Recent developments in the synthesis and applications of terpyridine-based metal complexes: a systematic review.

Terpyridine-based metal complexes have emerged as versatile and indispensable building blocks in the realm of modern chemistry, offering a plethora of applications spanning from materials science to catalysis and beyond. This comprehensive review article delves into the multifaceted world of terpyridine complexes, presenting an overview of their synthesis, structural diversity, and coordination chemistry principles. Focusing on their diverse functionalities, we explore their pivotal roles in catalysis, supramolecular chemistry, luminescent materials, and nanoscience. Furthermore, we highlight the burgeoning applications of terpyridine complexes in sustainable energy technologies, biomimetic systems, and medicinal chemistry, underscoring their remarkable adaptability to address pressing challenges in these fields. By elucidating the pivotal role of terpyridine complexes as versatile building blocks, this review provides valuable insights into their current state-of-the-art applications and future potential, thus inspiring continued innovation and exploration in this exciting area of research.

Study on Regio- and Diastereoselectivity of the 1,3-Dipolar Cycloaddition Reaction of Azomethine Ylide with 2-(Benzo[d]thiazol-2-yl)-3-(aryl)acrylonitrile: Synthesis, Spectroscopic, and Computational Approach.

An unprecedented and efficient three-component 1,3-dipolar cycloaddition reaction using (E)-2-(benzo[d]thiazol-2-yl)-3-(aryl)acrylonitriles 4a-g and an in situ generated azomethine ylide 3 from isatin and N-methylglycine is described. The reaction exhibits exclusive regioselectivity, resulting in the formation of 3'-(benzo[d]thiazol-2-yl)-1'-methyl-2-oxo-4'-(aryl)spiro[indoline-3,2'-pyrrolidine]-3'-carbonitriles regioisomers through exo/endo approaches. The diastereoselectivity of the reaction is highly dependent on the substitution pattern of the phenyl ring in dipolarophiles 4a-g, leading to the formation of exo-/endo-cycloadducts in varying ratios. To understand the stereoselectivity, the transition state structures were optimized using the TS guess geometry with the QST3-based method. The reaction mechanism and regioselectivity were elucidated by evaluating global and local electrophilicity and nucleophilicity descriptors at the B3LYP/cc-pVTZ level of theory, along with considerations based on the HSAB principle. The analysis of global electron density transfer (GEDT) showed that the reactions are polar and electron density fluxes from azomethine ylide 3 toward dipolarophile 4a-g. It was found from the molecular electrostatic potential map (MESP) that at the more favorable transition state, approach of reactants locates the oppositely charged regions over each other resulting in attractive forces between the two fragments. The computational results are consistent with the experimental observations, confirming that the reactions proceed through an asynchronous one-step mechanism.

Exploring the untapped pharmacological potential of imidazopyridazines.

Imidazopyridazines are fused heterocycles, like purines, with a pyridazine ring replacing the pyrimidine ring in purines. Imidazopyridazines have been primarily studied for their kinase inhibition activity in the development of new anticancer and antimalarial agents. In addition to this, they have also been investigated for their anticonvulsant, antiallergic, antihistamine, antiviral, and antitubercular properties. Herein, we review the background and development of different imidazopyridazines as potential pharmacological agents. Moreover, the scope of this relatively less charted heterocyclic scaffold is also highlighted.