Facile Access to 2-Selenoxo-1,2,3,4-tetrahydro-4-quinazolinone Scaffolds and Corresponding Diselenides via Cyclization between Methyl Anthranilate and Isoselenocyanates: Synthesis and Structural Features

A practical method for the synthesis of 2-selenoxo-1,2,3,4-tetrahydro-4-quinazolinone was reported. The latter compounds were found to undergo facile oxidation with H2O2 into corresponding diselenides. Novel organoselenium derivatives were characterized by the 1H, 77Se, and 13C NMR spectroscopies, high-resolution electrospray ionization mass spectrometry, IR, elemental analyses (C, H, N), and X-ray diffraction analysis for several of them. Novel heterocycles exhibited multiple remarkable chalcogen bonding (ChB) interactions in the solid state, which were studied theoretically.

There are several approaches to the synthesis of heterocyclic thiones and selones described in the literature. The first one includes halogen to sulfur or selenium substitution employing hydrosulphide or hydroselenide or thio-or selenourea [16][17][18][19]. The Se atom can also be conveniently introduced via substitution of the SMe moiety on treatment with NaSeH [20]. Another widely spread approach to the synthesis of sulfurcontaining derivatives of quinazolinones involves the reaction between o-aminonitriles or o-aminocarboxylates and isothiocyanates or thiourea. However, this approach has been NaSeH [20]. Another widely spread approach to the synthesis of sulfur-containin atives of quinazolinones involves the reaction between o-aminonitriles or o-amino ylates and isothiocyanates or thiourea. However, this approach has been studied the preparation of derivatives of quinazolin-2(1Н)-selones, which is probably du lower stability and synthetic availability of isoselenocyanates [21,22]. It should b that interest in chacogen-containing derivatives of quinazolinones arises due to t tential applications in supramolecular chemistry. Halogen and chalcogen bondin is an area of increasing interest, and these weak interactions are often employed f ous applications [23][24][25][26][27][28][29][30][31][32][33].

Scheme 1. Synthesis of 3a-g.
The structures of all new compounds were confirmed by the 1 H, 77 Se, and 13 spectroscopies; high-resolution electrospray ionization mass spectrometry (HRE IR; the elemental analyses (C, H, N); and X-ray diffraction analysis for 3b, 3f, and ure 1). Compounds 3b, 3f, and 3g could be recrystallized to furnish monocrystals, for analysis by single crystal X-ray crystallography. The structural investigatio firmed the formation of 2-selenoxo-1,2,3,4-tetrahydro-4-quinazolinones. The p mechanism for the formation of 3a-g is depicted in Scheme S1 and is similar to w observed in the S analogs [15]. The structures of all new compounds were confirmed by the 1 H, 77 Se, and 13 C NMR spectroscopies; high-resolution electrospray ionization mass spectrometry (HRESI-MS); IR; the elemental analyses (C, H, N); and X-ray diffraction analysis for 3b, 3f, and 3g ( Figure 1). Compounds 3b, 3f, and 3g could be recrystallized to furnish monocrystals, suitable for analysis by single crystal X-ray crystallography. The structural investigations confirmed the formation of 2-selenoxo-1,2,3,4-tetrahydro-4-quinazolinones. The plausible mechanism for the formation of 3a-g is depicted in Scheme 1 and is similar to what was observed in the S analogs [15].
can also be conveniently introduced via substitution of the SMe moiety on treatment with NaSeH [20]. Another widely spread approach to the synthesis of sulfur-containing deriv atives of quinazolinones involves the reaction between o-aminonitriles or o-aminocarbox ylates and isothiocyanates or thiourea. However, this approach has been studied little fo the preparation of derivatives of quinazolin-2(1Н)-selones, which is probably due to th lower stability and synthetic availability of isoselenocyanates [21,22]. It should be noted that interest in chacogen-containing derivatives of quinazolinones arises due to their po tential applications in supramolecular chemistry. Halogen and chalcogen bonding (ChB is an area of increasing interest, and these weak interactions are often employed for vari ous applications [23][24][25][26][27][28][29][30][31][32][33].

