CA2616512A1 — Novel benzimidazole (thio) carbamates with antiparasitic activity and the synthesis thereof

USPTO Abstract

The present invention is concerned with novel benzimidazole (thio)carbamates with antiparasitic activity. The present invention provides compounds of the following general formula (I) wherein X1 and X2 are O or S, wherein at least one of X1 and X2 is O, Y1 and Y2 are O or S, wherein at least one of Y1 and Y2 is O, R1 is alkyl of 1-4 carbon atoms, R2, R3 and R4 are independently of each other hydrogen, or a cation, R5 and R6 may both independently be hydrogen or halogen or alkyl having from 1-8 carbon atoms, or -OR7, wherein R7 is alkyl having from 1-8 carbon atoms, or -SR8, wherein R8 may be alkyl having from 1-8 carbon atoms, or aryl, or -CO-R9, wherein R9 is alkyl having from 1-8 carbon atoms, cycloalkyl having from 3-6 carbon atoms, or R9 is aryl, or -OSO2-Ar, wherein Ar is aryl, or -S(O)R10, wherein R10 is alkyl having from 1-8 carbon atoms, or wherein R10 is aryl. The compounds of the invention are highly soluble and stable in water. Moreover, it has been found that the compounds according to the invention are stable for over 8 hours at pH 5 and at pH 9, which are the lower and upper pH limits at which compounds should be stable for over 8 hours in order to be suitable for drinking water application. The compounds of the present invention have excellent antiparasitic, and especially anthelmintic activity in vivo, which is comparable to the state of the art, water insoluble, benzimidazole carbamates such as albendazole and fenbendazole.