Alpha-glucosidase and alpha-amylase inhibiting thiodiketopiperazines from the endophytic fungus Setosphaeria rostrata isolated from the medicinal plant Costus speciosus in Sri Lanka

Publication date: December 2017 Source:Phytochemistry Letters, Volume 22 Author(s): Ryan M. Centko, Pamoda B. Ratnaweera, Christina Tysoe, Stephen G. Withers, E. Dilip de Silva, Raymond J. Andersen Three new thiodiketopiperazine derivatives, rostratazine A (1), rostratazine B (2) and rostratazine C (3) along with exserohilone (4) and boydine A (5) were isolated and identified from the laboratory culture of Setosphaeria rostrata, an endophytic fungus obtained from the fresh asymptomatic leaf tissues of the medicinal plant Costus speciosus from Sri Lanka. The structures of compounds 1–3 were elucidated on the basis of detailed interpretation of 1D- and 2D- NMR data and comparison to known compounds. Compounds 1–5 were subjected to α-glucosidase inhibitory and porcine pancreatic alpha amylase inhibitory assays and 4 showed alpha–glucosidase inhibitory activity while 2 showed porcine pancreatic alpha amylase inhibitory activity. Graphical abstract
Source: Phytochemistry Letters - Category: Chemistry Source Type: research