Scheme 1. Synthesis of 3a-g.
The structures of all new compounds were confirmed by the 1 H, 77 Se, and 13 C NMR spectroscopies; high-resolution electrospray ionization mass spectrometry (HRESI-MS) IR; the elemental analyses (C, H, N); and X-ray diffraction analysis for 3b, 3f, and 3g (Fig  ure 1). Compounds 3b, 3f, and 3g could be recrystallized to furnish monocrystals, suitabl for analysis by single crystal X-ray crystallography. The structural investigations con firmed the formation of 2-selenoxo-1,2,3,4-tetrahydro-4-quinazolinones. The plausibl mechanism for the formation of 3a-g is depicted in Scheme S1 and is similar to what wa observed in the S analogs [15]. Structural investigations revealed that the 2-selenoxo-1,2,3,4-tetrahydro-4quinazolinone fragment in 3b, 3f, and 3g is virtually planar, and the C=Se distances are within the typical range for the corresponding single bond values. Interestingly, compound 3f exhibited unsymmetrical supramolecular dimers via type II Se···Se ChB (Figure 1), while 3b and 3f were not engaged in ChB, arguably due to the prevalence of other weak interactions in the solid state. Theoretical calculations on the type II Se···Se ChB for compound 3f are given here further.
When we attempted to recrystallize 3c from ethanol, its aerobic oxidation coupled with the diselenide formation took place. Similar oxidations were observed earlier in the literature [22,48,49]. We were able to achieve synthetically viable oxidation for 3a-g to furnish 4a-g in good yields employing hydrogen peroxide as an oxidant (Scheme 2).

Figure 1.
Ball-and-stick representations of 3b, 3f, and 3g. Se···Se ChB for 3f is depic line. Grey and light grey spheres represent carbon and hydrogen atoms, respectivel Structural investigations revealed that the 2-selenoxo-1,2,3,4-tetrahydr none fragment in 3b, 3f, and 3g is virtually planar, and the C=Se distances typical range for the corresponding single bond values. Interestingly, compo ited unsymmetrical supramolecular dimers via type II Se···Se ChB ( Figure 1) 3f were not engaged in ChB, arguably due to the prevalence of other weak the solid state. Theoretical calculations on the type II Se···Se ChB for com given here further.
When we attempted to recrystallize 3c from ethanol, its aerobic oxid with the diselenide formation took place. Similar oxidations were observed literature [22,48,49]. We were able to achieve synthetically viable oxidatio furnish 4a-g in good yields employing hydrogen peroxide as an oxidant (S Scheme 2. Synthesis of 4a-g. Compounds 4a-g are poorly soluble in common organic solvents; how aged to obtain single crystals of 4b and 4c, suitable for X-Ray analysis (Figu  Structural investigations revealed that the 2-selenoxo-1,2,3,4-tetrahydro-4-quinazolinone fragment in 3b, 3f, and 3g is virtually planar, and the C=Se distances are within the typical range for the corresponding single bond values. Interestingly, compound 3f exhibited unsymmetrical supramolecular dimers via type II Se···Se ChB (Figure 1), while 3b and 3f were not engaged in ChB, arguably due to the prevalence of other weak interactions in the solid state. Theoretical calculations on the type II Se···Se ChB for compound 3f are given here further.
When we attempted to recrystallize 3c from ethanol, its aerobic oxidation coupled with the diselenide formation took place. Similar oxidations were observed earlier in the literature [22,48,49]. We were able to achieve synthetically viable oxidation for 3a-g to furnish 4a-g in good yields employing hydrogen peroxide as an oxidant (Scheme 2). Scheme 2. Synthesis of 4a-g.
In order to theoretically study chalcogen bonds Se···Se, Se···N, and Te···N observed in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, the DFT calculations followed by the topological analysis of the electron density distribution within the QTAIM approach [53] were carried out for model supramolecular associates (see Computational details and Table S1 in Supporting Information). The results of the QTAIM analysis are summarized in Table  1. The contour line diagrams of the Laplacian of electron density distribution  2 ⍴(r), bond paths, and selected zero-flux surfaces; visualization of electron localization function (ELF); and reduced density gradient (RDG) analyses for contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8 are shown in Figures 4-10; the visualization of these noncovalent interactions in 3D using NCI analysis technique [54] is shown in Figure  11. Table 1. Values of the density of all electrons-⍴(r), Laplacian of electron density- 2 ⍴(r) and appropriate λ2 eigenvalues, energy density-Hb, potential energy density-V(r), and Lagrangian kinetic energy-G(r) (a.u.) at the bond critical points (3, −1), corresponding to contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, and approximately estimated strength for these interactions Eint (kcal/mol) [55]. Compound 5 is a dibenzimidazole diselenide, as are 4b and 4c, which features two intramolecular Se···N ChB. For 6, the situation is slightly more complicated: each Se atom is involved in two intramolecular Se···N ChB, and overall, the molecule features four Se···N ChB ( Figure 3). Compounds 7 [51,52] and 8 [52], which were reported earlier, also featured intramolecular ChB, analogously to 4b and 4c.
In order to theoretically study chalcogen bonds Se···Se, Se···N, and Te···N observed in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, the DFT calculations followed by the topological analysis of the electron density distribution within the QTAIM approach [53] were carried out for model supramolecular associates (see Computational details and Table S1 in Supplementary Materials). The results of the QTAIM analysis are summarized in Table 1 e diselenide, as are 4b and 4c, which features two tuation is slightly more complicated: each Se atom ··N ChB, and overall, the molecule features four 1,52] and 8 [52], which were reported earlier, also sly to 4b and 4c. lcogen bonds Se···Se, Se···N, and Te···N observed in d 8, the DFT calculations followed by the topologstribution within the QTAIM approach [53] were ssociates (see Computational details and Table S1 s of the QTAIM analysis are summarized in Table  lacian  (r), bond paths, and selected zero-flux surfaces; visualization of electron localization function (ELF); and reduced density gradient (RDG) analyses for contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8 are shown in Figures 4-10; the visualization of these noncovalent interactions in 3D using NCI analysis technique [54] is shown in Figure 11.  (Figure 3). Compounds 7 [51,52] and 8 [52], which were reported earlier, also featured intramolecular ChB, analogously to 4b and 4c.

