Background A series of coumarin-indole hybrids was synthesized as the new α-glucosidase inhibitors. The title hybrids were considered as α-glucosidase inhibitors because had two active pharmacophores against α-glucosidase: coumarin and indole. Methods The thirteen various derivatives 4a–m were synthesized, purified, and fully characterized. These compounds were evaluated against α-glucosidase in vitro and in silico. In silico pharmacokinetic studies of the most potent compounds were also performed. Results Most of the title compounds exhibited high anti-α-glucosidase activity in comparison to standard drug acarbose. In particular, the phenoxy derivative 4d namely 3-((1H-indol-3-yl)(3-phenoxyphenyl)methyl)-4-hydroxy-2H-chromen-2-one showed promising activity. This compound is a competitive inhibitor against α-glucosidase and showed the lowest binding energy at the α-glucosidase active site in comparison to other potent synthesized compounds and acarbose. Conclusion Compound 4d can be a lead compound for further structural development to obtain effective and potent α-glucosidase inhibitors.

Background A new series of coumarin-indole hybrids was designed and synthesized as novel anti-diabetic agents through inhibition of α-glucosidase, which is an important anti-diabetic target. The title hybrids were designed based on hybridization of two active pharmacophors against α-glucosidase: coumarin and indole. Methods The thirteen various derivatives 4a-m were synthesized, purified, and fully characterized. These compounds were evaluated against α-glucosidase in vitro and in silico. In silico pharmacokinetic study of the most potent compounds was also performed. Results Most of the title compounds exhibited high anti-α-glucosidase activity in comparison to standard drug acarbose. In particular, the phenoxy derivative 4d namely 3-((1H-indol-3-yl)(3-phenoxyphenyl)methyl)-4-hydroxy-2H-chromen-2-one showed promising activity. This compound is a competitive inhibitor into α-glucosidase and showed the lowest binding energy at α-glucosidase active site in comparison to other potent newly synthesized compounds and acarbose. Conclusion Compound 4d can be a lead compound for further structural development to obtain an effective and potent α-glucosidase inhibitor.