Nucleotide probes

A compound having the following structure (I):

• or a stereoisomer, salt or tautomer thereof, wherein:
• M is, at each occurrence, independently either:
• a) the same or different fluorophore;
• or b) the same or different fluorophore quencher;
• L1a is, at each occurrence, independently a heteroarylene linker;
• L2 and L8 are independently linkers or absent;
• L1b, L3, L5, L6 and L7 are, at each occurrence, independently absent, or alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene or heteroalkynylene linkers;
• L4 is, at each occurrence, independently an alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene or heteroalkynylene linker;
• R1 and R2 each comprise a polynucleotide or —OP(═Ra)(Rb)Rc, provided that at least one of R1 and R2 comprises a polynucleotide;
• R3 is, at each occurrence, independently H, alkyl or alkoxy;
• 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;
• L′ is, at each occurrence, independently a linker comprising a covalent bond to a solid support, a linker comprising a covalent bond to a solid support residue or a linker comprising a covalent bond to a nucleoside;
• m is, at each occurrence, independently an integer of zero or greater;
• n is an integer from 2 to 10;
• and
• q and w are, at each occurrence, independently 0 or 1, provided that at least one occurrence of either q or w is 1.