Contact *
rating intramolecular Se···N ChB, depicted arbon and hydrogen atoms, respectively. , as are 4b and 4c, which features two ightly more complicated: each Se atom d overall, the molecule features four [52], which were reported earlier, also d 4c. s Se···Se, Se···N, and Te···N observed in T calculations followed by the topologithin the QTAIM approach [53] were ee Computational details and Table S1 AIM analysis are summarized in Table  ectron  zole diselenide, as are 4b and 4c, which features two e situation is slightly more complicated: each Se atom Se···N ChB, and overall, the molecule features four 7 [51,52] and 8 [52], which were reported earlier, also gously to 4b and 4c. halcogen bonds Se···Se, Se···N, and Te···N observed in , and 8, the DFT calculations followed by the topologdistribution within the QTAIM approach [53] were ar associates (see Computational details and Table S1 ults of the QTAIM analysis are summarized in Table  Laplacian of  Hb    Compound 5 is a dibenzimidazole diselenide, as are 4b and 4c, which features two intramolecular Se···N ChB. For 6, the situation is slightly more complicated: each Se atom is involved in two intramolecular Se···N ChB, and overall, the molecule features four Se···N ChB (Figure 3). Compounds 7 [51,52] and 8 [52], which were reported earlier, also featured intramolecular ChB, analogously to 4b and 4c.
In order to theoretically study chalcogen bonds Se···Se, Se···N, and Te···N observed in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, the DFT calculations followed by the topological analysis of the electron density distribution within the QTAIM approach [53] were carried out for model supramolecular associates (see Computational details and Table S1 in Supporting Information). The results of the QTAIM analysis are summarized in Table  1. The contour line diagrams of the Laplacian of electron density distribution  2 ⍴(r), bond paths, and selected zero-flux surfaces; visualization of electron localization function (ELF); and reduced density gradient (RDG) analyses for contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8 are shown in Figures 4-10; the visualization of these noncovalent interactions in 3D using NCI analysis technique [54] is shown in Figure  11. Table 1. Values of the density of all electrons-⍴(r), Laplacian of electron density- 2 ⍴(r) and appropriate λ2 eigenvalues, energy density-Hb, potential energy density-V(r), and Lagrangian kinetic energy-G(r) (a.u.) at the bond critical points (3, −1), corresponding to contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, and approximately estimated strength for these interactions Eint (kcal/mol) [55].    Compound 5 is a dibenzimidazole diselenide, as are 4b and 4c, which features two intramolecular Se···N ChB. For 6, the situation is slightly more complicated: each Se atom is involved in two intramolecular Se···N ChB, and overall, the molecule features four Se···N ChB (Figure 3). Compounds 7 [51,52] and 8 [52], which were reported earlier, also featured intramolecular ChB, analogously to 4b and 4c.

