| 摘要 |
<p>Cpds. (I) of formula:- where R is phenyl opt. substd. by 1 or 2 Cl atoms, F, -CF3, (di)lower alkoxy, (di)lower alkyl, cyclohexyl or cyclopentyl; R1 = H or lower alkyl; R2 = H, lower alkyl lower alkyl carboxylate ester gp., or a Na, Ca or NH4+ carboxylate gp., and X = lower alkyl carboxylate ester, -COOH, or an opt. substd. N-lower alkyl, N,N-dilower alkyl; N-aryl, N-aralkyl- or N-heterocyclic-substd. carboxamide gp., or a Na, Ca, or NH4+ carboxylate gp.; provided that when R2 = lower alkyl carboxylate ester or salt gp., X = R2 (I) are useful as UV absorbers in sunscreening compositions, and in plastics and resins, e.g. polystyrene etc.</p> |
