Nir to swir fluorescent compounds for imaging and detection

A compound represented by one of the following structures:

• or a salt thereof, wherein:
• R1 is independently for each occurrence, hydrogen substituted or unsubstituted C1 to C24 alkyl, substituted or unsubstituted alkylaryl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, sulfonate, aryl sulfonate, alkyl sulfonate, taurine, carboxylate, amine, alkylamine, arylamine, alkylammonium, arylammonium, sulfonamide, halogen, hydroxy, amide, nitro, cyano, azide, O-alkyl, S-alkyl, silyl, trialkylsilyl, O-silyl, haloalkyl, alkylsulfhydryl, trifluoromethyl, hydrazide, substituted or unsubstituted aryl, heteroaryl, or heterocyclic (e.g. morpholine) alkynyl, carboxyalkyl, aminoalkyl, haloalkyl, azidoalkyl, amide, amino acid, or peptide, O, S, N, P, Si, C, (C═C), or L;
• L is absent or is a linker moiety, optionally bearing a functional group or reactive group, wherein said functional group or reactive group is a carboxylate, carboxyalkyl, maleimide, succinimidyl ester, carboxamide, propargyl, azidoalkyl, alkyne, isothiocyanate, of —NH2—OH, —SH, —SO3H, carboxyl, —COCl, —CONHNH2, acetoxymethyl esters, substituted and unsubstituted N-hydroxysuccinimidyl esters, substituted and unsubstituted N-hydroxysulfosuccinimido esters, nitro- or fluoro or phenol esters, azide, —COCH2I, phosphoramidite, phthalamido, acyl fluoride, acyl chloride, acyl azide, tyramide, cinnamamide, hydroxycinnamamide, aldehyde, ketone, phosphoramidite, isocyanate, isothiocyanate, sulfonyl chloride, maleimide or biotin;
• R2 is a substituted or unsubstituted C1 to C24 alkyl, substituted or unsubstituted alkylaryl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, aryl sulfonate, C1 to C24 alkyl sulfonate, C1-C24 alkyl carboxylate, aryl carboxylate, C1-C24 alkylamine, arylamine, C1-C24 alkylammonium, arylammonium, or substituted or unsubstituted polyethylene glycol.