Compounds of the general formula I
wherein
R1 and R2each independently are C2-C18 alkyl or C5-C7 cycloalkyl, or C2-C18 alkyl in which at least one methylene group is replaced by oxygen;
R3is hydrogen, C1-C18 alkyl or C2-C18 alkyl in which at least one methylene group is replaced by oxygen, or is C1-C18 alkyl carbonyl, C3-C18 alkenyl, C3-C18 alkynyl or a group YS;
R4is hydrogen, C1-C8 alkyl or a group OR3;
Yis a linker group;
Sis a silane-, an oligosiloxane- or a polysiloxane-moiety.
are effective in absorbing ultra violet radiation and can be used as sunscreen agents.
通式 I 的化合物
其中
R1和R2各自独立地为C2-C18烷基或C5-C7环烷基,或其中至少一个亚甲基被氧取代的C2-C18烷基;
R3 是氢、C1-C18 烷基或其中至少一个亚甲基被氧取代的 C2-C18 烷基,或 C1-C18 烷基羰基、C3-C18 烯基、C3-C18 炔基或基团 YS;
R4 是氢、C1-C8 烷基或基团 OR3;
Y 是连接基团;
S 是
硅烷、低聚
硅氧烷或聚
硅氧烷分子。
可有效吸收紫外线辐射,可用作防晒剂。