Patent ID: 7259155

Claim:
A phosphonic acid diester compound represented by General Formula (1): wherein R 1 , R 2 , R 3 and R 4 are the same or different, and represent hydrogen, halogen, lower alkyl or lower alkoxy; R 5 is phenyl having on the phenyl ring 1–3 substituents selected from the group consisting of halogen-substituted lower alkyl, lower alkoxy, halogen-substituted lower alkoxy, phenoxy, benzyloxy, hydroxyl, halogen, nitro, lower alkylthio, di(lower alkyl)amino, lower alkanolyamino, pyrrolidinyl and phenyl, provided that when the substituent is a lower alkoxy group, R 5 is substituted with at least one other substituent; benzodioxolanyl, naphthyl, hydroxynaphthyl, thienyl optionally substituted with one member selected from the group consisting of lower alkyl, halogen and nitro, furyl optionally substituted with one member selected from the group consisting of lower alkyl, halogen, nitro and halophenyl, benzofuranyl, pyrrolyl optionally substituted with one lower alkyl, imidazolyl optionally substituted with one lower alkyl, or indolyl, provided that R 5 is not mono(lower alkoxy)phenyl; and R 6 is lower alkyl.