Fluorescent substrates for monoamine transporters as optical false neurotransmitters

A compound having the following structure:

• wherein
• Y is O, X is O, bond α is absent and bond β is present;
• R3 is —H, —OH, alkyl, alkenyl, alkynyl, or halo,
• R4 is —H, —R11N(R35)2, —N(R35)R17N(R35)2, —R17N(H)R18, —R11NR13R14, —N(R35) alkyl, or a piperazine group,
• wherein R11 is a straight or a branched chain C2-C6 alkylene, C2-C6 alkenylene or C2-C6 alkynylene, and
• wherein the (R35)2 group may be attached to any carbon atom of the R11 group,
• wherein R13 or R14 or both are, independently, methyl or ethyl,
• wherein R17 is a straight or a branched chain C2-C6 alkylene, C2-C6 alkenylene or C2-C6 alkynylene,
• wherein R18 is a straight or a branched chain alkyl, alkenyl or alkynyl,
• where each occurrence of R35 is, independently, —H, —CH3 or —C2H5;
• R5 is —H, —R12N(R36)2, R11NR15R16, —N(R36) alkyl, —N(R36)2, a piperazine group, a mono-substituted heterocyclyl or —R19W,
• wherein R12 is a straight or a branched chain C1-C6 alkylene, C1-C6 alkenylene or C1-C6 alkynylene, and
• wherein the NH2 group may be attached to any carbon atom of the R12 group,
• wherein R15 or R16 or both are, independently, methyl or ethyl,
• wherein R19 is a straight or a branched chain C1-C6 alkylene, C1-C6 alkenylene or C1-C6 alkynylene,
• wherein W is a mono- or di-substituted heterocyclyl group or a mono-substituted heterocyclyl cation,
• where each occurrence of R36 is, independently, —H, —CH3 or —C2H5;
• when one of R4 or R5 is —H, then the other of R4 or R5 is other than —H;
• and
• wherein the compound contains an N(Rx) or N(Rx)2 group wherein each occurrence of Rx is, independently, —H, —CH3 or —C2H5
• or a salt of the compound.