Background: Pictet-Spengler reactions is an irreplaceable part of cyclization reaction leading to the
formation of indispensable heterocyclic moieties including imidazole, benzoxazole, pyrrole, indole and others
having immense biological and chemical significance. Researchers have explored this reaction using different
types of catalysts and reactions conditions (including solvents, acids, etc.) to ensure the better selectivity, less
reaction time and high product yields. A total of five Pictet-Spenglerases have been discovered from various
sources including plants, animals, fungi, and microbes, and are responsible for the synthesis of various important
alkaloids of biological medicinal importance.
Objective: The present review is a strenuous effort to assemble information mainly focusing on synthetic as
well as biological Pictet-Spengler reactions catalysed by enzymes called Pictet-Spenglerase.
Conclusion: In the present review, the recent advances in the PS-mediated synthesis of diverse heterocycles
such as tetrahydroisoquinoline, tetrahydro-β-carbolines, tetrahydroimidazopyridines and other fused heterocycles
via chemical as well as enzymatic pathways have been covered. The compounds find their scope as medicinal
agents for the treatment of cancer, tuberculosis, bacterial infection, leishmanial, etc. The compilation is
expected to provide a mechanistic insight to chemists to enhance the reaction condition, yields and another parameter
to ensure the safe and inexpensive reaction conditions considering the “Green-Concept” of chemistry.