The cationic dye may be chosen from azo dyes, azomethine dyes, methine dyes and xanthene dyes.
优选地，阳离子染料选自偶氮染料、偶氮甲碱染料、次甲基染料和？吨染料。
2
Methyl 9-hydroxyl-9-xanthene carboxyate which is an important intermediate of xanthene anticholiergic drugs was easily synthesized from methyl 9-xanthene carboxyate.
羟基-9-呫吨羧酸甲酯是合成呫吨类抗胆碱能药物的一种重要的中间体。
3
In the present paper, a series of xanthene-2-carboxylic acids and xanthone-2-carboxylic acids with electron withdrawing groups on the 7-position had been synthesized.