cml

checkCIF report

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Diethyl 3,3'-[(2,4-dichlorophenyl)methylidene]bis(1H-indole-2-carboxylate) top

Crystal data top

C₂₉H₂₄Cl₂N₂O₄	F(000) = 1112
M_r = 535.40	D_x = 1.327 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 25 reflections
a = 9.776 (2) Å	θ = 9–13°
b = 15.939 (3) Å	µ = 0.28 mm⁻¹
c = 17.581 (4) Å	T = 293 K
β = 101.94 (3)°	Block, colorless
V = 2680.2 (9) Å³	0.30 × 0.20 × 0.10 mm
Z = 4

Data collection top

Enraf–Nonius CAD-4 diffractometer	2864 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.034
Graphite monochromator	θ_max = 25.4°, θ_min = 1.7°
ω/2θ scans	h = 0→11
Absorption correction: ψ scan (North et al., 1968)	k = 0→19
T_min = 0.921, T_max = 0.973	l = −21→21
5221 measured reflections	3 standard reflections every 200 reflections
4917 independent reflections	intensity decay: 1%

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)] = 0.067	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.192	H-atom parameters constrained
S = 1.00	w = 1/[σ²(F_o²) + (0.1P)² + 0.670P] where P = (F_o² + 2F_c²)/3
4917 reflections	(Δ/σ)_max < 0.001
328 parameters	Δρ_max = 0.69 e Å⁻³
0 restraints	Δρ_min = −1.13 e Å⁻³

Special details top

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.

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 > 2sigma(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

