Synthesis and Biological Evaluation of Novel Coumarins with tert-Butyl and Terpene Substituents.

Coumarins with terpene and tert-butyl substituents were synthesized via Pechmann condensation reaction. New derivatives were investigated in different model system for the exhibition of antioxidant, radical scavenging and membrane-protective activities. It has been found that 4-methylcoumarin derivatives with monoterpene moieties exhibit high antioxidant activities. The most active and promising for further investigations is 5-hydroxy-6,8-diisobornyl-4-methylcoumarin, containing two isobornyl substituents on the benzopyran ring.