Synthesis, crystal structures and anti­proliferative activities of a new indole-containing dipyridyl­methanone hydrazone Schiff base and its cadmium(II) com­plex

Zhang, Q.; Wang, Z.-Q.; Xing, D.-X.; Wang, S.-J.; Tan, X.-J.

doi:10.1107/S2053229624010167

Synthesis, crystal structures and antiproliferative activities of a new indole-containing dipyridylmethanone hydrazone Schiff base and its cadmium(II) complex

Q. Zhang, Z.-Q. Wang, D.-X. Xing, S.-J. Wang and X.-J. Tan

In this study, we introduce a novel indole-containing pyridine-based Schiff base, (E)-2-({[bis(pyridin-2-yl)methylidene]hydrazin-1-ylidene}methyl)-1H-indole, C₂₀H₁₅N₅ (2-DPHI), and its cadmium(II) complex poly[[2-({[bis(pyridin-2-yl)methylidene]hydrazin-1-ylidene}methyl)-1H-indole]di-μ-chlorido-cadmium(II)], [CdCl₂(C₂₀H₁₅N₅)]_n (pCd2), as potential anticancer agents. The Schiff base was synthesized by reacting dipyridylmethanone hydrazone with indole-2-formaldehyde, while the cadmium complex was prepared by combining CdCl₂ and 2-DPHI in methanol at room temperature. Both compounds were evaluated for their cytotoxicity against three human cancer cell lines (A375, A549 and HeLa) and a normal cell line (HFF-1). The ligand 2-DPHI exhibited notable antitumour activity, with an IC₅₀ value of 12.22 µM against A375 and 15.17 µM against A549 after 48 h, while the pCd2 complex showed an even stronger inhibition of A375 cells, with an IC₅₀ value of 4.88 µM, outperforming both 2-DPHI and CdCl₂. Both compounds demonstrated lower toxicity towards normal cells compared to cancer cells. The structures of 2-DPHI and pCd2 were fully characterized using single-crystal X-ray diffraction, elemental analysis, high-resolution mass spectrometry and FT–IR, ¹H NMR, ¹³C NMR and UV–Vis spectroscopy.

Keywords: crystal structure; indole; dipyridylmethanone hydrazone; Schiff base; cadmium(II); antiproliferative activity.

Read article Similar articles

Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S2053229624010167/oj3023sup1.cif Contains datablocks 2-DPHI, pCd2, global
	Chemical Markup Language (CML) file https://doi.org/10.1107/S2053229624010167/oj30232-DPHIsup4.cml Supplementary material
	Structure factor file (CIF format) https://doi.org/10.1107/S2053229624010167/oj30232-DPHIsup2.hkl Contains datablock 2-DPHI
	Structure factor file (CIF format) https://doi.org/10.1107/S2053229624010167/oj3023pCd2sup3.hkl Contains datablock pCd2
	Portable Document Format (PDF) file https://doi.org/10.1107/S2053229624010167/oj3023sup5.pdf Supplementary material

CCDC references: 2392155; 2392154

Computing details top

(E)-2-({[Bis(pyridin-2-yl)methylidene]hydrazin-1-ylidene}methyl)-1H-indole (2-DPHI) top

Crystal data top

C₂₀H₁₅N₅	D_x = 1.296 Mg m⁻³
M_r = 325.37	Melting point: 454(2) K
Orthorhombic, Pbc2₁	Mo Kα radiation, λ = 0.71073 Å
a = 4.8448 (2) Å	Cell parameters from 380 reflections
b = 25.9645 (12) Å	θ = 2.5–26.0°
c = 26.5071 (11) Å	µ = 0.08 mm⁻¹
V = 3334.4 (2) Å³	T = 293 K
Z = 8	Block, yellow
F(000) = 1360	0.35 × 0.26 × 0.18 mm

Data collection top

Bruker SMART CCD area detector diffractometer	4373 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.070
phi and ω scans	θ_max = 26.4°, θ_min = 3.2°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −6→5
T_min = 0.975, T_max = 0.986	k = −32→32
37250 measured reflections	l = −33→33
6783 independent reflections

Refinement top

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)] = 0.056	w = 1/[σ²(F_o²) + (0.0686P)²] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.148	(Δ/σ)_max < 0.001
S = 0.99	Δρ_max = 0.22 e Å⁻³
6783 reflections	Δρ_min = −0.19 e Å⁻³
459 parameters	Absolute structure: Flack x determined using 1587 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
1 restraint	Absolute structure parameter: −0.6 (10)

