Patent ID: 8158782

Claim:
A labeling reactant of formula (I) wherein Ar is selected from the group consisting of phenyl, pyrenyl, antracenyl and naphtyl; A is a linker, formed from one to ten moieties, each moiety being selected from the group consisting of phenylene, alkyl containing 1-12 carbon atoms, ethynediyl (—C═C—), ethylenediyl (—C═C—); ether (—O—), thioether (—S—), amide (—CO—NH— and —NH—CO— and —CO—NR 4 and —NR 4 —CO—), carbonyl (—CO—), ester (—COO— and —OOC—), disulfide (—SS—), diaza (—N═N—) or a tertiary amine (—NR 4 —), where R 4 represents an alkyl containing less than 5 carbon atoms; R 1 and R 2 , same or different, are either protecting groups selected from among trifluoroacetyl, nitrobenzenesulfonyl, t-butoxycarbonyl and fluorenylmethoxycarbonyl, or R 1 and R 2 , same or different, are an acetic acid ester or a radical of wherein R 3 is carboxylic acid, carboxylate ion, or an ester and X 2 is selected from the group consisting of furyl, trismethoxyphenyl and phenylethynyl, where the phenyl is substituted or unsubstituted or X 2 is not present; X is a group for conjugation of the said labeling reactant to a biospecific binding reactant; wherein the reactive group X is selected from amino, aminooxy, haloacetamido, isothiocyanato, 3,5-dichloro-2,4,6-triazinylamino, maleimido, a thioester or an active ester of a carboxylic acid, or the reactive group X is formed from Z-E, where Z is absent or is a radical of a purine base or a pyrimidine base or a 7-deazapurine base, said bases being connected to E via either i) a hydrocarbon chain, which is substituted with a protected hydroxyethyl or hydroxymethyl group, or via ii) a furan ring or pyrane ring; and E is either a phosphorylating moiety where L is absent or is O or S; L″ is H, L′″CH 2 CH 2 CN or L′″Ar′, where Ar′ is phenyl or its substituted derivative, where the substituent is nitro or chlorine, and L′″ is O or S; L″ is O − , S − , Cl, N(i-Pr) 2 ; or E is a solid support tethered to Z via a linker arm, which is the same as or different from the linker -A- as defined above; or the reactive group X is formed from X 3 (NHZ 2 )—, where Z 2 is a transient protecting group and X 3 is a carboxylic acid or its salt, acid halide or active ester; M is a metal or is not present; the indexes n, which are same or different, are 1 or 2; m is 1 or 2; z is 2 or 3.