A detailed analysis of Prangos pabularia Lindl. (Apiaceae) fruit oil was performed by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Bicyclogermacrene (21%), (Z)-beta-ocimene (19%), alpha-humulene (8%), alpha-pinene (8%) and spathulenol (6%) were the main constituents of the oil. One compound with 1.8% at RI 3420 remained unidentified or tentatively identified as suberosin from the Wiley GC-MS Library. The assumed compound, suberosin was synthesized in two steps and its structure was confirmed by 1D NMR and GC-MS analyses. As part of our continued research to discover new chemicals for use in mosquito control agents as repellents and larvicides, suberosin and its parent compound coumarin were investigated for the mosquito biting deterrent and larvicidal activity against Aedes aegypti. Both suberosin and coumarin showed biting deterrent activity but the activity was lower than the positive control, DEET (N,N-diethyl-3-methylbenzamide). In larval bioassays, suberosin with LC50 value of 8.1 ppm was significantly more toxic than coumarin (LC50 = 49.6 ppm) at 24-h post treatment. These results indicate that suberosin may be useful for use as mosquito larvicidal agent.