4-Dihydropyridine Synthesis Lab Report

Experiment 15B was conducted in order to learn about the Hantzsch 1,4-Dihydropyridine synthesis mechanism. Furthermore, this lab will give students a better understanding of the terms pharmacophore and a privileged structure. In order for this reaction to occur an aldehyde, ammonia, and two equivalents of a B-ketoester go through a one-pot cyclocondensation reaction. After 1,4-dihydropyridine is formed, it is then oxidized to form its pyridine derivative. Alcohol or Acetic acid is then used as a refluxing solvent for this compound. This compound has been found to have many uses including the treatment of cardiovascular disease and Ca2+ channel blockers. These dihydropyridines are also powerful antioxidants. In this lab, 430 mg of ammonium acetate, 960 microliters of ethyl acetoacetate, and 36% wt. aqueous formaldehyde were added to a 10 mL round bottom flask and allowed to heat to 80°C with constant stirring. After 10 minutes, a solid and wet product was formed. Vacuum filtration was then used to filter the product. Recrystallization methods were then completed using 95% ethanol in order to isolate the pure …show more content…
The major factor that allows calcium channel blockers to be effective are ethyl groups at the 3 and 5 position, and cyclic substituents on the 4 position. Furthermore, it was found that electronegativity has no effect on blocking ability; as a result, electron donating and withdrawing groups placed on cyclic substituents don't have an effect. However, certain functional groups including bulky groups push substituents to want a position perpendicular to the dihydropyridine ring plane (Love, B.; Goodman, M. M.; Snader, K.M.; Tedeschi, R. Macko, E. J. Med. Chem. 1974, 17, 956-965). The products in this lab are ineffective because they lack an aryl substituent in the 4 position, therefor have a low