Abstract
Monoamine oxidase
(MAO) is a protein with a key function in the
catabolism of neuroamines in both central and peripheral parts of
the body. MAO-A and -B are two isozymes of this enzyme which have
emerged to be considered as a drug target for the treatment of neurodenerative
disorders such as Alzheimer’s disease (AD) and Parkinson’s
disease (PD). Isatin is an endogenous small fragment, reversible inhibitor
for MAO enzymes and is more selective for MAO-B than -A. Isatin is
responsible for increasing the dopamine level in the brain by the
inhibition of an MAO enzyme. The very few selective and reversible
inhibitors existing for MAO proteins and the intensity of neurological
diseases in humanity have opened a new door for researchers. Isatin
has a polypharmacological profile in medicinal chemistry, is a reversible
inhibitor for both the MAOs, and shows high selectivity potent inhibition
for MAO-B. In this review, we discuss isatins and their analogues
phthalide and phthalimide with structure–activity relationships
(SARs), and this comprehensive information accelerates the ideas for
design and development of a new class of MAO inhibitors for neurodegenerative
diseases.