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.5103 (10)	0.36082 (19)	0.52405 (18)	0.0451 (11)
C1A	0.9955 (9)	0.57995 (19)	0.65181 (17)	0.0429 (11)
C2	0.4897 (10)	0.4028 (2)	0.55471 (18)	0.0495 (12)
H2	0.5924	0.4087	0.5838	0.059*
C2A	1.0194 (10)	0.6196 (2)	0.61838 (18)	0.0494 (12)
H2A	0.9205	0.6235	0.5885	0.059*
C3	0.2850 (9)	0.43608 (18)	0.53464 (17)	0.0440 (11)
C3A	1.2233 (10)	0.65398 (18)	0.63737 (18)	0.0460 (12)
C4	0.1763 (11)	0.4840 (2)	0.5481 (2)	0.0561 (14)
H4	0.2374	0.5007	0.5771	0.067*
C4A	1.3292 (11)	0.7015 (2)	0.6214 (2)	0.0620 (15)
H4A	1.2672	0.7166	0.5917	0.074*
C5	−0.0221 (11)	0.5061 (2)	0.5181 (2)	0.0602 (14)
H5	−0.0905	0.5385	0.5263	0.072*
C5A	1.5251 (12)	0.7253 (2)	0.6503 (2)	0.0708 (17)
H5A	1.5932	0.7573	0.6406	0.085*
C6	−0.1222 (11)	0.4809 (2)	0.4757 (2)	0.0543 (14)
H6	−0.2599	0.4965	0.4566	0.065*
C6A	1.6247 (13)	0.7015 (3)	0.6946 (2)	0.0691 (18)
H6A	1.7633	0.7177	0.7130	0.083*
C7	−0.0228 (10)	0.4334 (2)	0.46122 (18)	0.0516 (13)
H7	−0.0905	0.4165	0.4328	0.062*
C7A	1.5234 (11)	0.6558 (2)	0.71100 (19)	0.0535 (13)
H7A	1.5884	0.6409	0.7406	0.064*
C8	0.1826 (9)	0.41189 (19)	0.49086 (18)	0.0415 (12)
C8A	1.3211 (9)	0.63213 (18)	0.68261 (17)	0.0409 (11)
C9	0.7005 (11)	0.3183 (2)	0.5251 (2)	0.0489 (12)
C9A	0.8070 (10)	0.53721 (19)	0.65111 (18)	0.0465 (12)
H9A	0.6958	0.5318	0.6230	0.056*
C10	1.0073 (9)	0.23255 (17)	0.45278 (17)	0.0426 (11)
C10A	0.4881 (9)	0.45259 (18)	0.72424 (17)	0.0444 (11)
C11	0.9581 (9)	0.25950 (18)	0.40385 (18)	0.0413 (11)
C11A	0.5331 (9)	0.48062 (19)	0.77260 (17)	0.0434 (12)
C12	0.7753 (10)	0.2420 (2)	0.3685 (2)	0.0610 (15)
H12	0.6751	0.2120	0.3740	0.073*
C12A	0.7167 (10)	0.4636 (2)	0.8087 (2)	0.0616 (14)
H12A	0.8193	0.4338	0.8036	0.074*
C13	0.7421 (12)	0.2697 (3)	0.3243 (2)	0.0663 (17)
H13	0.6122	0.2595	0.3005	0.080*
C13A	0.7450 (12)	0.4919 (3)	0.8529 (2)	0.0686 (17)
H13A	0.8690	0.4818	0.8778	0.082*
C14	0.9037 (13)	0.3125 (3)	0.3161 (2)	0.0675 (17)
H14	0.8924	0.3310	0.2861	0.081*
C14A	0.5887 (14)	0.5346 (3)	0.8590 (2)	0.0678 (16)
H14A	0.5999	0.5538	0.8886	0.081*
C15	1.0805 (13)	0.3268 (2)	0.3534 (2)	0.0658 (15)
H15	1.1874	0.3560	0.3481	0.079*
C15A	0.4149 (13)	0.5490 (2)	0.8213 (2)	0.0668 (15)
H15A	0.3082	0.5784	0.8259	0.080*
C16	1.1919 (10)	0.18714 (17)	0.4538 (2)	0.0462 (11)
C16A	0.3026 (10)	0.40739 (18)	0.72329 (19)	0.0471 (12)
C17	1.3224 (11)	0.1720 (2)	0.4978 (2)	0.0557 (14)
H17	1.2968	0.1900	0.5278	0.067*
C17A	0.1734 (13)	0.3910 (2)	0.6802 (2)	0.0611 (15)
C18	1.4930 (12)	0.1290 (2)	0.4958 (3)	0.0679 (16)
H18	1.5848	0.1177	0.5246	0.081*
C18A	0.0027 (12)	0.3484 (2)	0.6817 (3)	0.0721 (17)
H18A	−0.0881	0.3371	0.6528	0.087*
C19	1.5240 (12)	0.1036 (2)	0.4508 (3)	0.0683 (16)
H19	1.6381	0.0749	0.4486	0.082*
C19A	−0.0289 (12)	0.3233 (2)	0.7267 (3)	0.0722 (17)
H19A	−0.1404	0.2943	0.7292	0.087*
C20	1.3857 (13)	0.1208 (2)	0.4095 (3)	0.0715 (17)
H20	1.4049	0.1025	0.3796	0.086*
C20A	0.1083 (13)	0.3422 (2)	0.7680 (3)	0.0733 (17)
H20A	0.0870	0.3249	0.7985	0.088*
N1	0.3240 (7)	0.36618 (15)	0.48493 (15)	0.0448 (9)
H1	0.3000	0.3445	0.4608	0.054*
N1A	1.1799 (8)	0.58679 (16)	0.69029 (15)	0.0454 (10)
H1A	1.2038	0.5661	0.7153	0.055*
N2	0.7073 (8)	0.28769 (17)	0.48846 (16)	0.0502 (11)
N2A	0.7909 (8)	0.50676 (16)	0.68852 (15)	0.0502 (10)
N3	0.8999 (9)	0.24691 (16)	0.49465 (15)	0.0507 (10)
N3A	0.6034 (9)	0.46654 (16)	0.68247 (16)	0.0536 (11)
N4	1.1120 (9)	0.30182 (15)	0.39720 (15)	0.0501 (10)
N4A	0.3891 (10)	0.52358 (17)	0.77842 (16)	0.0534 (11)
N5	1.2222 (9)	0.16288 (16)	0.40940 (18)	0.0609 (12)
N5A	0.2705 (9)	0.38381 (17)	0.76738 (18)	0.0627 (12)
H9	0.820 (8)	0.3177 (17)	0.5508 (17)	0.040 (12)*
H17A	0.194 (10)	0.408 (2)	0.653 (2)	0.059 (16)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.053 (3)	0.048 (3)	0.034 (2)	0.002 (2)	0.007 (2)	0.000 (2)
C1A	0.046 (3)	0.046 (3)	0.036 (2)	0.001 (2)	−0.001 (2)	0.002 (2)
C2	0.054 (3)	0.059 (3)	0.036 (2)	0.003 (3)	0.003 (2)	−0.011 (2)
C2A	0.060 (3)	0.052 (3)	0.036 (3)	−0.004 (3)	−0.004 (2)	0.005 (2)
C3	0.049 (3)	0.044 (3)	0.039 (3)	−0.003 (2)	0.012 (2)	−0.007 (2)
C3A	0.056 (3)	0.038 (3)	0.044 (3)	0.003 (2)	0.008 (2)	0.001 (2)
C4	0.058 (3)	0.050 (3)	0.060 (3)	−0.001 (3)	0.010 (3)	−0.015 (3)
C4A	0.076 (4)	0.050 (3)	0.060 (3)	−0.004 (3)	0.008 (3)	0.014 (3)
C5	0.061 (3)	0.051 (3)	0.069 (3)	0.011 (3)	0.015 (3)	−0.001 (3)
C5A	0.084 (4)	0.048 (3)	0.081 (4)	−0.017 (3)	0.015 (4)	−0.001 (3)
C6	0.058 (3)	0.053 (3)	0.052 (3)	0.011 (3)	0.006 (3)	0.011 (3)
C6A	0.075 (4)	0.067 (4)	0.064 (4)	−0.019 (3)	0.003 (3)	−0.010 (3)
C7	0.055 (3)	0.060 (3)	0.039 (3)	−0.003 (3)	0.007 (2)	0.000 (3)
C7A	0.059 (3)	0.057 (3)	0.045 (3)	−0.003 (3)	0.000 (2)	−0.007 (3)
C8	0.046 (3)	0.041 (3)	0.037 (3)	−0.003 (2)	0.013 (2)	−0.003 (2)
C8A	0.043 (3)	0.042 (3)	0.038 (2)	0.001 (2)	0.005 (2)	−0.005 (2)
C9	0.059 (3)	0.049 (3)	0.038 (3)	0.006 (3)	0.007 (3)	0.006 (3)
C9A	0.057 (3)	0.049 (3)	0.033 (3)	−0.009 (2)	0.005 (2)	−0.002 (2)
C10	0.056 (3)	0.034 (3)	0.038 (2)	0.000 (2)	0.009 (2)	−0.002 (2)
C10A	0.056 (3)	0.035 (3)	0.043 (3)	−0.004 (2)	0.009 (2)	−0.001 (2)
C11	0.052 (3)	0.034 (3)	0.038 (3)	0.013 (2)	0.004 (2)	−0.005 (2)
C11A	0.053 (3)	0.039 (3)	0.038 (3)	−0.007 (2)	0.008 (2)	0.007 (2)
C12	0.061 (3)	0.056 (4)	0.065 (4)	−0.012 (3)	0.004 (3)	−0.015 (3)
C12A	0.063 (3)	0.060 (4)	0.062 (4)	0.005 (3)	−0.002 (3)	0.007 (3)
C13	0.069 (4)	0.086 (5)	0.044 (3)	0.015 (3)	−0.012 (3)	−0.013 (3)
C13A	0.072 (4)	0.087 (5)	0.047 (3)	−0.012 (4)	−0.015 (3)	0.010 (3)
C14	0.085 (4)	0.076 (4)	0.042 (3)	0.029 (4)	−0.001 (3)	0.004 (3)
C14A	0.090 (4)	0.063 (4)	0.050 (3)	−0.019 (4)	−0.003 (3)	−0.007 (3)
C15	0.094 (4)	0.045 (3)	0.059 (4)	−0.002 (3)	−0.004 (3)	0.013 (3)
C15A	0.093 (4)	0.058 (4)	0.050 (3)	0.005 (3)	−0.001 (3)	−0.009 (3)
C16	0.056 (3)	0.033 (3)	0.050 (3)	0.002 (2)	0.011 (3)	0.004 (2)
C16A	0.055 (3)	0.036 (3)	0.050 (3)	0.001 (2)	0.015 (2)	−0.005 (2)
C17	0.066 (3)	0.042 (3)	0.059 (3)	0.003 (3)	0.000 (3)	0.006 (3)
C17A	0.078 (4)	0.053 (4)	0.052 (4)	−0.012 (3)	0.004 (3)	0.000 (3)
C18	0.077 (4)	0.049 (4)	0.078 (4)	0.009 (3)	−0.001 (3)	0.010 (3)
C18A	0.079 (4)	0.065 (4)	0.073 (4)	−0.022 (3)	0.003 (3)	−0.011 (4)
C19	0.074 (4)	0.041 (3)	0.090 (4)	0.016 (3)	0.013 (4)	0.008 (3)
C19A	0.079 (4)	0.046 (3)	0.092 (5)	−0.020 (3)	0.006 (4)	−0.003 (4)
C20	0.090 (4)	0.053 (4)	0.071 (4)	0.017 (3)	0.011 (4)	−0.007 (3)
C20A	0.105 (5)	0.046 (3)	0.068 (4)	−0.021 (3)	0.021 (4)	0.006 (3)
N1	0.054 (2)	0.043 (2)	0.038 (2)	0.0003 (19)	0.003 (2)	−0.0100 (18)
N1A	0.052 (2)	0.050 (2)	0.034 (2)	−0.003 (2)	0.0019 (19)	0.0041 (19)
N2	0.064 (3)	0.047 (3)	0.039 (2)	0.007 (2)	0.010 (2)	−0.005 (2)
N2A	0.056 (2)	0.053 (3)	0.041 (2)	−0.014 (2)	0.0078 (19)	0.001 (2)
N3	0.065 (3)	0.039 (2)	0.047 (2)	0.011 (2)	0.007 (2)	0.003 (2)
N3A	0.064 (3)	0.051 (3)	0.046 (2)	−0.016 (2)	0.013 (2)	−0.002 (2)
N4	0.065 (3)	0.038 (2)	0.048 (2)	−0.004 (2)	−0.004 (2)	0.005 (2)
N4A	0.075 (3)	0.042 (3)	0.043 (3)	0.003 (2)	−0.007 (2)	−0.001 (2)
N5	0.082 (3)	0.044 (3)	0.057 (3)	0.018 (2)	0.011 (2)	−0.003 (2)
N5A	0.086 (3)	0.045 (3)	0.057 (3)	−0.013 (2)	0.012 (3)	0.005 (2)