Contact *
In order to theoretically study chalcogen bonds Se···Se, Se···N, and Te···N observed in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, the DFT calculations followed by the topological analysis of the electron density distribution within the QTAIM approach [53] were carried out for model supramolecular associates (see Computational details and Table S1 in Supporting Information). The results of the QTAIM analysis are summarized in Table  1. The contour line diagrams of the Laplacian of electron density distribution  2 ⍴(r), bond paths, and selected zero-flux surfaces; visualization of electron localization function (ELF); and reduced density gradient (RDG) analyses for contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8 are shown in Figures 4-10; the visualization of these noncovalent interactions in 3D using NCI analysis technique [54] is shown in Figure  11. Table 1. Values of the density of all electrons-⍴(r), Laplacian of electron density- 2 ⍴(r) and appropriate λ2 eigenvalues, energy density-Hb, potential energy density-V(r), and Lagrangian kinetic energy-G(r) (a.u.) at the bond critical points (3, −1), corresponding to contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, and approximately estimated strength for these interactions Eint (kcal/mol) [55].   Compound 5 is a dibenzimidazole diselenide, as are 4b and 4c, which features two intramolecular Se···N ChB. For 6, the situation is slightly more complicated: each Se atom is involved in two intramolecular Se···N ChB, and overall, the molecule features four Se···N ChB (Figure 3). Compounds 7 [51,52] and 8 [52], which were reported earlier, also featured intramolecular ChB, analogously to 4b and 4c.
In order to theoretically study chalcogen bonds Se···Se, Se···N, and Te···N observed in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, the DFT calculations followed by the topological analysis of the electron density distribution within the QTAIM approach [53] were carried out for model supramolecular associates (see Computational details and Table S1 in Supporting Information). The results of the QTAIM analysis are summarized in Table  1. The contour line diagrams of the Laplacian of electron density distribution  2 ⍴(r), bond paths, and selected zero-flux surfaces; visualization of electron localization function (ELF); and reduced density gradient (RDG) analyses for contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8 are shown in Figures 4-10; the visualization of these noncovalent interactions in 3D using NCI analysis technique [54] is shown in Figure  11. Table 1. Values of the density of all electrons-⍴(r), Laplacian of electron density- 2 ⍴(r) and appropriate λ2 eigenvalues, energy density-Hb, potential energy density-V(r), and Lagrangian kinetic energy-G(r) (a.u.) at the bond critical points (3, −1), corresponding to contacts Se···Se, Se···N, and Te···N in the X- ray structures 3f, 4b, 4c, 5, 6, 7, and 8, and approximately estimated strength for   (ELF, center), and reduced density gradient (RDG, right) analyses for contacts Se-Se and Se···N in the X-ray structure 4c. Bond critical points (3, -1) are shown in blue, nuclear critical points (3, -3)-pale brown, ring critical points (3, +1)-orange, bond paths are shown as pale brown lines, length units-Å, and the color scale for the ELF and RDG maps is presented in a.u.   Compound 5 is a dibenzimidazole diselenide, as are 4b and 4c, which features two intramolecular Se···N ChB. For 6, the situation is slightly more complicated: each Se atom is involved in two intramolecular Se···N ChB, and overall, the molecule features four Se···N ChB (Figure 3). Compounds 7 [51,52] and 8 [52], which were reported earlier, also featured intramolecular ChB, analogously to 4b and 4c.
In order to theoretically study chalcogen bonds Se···Se, Se···N, and Te···N observed in the X- ray structures 3f, 4b, 4c, 5, 6, 7, and 8, the DFT calculations followed by the topological analysis of the electron density distribution within the QTAIM approach [53] were carried out for model supramolecular associates (see Computational details and Table S1 in Supporting Information). The results of the QTAIM analysis are summarized in Table  1. The contour line diagrams of the Laplacian of electron density distribution  2 ⍴(r), bond paths, and selected zero-flux surfaces; visualization of electron localization function (ELF); and reduced density gradient (RDG) analyses for contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8 are shown in Figures 4-10; the visualization of these noncovalent interactions in 3D using NCI analysis technique [54] is shown in Figure  11. Table 1. Values of the density of all electrons-⍴(r), Laplacian of electron density- 2 ⍴(r) and appropriate λ2 eigenvalues, energy density-Hb, potential energy density-V(r), and Lagrangian kinetic energy-G(r) (a.u.) at the bond critical points (3, −1), corresponding to contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, and approximately estimated strength for these interactions Eint (kcal/mol) [55].    Compound 5 is a dibenzimidazole diselenide, as are 4b and 4c, which features two intramolecular Se···N ChB. For 6, the situation is slightly more complicated: each Se atom is involved in two intramolecular Se···N ChB, and overall, the molecule features four Se···N ChB (Figure 3). Compounds 7 [51,52] and 8 [52], which were reported earlier, also featured intramolecular ChB, analogously to 4b and 4c.

