Synthesis, Characterization, DFT Study, and In Silico Evaluation of a Thiophene-Thiazole Scaffolds as a Potential Mycobacterium tuberculosis CYP51 Inhibitor

A thiazole–thiophene derivative, (E)-4-(2-(2-(1-(5-chlorothiophen-2-yl)ethylidene)hydrazinyl)thiazol-4-yl)benzonitrile (CTHTBN), was synthesized via a one-pot multicomponent reaction involving 5-chloro-2-acetylthiophene, thiosemicarbazide, and 4-(2-bromoacetyl)benzonitrile. The synthesized compound was characterized by FT-IR, ¹H NMR, and ¹³C NMR spectroscopy, confirming the formation of the target molecule. Density Functional Theory (DFT) calculations at the B3LYP/6-311G(d,p) level were performed to explore the electronic structure and reactivity of CTHTBN. The HOMO and LUMO energies were found to be –5.75 eV and –2.03 eV, respectively, with an energy gap (E_g) of 3.72 eV, suggesting a balanced chemical stability and reactivity. The dipole moment of 7.9381 Debye indicated substantial polarity, favourable for biological interactions. Global reactivity descriptors, including chemical hardness (η = 1.86 eV), chemical softness (σ = 0.5376 eV⁻¹), electronegativity (χ = 3.89 eV), electrophilicity index (ω = 4.07 eV), and maximum charge transfer capacity (ΔN_max = 2.09), further supported the molecule’s electronic competence. Molecular docking studies against Mycobacterium tuberculosis Cytochrome P450 14α-sterol demethylase (CYP51) demonstrated a strong binding affinity with a docking score of –8.7 kcal/mol. The binding interactions involved conventional hydrogen bonds, π–π stacking, π–σ, π–sulfur, alkyl, and π–alkyl interactions, stabilizing the compound within the enzyme’s active site. These findings suggest that CTHTBN holds promising potential as an antimycobacterial agent targeting CYP51 and warrants further biological evaluation.