Complexes of the plant hormone gibberellic acid with the Pt(II), Au(III), Ru(III), V(III), and Se(IV) ions: preparation, characterization, and in vitro evaluation of biological activity

Stereoselective Synthesis and Application of Gibberellic Acid-Derived Aminodiols

A series of gibberellic acid-based aminodiols was designed and synthesized from commercially available gibberellic acid. Exposure of gibberellic acid to hydrochloric acid under reflux conditions resulted in aromatization followed by rearrangement to form allo-gibberic acid. The key intermediate, ethyl allo-gibberate, was prepared according to literature methods. Epoxidation of key intermediate and subsequent ring-opening of the corresponding epoxide with different nucleophiles resulted in N-substituted aminodiols. The regioselective ring closure of N-benzyl-substituted aminodiol with formaldehyde was also investigated. All aminodiol derivatives were well characterized using modern spectroscopic techniques and evaluated for their antiproliferative activity against a panel of human cancer cell lines. In addition, structure–activity relationships were examined by assessing substituent effects on the aminodiol systems. The results indicated that aminodiols containing aromatic rings on their nitrogen substituents displayed significant cytotoxic effects. Among these agents, N-naphthylmethyl-substituted aminodiols were found to be the most potent candidates in this series. One of these molecules exhibited a modest cancer selectivity determined by non-cancerous fibroblast cells. A docking study was also made to exploit the observed results.

Theoretical investigation on orange-emitting cyclometalated platinum (II) complexes containing organosilyl/organocarbon-substituted 2-(2-thienyl)pyridine ligands

This paper presents a theoretical investigation of structural, optical, and phosphorescence properties of four cyclometalated Pt(II) complexes containing substituted 2-(2-thienyl)pyridine ligands using DFT and TD-DFT methods. Geometrical parameters of ground states were calculated and compared with available experimental data. Electronic absorptions were studied and assigned in terms of natural transition orbitals. Phosphorescence spectra have been simulated with adiabatic Hessian and adiabatic shift approaches according to the Franck-Condon approximation. Theoretical and experimental results agree and show that the four complexes exhibit two intense bands in orange region. Main normal modes involved in phosphorescence bands were analyzed and assigned.

New Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Zn(II), Cd(II), and Hg(II) Gibberellate Complexes: Synthesis, Structure, and Inhibitory Activity Against COVID-19 Protease

Transition metals such as Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Zn(II), Cd(II), and Hg(II) have been reacted with gibberellic acid (HGA) to give novel complexes, and those have been characterized by physical, spectral and analytical methods. The plant hormone gibberellate acts as a deprotonated bidentate ligand in the complexation reaction with central metal ions in the ratio 1 : 2 (M ⁿ⁺ : GA). The complexes [M(GA)₂(H₂O)₂], where [M = Mn(II), Co(II), and Ni(II)] form octahedral structures, while [M(GA)₂] complexes [M = Zn(II), Cd(II), and Hg(II)] display four-coordination geometry. The octahedral structures of Cr(III) and Fe(III) complexes are characterized by the general formula [M(GA)₂(H₂O)(Cl)]. Computational study carried out has determined possible interactions of the complexes with COVID-19 (6LU7).