	x	y	z	U_iso*/U_eq
Cl1	0.99326 (13)	0.65116 (9)	0.32372 (10)	0.0997 (6)
O1	0.0795 (3)	0.57429 (17)	−0.06706 (15)	0.0537 (7)
N1	0.1566 (3)	0.53608 (18)	0.09007 (17)	0.0440 (8)
H1A	0.0821	0.5101	0.0675	0.053*
C1	0.4458 (4)	0.6877 (2)	0.0923 (2)	0.0371 (8)
H1B	0.4656	0.6719	0.0418	0.044*
Cl2	0.61986 (13)	0.53457 (7)	0.08076 (8)	0.0813 (5)
O2	0.2675 (3)	0.65654 (16)	−0.05724 (14)	0.0478 (7)
N2	0.3672 (3)	0.91230 (18)	0.04635 (18)	0.0458 (8)
H2A	0.3841	0.9599	0.0272	0.055*
C2	0.3421 (4)	0.6237 (2)	0.1094 (2)	0.0373 (8)
O3	0.6370 (3)	0.77571 (16)	0.01095 (16)	0.0514 (7)
C3	0.3369 (4)	0.5821 (2)	0.1812 (2)	0.0400 (8)
O4	0.6115 (3)	0.91368 (16)	−0.00828 (18)	0.0600 (8)
C4	0.4188 (4)	0.5829 (3)	0.2572 (2)	0.0554 (11)
H4A	0.4952	0.6187	0.2702	0.066*
C5	0.3842 (5)	0.5301 (3)	0.3120 (3)	0.0628 (12)
H5A	0.4388	0.5304	0.3620	0.075*
C6	0.2703 (5)	0.4761 (3)	0.2950 (3)	0.0598 (12)
H6A	0.2510	0.4410	0.3337	0.072*
C7	0.1858 (4)	0.4738 (2)	0.2225 (2)	0.0526 (10)
H7A	0.1089	0.4382	0.2111	0.063*
C8	0.2203 (4)	0.5274 (2)	0.1659 (2)	0.0424 (9)
C9	0.2289 (3)	0.5925 (2)	0.0549 (2)	0.0379 (8)
C10	0.1837 (4)	0.6072 (2)	−0.0283 (2)	0.0378 (8)
C11	0.2406 (5)	0.6680 (3)	−0.1409 (2)	0.0611 (12)
H11A	0.1587	0.7029	−0.1577	0.073*
H11B	0.2245	0.6142	−0.1670	0.073*
C12	0.3646 (5)	0.7087 (3)	−0.1591 (3)	0.080
H12A	0.3509	0.7169	−0.2143	0.120*
H12B	0.4449	0.6737	−0.1418	0.120*
H12C	0.3789	0.7619	−0.1333	0.120*
C13	0.3873 (3)	0.7766 (2)	0.0822 (2)	0.0367 (8)
C14	0.2657 (4)	0.8105 (2)	0.1040 (2)	0.0393 (8)
C15	0.1617 (4)	0.7797 (3)	0.1419 (2)	0.0499 (10)
H15A	0.1632	0.7241	0.1582	0.060*
C16	0.0581 (5)	0.8334 (3)	0.1541 (3)	0.0624 (12)
H16A	−0.0111	0.8133	0.1786	0.075*
C17	0.0542 (5)	0.9170 (3)	0.1308 (3)	0.0755 (14)
H17A	−0.0165	0.9517	0.1409	0.091*
C18	0.1515 (4)	0.9490 (3)	0.0938 (3)	0.0610 (12)
H18A	0.1474	1.0047	0.0776	0.073*
C19	0.2575 (4)	0.8959 (2)	0.0809 (2)	0.0430 (9)
C20	0.4467 (4)	0.8411 (2)	0.0468 (2)	0.0378 (8)
C21	0.5712 (4)	0.8480 (2)	0.0141 (2)	0.0410 (9)
C22	0.7623 (5)	0.7796 (3)	−0.0215 (3)	0.0673 (13)
H22A	0.8306	0.8168	0.0093	0.081*
H22B	0.7397	0.8006	−0.0744	0.081*
C23	0.8196 (6)	0.6929 (4)	−0.0202 (4)	0.113 (2)
H23A	0.9022	0.6932	−0.0417	0.170*
H23B	0.7509	0.6566	−0.0505	0.170*
H23C	0.8427	0.6730	0.0325	0.170*
C24	0.5846 (4)	0.6817 (2)	0.1501 (2)	0.0391 (8)
C25	0.6324 (4)	0.7431 (2)	0.2053 (2)	0.0437 (9)
H25A	0.5790	0.7912	0.2068	0.052*
C26	0.7582 (4)	0.7340 (3)	0.2582 (2)	0.0530 (11)
H26A	0.7885	0.7758	0.2948	0.064*
C27	0.8370 (4)	0.6642 (3)	0.2566 (3)	0.0614 (12)
C28	0.7963 (4)	0.6021 (3)	0.2019 (3)	0.0634 (12)
H28A	0.8513	0.5547	0.2006	0.076*
