Synthesis and X-ray Crystal Structure Analysis of Substituted 1,2,4-Triazolo [4’,3’:2,3]pyridazino[4,5-b]indole and Its Precursor

The hit compound 1,2,4-triazolo[4’,3’:2,3]pyridazino[4,5-b]indole 3 was synthesized from the reflux of 4-amino-5-indolyl-1,2,4-triazole-3-thione 1 with 4′-bromoacetophenone 2 in methanol catalyzed by concentrated HCl and desired final molecule obtained recrystallization methanol. suggested structures compounds based on spectral characterizations were confirmed X-ray single crystal diffraction analysis. Compound crystallized triclinic system P-1 space group a = 5.9308(2) Å, b 10.9695(3) c 14.7966(4) α 100.5010(10)°, β 98.6180(10)°, γ 103.8180(10)°. On other hand, is monoclinic, where 6.23510(10) 26.0156(4) 12.4864(2) 93.243(2)° P21. triazole indole rings are found twisted each both compounds. twist angle higher (12.65°) than (4.94–7.22°). In case former, H…H (39.6%), H…C (22.0%), N…H (12.8%) Br…H (13.2%) contacts most dominant while C…C, C…H, Br…H, S…S have characteristics strong interactions. latter, N…H, S…H, S…S, C…C important. this case, percentages H…H, S…H range 34.9–37.4, 20.5–24.0, 12.2–13.6, 14.0–15.8, respectively. systems, shape index curvedness surfaces presence π–π stacking