Geometric parameters (Å, º) top

C1—C2	1.364 (6)	C11—C12	1.367 (7)
C1—N1	1.382 (6)	C11A—N4A	1.325 (6)
C1—C9	1.437 (7)	C11A—C12A	1.379 (7)
C1A—C2A	1.363 (7)	C12—C13	1.383 (8)
C1A—N1A	1.368 (6)	C12—H12	0.9300
C1A—C9A	1.437 (7)	C12A—C13A	1.391 (8)
C2—C3	1.419 (7)	C12A—H12A	0.9300
C2—H2	0.9300	C13—C14	1.377 (8)
C2A—C3A	1.424 (7)	C13—H13	0.9300
C2A—H2A	0.9300	C13A—C14A	1.351 (8)
C3—C4	1.397 (7)	C13A—H13A	0.9300
C3—C8	1.410 (7)	C14—C15	1.360 (8)
C3A—C4A	1.401 (7)	C14—H14	0.9300
C3A—C8A	1.409 (6)	C14A—C15A	1.360 (8)
C4—C5	1.374 (8)	C14A—H14A	0.9300
C4—H4	0.9300	C15—N4	1.338 (7)
C4A—C5A	1.366 (8)	C15—H15	0.9300
C4A—H4A	0.9300	C15A—N4A	1.320 (7)
C5—C6	1.387 (8)	C15A—H15A	0.9300
C5—H5	0.9300	C16—N5	1.343 (7)
C5A—C6A	1.413 (8)	C16—C17	1.385 (7)
C5A—H5A	0.9300	C16A—N5A	1.329 (6)
C6—C7	1.379 (7)	C16A—C17A	1.370 (7)
C6—H6	0.9300	C17—C18	1.389 (7)
C6A—C7A	1.355 (8)	C17—H17	0.9300
C6A—H6A	0.9300	C17A—C18A	1.382 (8)
C7—C8	1.385 (7)	C17A—H17A	0.85 (5)
C7—H7	0.9300	C18—C19	1.372 (8)
C7A—C8A	1.381 (7)	C18—H18	0.9300
C7A—H7A	0.9300	C18A—C19A	1.367 (9)
C8—N1	1.380 (6)	C18A—H18A	0.9300
C8A—N1A	1.377 (6)	C19—C20	1.359 (9)
C9—N2	1.256 (6)	C19—H19	0.9300
C9—H9	0.89 (4)	C19A—C20A	1.372 (9)
C9A—N2A	1.271 (6)	C19A—H19A	0.9300
C9A—H9A	0.9300	C20—N5	1.349 (7)
C10—N3	1.281 (6)	C20—H20	0.9300
C10—C16	1.480 (6)	C20A—N5A	1.336 (7)
C10—C11	1.493 (6)	C20A—H20A	0.9300
C10A—N3A	1.292 (6)	N1—H1	0.8600
C10A—C16A	1.478 (6)	N1A—H1A	0.8600
C10A—C11A	1.490 (7)	N2—N3	1.421 (6)
C11—N4	1.340 (6)	N2A—N3A	1.393 (5)

