Two metal complex derivatives of pyridine thiazole ligand: synthesis, characterization and biological activity

Supported-amine-catalyzed cascade synthesis of spiro-thiazolone-tetrahydrothiophenes: assessing HSA binding activity

We have devised a supported-amine-catalyzed efficient synthesis of spiro-thiazolone-tetrahydrothiophenes via a sulfa-Michael/aldol cascade approach. The catalyst demonstrated sustained efficacy over 21 cycles. These derivatives were found to exhibit excellent binding abilities with purified human serum albumin as indicated by both in silico and in vitro-based experiments.

Synthesis and Characterization of New Mixed-Ligand Complexes; Density Functional Theory, Hirshfeld, and In Silico Assays Strengthen the Bioactivity Performed In Vitro

N'-Acetyl-2-cyanoacetohydrazide (H₂L¹) and 2-cyano-N-(6-ethoxybenzo thiazol-2-yl) acetamide (HL²) ligands were used to synthesize [Cr(OAc)(H₂L¹)(HL²)]·2(OAc) and [Mn(H₂L¹)(HL²)]·Cl₂·2H₂O as mixed ligand complexes. All new compounds were analyzed by analytical, spectral, and computational techniques to elucidate their chemical formulae. The bidentate nature was suggested for each coordinating ligand via ON donors. The electronic transitions recorded are attributing to ⁴A₂g(F) → ⁴T₂g(F)(υ₂) and ⁴A₂g(F) → ⁴T₁g(F)(υ₃) types in the octahedral Cr(III) complex, while ⁶A₁ → ⁴T₂(G) and ⁶A₁ → ⁴T₁(G) transitions are attributing to the tetrahedral Mn(II) complex. These complexes were optimized by the density functional theory method to verify the bonding mode which was suggested via N(3), O(8), N(9), and N(10) donors from the mixed-ligands. Hirshfeld crystal models were demonstrated for the two ligands to indicate the distance between the functional groups within the two ligands and supporting the exclusion of self-interaction in between. Finally, the biological activity of the two mixed ligand complexes was tested by in silico ways as well as in vitro ways for confirmation. Three advanced programs were applied to measure the magnitude of biological efficiency of the two complexes toward kinase enzyme (3nzs) and breast cancer proliferation (3hy3). All in silico data suggest the superiority of the Mn(II) complex. Moreover, the in vitro assays for the two complexes that measure their antioxidant and cytotoxic activity support the distinguished activity of the Mn(II) complex.

5-N-Arylaminothiazoles with pyridyl groups and their first-row transition metal complexes: synthesis, photophysical properties, and Zn sensing

A series of 5-N-arylaminothiazoles were synthesized with facile diversity-oriented synthesis from readily available starting materials via the reaction of thioamide dianions and thioformamides. The introduction of various substituents at the 2-position of a thiazole ring (i.e., 2-pyridyl, 4-methylpyridyl, and phenyl groups) and on the nitrogen atom (i.e., p-tolyl and phenyl groups) significantly influenced the absorption and emission spectra of the isolated compounds. X-ray analysis confirmed that the substituents at the amino site were twisted from a thiazole ring, while the formation of its nickel complex showed dinuclear metal complexes bridged with chlorine atoms. Moreover, the formation of zinc-thiazole complexes showed enhanced emission properties in solution and noticeable emission in a solid state. In addition, thiazole-bridged dypyrromethene type ligands showed high selectivity toward Zn+2, which make them good candidates for zinc sensing.