A New Coumarin from the Stems of Pterocarpus indicus

The chemical investigation of the crude ethyl acetate extract from Pterocarpus indicus stems led to isolation of a new coumarin, indicusane (1), together with eleven known compounds (2-12). To the best of our knowledge, all isolated coumarins (1-12) are reported for the first time from this plant. Their structures were identified on the basic of spectroscopic data (NMR, MS and ECD) as well as a chemical reaction (Mosher's method). In addition, all isolates were also evaluated for their cholinesterase (ChEs) inhibitory activities, in which only compound 4 exhibited the moderate activity toward AChE and BChE.