Chemistry is no doubt a vast subject which focuses on various molecules either inorganic or organic. These molecules are classified into laboratory chemicals, biomolecules, pharmaceuticals, warfare agents, domestic chemicals, industrial chemicals, cosmetics, dyes and so many ingredients. All the molecules are structurally frame worked from Mendeleev¿s periodic table elements which are again sub-classified into metals and non metals which joins with each other by catenation property by either electrovalent bond, coordinate bond and covalent bond by hybridization rule of s, p, d & f atomic orbital theory. Each and every element has its original chemical property which forms the compound having individual characteristics These individual chemicals react with other chemicals either in-vivo (inside the living system), in-vitro (outside the living system), in-situ (inside the reaction vessel) and in-silico (inside the computational software) to develop the new entity through the functional group attached with it which may of single step or multi step synthesis or biosynthesis. Chemistry is a playground of functional groups focuses on this book chapter along with the Nobel Laureates.

Eminent scholar cum researcher Prof. Dr. Dhrubo Jyoti Sen is at present working as a Professor of Pharmaceutical & Medicinal chemistry in School of Pharmacy, Techno India University, Kolkata, West Bengal, India is working in academic field from more than two decades and has published more than 600 research/review papers in peer reviewed journals.