1,4-dibutoxy-6-methylindolo[3,2-b]quinoxaline

4,7-dibutoxy-1'-methylspiro(2H-benzimidazole-2,3'-indolin)-2'-one

4,7-dibutoxy-1'-methylspiro(benzimidazoline-2,3'-indolin)-2'-one

2,2',5,5'-tetrabutoxy-6,6'-dinitroazobenzene

5,8-dibutoxy-1,4-dihydro-quinoxaline-2,3-dione