Patent ID: 8426462

Claim:
A compound of the following formula (I): or a pharmaceutically acceptable salt thereof, wherein: A1 and A2, independently from each other, are either a bond between the cyclopentadienyl and the carbon of the double bond, or a linear alkyl chain comprising n1 and n2 carbon atoms, respectively, optionally substituted with one or more group(s) selected from halogen; phenyl optionally substituted with OH; (C 1 -C 6 )alkyl optionally substituted with one or more halogen(s); and (C 3 -C 6 )cycloalkyl optionally substituted with one or more halogen(s), wherein n1 and n2 are, independently from each other, an integer comprised between 1 and 4, with the proviso that A1 and A2 are not simultaneously a bond and that the A1-C-A2 chain contains at least 3 carbon atoms, R1 and R2 each represent hydrogen or together form a linear alkyl chain connecting the two cyclopentadienyl groups and having 3 to 5 carbon atoms, wherein said chain is optionally substituted with one or more group(s) selected from halogen; phenyl optionally substituted with OH; (C 1 -C 6 )alkyl optionally substituted with one or more halogen(s); and (C 3 -C 6 )cycloalkyl optionally substituted with one or more halogen(s), and R3 and R4, independently from each other, are hydrogen or a CF 3 , CN, OR 5 or NR 6 R 7 group, wherein: R 5 is hydrogen or a —CO—(C 1 -C 20 )alkyl or —(CH 2 ) m NR 8 R 9 group, R 6 , R 7 , R 8 and R 9 are, independently from one another, hydrogen or a (C 1 -C 6 )alkyl or acyl group, and m is an integer comprised between 2 and 8.