Patent ID: 7799524

Claim:
A compound of formula 1 wherein R 1 -R 2 is a radical of formula 2 wherein R 2 is hydrogen, alkyl of 1 to 10 carbon atoms, or a saccharide moiety; R 5 is hydrogen, halogen, trifluoromethyl, or hydroxy; and R 6 is hydrogen, hydroxy or unsubstituted or substituted amino; and tautomeric forms thereof; X is oxygen or sulfur; R 3 is triazolylene, tetrazolylene, isoxazolylene, thienylene, isoxazolidinylene, or alkynylene, wherein a double bond or the triple bond, respectively, is connected to CH 2 of formula 1; R 4 is an optionally substituted straight or branched chain alkylene group or polyvalent branched chain alkyl group with 1 to 300 carbon atoms, wherein optionally (a) one or more carbon atoms are replaced by oxygen (b) one or more carbon atoms are replaced by nitrogen carrying a hydrogen atom, and a carbon atom adjacent to nitrogen is substituted by oxo; (c) one or more carbon atoms are replaced by oxygen, and a carbon atom adjacent to oxygen is substituted by oxo; (d) the bond between two adjacent carbon atoms is a double or a triple bond; (e) one or more carbon atoms are replaced by a phenylene, a saturated or unsaturated cycloalkylene, a saturated or unsaturated bicycloalkylene, a bridging heteroaromatic or a bridging saturated or unsaturated heterocyclyl group; and/or (f) two adjacent carbon atoms are replaced by a disulfide linkage; and L is one or a plurality of same or different labels connected to R 4 , selected from a spectroscopic probe selected from a fluorophore and a chromophore, a moiety selected from biotin, avidin and streptavidin, a moiety which is capable of generating hydroxyl radicals upon exposure to H 2 O 2 and ascorbate, a moiety which is capable of generating reactive radicals upon irradiation with light, a moiety covalently attached to a solid support, a nucleic acid moiety or a derivative thereof capable of undergoing base-pairing with its complementary strand, a lipid moiety, and a methotrexate moiety attached via a primary carboxy group; or L is a bond connecting R 4 to R 1 forming a cyclic substrate; and or L is a further group —R 3 —CH 2 —X—R 1 -R 2 .