Light-emitting biomarker

A compound of general formula (I):

• S—B-A
• in which:
• S represents a labile structure that can be activated by a biological entity, and S having the general formula (VI):
• P-L-□
• in which:
• □ symbolizes a covalent bond with B;
• P represents a substrate that can be recognized by the biological entity;
• and
• L represents an oxygen, sulfur, nitrogen, carbonyl or a —CO-Q- functional group, with Q being O, S or NH;
• B is a reactive branch, of which the chemical structure is such that the activation of the labile structure S induces intramolecular rearrangement in a suitable form for releasing a molecule A−;
• and B having the general formula (III):
• in which:
• □ and ⋄ symbolize, respectively, a covalent bond with the labile structure S and a chromophore A;
• j is an integer ranging from 0 to 2;
• R4 is a C1-C20 hydrocarbon-based chain, where appropriate interrupted by one or more heteroatoms and/or space —CO and/or —N(alkyl)-unit(s), located ortho, meta or para to the □-(CH2)j-radical, and chosen from —(CH2)k-⋄, —(CH2)k—C(O)-⋄, and —CH2—O—C(O)—N(CH3)—(CH2)2—N(CH3)—C(O)-⋄ radicals, with k being equal to 1 or 2;
• R5 and R6 are, independently of one another, a hydrogen atom or a saturated or unsaturated, linear, branched or cyclic, C1-C20 hydrocarbon-based chain chosen from an alkyl radical, an alkoxy radical, an alkylamino or dialkylamino radical, an alkylthio and a C6-C30 aromatic ring chosen from an aryl radical, an aryloxy radical, an arylamino radical and an arylthio radical
• A is a chromophore of formula (IIa):
• in which:
• ⋄ symbolizes the covalent bond with B;
• R1 is a saturated or unsaturated, linear, branched or cyclic, C1-C6 alkyl or C1-C6 alkoxy radical, optionally comprising one or more atoms chosen from O, N and S, and is optionally substituted;
• R2 and R3 are linked to form a spiro adamantyl radical with the carbon of the dioxetane ring which bears R2 and R3 substituted where appropriate;
• Ar represents a C6-C30 arylene radical of general formula (IVa):
• in which:
• Δ symbolizes a covalent bond with X and * symbolizes a covalent bond with the dioxetane ring;
• R10 represents a hydrogen atom, an electroactive radical or a fluorescent radical;
• and
• R11 is chosen from a hydrogen atom and a C6-C10 aryl radical fused with the phenylene radical, and
• X represents O, NH or S;
• and derivatives thereof.