The present Invention relates to imidazole Derivatives of the General formula (i) in donder1 means Lower alkyl, halogen, alkoxy or lower alkyl; R2, mean hidroxialquilo Lower, Lower, lower or alkoxyalkyl Esters; R3 is Hydrogen, Lower alkyl, hidroxialquilo in Q, means less than or alkoxyalkyl Esters; or - n or - ch = =; R4 is a group of the formula IIA or IIB where, X,Y and Z are, independently, or - ch = n =; and where only one of the X or y, can be a nitrogen Atom; R5 and R6 are, independently Hydrogen, Lower alkyl, hidroxialquilo alkoxyalkyl Esters Lower, Lower, - (CH2) M - (CO) or lower alkyl, M - S - (CH2) (OR) 2 Lower alkyl, - (CH2) M - C (o) - Nr 'r', where M = 0 - 3 and R 'and R' 'are, in an independent manner.Hydrogen or lower alkyl, and pharmaceutically acceptable salts thereof. It has now been found, in a surprising Way, the fact that the compounds of the General formula I are antagonists of metabotropic glutamate receptors. These can be used in the Treatment or prevention of disorders mediated by the receptor mGluR5.La presente invención, se refiere a derivados de imidazol de la fórmula general (I)en dondeR1, significa halógeno, alquilo inferior ó alcoxi inferior; R2, significa alquilo inferior, hidroxialquilo inferior, o alcoxialquilo inferior; R3, significa hidrógeno, alquilo inferior, hidroxialquilo inferior o alcoxialquilo; Q, significa ó -N= ó -CH=;R4, es un grupo de la formula IIa ó IIb en donde, X, Y y Z, son, de una forma independiente, -CH= ó -N=; y en donde, solamente una de entre las X ó Y, puede ser un átomo de nitrógeno;R5 y R6 son, de una forma independiente, hidrógeno, alquilo inferior, hidroxialquilo inferior, alcoxialquilo inferior, -(CH2)m-(CO)O-alquilo inferior, -(CH2)m-S(O)2-alquilo inferior, -(CH2)m-C(O)-NR'R'', y en donde, m = 0 - 3 y R' y R'' son, de una forma independiente, hidrógeno ó alquilo inferior, así como a las sales farmacéuticamente aceptables de éstos. Se ha encontrado ahora, de una forma sorprendente, el hecho de que, los