a Nitroxides (nitroxyl radicals) hold a unique place in science due to their stable radical nature. We have recently reported the first design concept providing a general solution to the problem of designing and preparing mono cyclic α-hydrogen nitroxides. The initial works were limited to aryl derivatives. We now report a wider study showing that alkyl substituents may be employed as well. In addition, we report several additional examples of aryl substituents and reveal some of the strcutural limitations with regard to nitroxide stability as a function of the α-carbon substituent.