A compound according to Formula I, wherein R b and R c independently represent a hydrogen atom or an optionally substituted alkyl group or represent the necessary atoms to form an optionally substituted ring structure; LG represents a leaving group precursor selected from the list consisting of: LG' represents a leaving group precursor selected from the list consisting of: wherein R 12, R 13, R 14, R, R and R independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted (hetero)aryl group or wherein R 12 and R 13 or R 14 and R 15 represent the necessary atoms to form a cyclic structure, * represents the linking position of LG and LG' in Formula I; A is selected from the list consisting of: - NR 1 -CO-R 2 - NR 1 -SO 2 -R 3 - NR 4 -SO-R 5 - NR 1 -PO-R 6 R 7 wherein R 1 represents a hydrogen atom, an optionally substituted alkyl group, a -SO 3 group, a -COOR 8 group or an optionally substituted (hetero)aryl group, or R 1 together with at least one of R 9, R 10 and R 11 comprise the necessary atoms to form a ring structure; R 2 represents an optionally substituted alkyl or (hetero)aryl group, -OR 9, -NR 10 R 11 or CF 3; R 3 represents an optionally substituted alkyl group, an optionally substituted (hetero)aryl group, -OR 9, -NR 10 R 11 or -CF 3; R 4 represents a hydrogen atom, an optionally substituted alkyl group or an optionally substituted (hetero)aryl group; R 5 represents an optionally substituted alkyl group or an optionally substituted (hetero)aryl group; R 6 and R 7 independently represent an optionally substituted alkyl group, an optionally substituted aryl group or -OR 9; R 8 represents an optionally substituted aryl group or an optionally alkyl group; R 9 represents is an optionally substituted (hetero)aryl group or an optionally alkyl group; R 10 and R 11 independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted (hetero)aryl group or represent the necessary atoms to form a cyclic structure. R b and R c independently represent a hydrogen atom or an optionally substituted alkyl group or represent the necessary atoms to form an optionally substituted ring structure; LG represents a leaving group precursor selected from the list consisting of: LG' represents a leaving group precursor selected from the list consisting of: wherein R 12, R 13, R 14, R, R and R independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted (hetero)aryl group or wherein R 12 and R 13 or R 14 and R 15 represent the necessary atoms to form a cyclic structure, * represents the linking position of LG and LG' in Formula I; R 12, R 13, R 14, R, R and R independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted (hetero)aryl group or wherein R 12 and R 13 or R 14 and R 15 represent the necessary atoms to form a cyclic structure, * represents the linking position of LG and LG' in Formula I; A is selected from the list consisting of: - NR 1 -CO-R 2 - NR 1 -SO 2 -R 3 - NR 4 -SO-R 5 - NR 1 -PO-R 6 R 7 wherein R 1 represents a hydrogen atom, an optionally substituted alkyl group, a -SO 3 group, a -COOR 8 group or an optionally substituted (hetero)aryl group, or R 1 together with at least one of R 9, R 10 and R 11 comprise the necessary atoms to form a ring structure; R 2 represents an optionally substituted alkyl or (hetero)aryl group, -OR 9, -NR 10 R 11 or CF 3; R 3 represents an optionally substituted alkyl group, an optionally substituted (hetero)aryl group, -OR 9, -NR 10 R 11 or -CF 3; R 4 represents a hydrogen atom, an optionally substituted alkyl group or an optionally substituted (hetero)aryl group; R 5 represents an optionally substituted alkyl group or an optionally substituted (hetero)aryl group; R 6 and R 7 independently represent an optionally substituted alkyl group, an optionally substituted aryl group or -OR 9; R 8 represents an optionally substituted aryl group or an optionally alkyl group; R 9 represents is an optionally substituted (hetero)aryl group or an optionally alkyl group; R 10 and R 11 independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted (hetero)aryl group or represent the necessary atoms to form a cyclic structure. - NR 1 -CO-R 2 - NR 1 -SO 2 -R 3 - NR 4 -SO-R 5 - NR 1 -PO-R 6 R 7 R 1 represents a hydrogen atom, an optionally substituted alkyl group, a -SO 3 group, a -COOR 8 group or an optionally substituted (hetero)aryl group, or R 1 together with at least one of R 9, R 10 and R 11 comprise the necessary atoms to form a ring structure; R 2 represents an optionally substituted alkyl or (hetero)aryl group, -OR 9, -NR 10 R 11 or CF 3; R 3 represents an optionally substituted alkyl group, an optionally substituted (hetero)aryl group, -OR 9, -NR 10 R 11 or -CF 3; R 4 represents a hydrogen atom, an optionally substituted alkyl group or an optionally substituted (hetero)aryl group; R 5 represents an optionally substituted alkyl group or an optionally substituted (hetero)aryl group; R 6 and R 7 independently represent an optionally substituted alkyl group, an optionally substituted aryl group or -OR 9; R 8 represents an optionally substituted aryl group or an optionally alkyl group; R 9 represents is an optionally substituted (hetero)aryl group or an optionally alkyl group; R 10 and R 11 independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted (hetero)aryl group or represent the necessary atoms to form a cyclic structure.