A description is given of compounds of the formula Iin whichR1 is C1-C18alkyl C5-C12cycloalkyl C3-C6alkenyl phenyl C1-C18alkyl which is substituted by phenyl, OH, C1-C18alkoxy, C5-C12cycloalkoxy, C3-C18alkenyloxy, halogen, -COOH, -COOR4, -O-CO-R5, -O-CO-O-R6, -CO-NH2, -CO-NHR7, -CO-N(R7)(R8), CN, NH2, NHR7, -N(R7)(R8), -NH-CO-R5, phenoxy, C1-C18alkyl-substituted phenoxy, phenyl-C1-C4alkoxy, C6-C15bicycloalkoxy, C6-C15bicycloalkylalkoxy, C6-C15bicycloalkenylalkoxy, or C6-C15tricycloalkoxy C5-C12cycloalkyl which is substituted by OH, C1-C4alkyl, C2-C6alkenyl or -O-CO-R5 glycidyl -CO-R9 or -SO2-R10 or R1 is C3-C50alkyl which is interrupted by one or more oxygen atoms and/or substituted by OH, phenoxy or C7-C18alkylphenoxyor R1 denotes the specific polymerizable radicals indicated in claim 1R2 is C6-C18alky1 C2-C6alkenyl phenyl C7-C11phenylalkyl COOR4 CN NH-CO-R5 halogen trifluoromethyl -O-R3R3 embraces the definitions given for R1the radicals R11 independently of one another are H C1-C18alkyl C3-C6alkenyl phenyl C7-C11phenylalkyl halogen or C1-C18alkoxy, and the remaining radicals embrace the definitions given in claim 1, at least one of the radicals R1, R2 and R11 containing 4 or more carbon atoms. The novel compounds are effective as stabilizers for organic material against the damaging effect of light, oxygen and heat they are also suitable for use in skin or hair protection preparations.
