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Structural study of bioisosteric derivatives of 5-(1H-indol-3-yl)-benzotriazole and their ability to form chalcogen bonds

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aNamur Institute of Structured Matter (NISM), Namur Research Institute for Life Science (NARILIS), Department of Chemistry, Laboratoire de Chimie Biologique Structurale (CBS) University of Namur (UNamur), 61 Rue de Bruxelles, 5000, Namur, Belgium, and bLouvain Drug Research Institute (LDRI), Université Catholique de Louvain (UCLouvain), Brussels B-1200, Belgium
*Correspondence e-mail: manon.mirgaux@unamur.be, johan.wouters@unamur.be

Edited by L. Van Meervelt, Katholieke Universiteit Leuven, Belgium (Received 9 March 2022; accepted 16 March 2022; online 22 March 2022)

Recently, inter­est in the isosteric replacement of a nitro­gen atom to selenium, sulfur or oxygen atoms has been highlighted in the design of potential inhibitors for cancer research. In this context, the structures of 5-(1H-indol-3-yl)-2,1,3-benzotriazole derivatives [5-(1H-indol-3-yl)-2,1,3-benzo­thia­diazole (bS, C14H9N3S) and 5-(1H-indol-3-yl)-2,1,3-benzoxa­diazole (bO, C14H9N3O)], as well as a synthesis inter­mediate of the selenated bioisostere [5-[1-(benzensulfon­yl)-1H-indol-3-yl]-2,1,3-benzoselena­diazole (p-bSe, C20H13N3O2SSe)] were determined using single-crystal X-ray diffraction (SCXRD) analyses. Despite being analogues, different crystal packing, torsion angles and supra­molecular features were observed, depending on the substitution of the central atoms of the benzotriazole. In particular, chalcogen inter­actions were described in the case of p-bSe and not in the bS and bO derivatives. An investigation by ab initio computational methods was therefore conducted to understand the effect of the substitution on the ability to form chalcogen bonds and the flexibility of the compounds.

1. Chemical context

Isosteric replacement is a common strategy in drug design to modulate the physicochemical properties of potential inhibitors. In 2021, Kozlova and co-workers (Kozlova et al., 2021a[Kozlova, A., Thabault, L., Dauguet, N., Deskeuvre, M., Stroobant, V., Pilotte, L. & Frédérick, R. (2021a). Eur. J. Med. Chem. 227, 113892. https://doi.org/10.1016/j.ejmech.2021.113892]) highlighted a series of bioisosteric derivatives acting as potential new inhibitors of the protein hTDO2, a therapeutic target in cancer research. These new mol­ecules differ in the replacement of the central atom of benzotriazole by an oxygen, sulfur or selenium atom (Fig. 1[link]). At this time, these inhibitors have not yet been crystallized or structurally characterized. In this context, the present work provides a structural characterization of the inhibitors described by Kozlova et al. (2021b[Kozlova, A., Thabault, L., Liberelle, M., Klaessens, S., Prévost, J. R., Mathieu, C., Pilotte, L., Stroobant, V., Van den Eynde, B. & Frédérick, R. (2021b). J. Med. Chem. 64, 10967-10980.]) completed by ab initio calculations for their conformational characterization.

[Figure 1]
Figure 1
Structures of bioisosteres of 5-(1H-indol-3-yl)-benzotriazole with their torsion angle. X = NH, O, S, Se.

The contribution of an oxygen, a sulfur or a selenium atom instead of a nitro­gen affects the ability of these inhibitors to participate in the formation of chalcogen bonds (Vogel et al., 2019[Vogel, L., Wonner, P. & Huber, S. M. (2019). Angew. Chem. Int. Ed. 58, 1880-1891.]). In particular, in these compounds, oxygen, sulfur and selenium atoms could act as chalcogen-bond donors. In recent years, the importance of chalcogen bonds in the stability and folding of proteins as well as their inter­action with ligands has been highlighted by numerous investigations (Newberry & Raines, 2019[Newberry, R. W. & Raines, R. T. (2019). Chem. Biol. 14, 1677-1686.]; Kříž et al., 2018[Kříž, K., Fanfrlík, J. & Lepšík, M. (2018). ChemPhysChem, 19, 2540-2548.]; Iwaoka et al., 2001[Iwaoka, M., Takemoto, S., Okada, M. & Tomoda, S. (2001). Chem. Lett. 30, 132-133.]; Iwaoka & Babe, 2015[Iwaoka, M. & Babe, N. (2015). Phosphorus Sulfur Silicon, 190, 1257-1264.]; Burling & Goldstein, 1992[Burling, F. T. & Goldstein, B. M. (1992). J. Am. Chem. Soc. 114, 2313-2320.]). In this article, the potential ability of the compounds to inter­act with aromatic groups, by chalcogen–π inter­actions (Aakeroy et al., 2019[Aakeroy, C. B., Bryce, D. L., Desiraju, G. R., Frontera, A., Legon, A. C., Nicotra, F., Rissanen, K., Scheiner, S., Terraneo, G., Metrangolo, P. & Resnati, G. (2019). Pure Appl. Chem. 91, 1889-1892.]), was revealed by the crystallization of 5-[1-(benzensulfon­yl)-1H-indol-3-yl] −2,1,3-benzoselena­diazole. Therefore, the effect of bioisosteric replacement on the ability to form chalcogen bonds has been studied by ab initio calculated electrostatic potential maps. This inter­esting series could be the starting point for the study of the effect of chalcogen inter­action on protein stability and affinity.

[Scheme 1]

2. Structural commentary

The compounds investigated in this study were kindly provided by the team of Raphaël Frédérick (UCLouvain, Belgium). Crystallization assays were performed, by slow evaporation at room temperature (293–298 K), in four different solvents [tetra­hydro­furan (THF), chloro­form, di­chloro­methane and N,N-di­methyl­formamide (DMF)]. Crystals of 5-(1H-indol-3-yl)-2,1,3-benzoxa­diazole (bO) and of 5-(1H-indol-3-yl)-2,1,3-benzo­thia­diazole (bS) were obtained from chloro­form. Despite numerous attempts, we were not able to crystallize the compound 5-(1H-indol-3-yl)-2,1,3-benzoselena­diazole (bSe). However, crystals of a synthesis inter­mediate – 5-[1-(benzensulfon­yl)-1H-indol-3-yl]-2,1,3-benzo­selena­diazole (p-bSe) – were obtained in THF.

5-[1-(Benzensulfon­yl)-1H-indol-3-yl]-2,1,3-benzoselena­dia­zole (p-bSe) crystallized in space group P[\overline{1}] with one mol­ecule of p-bSe in the asymmetric unit [Fig. 2[link](a)]. Inter­estingly, the mol­ecule adopts an almost planar dihedral angle [−168.3 (2)°] between the indole and benzoselena­diazole ring (Fig. 3[link]). 5-(1H-indol-3-yl)-2,1,3-benzo­thia­diazole (bS) and 5-(1H-indol-3-yl)-2,1,3-benzoxa­diazole (bO) crystallized in space group Pbca [Fig. 2[link](b) and (c)]. The asymmetric units contain one mol­ecule of bS or bO without disorder. In the three structures, two mirror images are observed in the crystal packing with a torsion angle of ±168.3 (2)° for p-bSe, ±36.9 (2)° for bS and ±146.7 (2)° for bO between the two aromatic parts of the mol­ecules (Fig. 3[link]). The isosteric replacement does not change significantly the planarity of the benzotriazole ring (r.m.s. deviation from planarity: 0.013 Å for p-bSe, 0.006 Å for bS and bO) or the indole ring (0.010 Å for p-bSe, 0.025 Å for bS and 0.011 Å for bO).

[Figure 2]
Figure 2
Ellipsoid plots with atom labeling for (a) p-bSe (b) bS and (c) bO. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 3]
Figure 3
Two perpendicular views (I. and II.) of the two mirror images observed in the crystal packings for (a) p-bSe (b) bS and (c) bO. Superposition of the mirror images with respect to the indole group. Torsion angles are ±168.3 (2)° for p-bSe, ±36.9 (2)° for bS and ±146.7 (2)° for bO.

