Title:Recent Updates on Pyrazoline Derivatives as Promising Candidates for Neuropsychiatric and Neurodegenerative Disorders
Volume: 21
Issue: 30
Author(s): T. M. Rangarajan*Bijo Mathew*
Affiliation:
- Department of Chemistry, Sri Venkateswara College, University of Delhi, New Delhi-110021,India
- Department of Pharmaceutical Chemistry, Amrita School of Pharmacy, Amrita Vishwa Vidyapeetham, AIMS Health Sciences Campus, Kochi-682 041,India
Keywords:
Pyrazolines, MAO-A, Chalcones, MAO-B, SAR, Hydrazines.
Abstract: Pyrazolines are five-membered heterocyclic compounds containing two nitrogen atoms
that represent a privileged scaffold for various bioactive compounds with diverse pharmacological
activities. Chalcones and hydrazine derivatives are excellent precursors for pyrazolines, which provide
easy access for fabricating the pyrazoline ring at N1, C3 and C5 positions that give rise to a wide
range of pyrazoline designs. In addition, this method institutes a new asymmetric center at C5 position
and extent of the conjugation between phenyl group at C3 position to N1 that could greatly enhance
the physicochemical and pharmacological properties towards the target enzymes and hence
they are reported to have a wide spectrum of biological activities such as anti-cancer, antiinflammatory,
etc. Most importantly, they have remarkable effects on the central nervous system
(CNS). Several reports show that the pyrazoline derivatives have a 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 are generally
potential and more selective inhibitors towards MAO-B isoform whereas pyrazolines derived from
chalcones mostly turned into selective inhibitors of MAO-A isoform may be due to the presence of
two nitrogen heteroatoms. Therefore, these two derivatives have received much attention from medicinal
chemists as they could solve entire CNS-related issues; however pyrazolines have not been studied
as much as chalcones. Our group already documented the importance of pyrazolines towards
MAO-A inhibition in 2013. With their growing importance, several studies on pyrazolines have constantly
been reported for their MAO inhibitions. Therefore, in this review, we report up-to-date developments
(after 2014) on pyrazolines as potential MAO inhibitors.