Ultra bright dimeric or polymeric dyes with spacing linker groups

A method for preparing a conjugate of a compound, comprising:

• admixing a compound or a stereoisomer, salt or tautomer thereof, with an antibody, wherein the compound is conjugated to a sulfur atom of the antibody, and wherein the first compound has the following structure (I):
• wherein:
• M is, at each occurrence, independently a fluorescent dye;
• L′ is at each occurrence, independently either:
• i) an optional alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene, heteroalkynylene or heteroatomic linker;
• or ii) a linker comprising a functional group capable of formation by reaction of two complementary reactive groups;
• 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 a polyethylene oxide linker;
• R1 is, at each occurrence, independently H, alkyl or alkoxy;
• R2 and R3 are each independently H, OH, SH, alkyl, alkoxy, alkylether, heteroalkyl, —OP(═Ra)(Rb)Rc, Q, or a protected form thereof, or L′;
• R4 is, at each occurrence, independently OH, SH, O—, S—, ORd or SRd;
• R5 is, at each occurrence, independently oxo, thioxo or absent;
• Ra is O or S;
• Rb is OH, SH, O, S—, ORd or SRd;
• Rc is OH, SH, O, S—, ORd, OL′, SRd, alkyl, alkoxy, heteroalkyl, heteroalkoxy, alkylether, alkoxyalkylether, phosphate, thiophosphate, phosphoalkyl, thiophosphoalkyl, phosphoalkylether or thiophosphoalkylether;
• Ra is a counter ion;
• Q is, at each occurrence, independently a moiety comprising a reactive group, or protected form thereof, capable of forming a covalent bond with the antibody;
• L′ is, at each occurrence, independently a linker comprising a covalent bond to Q, a linker comprising a covalent bond to the antibody;
• m is, at each occurrence, independently an integer of one or greater, and
• n is an integer of one or greater,
• provided that at least one occurrence of either R2 and R3 is —OP(═Ra)(Rs)Rc, Q, or a protected form thereof, or L′, wherein Rc is OL′.

A method of conjugating a polymeric dye compound to an analyte or targeting moiety, comprising:

• admixing the polymeric dye compound, or a stereoisomer, salt or tautomer thereof, with the analyte or targeting moiety having specificity for the analyte, wherein the dye compound is conjugated to a sulfur atom of the analyte or targeting moiety, and wherein the polymeric dye compound has the following structure of (I):
• wherein:
• M is, at each occurrence, independently a fluorescent dye;
• L′ is at each occurrence, independently either:
• i) an optional alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene, heteroalkynylene or heteroatomic linker;
• or ii) a linker comprising a functional group capable of formation by reaction of two complementary reactive groups;
• 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 a polyethylene oxide linker;
• R1 is, at each occurrence, independently H, alkyl or alkoxy;
• R2 and R3 are each independently H, OH, SH, alkyl, alkoxy, alkylether, heteroalkyl, —OP(═Ra)(Rb)Rc, Q, or a protected form thereof, or L′;
• R4 is, at each occurrence, independently OH, SH, O—, S—, ORd or SRd;
• R5 is, at each occurrence, independently oxo, thioxo or absent;
• Ra is O or S;
• Rb is OH, SH, O—, S—, ORd or SRd;
• Rc is OH, SH, O—, S—, ORd, OL′, SRd, alkyl, alkoxy, heteroalkyl, heteroalkoxy, alkylether, alkoxyalkylether, phosphate, thiophosphate, phosphoalkyl, thiophosphoalkyl, phosphoalkylether or thiophosphoalkylether;
• Rd is a counter ion;
• Q is, at each occurrence, independently a moiety comprising a reactive group, or protected form thereof, capable of forming a covalent bond with the analyte or targeting moiety;
• L′ is, at each occurrence, independently a linker comprising a covalent bond to Q, a linker comprising a covalent bond to the analyte or targeting moiety;
• m is, at each occurrence, independently an integer of one or greater;
• and
• n is an integer of one or greater,
• provided that at least one occurrence of either R2 and R3 is —OP(═Ra)(Rb)Rc, Q, or a protected form thereof, or L′, wherein Rc is OL′.