Patent ID: 7943661

Claim:
A compound of formula (I) in which: X 1 is a halogen, R1 or -G1-R1, X 2 is hydrogen, hydroxy or an unsubstituted alkyloxy, X 3 is —R3 or -G3-R3, X 4 is a —R4 or -G4-R4, X 5 is —R5 or -G5-R5, X 6 is oxygen, R1, R3 and R5, which are the same or different, are an unsubstituted alkyl having from one to seven carbon atoms, R4 is an alkyl having from one to seven carbon atoms substituted by a group 1 substituent, G1, G3, G4, and G5, which are the same or different, are oxygen or sulphur wherein at least one of X 1 , X 3 , X 4 and X 5 is G1R1, G3R3, G4R4 and G5R5, respectively, said group 1 substituent being selected from the group consisting of —COOR 6 and —CONR 6 R 7 , wherein R 6 and R 7 , which are the same or different, are hydrogen or an unsubstituted alkyl having from one to seven carbon atoms, or an optical isomer, a geometric isomer, a racemate, a tautomer, a salt or mixtures thereof.