PURPOSE: To obtain a novel pyrimidine derivative which is useful as a selective herbicide for plowed land, paddy field and untilled lands because it show selectivity to important crop plants and excellent herbicidal effect on a variety of weeds with reduced doses.
CONSTITUTION: A compound of the formula I [Ra is H, halogen, 1 to 6C alkoxy, 1 to 6C (halo)alkyl; Rb is phenyl, benzyl pyridyl, thienyl, funyl all of which may be arbitrarily substituted with substituents such as 1 to 4C alkyl, halogen or the like; Z is N, CH; Rc is SR1, OR2, N(R3)R4 (R1 to R4 are H, 1 to 6C alkyl, 1 to 6C alkenyl, 1 to 6C alkinyl where R3 and R4 may form a 3 to 7-membered ring together with bound N atom and the ring may include O, N, S atoms)], for example, 5-[2-(4-fluorophethyl)-6-methylthio-4-pyrimidyl]-4-triflurormethyl- pyrimidine. The compound of the formula I in which Rc is SR1 and Z is N, namely the compound of formula IV, is obtained by subjecting a 5- acylpyrimidine derivative of formula II as a starting substance to the reaction path way given in the Figure.
KONDO YASUO
KUDO YOSHIHIRO
NAWAMAKI TSUTOMU
WATANABE SHIGEOMI
ISHIKAWA KIMIHIRO
ITO YOICHI
