New Hybrid (E)-4-((pyren-1-ylmethylene)amino)-N-(thiazol- 2-yl)benzenesulfonamide as a Potential Drug Candidate: Spectroscopy, TD-DFT, NBO, FMO, and MEP Studies
Abstract
A novel pyrene-sulfathiazole-based potential drug candidate 3
was designed, successfully synthesized by a condensation
reaction of pyrenecarboxaldehyde (1) with sulfathiazole (2) in
good yield, and fully characterized by NMR, IR, UV-Vis, and
HRMS spectroscopic techniques. The TD-DFT/B3LYP calculations
displayed that the recorded peaks at 396, 377, 280, and
236 nm were due to the mainly n-π* and partially π-π*
transitions that occurred on pyrene, azomethine, and sulfathiazole
moieties. The NBO results disclosed that the electron
delocalizations happened onto sulfathiazole, aromatic rings
(pyrene and Ph-), and azomethine groups had the main
responsibility of the lowering stabilization energy of compound
3. The NMR shifts were calculated by using the GIAO
approaches in the DMSO phase and compared with the
relevant data recorded. The thermodynamic and quantum
chemical quantities were used for elucidating the physicochemical
properties and reactivity behavior, in THF, DMSO, and
water simulation environments. Accordingly, the calculated DM
(D) and α (au) order of compound 3 were calculated in the
order of vacuum<THF<DMSO<water, which indicated that
the stability and thus reactivity of the compound strongly
depended on the solvent environment. The FMO studies
implied that the electron-donating possibility of compound 3
was dominant to the electron-accepting potency. In this work,
the SMD version of IEFPCM was used in solvent media
simulations