The visible light promoted cross-dehydrogenative coupling reaction has emerged as an excellent strategy for the direct formation of C–C/C–heteroatom bonds from simple compounds. The use of renewable energy resources without the need for prefunctionalization of the reactant synergistically promote the synthetic pathway towards green synthesis. Although the introduction of the terminology “cross-dehydrogenative coupling (CDC)” was done by Li’s group in 2004, visible light promoted CDC has attracted tremendous attention from synthetic chemists since the first report of Ir-photocatalysis by Stephenson et al. in 2010. The efficiency of different transition-metal salts (Ir-, Ru-, Rh-, Cu-, Pt-, Co-, etc.), organic molecules (eosin Y, eosin B, rose bengal, rhodamine, methylene blue, acridines, etc.), I₂, and heterogeneous catalysts as photocatalysts in this transformation has been extensively investigated during this period. A number of methodologies have been also developed under visible light irradiation even in the absence of any photocatalysts. In this review, all the visible light promoted cross-dehydrogenative coupling methodologies developed over the last decade have been disclosed. Furthermore, the applicability and the mechanistic pathways of the methodologies have been also discussed.

The enzyme Phosphodiesterase 10A (PDE10A) plays a regulatory role in the cAMP/protein kinase A (PKA) signaling pathway by means of hydrolyzing cAMP and cGMP. PDE10A emerges as a relevant pharmacological drug target for neurological conditions such as psychosis, schizophrenia, Parkinson's, Huntington’s disease, and other memory-related disorders. In the current study, we subjected a set of 1,2,3-triazoles to be explored as PDE10A inhibitors using diverse computational approaches, including molecular docking, classical molecular dynamics (MD) simulations, Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) calculations, steered MD, and umbrella sampling simulations. Molecular docking of cocrystallized ligands papaverine and PFJ, along with a set of in-house synthesized molecules, suggested that molecule 3i haded the highest binding affinity, followed by 3h and 3j. Furthermore, the structural stability studies using MD and MM-PBSA indicated that the 3h and 3j formed stable complexes with PDE10A. The binding free energy of −240.642 kJ/mol and −201.406 kJ/mol was observed for 3h and 3j, respectively. However, the cocrystallized ligands papaverine and PFJ exhibited comparitively higher binding free energy values of −202.030 kJ/mol and −138.764 kJ/mol, respectively. Additionally, steered MD and umbrella sampling simulations provided conclusive evidence that the molecules 3h and 3j could be exploited as promising candidates to target PDE10A. Communicated by Ramaswamy H. Sarma

Oxalic/malonic acids as CH/C ₂ H ₃ carbon building blocks for the synthesis of 2-substituted and un-substituted benzazoles, quinazolines and quinazolinones.