Contact *
In order to theoretically study chalcogen bonds Se···Se, Se···N, and Te···N observed in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, the DFT calculations followed by the topological analysis of the electron density distribution within the QTAIM approach [53] were carried out for model supramolecular associates (see Computational details and Table S1 in Supporting Information). The results of the QTAIM analysis are summarized in Table  1. The contour line diagrams of the Laplacian of electron density distribution  2 ⍴(r), bond paths, and selected zero-flux surfaces; visualization of electron localization function (ELF); and reduced density gradient (RDG) analyses for contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8 are shown in Figures 4-10; the visualization of these noncovalent interactions in 3D using NCI analysis technique [54] is shown in Figure  11. Table 1. Values of the density of all electrons-⍴(r), Laplacian of electron density- 2 ⍴(r) and appropriate λ2 eigenvalues, energy density-Hb, potential energy density-V(r), and Lagrangian kinetic energy-G(r) (a.u.) at the bond critical points (3, −1), corresponding to contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, and approximately estimated strength for these interactions Eint (kcal/mol) [55].  Compound 5 is a dibenzimidazole diselenide, as are 4b and 4c, which features two intramolecular Se···N ChB. For 6, the situation is slightly more complicated: each Se atom is involved in two intramolecular Se···N ChB, and overall, the molecule features four Se···N ChB (Figure 3). Compounds 7 [51,52] and 8 [52], which were reported earlier, also featured intramolecular ChB, analogously to 4b and 4c.