3. Supra­molecular features

In the structure of p-bSe, a synthesis inter­mediate of the selenated bioisostere of 5-(1H-indol-3-yl)benzotriazole, the benzene­sulfonyl contributes to the stabilization of the crystal packing through weak hydrogen bonds [Table 1[link], Fig. 4[link](a)] and chalcogen–π inter­actions. π-stacking inter­actions are observed between the selena­diazole and indole groups [centroid (Se/N1/C1/C6/N2)⋯centroid (N3/C7–C10) distance of 3.732 (2) Å, perpendicular distance of 3.587 (1) Å and horizontal displacement of 1.506 Å, Fig. 4[link](b)]. A second π-stacking inter­action is observed between the selena­diazole group (Se/N1/C1/C6/N2) and the indole group (C9–C14) [centroid⋯centroid distance of 3.915 (2) Å, perpendicular distance of 3.646 (1) Å and horizontal displacement of 1.331 Å, Fig. 4[link](b)]. A chalcogen–π inter­action between Se and the benzensulfonyl group (C15–C20) is also involved in crystal-packing stabilization [Se⋯centroid distance of 3.388 (1) Å and N2—Se⋯centroid angle of 159.83 (8)°, Fig. 4[link](b)]. The presence of the protecting group (benzene­sulfon­yl) could explain the crystallization of the p-bSe compound with respect to the bSe compound. Indeed, in p-bSe, the orientation of the protecting group is ideal for allowing a chalcogen–π inter­action whereas this type of inter­actions would be more difficult to set up in bSe.

Table 1
Hydrogen-bond geometry (Å, °) for p-bSe[link]

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H8⋯O2i 0.93 2.46 3.380 (3) 168
C14—H14⋯O1 0.93 2.54 3.099 (4) 119
Symmetry code: (i) [-x+1, -y, -z+1].
[Figure 4]
Figure 4
Supra­molecular organization of p-bSe: (a) hydrogen-bond inter­actions; (b) π-stacking inter­action between the benzoselena­diazole group and the indole groups (centroids in red: Se/N1/C1/C6/N2 and N3/C7–C10 and centroids in green: Se/N1/C1/C6/N2 and C9–C14) as well as chalcogen–π inter­actions (in purple).

In the structure of compound bS, π-inter­actions stabilize the crystal packing. π-stacking is observed between benzo­thia­diazole groups [centroid (C1–C6)⋯centroid (S1/N1/C1/C2/N2) distance of 3.689 (1) Å, perpendicular distance of 3.4989 (7) Å and horizontal displacement of 1.326 Å, Fig. 5[link](a)]. An N—H⋯π inter­action is also observed between indole groups [N3⋯centroid (C9–C14) distance of 3.345 (2) Å, H3N⋯centroid distance of 2.57 (2) Å and N3—H3N⋯centroid angle of 169 (2)°, Fig. 5[link](b)]. In this structure, no chalcogen inter­action involving the sulfur atom is observed.

[Figure 5]
Figure 5
Supra­molecular organization of bS. (a) π-stacking inter­action between the benzo­thia­diazole groups and (b) N—H⋯π inter­action between two indole groups.

The crystal packing of bO is stabilized through π-inter­actions. π-stacking is observed between benzoxa­diazole groups [centroid (O1/N1/C1–C6/N2)⋯centroid (O1/N1/C1–C6/N2) distance of 3.893 (1) Å, perpendicular distance of 3.5469 (8) Å and horizontal displacement of 1.570 Å, Fig. 6[link](a)]. An N—H⋯π inter­action is also observed between indole groups [N3⋯centroid (C9–C14) distance of 3.226 (2) Å, H3N⋯centroid distance of 2.57 (2) Å and N3—H3N⋯centroid angle of 138 (2)°, Fig. 6[link](b)]. No chalcogen inter­action is observed.

[Figure 6]
Figure 6
Supra­molecular organization of bO. (a) π-stacking inter­action between the benzoxa­diazole groups and (b) N—H⋯π inter­action between two indole groups

4. Quantum ab initio studies of the bioisosteric substitution effect

As mentioned previously, the different derivatives vary mainly in their ability to inter­act through chalcogen bonds. In order to characterize these differences in depth, quantum mechanics studies have been conducted. First, the presence of a σ-hole in the electron density was studied by means of electrostatic maps. Analysis indicates that the oxygen in benzoxa­diazole [Fig. 7[link](c)] has a weakly positive environment. The σ-hole formation is enhanced by substitution of the central atom with sulfur [Fig. 7[link](b)] and selenium [Fig. 7[link](a)], with selenium having the most positive environment. The bioisosteric series thus has different characteristics in terms of the ability to form chalcogen bonds, with the selenium compound being the best chaclogen-bond donor in this bioisosteric series of mol­ecules. These results may explain why chalcogen bonds are observed only in the supra­molecular organization of the p-bSe mol­ecule. The donor character of the selenium atom is not affected by the protected group [Fig. 8[link](a) and (b)]. The difficulty in crystallizing bSe (while p-bSe crystallized readily in THF) could be explained by the absence of the protecting group (benzene­sulfon­yl) in bSe. Indeed, the benzene­sulfonyl group in p-bSe is electron-rich and acts as a well-oriented chalcogen-bond acceptor in p-bSe.

[Figure 7]
Figure 7
Computed electrostatic potential (EPS) surfaces and associated mol­ecular structures (a) bSe (b) bS (c) bO. The EPS color scale ranges from +8.160 volt to −5.440 volt.
[Figure 8]
Figure 8
Computed electrostatic potential (EPS) surfaces and associated mol­ecular structures (a) bSe (b) p-bSe. The EPS color scale ranges from +8.160 volts to −5.440 volts.

Secondly, in order to determine the effect of the substitution on the flexibility of the derivatives, conformational scans were performed around the torsion angle formed between the indole ring and the benzo­diazole part (T1). As presented in Fig. 9[link], bO and bS are characterized by a very similar ΔE energy profile associated with the rotation around T1. For all three mol­ecules (bO, bS and bSe), four minima are observed for each mol­ecule, with symmetry on each side of the planar mol­ecule. The energy transitions are low (maximum 15 kJ mol−1) and the mol­ecules are flexible. Moreover, the T1 torsion angles observed in the crystal structures of bS [±36.9 (2)°] and bO [±146.7 (2)°] are consistent with the energy minima determined by ab initio calculations with a relative deviation lower than 10%. Although the bioisosteric character of the flexibility is retained, two differences are observed between the bSe mol­ecule and the bS and bO mol­ecules. The first one is the energy at a torsion angle of 180°, which is lower for the mol­ecule of bSe while it is slightly higher at 0°. The second one is a small shift observed between the angle associated with the energy minima of the bSe mol­ecule and the bS and bO mol­ecules.

[Figure 9]
Figure 9
Conformational scans and associated torsion angles calculated with Gaussian16a (ωB97XD, 6–31+G*).

The same calculations were performed for the protected mol­ecule (p-bSe). The energy profile associated with the rotation around T1 in p-bSe is similar to those determined for bS and bO. There is a small shift of the values of the angle corresponding to the energy minimum with respect to bSe. This shift may be due to the protecting group that causes steric hindrance in p-bSe. The energies corresponding to minima A and C are higher than the energies for minima B and D, involving two local minima and a preference in the conformers. The maxima of the energies between A/B and C/D are also lower than in the case of the other compounds, supporting this hypothesis. In the case of p-bSe, the torsion angle observed in the crystallographic structure [±168.3 (2)°] corresponds to an energy maximum on the energy profile associated with the rotation around T1 determined by ab initio calculations. The quasi-planarity of the mol­ecule observed in the crystallographic structure could be encouraged by the formation of chalcogen bonds stabilizing this conformation of p-bSe.

