Synthesis and antioxidative activity of 2-substituted phenyl-5-(3'-indolyl)-oxazole derivatives

Aim: To study the synthesis of 5-(3'-indolyl)-oxazoles and their antioxidative activity.

Methods: The amides were prepared from tryptophan and different acid derivatives by the catalytic dehydration of dicyclohexyl carbodiimide (DCC). The characteristic heterocyclic ring system of 5-(3'-indolyl)-oxazoles was constructed by oxidative cyclization of amide, using dicholorodicyanoquinone (DDQ). Their antioxidative activity in vitro was tested using DPPH system.

Results: Eleven 2-substituted phenyl-5-(3'-indolyl)-oxazoles were prepared, the compounds 21 and 22 have shown antioxidative activity 3-4 times stronger than that of Vit E, and the compound 29 showed antioxidative activity almost as same as Vit E.

Conclusion: Three 5-(3'-indoyl)-oxazole compounds synthesized showed potent antioxidative effect and they would be a good antioxidants.