Isoquinoline (ISOQ) is a heterocyclic aromatic organic compound composed of a benzene ring fused to a pyridine ring, referred to as benzopyridines. The chemical formula is C9H7N with a molar mass of 129.162 g/mol. This ISOQ ring derives from the natural aromatic amino acid tyrosine. It is weak alkaline in nature but is more basic than quinoline. It appears as a yellowish oily liquid, having an unpleasant odour, hygroscopic when solid, has a density of 1.099 g/cm3, a melting point of 26__ampersandsigndeg;C to 28__ampersandsigndeg;C (79__ampersandsigndeg;F to 82__ampersandsigndeg;F), the boiling point of 242__ampersandsigndeg;C (468__ampersandsigndeg;F), and dipole moment of 2.49. In the preparation of this review article, a widespread examination of the published literature in varied pharmaceutical and medical databases such as PubMed, Google Scholar, etc. was fruitfully carried out and categorized consequently. The imperative review revealed the less known biological (anti-fungal, anti-Parkinsonism, anti-tubercular, anti-tumour, anti-glaucoma, anti-Alzheimer__ampersandsignrsquo;s disease, anti-viral, anti-bacterial, anti-diabetic, anti-malarial, etc.) potentials of ISOQ (an important class of chemical compounds) and their synthetic derivatives. This knowledge will serve as a ready reference for the global researchers and will be very helpful or inspiring for the medicinal chemists or associated investigators in developing novel low-molecular-weight (LMW) inhibitors for pharmacotherapeutic applications.