Abstract Deuterated analogues of C-phenyl N-tert-butyl nitrone (PBN) were synthesized to provide significant gains in spectral sensitivity and resolution in electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) applications. Three deuterated α-phenyl N-tert-butyl nitrones (PBNs) were prepared. EPR spectra of the corresponding radical spin adducts with the phenyl ring (PBN-d 5-R) or tert-butyl moiety ( ...