| abstract |
Compounds of formula I <IMAGE> (I) wherein R1 is C1-C4n-alkyl, isopropyl, s-butyl, cyclopentyl, cyclohexyl or alpha -methylbenzyl, R2 is C4-C18tert-alkyl or alpha , alpha -dimethylbenzyl, R3 is C1-C28alkyl, and R4 s methyl or ethyl, with the proviso that the -CHR3R4 group contains at least 4 carbon atoms, are suitable for stabilizing organic material which is susceptible to degradation induced by heat, oxidation or actinic light. |