1,3,6,8,10-pentamethyl-1,3,6,8,10-pentazaspiro[4.5]decane-2,4,7,9-tetrone

methyl N-[4-[3-(methylcarbamoyl)-1,3-oxazolidin-2-yl]phenyl]carbamate

1-methyl-3-[4-(6-oxo-3-phenylpyridazin-1-yl)butyl]urea

1-methyl-3-[5-(6-oxo-3-phenylpyridazin-1-yl)pentyl]urea

1-methyl-3-[6-(6-oxo-3-phenylpyridazin-1-yl)hexyl]urea