The reactions between excess 2,2-diphenyl-1-picrylhydrazyl (DPPH) and either 4-hydroxy-3,5-dimethoxybenzaldehyde (syringaldehyde, 1) or methyl 4-hydroxy-3,5-dimethoxybenzoate (methyl syringate, 2) afford different products from those obtained with the corresponding aroxide (3) of 1. In the former case (with the free phenols) the aryloxy (syringyl) group substitutes the 4-nitro group of DPPH, yielding dinitro products 7 and 8 (new stable free radicals) and 9 and 10 (corresponding hydrazines), whereas in the latter case (with the