5. Database survey

The Cambridge Structural Database (CSD version 5.42; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) was searched with ConQuest (version 2021.2.0; Bruno et al., 2002[Bruno, I. J., Cole, J. C., Edgington, P. R., Kessler, M., Macrae, C. F., McCabe, P., Pearson, J. & Taylor, R. (2002). Acta Cryst. B58, 389-397.]) for benzoselena­diazole, benzo­thia­diazole and benzoxa­diazole fragments (Fig. 10[link]). The search for the benzoselena­diazole fragment resulted in 57 hits. Chalcogen bonds are observed in all of these hits. In particular, chalcogen–π inter­actions are observed in four structures [CSD refcodes: QIBQUQ (Lee et al., 2018[Lee, J., Lee, L. M., Arnott, Z., Jenkins, H., Britten, J. F. & Vargas-Baca, I. (2018). New J. Chem. 42, 10555-10562.]), VOPMEV (Lee et al., 2019[Lee, L. M., Corless, V., Luu, H., He, A., Jenkins, H., Britten, J. F., Adam Pani, F. & Vargas-Baca, I. (2019). Dalton Trans. 48, 12541-12548.]), VOPNAS (Lee et al., 2019[Lee, L. M., Corless, V., Luu, H., He, A., Jenkins, H., Britten, J. F., Adam Pani, F. & Vargas-Baca, I. (2019). Dalton Trans. 48, 12541-12548.]), and YIWLOG (Tan et al., 2008[Tan, C. K., Wang, J., Leng, J. D., Zheng, L. L. & Tong, M. L. (2008). Eur. J. Inorg. Chem. pp. 771-778.])], listed in Table 2[link]. The search for a benzo­thia­diazole fragment resulted in 34 hits. Chalcogen bonds but no chalcogen–π inter­actions are observed in these hits. The search for a benzoxa­diazole fragment resulted in 24 hits but no chalcogen inter­actions are observed with the oxygen atom of benzoxa­diazole as a chalcogen donor.

Table 2
Chalcogen bonds (Å, °) observed in benzoselena­diazole fragments in the CSD

CCDC refcode Se label Atoms of the π system Se⋯centroid distance N—Se⋯centroid angle
QIBQUQa Se1 C18–C23 3.3676 (7) 147.08 (4)
QIBQUQa Se1 C12–C17 3.0597 (8) 172.30 (5)
VOPMEVb Se1 C5/C7/C10/C5B/C7B/C10B 3.8142 (3) 163.56 (4)
VOPNASc Se1 C1–C5/C10 3.802 (2) 162.5 (1)
VOPNASc Se2 C1–C5/C10 3.654 (2) 166.5 (1)
YIWLOGd Se5 C10–C15 4.032 (3) 144.6 (2)
YIWLOGd Se6 C34–C39 4.232 (4) 164.3 (4)
Notes: (a) Lee et al. (2018[Lee, J., Lee, L. M., Arnott, Z., Jenkins, H., Britten, J. F. & Vargas-Baca, I. (2018). New J. Chem. 42, 10555-10562.]); (b) Lee et al., 2019[Lee, L. M., Corless, V., Luu, H., He, A., Jenkins, H., Britten, J. F., Adam Pani, F. & Vargas-Baca, I. (2019). Dalton Trans. 48, 12541-12548.]); (c) Lee et al., 2019[Lee, L. M., Corless, V., Luu, H., He, A., Jenkins, H., Britten, J. F., Adam Pani, F. & Vargas-Baca, I. (2019). Dalton Trans. 48, 12541-12548.]); (d) Tan et al. (2008[Tan, C. K., Wang, J., Leng, J. D., Zheng, L. L. & Tong, M. L. (2008). Eur. J. Inorg. Chem. pp. 771-778.]).
[Figure 10]
Figure 10
Fragments searched for in the CSD during the database survey analysis: (a) bSe fragment (b) bS fragment (c) bO fragment.

6. Synthesis and crystallization

The synthesis of the various compounds was reported by Kozlova et al. (2021a[Kozlova, A., Thabault, L., Dauguet, N., Deskeuvre, M., Stroobant, V., Pilotte, L. & Frédérick, R. (2021a). Eur. J. Med. Chem. 227, 113892. https://doi.org/10.1016/j.ejmech.2021.113892]). Crystallization of the 5-(1H-indol-3-yl)-benzotriazole derivatives were carried out by the solvent evaporation method. The compounds were dissolved in THF, chloro­form, di­chloro­methane or DMF until complete dissolution. Slow evaporation of the solvent at room temperature (293–297 K) yielded colorless crystals that were then picked for XRD analysis. Crystals of 5-(1H-indol-3-yl)-2,1,3-benzo­thia­diazole and 5-(1H-indol-3-yl)-2,1,3-benzoxa­diazole were obtained from chloro­form while the protected benzoselena­diazole (5-[1-(benzensulfon­yl)-1H-indol-3-yl]-2,1,3-benzo­sel­ena­diazole) was crystallized in THF.

7. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3[link]. In all of the structures, hydrogen atoms were placed in calculated positions and refined using a riding model [C—H bond length of 0.93 Å, with Uiso(H) = 1.2Ueq(C)]. In the structure of 5-(1H-indol-3-yl)-2,1,3-benzo­thia­diazole, bS, the hydrogen on the nitro­gen atom in the indole group was refined without constraint and the refined N—H distance is 0.78 (2) Å.

Table 3
Experimental details

  p-bSe bS bO
Crystal data
Chemical formula C20H13N3O2SSe C14H9N3S C14H9N3O
Mr 438.35 251.30 235.24
Crystal system, space group Triclinic, P[\overline{1}] Orthorhombic, Pbca Orthorhombic, Pbca
Temperature (K) 295 295 295
a, b, c (Å) 7.7760 (3), 9.9573 (4), 11.4124 (6) 7.5884 (1), 7.1060 (1), 43.2464 (7) 12.0256 (7), 7.7396 (5), 23.8551 (16)
α, β, γ (°) 90.970 (4), 92.771 (4), 94.283 (3) 90, 90, 90 90, 90, 90
V3) 879.95 (7) 2331.98 (6) 2220.3 (2)
Z 2 8 8
Radiation type Cu Kα Cu Kα Cu Kα
μ (mm−1) 4.18 2.32 0.75
Crystal size (mm) 0.19 × 0.10 × 0.01 0.29 × 0.18 × 0.04 0.12 × 0.09 × 0.03
 
Data collection
Diffractometer Xcalibur, Ruby, Gemini ultra Xcalibur, Ruby, Gemini ultra R Xcalibur, Ruby, Gemini ultra
Absorption correction Analytical (CrysAlis PRO; Rigaku OD, 2020[Rigaku OD (2020). CrysAlis PRO. Rigaku Oxford Diffraction Ltd, Yarnton, England.]) Analytical (CrysAlis PRO; Rigaku OD, 2020[Rigaku OD (2020). CrysAlis PRO. Rigaku Oxford Diffraction Ltd, Yarnton, England.]) Analytical (CrysAlis PRO; Rigaku OD, 2020[Rigaku OD (2020). CrysAlis PRO. Rigaku Oxford Diffraction Ltd, Yarnton, England.])
Tmin, Tmax 0.663, 0.958 0.663, 0.920 0.941, 0.981
No. of measured, independent and observed [I > 2σ(I)] reflections 9941, 3113, 2571 10906, 2072, 1825 6883, 1972, 1275
Rint 0.030 0.025 0.047
(sin θ/λ)max−1) 0.598 0.598 0.597
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.101, 1.04 0.035, 0.098, 1.07 0.050, 0.134, 1.06
No. of reflections 3113 2072 1972
No. of parameters 244 167 166
H-atom treatment H-atom parameters constrained 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) 0.46, −0.61 0.20, −0.30 0.14, −0.16
Computer programs: CrysAlis PRO (Rigaku OD, 2020[Rigaku OD (2020). CrysAlis PRO. Rigaku Oxford Diffraction Ltd, Yarnton, England.]), SHELXT2014/5 (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2016/6 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), ShelXle (Hübschle et al., 2011[Hübschle, C. B., Sheldrick, G. M. & Dittrich, B. (2011). J. Appl. Cryst. 44, 1281-1284.]), OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]), andMercury (Macrae et al., 2020[Macrae, C. F., Sovago, I., Cottrell, S. J., Galek, P. T. A., McCabe, P., Pidcock, E., Platings, M., Shields, G. P., Stevens, J. S., Towler, M. & Wood, P. A. (2020). J. Appl. Cryst. 53, 226-235.]).

