A greener path to antimicrobials
doi:10.1038/nindia.2017.79 Published online 10 July 2017
Even reactions that have been in use for more than a century can be improved upon, scientists have shown. Researchers working at Sardar Patel University in Gujarat have found a clean and efficient method of synthesis for a series of bioactive Hantzsch 1, 4-dihydropyridine derivatives1, named for the German chemist who pioneered the synthesis of substituted pyridines.
1, 4-dihydropyridines are chemicals that block calcium channels, and whose pharmacological activity ranges from anti-hypertensive to antimicrobial. Recent efforts in green chemistry have centered around using one-pot multicomponent reactions to create these molecules, but this approach has disadvantages, from long reaction times, tedious preparation, and reliance on expensive catalysts.
A group led by H. M. Patel reports a solvent-free, room temperature synthesis that uses catalytic ceric ammonium nitrate of six 1, 4-dihydropyrdine derivatives.
The group assessed the antimicrobial activity of these compounds in Gram positive and Gram negative bacteria, and found that five were more potent than ampicillin. Likewise, in yeast, one compound was more potent than griseofulvin. The group selected three compounds from the series for anticancer screening at the National Cancer Institute at the National Institutes of Health in the United States.
1. Sharma, M.G. et al. Green approach for synthesis of bioactive Hantzsch 1, 4-dihydropyridine derivatives based on thiopene moiety via multicomponent reaction. R. Soc. Open Sci. (2017). doi: 10.1098/rsos.170006