C29	0.6715 (4)	0.6124 (2)	0.1493 (2)	0.0505 (10)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0617 (8)	0.0762 (9)	0.1361 (13)	−0.0114 (7)	−0.0373 (8)	0.0215 (8)
O1	0.0412 (15)	0.0659 (18)	0.0512 (16)	−0.0065 (14)	0.0034 (13)	0.0008 (14)
N1	0.0394 (17)	0.0439 (18)	0.0467 (18)	−0.0081 (14)	0.0045 (14)	0.0025 (14)
C1	0.0398 (19)	0.0283 (17)	0.043 (2)	0.0036 (15)	0.0076 (16)	−0.0009 (15)
Cl2	0.0746 (8)	0.0529 (7)	0.1067 (10)	0.0220 (6)	−0.0039 (7)	−0.0310 (7)
O2	0.0522 (15)	0.0472 (15)	0.0421 (15)	−0.0103 (13)	0.0050 (12)	0.0081 (12)
N2	0.0482 (18)	0.0284 (15)	0.064 (2)	0.0026 (14)	0.0178 (16)	0.0064 (14)
C2	0.0386 (19)	0.0289 (18)	0.044 (2)	−0.0002 (15)	0.0090 (17)	0.0012 (15)
O3	0.0497 (16)	0.0397 (14)	0.0711 (18)	0.0091 (12)	0.0271 (14)	0.0049 (13)
C3	0.044 (2)	0.0314 (18)	0.044 (2)	0.0024 (16)	0.0090 (17)	0.0068 (16)
O4	0.0536 (17)	0.0404 (15)	0.094 (2)	0.0019 (13)	0.0339 (16)	0.0158 (15)
C4	0.058 (3)	0.056 (2)	0.050 (2)	−0.012 (2)	0.005 (2)	0.005 (2)
C5	0.061 (3)	0.070 (3)	0.054 (3)	−0.003 (2)	0.005 (2)	0.018 (2)
C6	0.063 (3)	0.057 (3)	0.062 (3)	0.001 (2)	0.019 (2)	0.023 (2)
C7	0.050 (2)	0.047 (2)	0.063 (3)	−0.0070 (19)	0.017 (2)	0.011 (2)
C8	0.039 (2)	0.036 (2)	0.053 (2)	0.0003 (16)	0.0113 (17)	0.0015 (17)
C9	0.0347 (18)	0.0327 (18)	0.047 (2)	−0.0003 (15)	0.0107 (16)	0.0019 (16)
C10	0.0344 (19)	0.0329 (18)	0.045 (2)	0.0045 (16)	0.0061 (17)	−0.0003 (16)
C11	0.058 (3)	0.068 (3)	0.052 (3)	−0.007 (2)	−0.002 (2)	0.016 (2)
C12	0.080	0.080	0.080	0.000	0.017	0.000
C13	0.0364 (19)	0.0316 (18)	0.042 (2)	0.0024 (15)	0.0072 (16)	−0.0020 (15)
C14	0.040 (2)	0.0365 (19)	0.043 (2)	0.0038 (16)	0.0105 (16)	−0.0017 (16)
C15	0.046 (2)	0.050 (2)	0.058 (3)	0.0015 (19)	0.021 (2)	0.0061 (19)
C16	0.059 (3)	0.059 (3)	0.078 (3)	0.000 (2)	0.035 (2)	0.002 (2)
C17	0.064 (3)	0.058 (3)	0.114 (4)	0.021 (2)	0.042 (3)	−0.001 (3)
C18	0.056 (3)	0.041 (2)	0.093 (3)	0.012 (2)	0.030 (2)	0.006 (2)
C19	0.040 (2)	0.038 (2)	0.054 (2)	0.0029 (17)	0.0158 (18)	0.0010 (17)
C20	0.0388 (19)	0.0288 (18)	0.046 (2)	−0.0016 (15)	0.0097 (16)	−0.0008 (15)
C21	0.039 (2)	0.039 (2)	0.045 (2)	−0.0015 (17)	0.0076 (17)	0.0001 (17)
C22	0.063 (3)	0.061 (3)	0.089 (3)	0.012 (2)	0.041 (3)	0.002 (2)
C23	0.102 (4)	0.099 (5)	0.158 (6)	0.055 (4)	0.071 (4)	0.029 (4)
C24	0.038 (2)	0.0334 (18)	0.046 (2)	−0.0048 (16)	0.0095 (16)	0.0011 (16)
C25	0.045 (2)	0.0338 (19)	0.052 (2)	−0.0043 (17)	0.0096 (18)	0.0023 (17)
C26	0.060 (3)	0.043 (2)	0.052 (2)	−0.018 (2)	0.004 (2)	0.0031 (18)
C27	0.045 (2)	0.052 (3)	0.080 (3)	−0.008 (2)	−0.006 (2)	0.016 (2)
C28	0.042 (2)	0.046 (2)	0.097 (4)	0.005 (2)	0.001 (2)	0.008 (2)
C29	0.046 (2)	0.034 (2)	0.069 (3)	0.0024 (18)	0.006 (2)	−0.0040 (19)