8. Quantum ab initio methodology

All the mol­ecules investigated in the study (bS, bO, bSe, p-bSe) were optimized starting from the crystal coordinates using the density functional method (DFT) with the exchange-correlation functional ωB97XD and the 6-31+G* basis set. Because we were not able to crystallize the bSe compound, this mol­ecule was created by substitution of the sulfur atom for a selenium atom from the coordinates of the bS mol­ecule. The optimizations were performed with Gaussian16a (Frisch et al., 2016[Frisch, M. J., Trucks, G. W., Schlegel, H. B., Scuseria, G. E., Robb, M. A., Cheeseman, J. R., Scalmani, G., Barone, V., Petersson, G. A., Nakatsuji, H., Li, X., Caricato, M., Marenich, A. V., Bloino, J., Janesko, B. G., Gomperts, R., Mennucci, B., Hratchian, H. P., Ortiz, J. V., Izmaylov, A. F., Sonnenberg, J. L., Williams-Young, D., Ding, F., Lipparini, F., Egidi, F., Goings, J., Peng, B., Petrone, A., Henderson, T., Ranasinghe, D., Zakrzewski, V. G., Gao, J., Rega, N., Zheng, G., Liang, W., Hada, M., Ehara, M., Toyota, K., Fukuda, R., Hasegawa, J., Ishida, M., Nakajima, T., Honda, Y., Kitao, O., Nakai, H., Vreven, T., Throssell, K., Montgomery, J. A. Jr, Peralta, J. E., Ogliaro, F., Bearpark, M. J., Heyd, J. J., Brothers, E. N., Kudin, K. N., Staroverov, V. N., Keith, T. A., Kobayashi, R., Normand, J., Raghavachari, K., Rendell, A. P., Burant, J. C., Iyengar, S. S., Tomasi, J., Cossi, M., Millam, J. M., Klene, M., Adamo, C., Cammi, R., Ochterski, J. W., Martin, R. L., Morokuma, K., Farkas, O., Foresman, J. B. & Fox, D. J. (2016). Gaussian16a. Gaussian, Inc., Wallingford, CT, USA.]) the in gas phase. The electrostatic potential was calculated from the SCF-type density and was sliced by making 80 cubic points evenly distributed on a rectangular grid automatically generated by Gaussian16a. The resulting maps were visualized using DrawMol (Liegeois, 2021[Liegeois, V. (2021). DrawMol. University of Namur, Belgium. www. unamur. be/drawmol]). For the conformational scans, the optimized structures were analyzed using relaxed scans around the torsion angle (T1) formed between the indole ring and the benzo­diazole part from 0 to 360° by steps of 20°. The resulting conformations close to an energy minimum were extracted and refined by a new optimization at the same level of approximation. The preparation of the input files, as well as the visualization of the results was performed with the DrawMol and DrawSpectrum suite of programs (Liegeois, 2021[Liegeois, V. (2021). DrawMol. University of Namur, Belgium. www. unamur. be/drawmol]). The graphs were drawn with the program Prism from GraphPad (one-way ANOVA followed by Dunnetts multiple comparisons test, Prism version 8.0.0 for Windows; GraphPad, 2021[GraphPad (2021). GraphPad. GraphPad Software, San Diego, California USA, www. graphpad. com]).

Supporting information


Computing details top

For all structures, data collection: CrysAlis PRO (Rigaku OD, 2020); cell refinement: CrysAlis PRO (Rigaku OD, 2020); data reduction: CrysAlis PRO (Rigaku OD, 2020); program(s) used to solve structure: SHELXT2014/5 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2016/6 (Sheldrick, 2015b), ShelXle (Hübschle et al., 2011), OLEX2 (Dolomanov et al., 2009); molecular graphics: Mercury (Macrae et al., 2020).

