Cyanine dyes and their applications as luminescence quenching compounds

A compound, having Formula I:

• wherein A represents the atoms necessary to form a nitrogen-containing five-membered heterocyclic ring that has zero to three fused aromatic rings having 6 atoms in each ring selected from the group consisting of C, CH, CH2, C(alkyl)2, O, S, NH and N-alkyl provided that said five-membered ring contains ═N(alkyl) coupled to the bridged and conjugated double bonds, wherein aromatic carbon atoms are optionally substituted one or more times by substituents selected from the group consisting of hydrogen, alkyl having from 1-20 carbons, alkoxy having from 1-20 carbons, trifluoromethyl, halogen, methylthio, sulfonyl, carbonyl, hydroxy, amino, thiol, RM and LQM.
• B is selected from a conjugated cyclic moiety that has a condensable carbon atom of 2-alkylindolium, 2-alkylbenzothiazolium, 2-alkylbenzoimidazolium, 2-alkylbenzoxazolium, barbituric acid, thiobarbituric acid, α-cyanocarbonyl compounds and α, β-dicarbonyl (e.g. malonyl compounds), wherein carbon or nitrogen atoms are optionally substituted one or more times by substituents selected from the group consisting of hydrogen, alkyl having from 1-20 carbons, alkoxy having from 1-20 carbons, trifluoromethyl, halogen, methylthio, sulfonyl, carbonyl, hydroxy, amino, thiol, RM and LQM.
• n is 0 to 3.
• R1, R2, and R3 are independently selected from the group consisting of hydrogen, alkyl having 1-6 carbons, cycloalkyl having 3-10 carbons, aryl, heteroaryl, RM and LQM
• RM is a chemically reactive group;
• LMQ is a heterocyclic moiety that quenches luminescence of said chromophore.