New fluorescent dyes, used for covalent fluorescent labeling of biomolecules, e.g. proteins or nucleic acids, or drugs

摘要

Water-soluble squaric or croconic acid derivative fluorescent labeling dyes (I) are new. Fluorescent dyes of formula (I) are new. E = direct bond or -C(=B)-; A, B, D = O, S or N-R; or at least one may be replaced by CRxRy; R = aliphatic or aromatic group, or a reactive derivative such as (CH2)nCOOH or (CH2)nNH2; Rx, Ry = COOH, COCl, CONH2 or CO-NHS; NHS = N-hydroxy-succinimide; X, Y = O, S, Se, NR or C(Me)2; at least one of R1-R10 = reactive group suitable for covalent bonding to a substrate molecule, selected from (i) NCO, NCS, mono- or dichlorotriazine, aziridine, sulfonyl halide, N-hydroxysuccinimide ester, imido ester, glyxoal and CHO for bonding to amino or hydroxy functions or (ii) maleimide or iodoacetamide for bonding to thiol functions; the reactive group optionally being bonded to the chromophore via a spacer of formula (CH2)n; n = 1-18; at least one of R1-R10 = ionizable substituent providing hydrophilicity, such as SO3-, COO- or N(R)3+; R3-R10 may also = groups forming further fused aromatic or heterocyclic rings.