Related Articles Diverse chemical space of indoleamine 2 3 dioxygenase 1 Ido1 inhibitors Eur J Med Chem 2020 Dec 02 211 113071 Authors Singh R Salunke DB Abstract Indoleamine 2 3 dioxygenase 1 IDO1 catalyses the first and rate limiting step of kynurenine pathway accounting for the major contributor of L Tryptophan degradation The Kynurenine metabolites are identified as essential cofactors antagonists neurotoxins immunomodulators antioxidants as well as carcinogens The catalytic active site of IDO1 enzyme consists of hydrophobic Pocket A positioned in the distal heme site and remains connected to a second hydrophobic Pocket B towards the entrance of the active site IDO1 enzyme also relates directly to the modulation of the innate and adaptive immune system Various studies proved that the over expression of IDO1 enzyme play a predominant role in the escape of immunity during cancer progression Recently there has been considerable interest in evaluating the potential of IDO1 inhibitors to mobilize the body s immune system against solid tumours In the last two decades enormous attempts to advance new IDO1 inhibitors are on going both in pharmaceutical industries and in academia which resulted in the discovery of a diverse range of selective and potent IDO1 inhibitors The IDO1 inhibitors have therapeutic utility in various diseases and in the near future it may have utility in the treatment of COVID 19 Despite various reviews on IDO1 inhibitors in last five years none of the reviews provide a complete overview of diverse chemical space including naturally occurring and synthetic IDO1 inhibitors with detailed structure activity relationship studies The present work provides a complete overview on the IDO1 inhibitors known in the literature so far along with the Structure Activity Relationship SAR in each class of compounds PMID 33341650 PubMed as supplied by publisher