A compound of the formula I ** Formula ** in which: R1 is selected from the group consisting of: i) H, ii) -C1-6 alkyl, unsubstituted or substituted 1 to 5 times by substituents individually selected from the group consisting of OH, halogen, cyano and C1-6 alkoxy, iii) -S (O) 2-C1-6 alkyl, whose C1-6 alkyl is unsubstituted or substituted 1 to 5 times by substituents individually selected from the group consisting of OH, halogen, cyano and C1-6 alkoxy, iv) -C (O) -C1-6 alkyl, whose C1-6 alkyl is unsubstituted or substituted 1 to 5 times by substituents chosen individually from the group formed by OH, halogen, cyano and C1-6 alkoxy, v) -C (O) O-C1-6 alkyl, whose C1-6 alkyl is unsubstituted or substituted 1 to 5 times by substituents individually selected from the group formed by OH, halogen, cyano and C1-6 alkoxy； vi) cycloalkyl, unsubstituted or substituted 1 to 5 times by substituents individually selected from the group consisting of OH, halogen, cyano, C1-6 alkyl and C1-6 alkoxy； vii) S (O) 2- (CH2) q-NRiRii, in which q is the number 0 or 1, Ri and Rii independently of each other are chosen from the group consisting of H and C1-6 alkyl, or Ri and Rii together with the nitrogen to which they are attached form a heterocyclyl of 3 to 7 links containing one or two heteroatoms chosen individually from N, O and S, and said heterocyclyl is unsubstituted or substituted 1 to 5 times by substituents chosen individually from the group consisting of oxo, halogen, C1-6 alkyl and C1-6 alkoxy, viii) - (CH2) r-NRiiiRiv, in which r is number 1, 2 or 3, Riii and Riv are independently selected from each other between the group formed by H and C1-6 alkyl, or Riii and Riv together with the nitrogen to which they are attached form a heterocyclyl of 3 to 7 links containing one or two heteroatoms chosen individually between N, O and S, and said heterocyclyl is unsubstituted or substituted 1 to 5 times by substituents chosen individually from the group consisting of oxo, halogen or, C1-6