C2—C1—N1	108.6 (4)	C11—C12—H12	120.6
C2—C1—C9	130.5 (5)	C13—C12—H12	120.6
N1—C1—C9	120.7 (4)	C11A—C12A—C13A	118.6 (5)
C2A—C1A—N1A	109.4 (4)	C11A—C12A—H12A	120.7
C2A—C1A—C9A	128.9 (4)	C13A—C12A—H12A	120.7
N1A—C1A—C9A	121.7 (4)	C14—C13—C12	119.2 (5)
C1—C2—C3	108.3 (4)	C14—C13—H13	120.4
C1—C2—H2	125.8	C12—C13—H13	120.4
C3—C2—H2	125.8	C14A—C13A—C12A	118.7 (5)
C1A—C2A—C3A	107.6 (4)	C14A—C13A—H13A	120.7
C1A—C2A—H2A	126.2	C12A—C13A—H13A	120.7
C3A—C2A—H2A	126.2	C15—C14—C13	117.5 (5)
C4—C3—C8	118.3 (5)	C15—C14—H14	121.2
C4—C3—C2	135.2 (5)	C13—C14—H14	121.2
C8—C3—C2	106.5 (4)	C13A—C14A—C15A	118.9 (6)
C4A—C3A—C8A	119.2 (5)	C13A—C14A—H14A	120.5
C4A—C3A—C2A	134.4 (5)	C15A—C14A—H14A	120.5
C8A—C3A—C2A	106.4 (4)	N4—C15—C14	124.8 (6)
C5—C4—C3	119.2 (5)	N4—C15—H15	117.6
C5—C4—H4	120.4	C14—C15—H15	117.6
C3—C4—H4	120.4	N4A—C15A—C14A	123.6 (6)
C5A—C4A—C3A	118.9 (5)	N4A—C15A—H15A	118.2
C5A—C4A—H4A	120.6	C14A—C15A—H15A	118.2
C3A—C4A—H4A	120.6	N5—C16—C17	123.8 (4)
C4—C5—C6	121.2 (5)	N5—C16—C10	115.1 (4)
C4—C5—H5	119.4	C17—C16—C10	121.2 (5)
C6—C5—H5	119.4	N5A—C16A—C17A	122.5 (5)
C4A—C5A—C6A	120.4 (5)	N5A—C16A—C10A	115.0 (5)
C4A—C5A—H5A	119.8	C17A—C16A—C10A	122.5 (5)
C6A—C5A—H5A	119.8	C16—C17—C18	117.9 (5)
C7—C6—C5	121.6 (5)	C16—C17—H17	121.1
C7—C6—H6	119.2	C18—C17—H17	121.1
C5—C6—H6	119.2	C16A—C17A—C18A	119.9 (6)
C7A—C6A—C5A	121.7 (6)	C16A—C17A—H17A	119 (4)
C7A—C6A—H6A	119.2	C18A—C17A—H17A	121 (4)
C5A—C6A—H6A	119.2	C19—C18—C17	119.0 (6)
C6—C7—C8	117.0 (5)	C19—C18—H18	120.5
C6—C7—H7	121.5	C17—C18—H18	120.5
C8—C7—H7	121.5	C19A—C18A—C17A	118.2 (6)
C6A—C7A—C8A	118.2 (5)	C19A—C18A—H18A	120.9
C6A—C7A—H7A	120.9	C17A—C18A—H18A	120.9
C8A—C7A—H7A	120.9	C20—C19—C18	119.2 (5)
N1—C8—C7	129.7 (5)	C20—C19—H19	120.4
N1—C8—C3	107.6 (4)	C18—C19—H19	120.4
C7—C8—C3	122.7 (5)	C18A—C19A—C20A	118.2 (5)
N1A—C8A—C7A	130.8 (5)	C18A—C19A—H19A	120.9
N1A—C8A—C3A	107.6 (4)	C20A—C19A—H19A	120.9
C7A—C8A—C3A	121.5 (5)	N5—C20—C19	123.9 (6)
N2—C9—C1	119.2 (5)	N5—C20—H20	118.0
N2—C9—H9	124 (3)	C19—C20—H20	118.0
C1—C9—H9	116 (3)	N5A—C20A—C19A	124.3 (6)
N2A—C9A—C1A	120.6 (4)	N5A—C20A—H20A	117.8
N2A—C9A—H9A	119.7	C19A—C20A—H20A	117.8
C1A—C9A—H9A	119.7	C8—N1—C1	109.0 (4)
N3—C10—C16	117.5 (4)	C8—N1—H1	125.5
N3—C10—C11	123.4 (4)	C1—N1—H1	125.5
C16—C10—C11	119.1 (4)	C1A—N1A—C8A	109.0 (4)
N3A—C10A—C16A	118.1 (4)	C1A—N1A—H1A	125.5
N3A—C10A—C11A	122.5 (4)	C8A—N1A—H1A	125.5
C16A—C10A—C11A	119.4 (4)	C9—N2—N3	113.6 (4)
N4—C11—C12	122.9 (5)	C9A—N2A—N3A	114.6 (4)
N4—C11—C10	114.2 (4)	C10—N3—N2	112.6 (4)
C12—C11—C10	122.9 (5)	C10A—N3A—N2A	113.2 (4)
N4A—C11A—C12A	121.9 (5)	C15—N4—C11	116.6 (5)
N4A—C11A—C10A	115.7 (4)	C15A—N4A—C11A	118.1 (5)
C12A—C11A—C10A	122.3 (5)	C16—N5—C20	116.2 (5)
C11—C12—C13	118.9 (5)	C16A—N5A—C20A	116.9 (5)

