A green and efficient protocol for synthesis of 1,4-dihydropyridine and polyhydroquinoline was achieved by the condensation of aldehydes, dimedone, ethylacetoacetate and ammonium acetate using environmentally benign Modified Eggshells (MES) as heterogeneous base catalyst. The promising features of reported methodology are use of green solvent system, high product yields, easy work up procedure, recycling of the catalyst and use of natural catalyst obtained from renewable resources. All synthesized compounds have been screened in vitro, against (G+) bacteria Staphylococcus aureus and (G- ) bacteria Escherichia coli as well as for antifungal activity against fungal strains Aspergillus flavus and Candida albicans using the agar well diffusion method.
