A family of silatrane‐armed triazole‐encapped salicylaldehyde‐derived Schiff bases: Synthesis, spectral analysis, and antimicrobial and quantum chemical evaluation

Abstract

This work describes the successful synthesis of salicylaldehyde-derived Schiff baselinked organosilicon compounds following a highly efficient click approach. Hydroxyl-terminated Schiff bases were alkylated to bis-acetylenes (1-3) which upon 3 + 2 cycloaddition with 3-azidopropyltriethoxysilane yielded triazole-decorated bis-silanes (4-6). These silanes further underwent base-catalyzed transesterification to afford Schiff base-linked triazole-bound organosilatranes (7-9). The final silatranes as well as precursor alkynes and silanes were comprehensively characterized using NMR ( 1 H and 13 C) and infrared spectroscopic techniques together with elemental analysis and mass spectrometry of compounds 7-9. Also, the structures of alkynes 1-3 and silatrane 7 were validated using single-crystal X-ray crystallography. Organosilatranes were initially screened for their pharmacokinetic profile using absorption, distribution, metabolism, excretion and toxicity (ADMET) tools and then explored for their antimicrobial activities, with compound 9 emerging as the most potent antimicrobial agent. Compounds 1-3 and 7-9 also underwent thorough computational analysis by applying the density functional theory (DFT) approach with B3LYP/6-31G(d) level of theory and the results were found to be consistent with the experimental data. Several DFT-based descriptors were also evaluated providing a valuable insight into molecular stability and reactivity.

New atranes and similar ionic complexes. Synthesis, structure, properties

“…Functionalization of silatranes with different groups in exocyclic position is an important trend as the resulting compounds retain the activities of silatranes as well as substituted groups …”

“…For example, silatranes. Due to their unusual architecture (the N → Si bond, the pentacoordinated silicon atom, the tricyclic structure), high dipole moment and strong electron‐donating effect of the silatrane skeleton, silatranes are of interest not only as theoretical objects but also as important functional reagents, advanced materials (Si‐organic polyimide films, catalysts, optical probes, adhesion layers for nanoparticles), as well as physiologically and pharmacologically active compounds …”

Isoxazole derivatives of silatrane: synthesis, characterization, in silico ADME profile, prediction of potential pharmacological activity and evaluation of antimicrobial action

“…In addition, 3‐aminopropylsilatranes and their derivatives show antimicrobial, [ 12,13 ] antiparasitic, [ 14 ] antihepatitis B, [ 15 ] antitumor, [ 16 ] immunomodulatory [ 17 ] and growth stimulating [ 18 ] activity.…”

“…[ 27,28 ] The MG approach is based on the principle “two heads are better than one”, which has been successfully employed to create novel hybrid compounds with anticancer, anti‐inflammatory, antimicrobial, and other activities. [ 12–14,29–33 ]…”

An Overview of Recent Advances in the Applications of Click Chemistry in the Synthesis of Bioconjugates with Anticancer Activities

“…The copper‐catalyzed 1,3‐dipolar cycloaddition of an azide to a terminal alkyne is an easy route to tolerate a wide diversity of functional groups. The CuAAC reaction gives excellent yields and has been applied in organic synthesis, materials science, catalysis, and the biochemistry …”