Chemiluminescent probes for diagnostics and in vivo imaging

A compound of the formula I:

• wherein
• R1 is selected from the group consisting of a linear or branched (C1-C18)alkyl, and (C3-C7)cycloalkyl;
• R2 and R3 each independently is selected from the group consisting of a branched (C3-C18)alkyl and (C3-C7)cycloalkyl, or R2 and R3 together with the carbon atom to which they are attached form a fused, spiro or bridged cyclic or polycyclic ring;
• R5 and R6 each independently is selected from the group consisting of H, (C1-C18)alkyl, (C2-C18)alkenyl, (C2-C18)alkynyl, (C3-C7)cycloalkyl, and aryl, or R5 and R6 together with the oxygen atoms to which they are attached form a heterocyclic ring;
• R7, R8 and R9 each independently is H, or an electron acceptor group selected from the group consisting of halogen, —NO2, —CN, —COOR10, —C(═O)R10 and —SO2R10;
• R10 each independently is H or —(C1-C18)alkyl;
• and
• Q is a protecting group.