Ultra bright dimeric or polymeric dyes

A compound having the following structure (I):

• or a stereoisomer, salt or tautomer thereof, wherein:
• M is, at each occurrence, independently a moiety comprising two or more carbon-carbon double bonds and at least one degree of conjugation, and at least one occurrence of M is a moiety comprising three or more rings selected from aryl and heteroaryl rings;
• L1 is, at each occurrence, independently a linker comprising an alkene, ester, amide, thioester, disulfide, carbocyclic, heterocyclic or heteroaryl group;
• L2 and L3 are, at each occurrence, independently an optional alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene, heteroalkynylene or heteroatomic linker;
• L4 is, at each occurrence, independently an alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene or heteroalkynylene linker;
• R1 is, at each occurrence, independently H, alkyl or alkoxy;
• one of R2 and R3 is OH or —OP(═Ra)(Rb)Rc, and the other one of R2 and R3 is Q, a linker comprising a covalent bond to Q, a linker comprising a covalent bond to an analyte molecule or a linker comprising a covalent bond to a solid support, wherein:
• Ra is O or S;
• Rb is OH, SH, O−, S−, ORd or SRd;
• Rc is OH, SH, O−, S−, ORd, SRd, alkyl, alkoxy, alkylether, alkoxyalkylether, phosphate, thiophosphate, phosphoalkyl, thiophosphoalkyl, phosphoalkylether or thiophosphoalkylether;
• and Rd is a counter ion;
• R4 is, at each occurrence, independently OH, SH, O−, S−, ORd or SRd;
• R5 is, at each occurrence, independently oxo, thioxo or absent;
• Q is, at each occurrence, independently a moiety comprising a sulfhydryl, disulfide, activated ester, isothiocyanate azide, alkyne, alkene, diene, dienophile, acid halide, sulfonyl halide, phosphine, α-haloamide, biotin, amino or maleimide functional group;
• m is, at each occurrence, independently an integer of zero or greater, wherein at least one occurrence of m is an integer of two or greater;
• and
• n is an integer of one or greater.