Synthesis and Antifungal Activity of Some Novel Coumarin-Amino Acid Conjugates

A series of novel coumarin-amino acid conjugates was synthesized and structural characterization was done by various spectroscopic methods. All the conjugates were screened for their antifungal activity against five fungal strains namely T. rubrum, A. niger, A. fumigatus, A. flavus and C. albicans by two-fold serial microdilution method. Some of them showed significant activity with MIC values in the range of 6.25-25 mu g/mL. Notably, compound 5 e showed potential antifungal effect against three tested strains with MIC's in the range of 6.25-12.5 mu g/mL. The molecular docking studies showed that some conjugates possessed good binding affinity with the modelled receptor of integrin-like protein of Cryptococcus neoformans var. grubii. Compounds 5 d and 5 e also exhibited good binding efficiency with the Candida spp. cell wall associated proteins in in vitro binding assay. Additionally, in silico physicochemical parameters such as lipophilicity and pharmacokinetic properties such as absorption, distribution, metabolism, and excretion (ADME) of the synthesized compounds were also evaluated.