N1—C1—C2—C3	−0.1 (6)	C12A—C13A—C14A—C15A	−1.7 (9)
C9—C1—C2—C3	174.1 (5)	C13—C14—C15—N4	1.1 (9)
N1A—C1A—C2A—C3A	−1.8 (6)	C13A—C14A—C15A—N4A	−0.1 (10)
C9A—C1A—C2A—C3A	176.0 (5)	N3—C10—C16—N5	157.9 (5)
C1—C2—C3—C4	−178.8 (5)	C11—C10—C16—N5	−22.8 (6)
C1—C2—C3—C8	0.5 (6)	N3—C10—C16—C17	−22.6 (7)
C1A—C2A—C3A—C4A	−177.1 (5)	C11—C10—C16—C17	156.7 (5)
C1A—C2A—C3A—C8A	1.3 (6)	N3A—C10A—C16A—N5A	156.8 (5)
C8—C3—C4—C5	−1.0 (7)	C11A—C10A—C16A—N5A	−23.9 (6)
C2—C3—C4—C5	178.2 (6)	N3A—C10A—C16A—C17A	−23.2 (7)
C8A—C3A—C4A—C5A	0.1 (8)	C11A—C10A—C16A—C17A	156.1 (5)
C2A—C3A—C4A—C5A	178.3 (6)	N5—C16—C17—C18	−0.4 (8)
C3—C4—C5—C6	2.2 (8)	C10—C16—C17—C18	−179.9 (4)
C3A—C4A—C5A—C6A	1.9 (8)	N5A—C16A—C17A—C18A	−0.1 (9)
C4—C5—C6—C7	−1.6 (8)	C10A—C16A—C17A—C18A	179.8 (5)
C4A—C5A—C6A—C7A	−2.6 (9)	C16—C17—C18—C19	−0.2 (8)
C5—C6—C7—C8	−0.2 (7)	C16A—C17A—C18A—C19A	−0.8 (9)
C5A—C6A—C7A—C8A	1.1 (8)	C17—C18—C19—C20	−0.5 (9)
C6—C7—C8—N1	−178.1 (5)	C17A—C18A—C19A—C20A	0.6 (9)
C6—C7—C8—C3	1.4 (7)	C18—C19—C20—N5	1.8 (10)
C4—C3—C8—N1	178.8 (4)	C18A—C19A—C20A—N5A	0.4 (10)
C2—C3—C8—N1	−0.6 (5)	C7—C8—N1—C1	−179.9 (5)
C4—C3—C8—C7	−0.8 (7)	C3—C8—N1—C1	0.6 (5)
C2—C3—C8—C7	179.8 (4)	C2—C1—N1—C8	−0.3 (5)
C6A—C7A—C8A—N1A	−178.9 (5)	C9—C1—N1—C8	−175.2 (4)
C6A—C7A—C8A—C3A	0.9 (7)	C2A—C1A—N1A—C8A	1.6 (5)
C4A—C3A—C8A—N1A	178.3 (4)	C9A—C1A—N1A—C8A	−176.4 (4)
C2A—C3A—C8A—N1A	−0.3 (5)	C7A—C8A—N1A—C1A	179.1 (5)
C4A—C3A—C8A—C7A	−1.5 (7)	C3A—C8A—N1A—C1A	−0.7 (5)
C2A—C3A—C8A—C7A	179.8 (4)	C1—C9—N2—N3	−178.8 (4)
C2—C1—C9—N2	−169.4 (5)	C1A—C9A—N2A—N3A	−179.0 (4)
N1—C1—C9—N2	4.3 (7)	C16—C10—N3—N2	−174.5 (4)
C2A—C1A—C9A—N2A	−171.7 (5)	C11—C10—N3—N2	6.2 (7)
N1A—C1A—C9A—N2A	5.9 (7)	C9—N2—N3—C10	−147.2 (5)
N3—C10—C11—N4	80.6 (6)	C16A—C10A—N3A—N2A	−175.0 (4)
C16—C10—C11—N4	−98.7 (5)	C11A—C10A—N3A—N2A	5.7 (7)
N3—C10—C11—C12	−100.5 (6)	C9A—N2A—N3A—C10A	−147.6 (5)
C16—C10—C11—C12	80.2 (6)	C14—C15—N4—C11	0.6 (8)
N3A—C10A—C11A—N4A	79.2 (6)	C12—C11—N4—C15	−0.4 (7)
C16A—C10A—C11A—N4A	−100.0 (5)	C10—C11—N4—C15	178.5 (4)
N3A—C10A—C11A—C12A	−99.6 (6)	C14A—C15A—N4A—C11A	2.6 (9)
C16A—C10A—C11A—C12A	81.1 (6)	C12A—C11A—N4A—C15A	−3.3 (8)
N4—C11—C12—C13	−1.6 (7)	C10A—C11A—N4A—C15A	177.9 (5)
C10—C11—C12—C13	179.6 (5)	C17—C16—N5—C20	1.6 (8)
N4A—C11A—C12A—C13A	1.6 (8)	C10—C16—N5—C20	−178.9 (4)
C10A—C11A—C12A—C13A	−179.7 (5)	C19—C20—N5—C16	−2.3 (9)
C11—C12—C13—C14	3.3 (8)	C17A—C16A—N5A—C20A	1.2 (8)
C11A—C12A—C13A—C14A	1.0 (8)	C10A—C16A—N5A—C20A	−178.8 (4)
C12—C13—C14—C15	−3.0 (8)	C19A—C20A—N5A—C16A	−1.3 (9)

Poly[[2-({[bis(pyridin-2-yl)methylidene]hydrazin-1-ylidene}methyl)-1H-indole]di-µ-chlorido-cadmium(II)] (pCd2) top

Crystal data top

[CdCl₂(C₂₀H₁₅N₅)]	D_x = 1.584 Mg m⁻³
M_r = 508.67	Cu Kα radiation, λ = 1.54184 Å
Trigonal, R3c:H	Cell parameters from 6284 reflections
a = 34.6379 (7) Å	θ = 9.5–71.0°
c = 18.4784 (3) Å	µ = 10.62 mm⁻¹
V = 19199.9 (8) Å³	T = 293 K
Z = 36	Needle, clear light yellow
F(000) = 9072	0.21 × 0.06 × 0.03 mm

