Parallel liquid-phase synthesis of 5-(1H-4-pyrazolyl)-[1,2,4]oxadiazole libraries.

Combinatorial libraries of substituted 3-(methylthio)-5-(amino)-4-([1,2,4]oxadiazol-5-yl)-1H-pyrazoles 6, 10, 13, 15 (395 members, yields 32-87%), 4-([1,2,4]oxadiazol-5-yl)-1H-3,5-pyrazolediamines 8, 11 (571 members, yields 25-83%), 2-(methylthio)-3-([1,2,4]oxadiazol-5-yl)pyrazolo[1,5-a]pyrimidin-7(4H)-ones 17 (85 members, yields 56-95%), and 2-(amino)-3-([1,2,4]oxadiazol-5-yl)pyrazolo[1,5-a]pyrimidin-7(4H)-ones 18 (110 members, yields 56-95%) were synthesized by the parallel liquid-phase synthesis method.