Abstract: This invention is related to substituted semicarbazides represented by Formula (I) or a pharmaceutically acceptable salt or prodrug thereof, wherein: R1 and R2 are independently hydrogen, alkyl, cycloalkyl, alkenyl, alkynyl, haloalkyl, aryl, aminoalkyl, hydroxyalkyl, alkoxyalkyl or carboxyalkyl; R3, R4, R5 and R6 are independently hydrogen, alkyl, cycloalkyl, alkenyl, alkynyl, haloalkyl, aryl, aminoalkyl, hydroxyalkyl, alkoxyalkyl or carboxyalkyl, or R3 and R4 is defined as above, and R5 and R6 together with the nitrogen atom to which they are attached form a heterocycle, including piperidine, piperazine, morpholine; A1 and A2 are independently aryl, heteroaryl, saturated or partially unsaturated carbocycle or saturated or partially unsaturated heterocycle, any of which is optionally substituted; X is one of O, S, NR7, CH2, C(O), NR7C(O), C(O)NR7, SO, SO2 or a covalent bond; where R7 is hydrogen, alkyl, cycloalkyl, alkenyl, alkynyl, haloalkyl, aryl, aminoalkyl, hydroxyalkyl, alkoxyalkyl or carboxyalkyl; n is