Geometric parameters (Å, º) top

Cl1—C27	1.738 (4)	C11—H11B	0.9700
O1—C10	1.221 (4)	C12—H12A	0.9600
N1—C8	1.356 (5)	C12—H12B	0.9600
N1—C9	1.368 (4)	C12—H12C	0.9600
N1—H1A	0.8600	C13—C20	1.389 (5)
C1—C2	1.511 (5)	C13—C14	1.429 (5)
C1—C24	1.521 (5)	C14—C15	1.414 (5)
C1—C13	1.525 (4)	C14—C19	1.418 (5)
C1—H1B	0.9800	C15—C16	1.377 (5)
Cl2—C29	1.730 (4)	C15—H15A	0.9300
O2—C10	1.312 (4)	C16—C17	1.392 (6)
O2—C11	1.450 (5)	C16—H16A	0.9300
N2—C19	1.363 (4)	C17—C18	1.358 (6)
N2—C20	1.375 (4)	C17—H17A	0.9300
N2—H2A	0.8600	C18—C19	1.393 (5)
C2—C9	1.396 (5)	C18—H18A	0.9300
C2—C3	1.436 (5)	C20—C21	1.454 (5)
O3—C21	1.327 (4)	C22—C23	1.489 (7)
O3—C22	1.456 (5)	C22—H22A	0.9700
C3—C4	1.409 (5)	C22—H22B	0.9700
C3—C8	1.415 (5)	C23—H23A	0.9600
O4—C21	1.212 (4)	C23—H23B	0.9600
C4—C5	1.372 (5)	C23—H23C	0.9600
C4—H4A	0.9300	C24—C25	1.389 (5)
C5—C6	1.390 (6)	C24—C29	1.396 (5)
C5—H5A	0.9300	C25—C26	1.388 (5)
C6—C7	1.369 (6)	C25—H25A	0.9300
C6—H6A	0.9300	C26—C27	1.358 (6)
C7—C8	1.405 (5)	C26—H26A	0.9300
C7—H7A	0.9300	C27—C28	1.380 (6)
C9—C10	1.457 (5)	C28—C29	1.380 (5)
C11—C12	1.467 (6)	C28—H28A	0.9300
C11—H11A	0.9700

