Used primarily in organic synthesis, it serves as a key reagent for introducing methyl groups into molecules, particularly in the preparation of methylated derivatives of amines and amino acids. It is also employed in the synthesis of pharmaceuticals, where it aids in the modification of compounds to enhance their biological activity or stability. Additionally, it finds application in the production of agrochemicals, contributing to the development of pesticides and herbicides. Its role in the creation of modified peptides and proteins is significant for research in biochemistry and molecular biology.