The present review focuses on the patented synthetic methods and numerous pharmaceutical applications of
1,4-dihydropyridines. They were originally prepared by the Hantzsch multicomponent reaction, but nowadays there are
several new methods. They have improved reaction yield and have reduced the risks of contaminating the environment.
These improvements were achieved through the use of different catalytic systems, a variety of reaction solvents, and also
some reactions were carried out without either catalyst or reaction solvent.