Contact *
In order to theoretically study chalcogen bonds Se···Se, Se···N, and Te···N observed in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, the DFT calculations followed by the topological analysis of the electron density distribution within the QTAIM approach [53] were carried out for model supramolecular associates (see Computational details and Table S1 in Supporting Information). The results of the QTAIM analysis are summarized in Table  1. The contour line diagrams of the Laplacian of electron density distribution  2 ⍴(r), bond paths, and selected zero-flux surfaces; visualization of electron localization function (ELF); and reduced density gradient (RDG) analyses for contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8 are shown in Figures 4-10; the visualization of these noncovalent interactions in 3D using NCI analysis technique [54] is shown in Figure  11. Table 1. Values of the density of all electrons-⍴(r), Laplacian of electron density- 2 ⍴(r) and appropriate λ2 eigenvalues, energy density-Hb, potential energy density-V(r), and Lagrangian kinetic energy-G(r) (a.u.) at the bond critical points (3, −1), corresponding to contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8, and approximately estimated strength for these interactions Eint (kcal/mol) [55].   (ELF, center), and reduced density gradient (RDG, right) analyses for contacts Se-Se and Se···N in the X-ray structure 7. Bond critical points (3, -1) are shown in blue, nuclear critical points (3, -3)-pale brown, ring critical points (3, +1)-orange, bond paths are shown as pale brown lines, length units-Å, and the color scale for the ELF and RDG maps is presented in a.u. The QTAIM analysis of model supramolecular associates demonstrates the presence of bond critical points (3, -1) for contacts Se···Se, Se···N, and Te···N in the X-ray structures 3f, 4b, 4c, 5, 6, 7, and 8 (Table 1 and Figures 4-10). The low magnitude of the electron density, positive values of the Laplacian of electron density, and very close to zero energy density in bond critical points (3, -1) for chalcogen bonds Se···Se (3f) and Se···N (4b, 4c, 5, 6, and 7) or Te···N (8) in studied model supramolecular associates, as well as their estimated strength, are typical for noncovalent interactions involving chalcogen atoms  Compound 5 is a dibenzimidazole diselenide, as are 4b and 4c, which features two intramolecular Se···N ChB. For 6, the situation is slightly more complicated: each Se atom is involved in two intramolecular Se···N ChB, and overall, the molecule features four Se···N ChB (Figure 3). Compounds 7 [51,52] and 8 [52], which were reported earlier, also featured intramolecular ChB, analogously to 4b and 4c.

Materials and Methods
Methyl anthranilate (Acros Organics, Belgium) was used in this work without additional purification. The isoselenocyanates 2 a-g used in this work were obtained by the literature method [65]. Isoselenocyanates 2b, c, g were purified by recrystallization from hexane at −20 °C. Ethanol was dried by distillation over CaO and CaH2.
All melting points were determined with a "Stuart SMP3" melting point apparatus. Infrared spectra were recorded on the "Shimadzu IR Prestige-21" (Kyoto, Japan) instrument in KBr disk (4000-400 cm -1 ). High-resolution mass spectra (HR-MS) were measured on a "Bruker micrOTOF II" (Karlsruhe, Germany) instrument using electrospray ionization (ESI). The measurements were performed in a positive ion mode (interface capillary voltage −4500 V); mass range from m/z 50 to m/z 30 0 0 Da; internal calibration was performed with Electrospray Calibrant Solution («Agilent Tuning Mix», «Agilent»). The most intensive peak in the isotopic pattern was reported. A syringe injection was used for solutions in acetonitrile (flow rate 5 McL/min). Nitrogen was applied as a dry gas; interface temperature was set at 180 °C. 1 H, COSY, 13 C-NMR, DEPT, HSQC, and HMBC spectra compounds 3a-f were measured on an "Agilent DD2 400" spectrometer (400 MHz for 1 H and 100.60 MHz for 13 C, Santa Clara, CA, USA) using DMSO-d6 as the NMR solvents. Chemical shifts were indicated in parts per million (ppm) relative to tetramethylsilane as an internal standard. The 77 Se-NMR spectra compound 3a-f were measured on an "Agilent DD2 400" spectrometer at 76.30 MHz using diphenylselenide as a standard. The 19 F-NMR spectra compound 3e Figure 11. Visualization of noncovalent interactions Se···Se, Se···N, and Te···N in 3D using NCI analysis technique in model supramolecular associates 3f, 6, 7, and 8.

