The magnetic properties of 4-methacrylamide-, 4-acrylamide-, and 4-isobutyramide-2,2,6,6-tetramethyl-1-piperidinyloxyl (MATMP, AATMP, and SMATMP (saturated MATMP), respectively) were studied. The magnetic susceptibility, magnetization, and molar heat capacity of MATMP show that the crystal has one-dimensional ferromagnetic coupling just like as the case of 4-methacryloyloxy-2,2,6,6-tetramethyl-1-piperidinyloxyl (MOTMP). On the other hand, both AATMP, where hydrogen atom is substituted for a methyl group at alpha-position, and SMATMP, where the C=C double bond is saturated, show an antiferromagnetic coupling between nitroxyl radicals. Magnetic interaction of AATMP was stronger than that of SMATMP. The difference of magnetic properties between MATMP and AATMP are similar to that between MOTMP and 4-acryloyloxy-2,2,6,6-tetramethyl-1-piperidinyloxyl (AOTMP). The difference in crystal packing between MATMP and AATMP was similar to that between MOTMP and AOTMP. The crystal packing of SMATMP was similar to those of AATMP and AOTMP.