| abstract |
A compound of formula (I)n in which R 1 and R 2 are e.g. hydrogen or methyl, R 1 is e.g. a groupn or a group RsX- with Rs being e.g. hydrogen, C 1 -C 18 -alkyl or C 3 -C 18 -alkenyl and X being e.g. -O-, -S- or NR 6 and R 6 is as defined for Rs, R 3 represents a 5-membered to 7-membered nitrogen containing heterocyclic group with the free valency on the nitrogen, n is an integer from 2 to 6, and R 4 is a nitrogen containing organic radical of a valency equal to n. n The compounds of formula (I) are particularly effective in stabilizing organic material against oxidative, thermal and/or light induced degradation. |