Data collection top

Bruker SMART CCD area detector diffractometer	3651 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.020
phi and ω scans	θ_max = 70.9°, θ_min = 4.4°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −36→42
T_min = 0.487, T_max = 0.727	k = −37→41
13934 measured reflections	l = −20→22
4079 independent reflections

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.022	w = 1/[σ²(F_o²) + (0.0235P)² + 26.2978P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.057	(Δ/σ)_max = 0.003
S = 1.09	Δρ_max = 0.38 e Å⁻³
4079 reflections	Δρ_min = −0.31 e Å⁻³
254 parameters	Extinction correction: SHELXL2016 (Sheldrick, 2015b), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0000025 (7)

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.09400 (9)	0.24472 (8)	0.42912 (14)	0.0454 (6)
C2	0.06504 (10)	0.21722 (9)	0.37752 (15)	0.0533 (7)
H2	0.052534	0.225515	0.340423	0.064*
C3	0.05759 (9)	0.17379 (9)	0.39091 (15)	0.0485 (6)
C4	0.03165 (10)	0.13185 (10)	0.35796 (18)	0.0623 (8)
H4	0.014419	0.128848	0.317469	0.075*
C5	0.03210 (11)	0.09567 (10)	0.38614 (19)	0.0674 (9)
H5	0.014970	0.067905	0.364584	0.081*
C6	0.05778 (11)	0.09964 (10)	0.44659 (19)	0.0660 (8)
H6	0.057510	0.074392	0.464353	0.079*
C7	0.08359 (10)	0.13989 (10)	0.48092 (16)	0.0565 (7)
H7	0.100534	0.142151	0.521426	0.068*
C8	0.08335 (9)	0.17700 (8)	0.45273 (14)	0.0444 (6)
C9	0.10845 (9)	0.29131 (8)	0.43834 (14)	0.0458 (6)
H9	0.097544	0.304495	0.406742	0.055*
C10	0.17982 (7)	0.39155 (8)	0.50038 (12)	0.0350 (5)
C11	0.18337 (7)	0.43616 (8)	0.50310 (12)	0.0362 (5)
C12	0.22394 (9)	0.47533 (9)	0.49885 (16)	0.0529 (7)
H12	0.250248	0.474485	0.494282	0.063*
C13	0.22500 (10)	0.51565 (9)	0.50145 (17)	0.0625 (8)
H13	0.252062	0.542222	0.499212	0.075*
C14	0.18595 (10)	0.51626 (9)	0.50734 (16)	0.0582 (7)
H14	0.185895	0.543066	0.509179	0.070*
C15	0.14660 (9)	0.47596 (9)	0.51048 (15)	0.0487 (6)
H15	0.119955	0.476184	0.514635	0.058*
C16	0.22104 (7)	0.38849 (8)	0.50950 (12)	0.0368 (5)
C17	0.23295 (9)	0.36554 (9)	0.46175 (14)	0.0480 (6)
H17	0.215069	0.350835	0.422090	0.058*
C18	0.27198 (10)	0.36487 (11)	0.47407 (16)	0.0578 (7)
H18	0.280967	0.349941	0.442539	0.069*
C19	0.29716 (9)	0.38652 (11)	0.53336 (16)	0.0587 (8)
H19	0.323451	0.386395	0.542971	0.070*
C20	0.28294 (9)	0.40852 (10)	0.57865 (15)	0.0541 (7)
H20	0.300185	0.422940	0.619039	0.065*
N1	0.10545 (7)	0.22063 (7)	0.47458 (11)	0.0452 (5)
H1	0.123466	0.231180	0.510672	0.054*
N2	0.13572 (6)	0.31548 (6)	0.48820 (11)	0.0410 (5)
N3	0.14077 (6)	0.35823 (6)	0.48902 (10)	0.0373 (4)
N4	0.14507 (6)	0.43697 (6)	0.50783 (10)	0.0386 (4)
N5	0.24575 (7)	0.41024 (7)	0.56764 (11)	0.0432 (5)
Cd1	0.07678 (2)	0.37014 (2)	0.49986 (2)	0.03375 (6)
Cl1	0.02612 (2)	0.28840 (2)	0.52485 (3)	0.04579 (15)
Cl2	0.03104 (2)	0.40899 (2)	0.47715 (3)	0.04509 (14)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0442 (14)	0.0389 (13)	0.0567 (15)	0.0234 (12)	−0.0098 (12)	−0.0045 (11)
C2	0.0572 (17)	0.0483 (15)	0.0599 (16)	0.0304 (14)	−0.0176 (13)	−0.0073 (13)
C3	0.0468 (15)	0.0452 (14)	0.0546 (15)	0.0237 (12)	−0.0067 (12)	−0.0079 (12)
C4	0.0547 (18)	0.0521 (17)	0.0742 (19)	0.0224 (14)	−0.0130 (15)	−0.0161 (15)
C5	0.0594 (19)	0.0410 (16)	0.091 (2)	0.0170 (14)	0.0048 (17)	−0.0122 (15)
C6	0.071 (2)	0.0404 (15)	0.089 (2)	0.0293 (15)	0.0187 (18)	0.0090 (15)
C7	0.0626 (18)	0.0527 (17)	0.0606 (17)	0.0336 (15)	0.0057 (14)	0.0070 (13)
C8	0.0448 (14)	0.0406 (13)	0.0509 (14)	0.0236 (12)	0.0005 (11)	−0.0031 (11)
C9	0.0448 (14)	0.0408 (13)	0.0561 (15)	0.0246 (12)	−0.0064 (12)	−0.0026 (11)
C10	0.0306 (11)	0.0398 (12)	0.0361 (11)	0.0186 (10)	−0.0042 (9)	−0.0022 (9)
C11	0.0319 (11)	0.0350 (12)	0.0383 (12)	0.0142 (10)	−0.0020 (9)	−0.0018 (9)
C12	0.0358 (13)	0.0404 (14)	0.0752 (18)	0.0135 (11)	−0.0020 (12)	0.0019 (13)
C13	0.0495 (17)	0.0356 (14)	0.087 (2)	0.0098 (13)	−0.0072 (15)	−0.0006 (14)
C14	0.0664 (19)	0.0361 (14)	0.0722 (18)	0.0258 (14)	−0.0094 (15)	−0.0083 (13)
C15	0.0480 (15)	0.0425 (14)	0.0612 (16)	0.0267 (12)	−0.0046 (12)	−0.0107 (12)
C16	0.0305 (11)	0.0412 (13)	0.0413 (12)	0.0199 (10)	−0.0027 (9)	−0.0014 (10)
C17	0.0422 (14)	0.0582 (16)	0.0466 (14)	0.0273 (13)	−0.0048 (11)	−0.0121 (12)
C18	0.0544 (17)	0.076 (2)	0.0598 (17)	0.0448 (16)	−0.0005 (14)	−0.0145 (15)
C19	0.0468 (16)	0.083 (2)	0.0652 (18)	0.0464 (16)	−0.0113 (13)	−0.0137 (16)
C20	0.0445 (15)	0.0737 (19)	0.0540 (15)	0.0370 (15)	−0.0159 (12)	−0.0161 (14)
N1	0.0476 (12)	0.0420 (11)	0.0511 (12)	0.0261 (10)	−0.0115 (10)	−0.0079 (9)
N2	0.0355 (10)	0.0347 (10)	0.0559 (12)	0.0199 (9)	−0.0042 (9)	−0.0011 (9)
N3	0.0364 (10)	0.0329 (10)	0.0470 (11)	0.0207 (9)	−0.0049 (8)	−0.0019 (8)
N4	0.0351 (10)	0.0350 (10)	0.0447 (11)	0.0168 (9)	−0.0031 (8)	−0.0054 (8)
N5	0.0358 (11)	0.0544 (13)	0.0453 (11)	0.0270 (10)	−0.0063 (9)	−0.0095 (9)
Cd1	0.02975 (9)	0.03423 (10)	0.03777 (10)	0.01637 (7)	−0.00226 (6)	0.00158 (6)
Cl1	0.0447 (3)	0.0366 (3)	0.0374 (3)	0.0064 (2)	−0.0041 (2)	−0.0020 (2)
Cl2	0.0501 (3)	0.0659 (4)	0.0368 (3)	0.0421 (3)	0.0017 (2)	0.0043 (3)