5-[1-(Benzenesulfonyl)-1H-indol-3-yl]-2,1,3-benzoselenadiazole (p-bSe) top
Crystal data top
C20H13N3O2SSeZ = 2
Mr = 438.35F(000) = 440
Triclinic, P1Dx = 1.654 Mg m3
a = 7.7760 (3) ÅCu Kα radiation, λ = 1.54184 Å
b = 9.9573 (4) ÅCell parameters from 4183 reflections
c = 11.4124 (6) Åθ = 3.9–66.7°
α = 90.970 (4)°µ = 4.18 mm1
β = 92.771 (4)°T = 295 K
γ = 94.283 (3)°Plate, colourless
V = 879.95 (7) Å30.19 × 0.10 × 0.01 mm
Data collection top
Xcalibur, Ruby, Gemini ultra
diffractometer
3113 independent reflections
Radiation source: fine-focus sealed X-ray tube, Enhance Ultra (Cu) X-ray Source2571 reflections with I > 2σ(I)
Detector resolution: 5.1856 pixels mm-1Rint = 0.030
ω scansθmax = 67.2°, θmin = 3.9°
Absorption correction: analytical
(CrysAlisPro; Rigaku OD, 2020)
h = 99
Tmin = 0.663, Tmax = 0.958k = 119
9941 measured reflectionsl = 1313
Refinement top
Refinement on F2Primary atom site location: dual
Least-squares matrix: fullSecondary atom site location: dual
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.101H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0588P)2 + 0.2071P]
where P = (Fo2 + 2Fc2)/3
3113 reflections(Δ/σ)max = 0.001
244 parametersΔρmax = 0.46 e Å3
0 restraintsΔρmin = 0.61 e Å3
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. Structures were solved by the dual-space method of ShelXT (Sheldrick, 2015a) within Olex2 (Dolomanov et al., 2009). Structures were refined by the least- squares method implemented in SHELXL (Sheldrick, 2015b) within ShelXle (Hübschle et al., 2011). Structures and crystal packings were visualized using Mercury (Macrae et al., 2020).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Se10.90079 (4)0.81216 (3)0.75959 (3)0.07181 (16)
S10.52981 (9)0.00138 (6)0.25117 (6)0.05354 (19)
O10.4385 (3)0.0082 (2)0.13980 (18)0.0639 (5)
O20.4503 (3)0.0486 (2)0.35371 (18)0.0650 (5)
N10.9080 (3)0.7558 (3)0.6120 (2)0.0674 (7)
N20.7790 (4)0.6657 (3)0.8062 (2)0.0685 (7)
N30.5808 (3)0.1632 (2)0.2811 (2)0.0539 (5)
C10.8223 (3)0.6341 (3)0.6050 (2)0.0529 (6)
C20.7984 (4)0.5541 (3)0.5005 (2)0.0558 (6)
H20.8464440.5852540.4320730.067*
C30.7060 (3)0.4321 (2)0.4993 (2)0.0481 (6)
C40.6317 (4)0.3868 (3)0.6070 (2)0.0570 (7)
H40.5666100.3044960.6061990.068*
C50.6530 (4)0.4592 (3)0.7089 (3)0.0620 (7)
H50.6043490.4263140.7765550.074*
C60.7506 (4)0.5862 (3)0.7115 (2)0.0553 (6)
C70.6741 (3)0.3458 (2)0.3939 (2)0.0477 (6)
C80.6014 (3)0.2176 (3)0.3945 (2)0.0519 (6)
H80.5697090.1721600.4616030.062*
C90.6494 (3)0.2603 (3)0.2037 (2)0.0517 (6)
C100.7064 (3)0.3750 (3)0.2714 (2)0.0503 (6)
C110.7763 (5)0.4873 (3)0.2134 (3)0.0675 (8)
H110.8142690.5658490.2551730.081*
C120.7881 (5)0.4801 (3)0.0936 (3)0.0802 (10)
H120.8343700.5546380.0547120.096*
C130.7326 (5)0.3643 (3)0.0297 (3)0.0730 (9)
H130.7444300.3621730.0509760.088*
C140.6602 (4)0.2520 (3)0.0831 (2)0.0616 (7)
H140.6207020.1745450.0402670.074*
C150.7292 (4)0.0687 (2)0.2387 (2)0.0545 (6)
C160.8268 (4)0.0925 (3)0.3403 (3)0.0637 (7)
H160.7870110.0729950.4137870.076*
C170.9851 (4)0.1459 (3)0.3296 (3)0.0732 (9)
H171.0524700.1629690.3964430.088*
C181.0426 (4)0.1736 (3)0.2205 (3)0.0733 (9)
H181.1495960.2082730.2140870.088*
C190.9442 (5)0.1509 (3)0.1210 (3)0.0723 (8)
H190.9846060.1708010.0477490.087*
C200.7853 (4)0.0986 (3)0.1287 (3)0.0636 (7)
H200.7175470.0838000.0614630.076*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Se10.0753 (2)0.0682 (2)0.0690 (3)0.00422 (16)0.00371 (17)0.02183 (16)
S10.0587 (4)0.0467 (4)0.0525 (4)0.0097 (3)0.0021 (3)0.0040 (3)
O10.0655 (12)0.0654 (12)0.0575 (12)0.0055 (9)0.0107 (9)0.0115 (9)
O20.0722 (12)0.0598 (11)0.0604 (12)0.0146 (9)0.0078 (10)0.0011 (9)
N10.0683 (15)0.0635 (15)0.0673 (16)0.0116 (11)0.0024 (12)0.0126 (12)
N20.0805 (17)0.0695 (16)0.0551 (15)0.0090 (13)0.0007 (13)0.0112 (12)
N30.0681 (14)0.0440 (11)0.0473 (12)0.0086 (9)0.0006 (10)0.0024 (9)
C10.0520 (14)0.0522 (14)0.0534 (16)0.0035 (11)0.0050 (12)0.0072 (11)
C20.0604 (16)0.0571 (15)0.0486 (15)0.0046 (12)0.0043 (12)0.0038 (11)
C30.0519 (14)0.0454 (13)0.0471 (14)0.0061 (10)0.0019 (11)0.0009 (10)
C40.0734 (18)0.0461 (14)0.0511 (16)0.0018 (12)0.0011 (13)0.0019 (11)
C50.081 (2)0.0578 (16)0.0477 (16)0.0068 (14)0.0042 (14)0.0048 (12)
C60.0607 (16)0.0553 (15)0.0501 (15)0.0136 (12)0.0058 (13)0.0059 (12)
C70.0507 (14)0.0481 (13)0.0440 (14)0.0034 (10)0.0012 (11)0.0017 (10)
C80.0604 (15)0.0502 (14)0.0443 (14)0.0010 (11)0.0010 (12)0.0005 (11)
C90.0562 (15)0.0506 (14)0.0477 (15)0.0020 (11)0.0008 (12)0.0019 (11)
C100.0567 (15)0.0463 (14)0.0483 (15)0.0048 (11)0.0041 (12)0.0004 (11)
C110.096 (2)0.0478 (15)0.0566 (18)0.0091 (14)0.0058 (16)0.0007 (12)
C120.120 (3)0.0613 (18)0.0573 (19)0.0120 (18)0.0133 (18)0.0073 (14)
C130.103 (2)0.0705 (19)0.0446 (16)0.0002 (16)0.0070 (16)0.0032 (13)
C140.0788 (19)0.0597 (16)0.0450 (15)0.0000 (14)0.0025 (14)0.0026 (12)
C150.0639 (16)0.0401 (13)0.0568 (16)0.0098 (11)0.0022 (13)0.0009 (11)
C160.0712 (19)0.0583 (16)0.0591 (17)0.0064 (13)0.0054 (14)0.0028 (13)
C170.072 (2)0.0647 (19)0.080 (2)0.0023 (15)0.0186 (17)0.0078 (16)
C180.0690 (19)0.0574 (18)0.093 (3)0.0020 (14)0.0006 (18)0.0007 (16)
C190.082 (2)0.0645 (19)0.071 (2)0.0070 (16)0.0059 (17)0.0070 (15)
C200.0748 (19)0.0565 (16)0.0581 (18)0.0004 (13)0.0013 (15)0.0041 (13)
Geometric parameters (Å, º) top
Se1—N11.772 (3)C8—H80.9300
Se1—N21.782 (3)C9—C141.384 (4)
S1—O11.424 (2)C9—C101.399 (4)
S1—O21.430 (2)C10—C111.398 (4)
S1—N31.657 (2)C11—C121.376 (5)
S1—C151.758 (3)C11—H110.9300
N1—C11.337 (4)C12—C131.383 (5)
N2—C61.329 (4)C12—H120.9300
N3—C81.391 (3)C13—C141.379 (4)
N3—C91.414 (4)C13—H130.9300
C1—C21.420 (4)C14—H140.9300
C1—C61.436 (4)C15—C201.383 (4)
C2—C31.365 (4)C15—C161.388 (4)
