Abstract: Multicyclic nitrone spin trapping compounds capable of forming stable free radical spin adducts are provided as well as methods for their synthesis. The multicyclic nitrone spin trapping compounds can be reacted with a free radical, such as a hydroxy or hydroperoxy radical, in solution to form a spin adduct which is stable and readily detectable by electron paramagnetic resonance (EPR) spectroscopy. The multicyclic nitrone spin traps can be used to detect free radicals in a sample such as a biological system. In one embodiment, the spin trapping compound, 1,3,3-trimethyl-6-azabicyclo-?3.2.1!oct-6-ene-N-oxide ("TRAZON") is provided, as well as methods for the synthesis of TRAZON and of modified forms of TRAZON. TRAZON can react with a wide range of different free radicals in solution to form free radical spin adducts which are readily detectable by EPR.