Geometric parameters (Å, º) top

C1—C2	1.366 (4)	C12—C13	1.379 (4)
C1—N1	1.375 (3)	C13—C14	1.368 (4)
C1—C9	1.441 (3)	C14—C15	1.381 (4)
C2—C3	1.415 (4)	C15—N4	1.326 (3)
C3—C4	1.408 (4)	C16—N5	1.345 (3)
C3—C8	1.419 (4)	C16—C17	1.381 (3)
C4—C5	1.364 (4)	C17—C18	1.383 (4)
C5—C6	1.391 (5)	C18—C19	1.367 (4)
C6—C7	1.378 (4)	C19—C20	1.378 (4)
C7—C8	1.391 (4)	C20—N5	1.335 (3)
C8—N1	1.370 (3)	N2—N3	1.401 (3)
C9—N2	1.285 (3)	N3—Cd1	2.4575 (19)
C10—N3	1.282 (3)	N4—Cd1	2.3450 (19)
C10—C11	1.489 (3)	Cd1—Cl1	2.5181 (6)
C10—C16	1.493 (3)	Cd1—Cl2	2.5746 (6)
C11—N4	1.344 (3)	Cd1—Cl1ⁱ	2.6561 (6)
C11—C12	1.384 (3)	Cd1—Cl2ⁱⁱ	2.6612 (6)

C2—C1—N1	109.7 (2)	C19—C18—C17	118.9 (2)
C2—C1—C9	125.9 (2)	C18—C19—C20	118.9 (2)
N1—C1—C9	124.3 (2)	N5—C20—C19	123.5 (2)
C1—C2—C3	107.4 (2)	C8—N1—C1	108.5 (2)
C4—C3—C2	134.8 (3)	C9—N2—N3	111.0 (2)
C4—C3—C8	118.7 (3)	C10—N3—N2	118.11 (19)
C2—C3—C8	106.5 (2)	C10—N3—Cd1	118.00 (15)
C5—C4—C3	119.2 (3)	N2—N3—Cd1	122.12 (14)
C4—C5—C6	121.1 (3)	C15—N4—C11	119.1 (2)
C7—C6—C5	121.9 (3)	C15—N4—Cd1	120.98 (17)
C6—C7—C8	117.5 (3)	C11—N4—Cd1	119.64 (15)
N1—C8—C7	130.6 (3)	C20—N5—C16	117.1 (2)
N1—C8—C3	107.8 (2)	N4—Cd1—N3	67.76 (6)
C7—C8—C3	121.5 (3)	N4—Cd1—Cl1	152.90 (5)
N2—C9—C1	123.0 (2)	N3—Cd1—Cl1	90.34 (5)
N3—C10—C11	116.3 (2)	N4—Cd1—Cl2	94.30 (5)
N3—C10—C16	124.8 (2)	N3—Cd1—Cl2	156.49 (5)
C11—C10—C16	119.0 (2)	Cl1—Cd1—Cl2	110.65 (2)
N4—C11—C12	120.8 (2)	N4—Cd1—Cl1ⁱ	85.72 (5)
N4—C11—C10	117.0 (2)	N3—Cd1—Cl1ⁱ	102.69 (5)
C12—C11—C10	122.2 (2)	Cl1—Cd1—Cl1ⁱ	83.75 (2)
C13—C12—C11	119.4 (3)	Cl2—Cd1—Cl1ⁱ	90.436 (19)
C14—C13—C12	119.5 (3)	N4—Cd1—Cl2ⁱⁱ	96.11 (5)
C13—C14—C15	118.1 (3)	N3—Cd1—Cl2ⁱⁱ	83.49 (5)
N4—C15—C14	123.0 (3)	Cl1—Cd1—Cl2ⁱⁱ	97.04 (2)
N5—C16—C17	122.9 (2)	Cl2—Cd1—Cl2ⁱⁱ	83.511 (19)
N5—C16—C10	114.4 (2)	Cl1ⁱ—Cd1—Cl2ⁱⁱ	173.78 (2)
C17—C16—C10	122.7 (2)	Cd1—Cl1—Cd1ⁱ	94.281 (19)
C16—C17—C18	118.7 (2)	Cd1—Cl2—Cd1ⁱⁱ	96.248 (19)

Symmetry codes: (i) x−y+1/3, −y+2/3, −z+7/6; (ii) y−1/3, x+1/3, −z+5/6.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N5ⁱ	0.86	2.13	2.987 (3)	179
C9—H9···Cl2ⁱⁱ	0.93	2.71	3.588 (3)	159
C12—H12···N5	0.93	2.54	2.995 (4)	110
C18—H18···Cl2ⁱⁱⁱ	0.93	2.83	3.607 (3)	142
C20—H20···Cl1^iv	0.93	2.78	3.431 (3)	128

Symmetry codes: (i) x−y+1/3, −y+2/3, −z+7/6; (ii) y−1/3, x+1/3, −z+5/6; (iii) −y+2/3, −x+1/3, z−1/6; (iv) x+1/3, x−y+2/3, z+1/6.