C2—H20.9300C16—C171.386 (5)
C3—C41.448 (4)C16—H160.9300
C3—C71.466 (4)C17—C181.374 (5)
C4—C51.355 (4)C17—H170.9300
C4—H40.9300C18—C191.370 (5)
C5—C61.424 (4)C18—H180.9300
C5—H50.9300C19—C201.383 (5)
C7—C81.357 (4)C19—H190.9300
C7—C101.463 (4)C20—H200.9300
N1—Se1—N295.07 (11)C14—C9—C10123.6 (3)
O1—S1—O2120.66 (12)C14—C9—N3129.3 (3)
O1—S1—N3107.53 (12)C10—C9—N3107.1 (2)
O2—S1—N3104.65 (12)C11—C10—C9117.9 (3)
O1—S1—C15108.75 (13)C11—C10—C7134.3 (3)
O2—S1—C15109.34 (13)C9—C10—C7107.8 (2)
N3—S1—C15104.72 (12)C12—C11—C10119.0 (3)
C1—N1—Se1106.3 (2)C12—C11—H11120.5
C6—N2—Se1105.8 (2)C10—C11—H11120.5
C8—N3—C9108.0 (2)C11—C12—C13121.5 (3)
C8—N3—S1123.64 (18)C11—C12—H12119.3
C9—N3—S1126.7 (2)C13—C12—H12119.3
N1—C1—C2124.0 (3)C14—C13—C12121.4 (3)
N1—C1—C6116.0 (3)C14—C13—H13119.3
C2—C1—C6120.0 (2)C12—C13—H13119.3
C3—C2—C1120.8 (3)C13—C14—C9116.6 (3)
C3—C2—H2119.6C13—C14—H14121.7
C1—C2—H2119.6C9—C14—H14121.7
C2—C3—C4118.3 (2)C20—C15—C16121.6 (3)
C2—C3—C7123.5 (2)C20—C15—S1119.6 (2)
C4—C3—C7118.2 (2)C16—C15—S1118.8 (2)
C5—C4—C3122.8 (3)C17—C16—C15118.4 (3)
C5—C4—H4118.6C17—C16—H16120.8
C3—C4—H4118.6C15—C16—H16120.8
C4—C5—C6119.4 (3)C18—C17—C16120.2 (3)
C4—C5—H5120.3C18—C17—H17119.9
C6—C5—H5120.3C16—C17—H17119.9
N2—C6—C5124.5 (3)C19—C18—C17120.8 (3)
N2—C6—C1116.8 (3)C19—C18—H18119.6
C5—C6—C1118.7 (2)C17—C18—H18119.6
C8—C7—C10106.2 (2)C18—C19—C20120.4 (3)
C8—C7—C3123.9 (2)C18—C19—H19119.8
C10—C7—C3129.8 (2)C20—C19—H19119.8
C7—C8—N3110.8 (2)C19—C20—C15118.6 (3)
C7—C8—H8124.6C19—C20—H20120.7
N3—C8—H8124.6C15—C20—H20120.7
N2—Se1—N1—C10.2 (2)C8—N3—C9—C14179.1 (3)
N1—Se1—N2—C60.4 (2)S1—N3—C9—C1413.3 (4)
O1—S1—N3—C8151.5 (2)C8—N3—C9—C101.8 (3)
O2—S1—N3—C822.0 (3)S1—N3—C9—C10167.7 (2)
C15—S1—N3—C893.0 (2)C14—C9—C10—C110.7 (4)
O1—S1—N3—C944.8 (3)N3—C9—C10—C11178.4 (3)
O2—S1—N3—C9174.2 (2)C14—C9—C10—C7179.9 (3)
C15—S1—N3—C970.8 (3)N3—C9—C10—C71.0 (3)
Se1—N1—C1—C2180.0 (2)C8—C7—C10—C11179.5 (3)
Se1—N1—C1—C60.7 (3)C3—C7—C10—C110.8 (5)
N1—C1—C2—C3178.5 (3)C8—C7—C10—C90.3 (3)
C6—C1—C2—C30.8 (4)C3—C7—C10—C9178.5 (3)
C1—C2—C3—C40.5 (4)C9—C10—C11—C120.8 (5)
C1—C2—C3—C7178.9 (2)C7—C10—C11—C12180.0 (3)
C2—C3—C4—C51.3 (4)C10—C11—C12—C130.1 (6)
C7—C3—C4—C5179.8 (3)C11—C12—C13—C141.2 (6)
C3—C4—C5—C60.7 (4)C12—C13—C14—C91.3 (5)
Se1—N2—C6—C5178.2 (2)C10—C9—C14—C130.3 (5)
Se1—N2—C6—C10.9 (3)N3—C9—C14—C13179.3 (3)
C4—C5—C6—N2179.7 (3)O1—S1—C15—C2011.5 (3)
C4—C5—C6—C10.6 (4)O2—S1—C15—C20145.2 (2)
N1—C1—C6—N21.2 (4)N3—S1—C15—C20103.2 (2)
C2—C1—C6—N2179.5 (3)O1—S1—C15—C16168.6 (2)
N1—C1—C6—C5178.0 (3)O2—S1—C15—C1635.0 (2)
C2—C1—C6—C51.4 (4)N3—S1—C15—C1676.7 (2)
C2—C3—C7—C8171.4 (3)C20—C15—C16—C170.8 (4)
C4—C3—C7—C810.2 (4)S1—C15—C16—C17179.0 (2)
C2—C3—C7—C1010.1 (4)C15—C16—C17—C180.3 (4)
C4—C3—C7—C10168.3 (3)C16—C17—C18—C190.9 (5)
C10—C7—C8—N31.4 (3)C17—C18—C19—C200.4 (5)
C3—C7—C8—N3177.4 (2)C18—C19—C20—C150.6 (5)
C9—N3—C8—C72.1 (3)C16—C15—C20—C191.3 (4)
S1—N3—C8—C7168.4 (2)S1—C15—C20—C19178.6 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O2i0.932.463.380 (3)168
C14—H14···O10.932.543.099 (4)119
Symmetry code: (i) x+1, y, z+1.
5-[1-(Benzenesulfonyl)-1H-indol-3-yl]-2,1,3-benzothiadiazole (bS) top
Crystal data top
C14H9N3SDx = 1.432 Mg m3
Mr = 251.30Cu Kα radiation, λ = 1.54184 Å
Orthorhombic, PbcaCell parameters from 4620 reflections
a = 7.5884 (1) Åθ = 4.1–67.1°
b = 7.1060 (1) ŵ = 2.32 mm1
c = 43.2464 (7) ÅT = 295 K
V = 2331.98 (6) Å3Plate, colourless
Z = 80.29 × 0.18 × 0.04 mm
F(000) = 1040
Data collection top
Xcalibur, Ruby, Gemini ultra R
diffractometer
2072 independent reflections
Radiation source: fine-focus sealed tube1825 reflections with I > 2σ(I)
Detector resolution: 5.1856 pixels mm-1Rint = 0.025
ω scansθmax = 67.2°, θmin = 4.1°
Absorption correction: analytical
(CrysAlisPro; Rigaku OD, 2020)
h = 98
Tmin = 0.663, Tmax = 0.920k = 87
10906 measured reflectionsl = 5149
Refinement top
Refinement on F2Primary atom site location: dual
Least-squares matrix: fullSecondary atom site location: dual
R[F2 > 2σ(F2)] = 0.035Hydrogen site location: mixed
wR(F2) = 0.098H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.0478P)2 + 0.7413P]
where P = (Fo2 + 2Fc2)/3
2072 reflections(Δ/σ)max = 0.001
167 parametersΔρmax = 0.20 e Å3
0 restraintsΔρmin = 0.30 e Å3
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. Structures were solved by the dual-space method of ShelXT (Sheldrick, 2015a) within Olex2 (Dolomanov et al., 2009). Structures were refined by the least- squares method implemented in SHELXL (Sheldrick, 2015b) within ShelXle (Hübschle et al., 2011). Structures and crystal packings were visualized using Mercury (Macrae et al., 2020).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
S11.08880 (6)0.65005 (9)0.46249 (2)0.0684 (2)
N11.05463 (19)0.6759 (2)0.42591 (3)0.0539 (4)
N30.2880 (2)0.8454 (2)0.33487 (4)0.0567 (4)
H3N0.206 (3)0.904 (3)0.3295 (5)0.065 (6)*
C90.5346 (2)0.6723 (2)0.33531 (4)0.0369 (3)
C50.6078 (2)0.7131 (2)0.39422 (3)0.0384 (4)
C60.7877 (2)0.7053 (2)0.39392 (3)0.0396 (4)
H60.8493250.7148860.3754000.048*
C70.5027 (2)0.7429 (2)0.36611 (4)0.0395 (4)
N20.8896 (2)0.6472 (3)0.47547 (4)0.0649 (5)
C140.6590 (2)0.5510 (2)0.32215 (4)0.0453 (4)
H140.7506830.5028730.3340310.054*
C100.3973 (2)0.7415 (2)0.31639 (4)0.0441 (4)
C10.8784 (2)0.6826 (2)0.42215 (4)0.0415 (4)
C40.5157 (2)0.6949 (3)0.42314 (4)0.0480 (4)
H40.3931930.6989550.4229640.058*
C20.7846 (2)0.6662 (3)0.45063 (4)0.0476 (4)
C30.5985 (2)0.6722 (3)0.45054 (4)0.0543 (5)
H30.5348670.6609720.4688200.065*
C130.6439 (3)0.5037 (3)0.29140 (4)0.0567 (5)
H130.7257490.4222480.2826230.068*
C110.3836 (3)0.6946 (3)0.28513 (4)0.0547 (5)
H110.2930960.7422880.2729360.066*
C80.3506 (2)0.8457 (3)0.36445 (4)0.0518 (4)
