**1. Introduction**

The name pyridine is derived from the Greek word and is a combination of two words: pyr means fire and idine is used for aromatic bases [1]. It is nitrogen-containing heterocycle [2], six-membered and aromatic, and it plays a vital role in the field of medicinal chemistry [3]. Cancer is a group of more than 100 different diseases. It can progress almost anywhere in the body. The causes of cancers are host variables such as genetics, epigenetics, microbiome, age, gender, metabolic state, inflammatory state, and immune function [4]. Environmental factors such as food contamination, viruses, UV radiation, carcinogens from the environment, and diet/lifestyle factors such as nutrients, energy consumption, phytochemicals, other food ingredients, alcohol, physical activity, and smoking [5]. Some of the derivatives of pyridine nucleus containing molecules that are potential drug candidates are streptonigrin, streptonigrone, and lavendamycin, which were reported in the literature [6]. Some of the reported pyridine molecules are selective toward topoisomerase inhibitors [7]. Some of the pyridine-conjugated derivatives were PIM-1 kinase inhibitors [8], human carbonic anhydrase inhibitors [9], proto-oncogene tyrosine-protein kinase (ROS) [10],

ALK/ROS1 dual inhibitors, receptor tyrosine kinase (RTK) c-Met, epidermal growth factor receptor [11], EGFR and HER-2 kinase inhibitors, cyclin-dependent kinase (CDK) inhibitors [12], VEGFR-2 inhibitors [12], topoisomerases, phosphoinositide 3-kinase, maternal embryonic leucine zipper kinase (MELK), NF-κB inhibitors [13], etc. Considering all this information, exploration of these heterocycles is very important for the development of potential anticancer drug candidates. Hence, we covered all the reports related to the pyridine moiety in this book chapter.
