Cyclized fluorescent nucleic acid intercalating cyanine dyes and nucleic acid detection methods

摘要

New intercalating cyanine dyes are provided in which the benzothiazole portion of the cyanine dye has been modified to produce dyes with improved properties for labelling nucleic acids. These new intercalating cyanine dyes are cyclized fluorescent cyanine dyes represented by General Formula I ##STR1## where: n is 0, 1 or 2;P PY may be either S or O;PPR.sub.3 and R.sub.4 may each independently be either hydrogen, C.sub.1 -C.sub.10 alkyl, C.sub.1 - C.sub. 10 alkoxy or C.sub.1 -C.sub.10 alkylthio;PPR.sub.5 may be C.sub.1 -C.sub.50 alkyl, preferably substituted with one or more polar substituents which preferably includes one or more positively charged atoms, or a cyclized fluorescent cyanine dye of the present invention, i. e., where R.sub.5 is a linker between two cyclized fluorescent cyanine dyes;PPR.sub.6 and R.sub.7 may each independently be either H and C.sub.1-10 alkyl, or may be taken together to form a 5 or 6 membered ring, most preferably a 6 membered aromatic ring, optionally substituted with C.sub.1-6 alkyl or C.sub.1 -C.sub.10 alkoxy groups; PPR.sub.8 and R.sub.9 may each independently be either H and C.sub.1-10 alkyl, or may be taken together to form a 5 or 6 membered ring, most preferably a 6 membered aromatic ring, optionally substituted with C.sub.1-6 alkyl or C.sub.1 -C.sub.10 alkoxy groups; andPP R.sub.10 may be either H, C.sub.1-6 alkyl, C.sub.1 -C.sub.10 alkoxy or a fused benzene.PPAs used above, alkyl and alkoxy refer to any substituent having a carbon backbone having the specified range of carbon atoms. The carbon backbone may form a straight chain, may be branched or may be cyclic. The alkyl and alkoxy groups may be optionally substituted by a wide variety of substituents including, for example, alcohols, amines, thiols, phosphates, halides, ethers, esters, ketones, aldehydes, carboxylic acids, amides, cycloalkyls, and aromatic rings.