Patent ID: 7504495

Claim:
A quencher composition of the formula (III): wherein L 1 and L 2 are each, independently a bond or a linker; X is a polynucleotide comprising a fluorescent dye; Z is a nucleotide or a polynucleotide both of which are optionally substituted with a label or a solid support; Q is a compound of the formula (I) wherein at least one, two, three or four of R 1 , R 4 , R 5 or R 8 are each, independently selected from substituted or non-substituted amino-alkyl, amino-aryl and amino-alkylaryl, and the remaining R 1 to R 8 groups are each, independently hydrogen or substituted or non-substituted hydroxy, amino, alkyl, aryl, arylalkyl or alkoxy; and wherein Q is attached to the linkers L 1 and L 2 at two different positions, either through one of the α-aminogroups or through the aryl carbons of the quencher moiety.