Recent Updates on Pyrazolines Derivatives as Promising Candidates for Neuropsychiartic and Neurodegenerative disorders.

Pyrazolines are five membered heterocyclic compounds containing two nitrogen atoms represent a privilege scaffold for various bioactive compounds with diverse pharmacological activities. Chalcones and hydrazine derivatives are excellent precursors for pyrazoline, which provide sites for manipulation at N1, 3- and 5-positions of pyrazoline which results a wide range of pyrazoline structures. This method creates a new asymmetric centre at 5-position and extent of conjugation from phenyl group to N1-nitrogen (Fig. 2) that could greatly enhances the physiochemical and pharmacological properties towards target enzymes and hence they are reported to be having wide spectrum of biological activities such as anti-cancer, anti-inflammatory, etc. Most importantly, they have remarkable effect on central nervous systems (CNS). Several reports show that the pyrazoline derivatives have significant inhibitory effect towards the monoamine oxidase enzymes (MAOs) which are known to be responsible for neurodegenerative disorders. These enzymes have two isoforms namely MAO-A and MAO-B which are, in particular, responsible for psychiatric and neurological disorders respectively. Chalcones, generally, are potential and more selective towards MAO-B inhibitions whereas pyrazolines derived from chalcones turned into selective towards MAO-A inhibitions due to maybe the presence of two nitrogen heteroatoms. Therefore, these two derivatives are received much attention among the medicinal chemists as they could solve entire CNS related issues; however pyrazolines are not studied as much as chalcones. Our group has already documented the importance of pyrazolines towards MAO-A inhibition in 2013. With their growing importance many studies on pyrazolines are being carried out constantly for MAO-A inhibition. Therefore, in the present work, we report an update on pyrazolines as potential MAOs inhibitors that are reported during 2014 to date.