C8—N1—C9	109.6 (3)	C14—C13—C1	129.2 (3)
C8—N1—H1A	125.2	C15—C14—C19	117.7 (3)
C9—N1—H1A	125.2	C15—C14—C13	135.6 (3)
C2—C1—C24	111.6 (3)	C19—C14—C13	106.7 (3)
C2—C1—C13	113.6 (3)	C16—C15—C14	118.8 (4)
C24—C1—C13	113.4 (3)	C16—C15—H15A	120.6
C2—C1—H1B	105.8	C14—C15—H15A	120.6
C24—C1—H1B	105.8	C15—C16—C17	121.7 (4)
C13—C1—H1B	105.8	C15—C16—H16A	119.1
C10—O2—C11	118.2 (3)	C17—C16—H16A	119.1
C19—N2—C20	109.6 (3)	C18—C17—C16	121.4 (4)
C19—N2—H2A	125.2	C18—C17—H17A	119.3
C20—N2—H2A	125.2	C16—C17—H17A	119.3
C9—C2—C3	105.7 (3)	C17—C18—C19	117.9 (4)
C9—C2—C1	125.0 (3)	C17—C18—H18A	121.0
C3—C2—C1	129.3 (3)	C19—C18—H18A	121.0
C21—O3—C22	115.8 (3)	N2—C19—C18	129.6 (3)
C4—C3—C8	117.6 (3)	N2—C19—C14	108.0 (3)
C4—C3—C2	135.5 (3)	C18—C19—C14	122.5 (3)
C8—C3—C2	106.9 (3)	N2—C20—C13	109.0 (3)
C5—C4—C3	119.1 (4)	N2—C20—C21	117.0 (3)
C5—C4—H4A	120.5	C13—C20—C21	134.0 (3)
C3—C4—H4A	120.5	O4—C21—O3	122.9 (3)
C4—C5—C6	122.2 (4)	O4—C21—C20	123.3 (3)
C4—C5—H5A	118.9	O3—C21—C20	113.8 (3)
C6—C5—H5A	118.9	O3—C22—C23	107.4 (4)
C7—C6—C5	121.2 (4)	O3—C22—H22A	110.2
C7—C6—H6A	119.4	C23—C22—H22A	110.2
C5—C6—H6A	119.4	O3—C22—H22B	110.2
C6—C7—C8	117.2 (4)	C23—C22—H22B	110.2
C6—C7—H7A	121.4	H22A—C22—H22B	108.5
C8—C7—H7A	121.4	C22—C23—H23A	109.5
N1—C8—C7	129.0 (3)	C22—C23—H23B	109.5
N1—C8—C3	108.2 (3)	H23A—C23—H23B	109.5
C7—C8—C3	122.8 (4)	C22—C23—H23C	109.5
N1—C9—C2	109.6 (3)	H23A—C23—H23C	109.5
N1—C9—C10	118.8 (3)	H23B—C23—H23C	109.5
C2—C9—C10	131.6 (3)	C25—C24—C29	116.6 (3)
O1—C10—O2	123.8 (3)	C25—C24—C1	123.2 (3)
O1—C10—C9	122.4 (3)	C29—C24—C1	120.2 (3)
O2—C10—C9	113.7 (3)	C26—C25—C24	121.2 (4)
O2—C11—C12	107.0 (3)	C26—C25—H25A	119.4
O2—C11—H11A	110.3	C24—C25—H25A	119.4
C12—C11—H11A	110.3	C27—C26—C25	120.0 (4)
O2—C11—H11B	110.3	C27—C26—H26A	120.0
C12—C11—H11B	110.3	C25—C26—H26A	120.0
H11A—C11—H11B	108.6	C26—C27—C28	121.3 (4)
C11—C12—H12A	109.5	C26—C27—Cl1	120.4 (4)
C11—C12—H12B	109.5	C28—C27—Cl1	118.3 (3)
H12A—C12—H12B	109.5	C29—C28—C27	118.0 (4)
C11—C12—H12C	109.5	C29—C28—H28A	121.0
H12A—C12—H12C	109.5	C27—C28—H28A	121.0
H12B—C12—H12C	109.5	C28—C29—C24	122.9 (4)
C20—C13—C14	106.8 (3)	C28—C29—Cl2	118.1 (3)
C20—C13—C1	124.0 (3)	C24—C29—Cl2	119.0 (3)

