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Mutations in multi‐domain leucine‐rich repeat kinase 2 (LRRK2) have been an interest to researchers as these mutations are associated with Parkinson's disease. G2019S mutation in LRRK2 kinase domain leads to the formation of  additional hydrogen bonds by S2019 which results in stabilization of the active state of the kinase, thereby increasing kinase activity. Two additional hydrogen bonds of S2019 are reported separately. Here, a mechanistic picture of the formation of additional hydrogen bonds of  S2019 with Q1919 (also with E1920) was presented using ‘active’ Roco4 kinase as a homology model and its relation with the stabilization of the ‘active’ G2019S LRRK2 kinase. A conformational‐flipping of residue Q1919 was found which helped to form stable hydrogen bond with S2019 and made ‘active’ state more stable in G2019S LRRK2. Two different states were found within ‘active’ kinase with respect to the conformational change (flipping) in Q1919. Two doubly‐mutated systems, G2019S/Q1919A and G2019S/E1920K, were studied separately to check the effect of Q1919 and E1920. For both cases, the stable S2 state was not formed, leads to a decrease in kinase activity. These results that both the additional hydrogen bonds of S2019 (with Q1919 and E1920) were necessary to stabilize the active G2019S LRRK2.

A trinuclear copper complex [Cu 3 (napxshz) 2 (phen) 2 ] has been synthesised using a tribasic naproxen-appended ligand [propanoyl) benzohydrazide] and 1,10-phenanthroline. The complex was characterised by different spectroscopic methods such as Fouriertransform infrared (FT-IR), ultraviolet-visible (UV-Vis) and electrospray ionisation (ESI)-mass spectroscopy. The solid-state structure of the ligand and complex 1 was established by single-crystal X-ray diffraction analysis. The interaction of the complex and the ligand with DNA was investigated by UV-visible spectroscopy and fluorometric titrations. The calculated binding constants (K b ) of the complex and the ligand with ct-DNA show that the complex has a higher binding affinity than the ligand H 3 napxshz. Quantum chemical calculations were performed to understand the structural aspects of the complex and its interactions with DNA. The molecular docking study reveals the interaction between DNA, and the complex is in intercalative mode.

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