Comparison of some bond lengths (Å) of two 2-DPHI molecules in the asymmetric unit top

Bond	Value	Bond	Value	Difference (Å)
N2—N3	1.421 (6)	N2A—N3A	1.393 (5)	0.028
C5—C6	1.387 (8)	C5A—C6A	1.413 (8)	0.026
C13—C14	1.377 (8)	C13A—C14A	1.351 (8)	0.026
C6—C7	1.379 (7)	C6A—C7A	1.355 (8)	0.024

Comparison of some bond angles (°) of two 2-DPHI molecules in the asymmetric unit top

Angle	Value	Angle	Value	Difference (°)
C16—C17—C18	117.9 (5)	C16A—C17A—C18A	119.9 (6)	2.0
N4—C11—C10	114.2 (4)	N4A—C11A—C10A	115.7 (4)	1.5
C11—N4—C15	116.6 (5)	C11A—N4A—C15A	118.1 (5)	1.5
C2—C1—C9	130.5 (5)	C2A—C1A—C9A	128.9 (4)	1.4
C13—C14—C15	117.5 (5)	C13A—C14A—C15A	118.9 (6)	1.4
N2—C9—C1	119.2 (5)	N2A—C9A—C1A	120.6 (4)	1.4
C10—C16—C17	121.2 (5)	C10A—C16A—C17A	122.5 (5)	1.3
N5—C16—C17	123.8 (4)	N5A—C16A—C17A	122.5 (5)	1.3
C6—C7—C8	117.0 (5)	C6A—C7A—C8A	118.2 (5)	1.2
N4—C15—C14	124.8 (6)	N4A—C15A—C14A	123.6 (6)	1.2
C3—C8—C7	122.7 (5)	C3A—C8A—C7A	121.5 (5)	1.2
N1—C8—C7	129.7 (5)	N1A—C8A—C7A	130.8 (5)	1.1
N3—C10—C11	123.4 (4)	N3A—C10A—C11A	122.5 (4)	1.1
C18—C19—C20	119.2 (5)	C18A—C19A—C20A	118.2 (5)	1.0
N1—C1—C9	120.7 (4)	N1A—C1A—C9A	121.7 (4)	1.0
N4—C11—C12	122.9 (5)	N4A—C11A—C12A	121.9 (5)	1.0
N3—N2—C9	113.6 (4)	N3A—N2A—C9A	114.6 (4)	1.0

Hydrogen-bond geometries (Å, °) of 2-DPHI top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N4ⁱ	0.86	2.21	3.042 (6)	162
N1A—H1A···N4Aⁱ	0.86	2.20	3.030 (6)	163

Symmetry code: (i) x-1, y, z.

π–π interaction geometries (Å, °) of 2-DPHI top

d represents the distance between the centroids of the two rings; α is the dihedral angle between the two rings; β is the angle between the line connecting the two centroids and the normal to ring I; γ is the angle between the line connecting the two centroids and the normal to ring J; e denotes the perpendicular distance from the centroid of ring I to ring J; f denotes the perpendicular distance from the centroid of ring J to ring I. Ring definitions: ring 1 N1/C1–C3/C8; ring 2 C3–C8; ring 3: N1A/C1A–C3A/C8A; ring 4: C3A–C8A.

π–π interactions (I→J)	d	α	β	γ	e	f
Cg1→Cg2ⁱ	3.876 (3)	1.27	29.09	29.18	3.384	3.387
Cg2→Cg1ⁱⁱ	3.875 (3)	1.27	29.18	29.09	3.386	3.384
Cg3→Cg4ⁱ	3.886 (3)	1.64	28.42	28.53	3.414	3.418
Cg4→Cg3ⁱⁱ	3.886 (3)	1.64	28.53	28.42	3.418	3.414

Symmetry codes: (i) x+1, y, z; (ii) x-1, y, z.

Characteristic UV absorption peaks of 2-DPHI and the corresponding predicted major orbital transitions top

λ_exp (nm)	λ_cal (nm)	f	MO transitions (configurations)
205.5	219.99	0.3973	H→L+6 (38.9%)
			H-5→L+2 (5.6%)
			H→L+4 (5.4%)
	221.36	0.4692	H-1→L+6 (30.9%)
			H-1→L+5 (25.4%)
			H→L+6 (6.5%)
			H→L+5 (5.0%)
252	242.73	0.2481	H→L+3 (15.6%)
			H→L+1 (10.9%)
			H-2→L+1 (8.2%)
			H→L+2 (6.0%)
			H-3→L+2 (5.8%)
			H-5→L (5.1%)
	249.26	0.36947	H-5 → L (17.0%)
			H → L+2 (14.1%)
			H → L+1 (8.4%)
			H → L+5 (8.0%)
			H-10 → L (7.5%)
366.5	363.80	1.41636	H→L (81.9%)

IC₅₀ (µM) values of the Schiff base complex, its corresponding ligand and the metal salt across four cell lines top

Compound	A375 (95% CI)	A549 (95% CI)	HeLa (95% CI)	HFF-1 (95% CI)
2-DPHI	12.22 (10.98–13.62)	15.17 (13.42–17.19)	>100	>100
pCd2	4.88 (4.43–5.35)	20.16 (19.19–21.18)	5.20 (4.90–5.51)	98.11 (97.89–98.33)
CdCl₂	10.70 (9.47–12.00)	16.55 (15.21–17.94)	3.63 (3.33–3.95)	21.31 (21.02–21.67)
Cisplatin	5.88 (5.42–6.36)	5.05 (4.13–6.18)	5.96 (5.42–6.56)	33.34 (33.04–33.64)

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Text
		Plain Text

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Text
		Plain Text

Search IUCr Journals		doi		Advanced search
Author		volume	page

Synthesis, crystal structures and anti­proliferative activities of a new indole-containing dipyridyl­methanone hydrazone Schiff base and its cadmium(II) com­plex

Supporting information

Synthesis, crystal structures and antiproliferative activities of a new indole-containing dipyridylmethanone hydrazone Schiff base and its cadmium(II) complex