C24—C1—C2—C9	−156.0 (3)	C13—C14—C15—C16	178.9 (4)
C13—C1—C2—C9	74.3 (4)	C14—C15—C16—C17	−0.6 (7)
C24—C1—C2—C3	23.5 (5)	C15—C16—C17—C18	1.1 (8)
C13—C1—C2—C3	−106.2 (4)	C16—C17—C18—C19	−1.1 (8)
C9—C2—C3—C4	178.7 (4)	C20—N2—C19—C18	179.4 (4)
C1—C2—C3—C4	−0.9 (7)	C20—N2—C19—C14	−0.5 (4)
C9—C2—C3—C8	0.3 (4)	C17—C18—C19—N2	−179.2 (4)
C1—C2—C3—C8	−179.3 (3)	C17—C18—C19—C14	0.7 (7)
C8—C3—C4—C5	1.4 (6)	C15—C14—C19—N2	179.6 (3)
C2—C3—C4—C5	−176.9 (4)	C13—C14—C19—N2	0.6 (4)
C3—C4—C5—C6	−0.5 (7)	C15—C14—C19—C18	−0.3 (6)
C4—C5—C6—C7	−0.6 (7)	C13—C14—C19—C18	−179.4 (4)
C5—C6—C7—C8	0.7 (6)	C19—N2—C20—C13	0.2 (4)
C9—N1—C8—C7	−176.9 (4)	C19—N2—C20—C21	−178.2 (3)
C9—N1—C8—C3	1.5 (4)	C14—C13—C20—N2	0.1 (4)
C6—C7—C8—N1	178.5 (4)	C1—C13—C20—N2	179.2 (3)
C6—C7—C8—C3	0.3 (6)	C14—C13—C20—C21	178.2 (4)
C4—C3—C8—N1	−179.8 (3)	C1—C13—C20—C21	−2.7 (6)
C2—C3—C8—N1	−1.1 (4)	C22—O3—C21—O4	0.0 (5)
C4—C3—C8—C7	−1.3 (5)	C22—O3—C21—C20	180.0 (3)
C2—C3—C8—C7	177.5 (3)	N2—C20—C21—O4	4.9 (5)
C8—N1—C9—C2	−1.4 (4)	C13—C20—C21—O4	−173.1 (4)
C8—N1—C9—C10	176.0 (3)	N2—C20—C21—O3	−175.1 (3)
C3—C2—C9—N1	0.6 (4)	C13—C20—C21—O3	7.0 (6)
C1—C2—C9—N1	−179.7 (3)	C21—O3—C22—C23	−179.8 (4)
C3—C2—C9—C10	−176.2 (3)	C2—C1—C24—C25	−110.9 (4)
C1—C2—C9—C10	3.4 (6)	C13—C1—C24—C25	18.9 (5)
C11—O2—C10—O1	−4.5 (5)	C2—C1—C24—C29	69.4 (4)
C11—O2—C10—C9	173.4 (3)	C13—C1—C24—C29	−160.8 (3)
N1—C9—C10—O1	3.8 (5)	C29—C24—C25—C26	−2.0 (5)
C2—C9—C10—O1	−179.5 (4)	C1—C24—C25—C26	178.3 (3)
N1—C9—C10—O2	−174.1 (3)	C24—C25—C26—C27	0.0 (6)
C2—C9—C10—O2	2.5 (5)	C25—C26—C27—C28	1.5 (6)
C10—O2—C11—C12	−167.2 (3)	C25—C26—C27—Cl1	−178.8 (3)
C2—C1—C13—C20	−162.4 (3)	C26—C27—C28—C29	−0.9 (7)
C24—C1—C13—C20	68.8 (4)	Cl1—C27—C28—C29	179.4 (3)
C2—C1—C13—C14	16.4 (5)	C27—C28—C29—C24	−1.2 (7)
C24—C1—C13—C14	−112.3 (4)	C27—C28—C29—Cl2	−179.8 (3)
C20—C13—C14—C15	−179.2 (4)	C25—C24—C29—C28	2.6 (6)
C1—C13—C14—C15	1.8 (7)	C1—C24—C29—C28	−177.7 (4)
C20—C13—C14—C19	−0.4 (4)	C25—C24—C29—Cl2	−178.8 (3)
C1—C13—C14—C19	−179.4 (3)	C1—C24—C29—Cl2	0.9 (5)
C19—C14—C15—C16	0.2 (6)

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg5 are the centroids of the N1,C8,C3,C2,C9 and C24–C29 rings respectively.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1ⁱ	0.86	2.07	2.864 (4)	152
N2—H2A···O4ⁱⁱ	0.86	2.04	2.871 (4)	161
C11—H11A···Cl1ⁱⁱⁱ	0.97	2.81	3.731 (5)	158
C4—H4A···Cg5	0.93	2.77	3.516 (4)	137
C15—H15A···Cg1	0.93	2.72	3.476 (5)	139

Symmetry codes: (i) −x, −y+1, −z; (ii) −x+1, −y+2, −z; (iii) x−1, −y+3/2, z−1/2.

Acknowledgements

The authors thank the Center of Testing and Analysis, Nanjing University, for support.

Funding information

Funding for this research was provided by: University of Natural Science Foundation in Jiangsu Province (grant No. 17KJB320001); Top-notch Academic Programs Project of Jiangsu Higher Education Institutions (grant No. PPZY2015B179); Training program of Students innovation and entrepreneurship in Jiangsu Province (grant No. 201712920001Y); Qing Lan Project of Jiangsu Province.

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