Pangelin, an antimycobacterial coumarin from Ducrosia anethifolia.

The aerial parts of Ducrosia anethifolia afforded the monoterpene glucoside 8-debenzoylpaeoniflorin ( 1) and the prenylated furanocoumarin pangelin [5-[2"( R)-hydroxy-3"-methyl-3"-butenyloxy]furocoumarin] ( 2). Their structures were determined by extensive 1- and 2-dimensional NMR studies. Compound 2 demonstrated activity against a panel of fast growing mycobacteria, namely Mycobacterium fortuitum, M. aurum, M. phlei and M. smegmatis and minimum inhibitory concentration (MIC) values ranged from 64 - 128 microg/mL. Whilst compounds 1 and 2 have previously been reported as an antihyperglycaemic component from Paeonia lactiflora, and as a constituent of Angelica pancici, respectively, this is the first report of the full (1)H- and (13)C-NMR data for these natural products.