H80.2976980.9068610.3810370.062*
C120.5077 (3)0.5761 (3)0.27307 (4)0.0594 (5)
H120.5014920.5428370.2523020.071*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0416 (3)0.1158 (5)0.0479 (3)0.0007 (3)0.00962 (19)0.0036 (3)
N10.0354 (7)0.0777 (11)0.0486 (8)0.0024 (7)0.0023 (6)0.0024 (7)
N30.0500 (9)0.0557 (9)0.0645 (10)0.0187 (8)0.0130 (7)0.0043 (7)
C90.0349 (8)0.0340 (7)0.0417 (8)0.0034 (6)0.0024 (6)0.0053 (6)
C50.0371 (8)0.0380 (8)0.0399 (8)0.0005 (6)0.0003 (6)0.0026 (6)
C60.0363 (8)0.0460 (9)0.0365 (8)0.0000 (7)0.0031 (6)0.0003 (6)
C70.0363 (8)0.0375 (8)0.0448 (8)0.0013 (7)0.0009 (6)0.0014 (7)
N20.0484 (9)0.1062 (14)0.0401 (8)0.0008 (9)0.0042 (7)0.0029 (8)
C140.0431 (9)0.0462 (9)0.0466 (9)0.0039 (7)0.0008 (7)0.0019 (7)
C100.0456 (9)0.0373 (8)0.0494 (9)0.0009 (7)0.0065 (7)0.0082 (7)
C10.0336 (8)0.0490 (9)0.0421 (8)0.0013 (7)0.0012 (6)0.0035 (7)
C40.0323 (8)0.0651 (11)0.0465 (9)0.0003 (8)0.0048 (7)0.0020 (8)
C20.0423 (9)0.0634 (11)0.0370 (8)0.0001 (8)0.0005 (7)0.0032 (7)
C30.0424 (10)0.0812 (13)0.0393 (9)0.0010 (9)0.0090 (7)0.0006 (8)
C130.0638 (12)0.0558 (11)0.0504 (10)0.0032 (9)0.0050 (9)0.0068 (8)
C110.0603 (11)0.0553 (10)0.0486 (10)0.0060 (9)0.0165 (8)0.0119 (8)
C80.0473 (10)0.0537 (10)0.0543 (10)0.0137 (8)0.0026 (8)0.0043 (8)
C120.0739 (13)0.0635 (12)0.0409 (9)0.0103 (11)0.0051 (9)0.0008 (8)
Geometric parameters (Å, º) top
S1—N21.6128 (17)N2—C21.344 (2)
S1—N11.6136 (16)C14—C131.376 (2)
N1—C11.348 (2)C14—H140.9300
N3—C81.365 (2)C10—C111.396 (2)
N3—C101.368 (2)C1—C21.428 (2)
N3—H3N0.79 (2)C4—C31.351 (2)
C9—C141.399 (2)C4—H40.9300
C9—C101.413 (2)C2—C31.413 (3)
C9—C71.444 (2)C3—H30.9300
C5—C61.367 (2)C13—C121.400 (3)
C5—C41.438 (2)C13—H130.9300
C5—C71.469 (2)C11—C121.366 (3)
C6—C11.411 (2)C11—H110.9300
C6—H60.9300C8—H80.9300
C7—C81.368 (2)C12—H120.9300
N2—S1—N1101.07 (8)N1—C1—C6126.36 (15)
C1—N1—S1106.37 (12)N1—C1—C2112.81 (15)
C8—N3—C10109.73 (15)C6—C1—C2120.82 (15)
C8—N3—H3N123.5 (16)C3—C4—C5123.18 (16)
C10—N3—H3N126.6 (16)C3—C4—H4118.4
C14—C9—C10118.42 (15)C5—C4—H4118.4
C14—C9—C7134.62 (15)N2—C2—C3126.70 (17)
C10—C9—C7106.86 (14)N2—C2—C1113.72 (16)
C6—C5—C4119.35 (15)C3—C2—C1119.58 (15)
C6—C5—C7122.68 (14)C4—C3—C2118.11 (16)
C4—C5—C7117.97 (14)C4—C3—H3120.9
C5—C6—C1118.95 (14)C2—C3—H3120.9
C5—C6—H6120.5C14—C13—C12121.24 (18)
C1—C6—H6120.5C14—C13—H13119.4
C8—C7—C9106.16 (14)C12—C13—H13119.4
C8—C7—C5125.33 (15)C12—C11—C10117.74 (17)
C9—C7—C5128.51 (14)C12—C11—H11121.1
C2—N2—S1106.03 (13)C10—C11—H11121.1
C13—C14—C9119.16 (16)N3—C8—C7110.01 (16)
C13—C14—H14120.4N3—C8—H8125.0
C9—C14—H14120.4C7—C8—H8125.0
N3—C10—C11130.51 (16)C11—C12—C13121.26 (17)
N3—C10—C9107.23 (15)C11—C12—H12119.4
C11—C10—C9122.17 (16)C13—C12—H12119.4
N2—S1—N1—C10.35 (15)C5—C6—C1—N1178.66 (17)
C4—C5—C6—C11.0 (2)C5—C6—C1—C20.5 (2)
C7—C5—C6—C1177.87 (14)C6—C5—C4—C30.8 (3)
C14—C9—C7—C8175.18 (18)C7—C5—C4—C3178.16 (17)
C10—C9—C7—C80.92 (18)S1—N2—C2—C3179.70 (18)
C14—C9—C7—C54.5 (3)S1—N2—C2—C10.2 (2)
C10—C9—C7—C5179.43 (15)N1—C1—C2—N20.1 (2)
C6—C5—C7—C8143.47 (18)C6—C1—C2—N2179.37 (16)
C4—C5—C7—C835.4 (2)N1—C1—C2—C3179.49 (18)
C6—C5—C7—C936.9 (3)C6—C1—C2—C30.2 (3)
C4—C5—C7—C9144.19 (17)C5—C4—C3—C20.0 (3)
N1—S1—N2—C20.31 (16)N2—C2—C3—C4179.05 (19)
C10—C9—C14—C130.2 (2)C1—C2—C3—C40.4 (3)
C7—C9—C14—C13175.93 (18)C9—C14—C13—C120.6 (3)
C8—N3—C10—C11176.87 (18)N3—C10—C11—C12175.41 (19)
C8—N3—C10—C90.3 (2)C9—C10—C11—C120.7 (3)
C14—C9—C10—N3176.06 (14)C10—N3—C8—C70.3 (2)
C7—C9—C10—N30.78 (18)C9—C7—C8—N30.7 (2)
C14—C9—C10—C110.8 (2)C5—C7—C8—N3179.60 (15)
C7—C9—C10—C11177.65 (15)C10—C11—C12—C130.1 (3)
S1—N1—C1—C6179.53 (14)C14—C13—C12—C110.7 (3)
S1—N1—C1—C20.27 (19)
5-(1H-Indol-3-yl)-2,1,3-benzoxadiazole (bO) top
Crystal data top
C14H9N3ODx = 1.407 Mg m3
Mr = 235.24Cu Kα radiation, λ = 1.54184 Å
Orthorhombic, PbcaCell parameters from 1395 reflections
a = 12.0256 (7) Åθ = 7.4–66.3°
b = 7.7396 (5) ŵ = 0.75 mm1
c = 23.8551 (16) ÅT = 295 K
V = 2220.3 (2) Å3Plate, clear yellow
Z = 80.12 × 0.09 × 0.03 mm
F(000) = 976
Data collection top
Xcalibur, Ruby, Gemini ultra
diffractometer
1972 independent reflections
Radiation source: fine-focus sealed X-ray tube, Enhance Ultra (Cu) X-ray Source1275 reflections with I > 2σ(I)
Detector resolution: 5.1856 pixels mm-1Rint = 0.047
ω scansθmax = 67.1°, θmin = 3.7°
Absorption correction: analytical
(CrysAlisPro; Rigaku OD, 2020)
h = 1412
Tmin = 0.941, Tmax = 0.981k = 69
6883 measured reflectionsl = 2819
Refinement top
Refinement on F2Primary atom site location: dual
Least-squares matrix: fullSecondary atom site location: dual
R[F2 > 2σ(F2)] = 0.050Hydrogen site location: mixed
wR(F2) = 0.134H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0633P)2 + 0.0873P]
where P = (Fo2 + 2Fc2)/3
1972 reflections(Δ/σ)max < 0.001
166 parametersΔρmax = 0.14 e Å3
0 restraintsΔρmin = 0.16 e Å3
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. Structures were solved by the dual-space method of ShelXT (Sheldrick, 2015a) within Olex2 (Dolomanov et al., 2009). Structures were refined by the least- squares method implemented in SHELXL (Sheldrick, 2015b) within ShelXle (Hübschle et al., 2011). Structures and crystal packings were visualized using Mercury (Macrae et al., 2020).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.26211 (19)0.2142 (3)0.43917 (8)0.0909 (6)
N10.1692 (2)0.2567 (3)0.46968 (9)0.0801 (7)
N20.3589 (2)0.2507 (3)0.46824 (9)0.0822 (7)
N30.52478 (16)0.6406 (3)0.70573 (9)0.0640 (6)
H3N0.581 (2)0.696 (3)0.7137 (11)0.077*
C10.2075 (2)0.3199 (3)0.51701 (10)0.0629 (6)
C20.3259 (2)0.3161 (3)0.51611 (10)0.0616 (6)
C30.3883 (2)0.3735 (3)0.56268 (10)0.0610 (6)
H3A0.4655970.3689560.5622240.073*
C40.33330 (18)0.4356 (3)0.60815 (9)0.0520 (6)
