Carbopyronone compounds useful as diagnostic adjuvants

A method for tracking cell proliferation and differentiation, the method comprising the steps of:

• a) incubating a mixture of cells and a compound of structural formula (II):
• or a pharmaceutically acceptable salt thereof,
• wherein
• R12 and R13 are each independently H, C1-C6 substituted alkyl, -L-Rx, or -L-Sc;
• R2 is carboxyl, -L-Rx, or -L-Sc;
• R3, R4, R5and R6 are each independently H or halogen;
• R7 and R9 are each C1-C6 alkyl, C1-C6 substituted alkyl, sulfoalky, -L-Rx, or -L-Sc;
• R11, R14, R17, R18, R19, R20, R21 and R22 are each H;
• L is a linker;
• Rx is an acrylamide, a carboxylic acid, an activated ester of a carboxylic acid, an acyl azide, an acyl halide, hydroxy, an aldehyde, an alkyl halide, a sulfonate, an amine, an anhydride, an aniline, an aryl halide, an azide, an aziridine, a boronate, a carbodiimide, a diazoalkane, an epoxide, a glycol, a haloacetamide, a halotriazine, a hydrazine, a hydroxylamine, an imido ester, an isothiocyanate, a ketone, a maleimide, a sulfonyl halide, a thiol group, a succinimidyl ester (SE), a sulfodichlorophenyl (SDP) ester, a sulfotetrafluorophenyl (STP) ester, a tetrafluorophenyl (TFP) ester, a pentafluorophenyl (PFP) ester, a nitrilotriacetic acid (NTA), an aminodextran, and a cyclooctyne-amine;
• and
• Sc is a solid support, a tyramide, an amino acid, a peptide, a protein, a monosaccharide, a polysaccharide, an ion-complexing moiety, a nucleotide, an oligonucleotide, a nucleic acid, a hapten, a drug, a toxin, a lipid, a phospholipid, a lipoprotein, a lipopolysaccharide, a liposome, a lipophilic polymer, a PEG group, a non-biological organic polymer, a polymeric microparticle, an animal cell, a plant cell, a bacterium, a yeast, or a virus;
• b) providing a stimulus to the mixture to elicit a fluorescent signal;
• and
• c) analyzing the stimulated mixture.