Materials and Methods
Methyl anthranilate (Acros Organics, Belgium) was used in this work without additional purification. The isoselenocyanates 2 a-g used in this work were obtained by the literature method [65]. Isoselenocyanates 2b, c, g were purified by recrystallization from hexane at −20 • C. Ethanol was dried by distillation over CaO and CaH 2 .
All melting points were determined with a "Stuart SMP3" melting point apparatus. Infrared spectra were recorded on the "Shimadzu IR Prestige-21" (Kyoto, Japan) instrument in KBr disk (4000-400 cm −1 ). High-resolution mass spectra (HR-MS) were measured on a "Bruker micrOTOF II" (Karlsruhe, Germany) instrument using electrospray ionization (ESI). The measurements were performed in a positive ion mode (interface capillary voltage −4500 V); mass range from m/z 50 to m/z 30 0 0 Da; internal calibration was performed with Electrospray Calibrant Solution («Agilent Tuning Mix», «Agilent»). The most intensive peak in the isotopic pattern was reported. A syringe injection was used for solutions in acetonitrile (flow rate 5 McL/min). Nitrogen was applied as a dry gas; interface temperature was set at 180 • C. 1 H, COSY, 13 C-NMR, DEPT, HSQC, and HMBC spectra compounds 3a-f were measured on an "Agilent DD2 400" spectrometer (400 MHz for 1 H and 100.60 MHz for 13 C, Santa Clara, CA, USA) using DMSO-d6 as the NMR solvents. Chemical shifts were indicated in parts per million (ppm) relative to tetramethylsilane as an internal standard. The 77 Se-NMR spectra compound 3a-f were measured on an "Agilent DD2 400" spectrometer at 76.30 MHz using diphenylselenide as a standard. The 19 F-NMR spectra compound 3e were measured on an "Agilent DD2 400" spectrometer at 376.30 MHz using trichlorofluoromethane as a standard. The 1 H, COSY, 13 C, JMODECHO, HSQC, and HMBC compounds 3g were measured on a "Bruker Avance TM 600" (Karlsruhe, Germany) spectrometer (600 MHz for 1 H and 150.925 MHz for 13 C) using DMSO-d6 as the NMR solvents. The 1 H, COSY, 13 C, JMODECHO, HSQC, and HMBC compounds 4a-g were measured on a "Bruker Avance TM 500" spectrometer (500 MHz for 1 H and 125.72 MHz for 13 C) using DMSO-d6 as the NMR solvents. The 77 Se-NMR spectra compounds, 3g and 4a-g, were measured on a "Bruker Avance TM 400" spectrometer at 76. 35 MHz and referenced to diphenylselenide, using DMSO-d6 as the NMR solvents. The 19 F-NMR spectra compounds, 3g, 4e, and 4g, were measured on a "Bruker Avance TM 300" spectrometer at 282.38 MHz and referenced to trichlorofluoromethane, using DMSO-d6 as NMR solvent.

Synthetic Part
Synthesis of compounds 3a-g (general method). To a solution (0.01 mol) of methyl anthranilate, 1 in 100 mL of absolute ethanol (0.01 mol) of the corresponding isoselenocyanate 2 a-g in 20 mL of absolute ethanol was added, boiled for 6 h, then cooled to 0 • C. Precipitates precipitated from the solution were separated by filtration, washed with ethanol (2 × 25 mL), and dried at 40 • C. trichlorofluoro-methane as a standard. The 1 H, COSY, 13 C, JMODECHO, HSQC, and HMBC compounds 3g were measured on a "Bruker Avance TM 600" (Karlsruhe, Germany) spectrometer (600 MHz for 1 H and 150.925 MHz for 13 C) using DMSO-d6 as the NMR solvents. The 1 H, COSY, 13 C, JMODECHO, HSQC, and HMBC compounds 4a-g were measured on a "Bruker Avance TM 500" spectrometer (500 MHz for 1 H and 125.72 MHz for 13 C) using DMSO-d6 as the NMR solvents. The 77 Se-NMR spectra compounds, 3g and 4ag, were measured on a "Bruker Avance TM 400" spectrometer at 76. 35 MHz and referenced to diphenylselenide, using DMSO-d6 as the NMR solvents. The 19 F-NMR spectra compounds, 3g, 4e, and 4g, were measured on a "Bruker Avance TM 300" spectrometer at 282. 38 MHz and referenced to trichlorofluoromethane, using DMSO-d6 as NMR solvent.

Synthetic Part
Synthesis of compounds 3a-g (general method). To a solution (0.01 mol) of methyl anthranilate, 1 in 100 mL of absolute ethanol (0.01 mol) of the corresponding isoselenocyanate 2 a-g in 20 mL of absolute ethanol was added, boiled for 6 h, then cooled to 0 °C. Precipitates precipitated from the solution were separated by filtration, washed with ethanol (2 × 25 mL), and dried at 40 °C.    such contacts. The existence of all the above-mentioned ChB was additionally confirmed by DFT calculations followed by the topological analysis of the electron density distribution.