C50.21290 (18)0.4396 (3)0.60788 (10)0.0566 (6)
H50.1765490.4822530.6393920.068*
C60.1509 (2)0.3849 (3)0.56443 (10)0.0658 (7)
H60.0736750.3896430.5655670.079*
C70.39274 (17)0.5038 (3)0.65679 (9)0.0506 (5)
C80.49217 (18)0.5924 (3)0.65382 (10)0.0610 (6)
H80.5309900.6156150.6209520.073*
C90.36413 (16)0.4987 (2)0.71516 (9)0.0473 (5)
C100.44927 (17)0.5855 (3)0.74484 (10)0.0513 (6)
C110.4497 (2)0.6039 (3)0.80242 (11)0.0624 (6)
H110.5064330.6633930.8205820.075*
C120.3635 (2)0.5313 (3)0.83195 (11)0.0654 (7)
H120.3619330.5412080.8707910.078*
C130.27815 (19)0.4427 (3)0.80449 (11)0.0606 (6)
H130.2208220.3945000.8254680.073*
C140.27709 (17)0.4252 (3)0.74691 (10)0.0527 (5)
H140.2197350.3657980.7292460.063*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.1045 (15)0.1109 (16)0.0571 (10)0.0033 (12)0.0023 (11)0.0055 (10)
N10.0843 (15)0.0991 (17)0.0569 (14)0.0107 (13)0.0056 (13)0.0038 (12)
N20.0843 (16)0.1040 (17)0.0582 (14)0.0035 (13)0.0010 (12)0.0021 (12)
N30.0455 (10)0.0674 (13)0.0791 (15)0.0127 (9)0.0027 (10)0.0060 (11)
C10.0670 (15)0.0709 (15)0.0507 (15)0.0074 (12)0.0041 (12)0.0099 (12)
C20.0682 (15)0.0693 (15)0.0473 (14)0.0029 (12)0.0075 (12)0.0066 (12)
C30.0510 (13)0.0737 (15)0.0585 (15)0.0027 (12)0.0037 (12)0.0057 (12)
C40.0474 (11)0.0533 (12)0.0552 (13)0.0006 (10)0.0027 (11)0.0089 (11)
C50.0466 (12)0.0683 (14)0.0547 (14)0.0018 (11)0.0013 (11)0.0035 (11)
C60.0506 (13)0.0811 (17)0.0655 (16)0.0038 (12)0.0020 (12)0.0079 (13)
C70.0437 (11)0.0512 (11)0.0570 (14)0.0000 (10)0.0030 (10)0.0048 (11)
C80.0485 (12)0.0708 (14)0.0636 (15)0.0056 (11)0.0031 (11)0.0118 (12)
C90.0414 (10)0.0439 (10)0.0567 (13)0.0029 (9)0.0002 (10)0.0028 (10)
C100.0440 (11)0.0474 (12)0.0626 (15)0.0012 (10)0.0038 (11)0.0010 (11)
C110.0602 (14)0.0566 (13)0.0704 (16)0.0025 (12)0.0105 (13)0.0099 (12)
C120.0720 (16)0.0630 (15)0.0613 (15)0.0119 (13)0.0023 (13)0.0066 (12)
C130.0551 (13)0.0618 (14)0.0648 (15)0.0076 (11)0.0122 (12)0.0040 (12)
C140.0424 (11)0.0514 (12)0.0642 (14)0.0018 (10)0.0023 (11)0.0031 (11)
Geometric parameters (Å, º) top
O1—N11.373 (3)C5—H50.9300
O1—N21.384 (3)C6—H60.9300
N1—C11.314 (3)C7—C81.380 (3)
N2—C21.310 (3)C7—C91.435 (3)
N3—C81.351 (3)C8—H80.9300
N3—C101.370 (3)C9—C141.411 (3)
N3—H3N0.83 (3)C9—C101.415 (3)
C1—C61.413 (3)C10—C111.381 (3)
C1—C21.424 (4)C11—C121.374 (3)
C2—C31.413 (3)C11—H110.9300
C3—C41.358 (3)C12—C131.397 (4)
C3—H3A0.9300C12—H120.9300
C4—C51.448 (3)C13—C141.380 (3)
C4—C71.461 (3)C13—H130.9300
C5—C61.345 (3)C14—H140.9300
N1—O1—N2111.69 (18)C8—C7—C9105.7 (2)
C1—N1—O1105.1 (2)C8—C7—C4124.2 (2)
C2—N2—O1105.1 (2)C9—C7—C4130.03 (19)
C8—N3—C10110.23 (19)N3—C8—C7110.0 (2)
C8—N3—H3N126.4 (19)N3—C8—H8125.0
C10—N3—H3N123.3 (19)C7—C8—H8125.0
N1—C1—C6130.7 (2)C14—C9—C10117.4 (2)
N1—C1—C2109.2 (2)C14—C9—C7135.2 (2)
C6—C1—C2120.1 (2)C10—C9—C7107.39 (18)
N2—C2—C3130.2 (2)N3—C10—C11130.0 (2)
N2—C2—C1108.9 (2)N3—C10—C9106.7 (2)
C3—C2—C1120.8 (2)C11—C10—C9123.3 (2)
C4—C3—C2118.7 (2)C12—C11—C10117.7 (2)
C4—C3—H3A120.6C12—C11—H11121.1
C2—C3—H3A120.6C10—C11—H11121.1
C3—C4—C5119.4 (2)C11—C12—C13121.0 (2)
C3—C4—C7121.6 (2)C11—C12—H12119.5
C5—C4—C7119.0 (2)C13—C12—H12119.5
C6—C5—C4123.4 (2)C14—C13—C12121.4 (2)
C6—C5—H5118.3C14—C13—H13119.3
C4—C5—H5118.3C12—C13—H13119.3
C5—C6—C1117.5 (2)C13—C14—C9119.2 (2)
C5—C6—H6121.2C13—C14—H14120.4
C1—C6—H6121.2C9—C14—H14120.4
N2—O1—N1—C10.4 (3)C5—C4—C7—C935.3 (3)
N1—O1—N2—C20.4 (3)C10—N3—C8—C70.3 (3)
O1—N1—C1—C6179.9 (3)C9—C7—C8—N30.1 (2)
O1—N1—C1—C20.3 (3)C4—C7—C8—N3179.06 (19)
O1—N2—C2—C3178.7 (2)C8—C7—C9—C14177.6 (2)
O1—N2—C2—C10.2 (3)C4—C7—C9—C143.3 (4)
N1—C1—C2—N20.0 (3)C8—C7—C9—C100.1 (2)
C6—C1—C2—N2179.9 (2)C4—C7—C9—C10179.2 (2)
N1—C1—C2—C3178.6 (2)C8—N3—C10—C11179.1 (2)
C6—C1—C2—C31.2 (3)C8—N3—C10—C90.4 (2)
N2—C2—C3—C4179.5 (3)C14—C9—C10—N3178.34 (18)
C1—C2—C3—C41.1 (3)C7—C9—C10—N30.3 (2)
C2—C3—C4—C50.6 (3)C14—C9—C10—C111.2 (3)
C2—C3—C4—C7177.4 (2)C7—C9—C10—C11179.3 (2)
C3—C4—C5—C60.1 (3)N3—C10—C11—C12178.4 (2)
C7—C4—C5—C6177.9 (2)C9—C10—C11—C121.0 (3)
C4—C5—C6—C10.2 (3)C10—C11—C12—C130.3 (3)
N1—C1—C6—C5179.0 (3)C11—C12—C13—C140.1 (3)
C2—C1—C6—C50.8 (3)C12—C13—C14—C90.1 (3)
C3—C4—C7—C834.3 (3)C10—C9—C14—C130.7 (3)
C5—C4—C7—C8143.6 (2)C7—C9—C14—C13178.0 (2)
C3—C4—C7—C9146.7 (2)
Chalcogen bonds (Å, °) observed in benzoselenadiazole fragments in the CSD top
CCDC refcodeSe labelAtoms of the π systemSe···centroid distanceN—Se···centroid angle
QIBQUQaSe1C18–C233.3676 (7)147.08 (4)
QIBQUQaSe1C12–C173.0597 (8)172.30 (5)
VOPMEVbSe1C5/C7/C10/C5B/C7B/C10B3.8142 (3)163.56 (4)
VOPNAScSe1C1–C5/C103.802 (2)162.5 (1)
VOPNAScSe2C1–C5/C103.654 (2)166.5 (1)
YIWLOGdSe5C10–C154.032 (3)144.6 (2)
YIWLOGdSe6C34–C394.232 (4)164.3 (4)
Notes: (a) Lee et al. (2018); (b) Lee et al., 2019); (c) Lee et al., 2019); (d) Tan et al. (2008).
 

Funding information

This research used resources of the `Plateforme Technologique de Calcul Intensif (PTCI)' (https://www.ptci.unamur.be), located at the University of Namur, Belgium, which is supported by the FNRS–FRFC, the Walloon Region, and the University of Namur (Conventions Nos. 2.5020.11, GEQU·G006.15, 1610468, and RW/GEQ2016). The PTCI is a member of the `Consortium des Equipements de Calcul Intensif (CÉCI)` (https://www.ceci-hpc.be). This work is supported by the Belgian Fonds National de la Recherche Scientifique (FRS–FNRS; grant Nos. 3.05557.43, 28252254 and 32704190), the French Community of Belgium (ARC 21/26–115), the Fonds spéciaux de recherche (FSR) at UCLouvain, and a J. Maisin Foundation grant. AK and MM acknowledge the Fonds de la Recherche Scientifique (FRS–FNRS, Belgium) for their Research Fellow grants.

References

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