N-[(Z)-(3-butyl-4-oxo-1,3-thiazolidin-2-ylidene)amino]-2-(1,3-dimethyl-2,6-dioxopurin-7-yl)acetamide

(2-ethoxy-2-oxoethyl) 2-cyanoacetate

N-[(Z)-[3-(4-bromophenyl)-4-oxo-1,3-thiazolidin-2-ylidene]amino]-2-(1,3-dimethyl-2,6-dioxopurin-7-yl)acetamide

6-ethoxy-4,6-dioxohexanoate

ethyl 2-[4-(trifluoromethoxy)phenoxy]acetate