Substituted-nicotinyl thiourea derivatives bearing pyrimidine moiety: synthesis and biological evaluation

A series of substituted-nicotinyl thiourea derivatives containing pyrimidine ring were synthesized in good to excellent yield using PEG-400 as solid-liquid phase transfer catalyst under ultrasonic irradiation. The structures of all newly synthesized compounds were elucidated and confirmed by IR, H-1 NMR and elemental analysis. The preliminary biological tests show that some of the target compounds present good inhibitory activities against the root and stalk of dicotyledon plants and are safe for monocotyledon plants.