Seminaphthofluorophore-selenium probes for thioredoxin reductase

A compound according to Formula I, or an ionized form or salt thereof:

• where each bond depicted as “” is a single or double bond as needed to satisfy valence requirements;
• Z1 and Z2 independently are hydrogen, hydroxyl, or thiol, or Z1 and Z2 together with the atoms to which they are attached form a substituted or unsubstituted 6-membered ring;
• X1 is O, S, Se, Si(Ra)(Rb), Ge(Ra)(Rb), Sn(Ra)(Rb)2, C(Ra)(Rb)2, or NRb where Ra is H or C1-C10 alkyl and Rb is H, C1-C10 alkyl, —COOH, or —COORc where Rc is C1-C10 alkyl or a conjugatable moiety;
• R1 is hydrogen, hydroxyl, halogen, thiol, amino, alkyl amino, oxygen, sulfur, imino, iminium, alkyl imino, alkyl iminium, cycloalkyl imino, or a diselenide moiety, and R2 and R3 independently are hydrogen, hydroxy, thiol, C1-C10 alkyl, carboxyalkyl, amino, alkoxy, or halogen, or R1-R3 together with Ring A form a tricyclic ring system with a nitrogen at R1 and a single bond between R1 and ring A;
• R4-R6 independently are hydrogen, hydroxy, thiol, C1-C10 alkyl, carboxyalkyl, amino, alkoxy, or halogen;
• R7, R8, and R10 independently are hydrogen, alkyl, acyl, carboxyl, nitro, amino, alkyl amino, —SO3H, —COOH, or —COORd where Rd is C1-C10 alkyl or a conjugatable moiety;
• R9 is hydrogen, alkyl, acyl, carboxyl, nitro, amino, alkyl amino, —SO3H, a diselenide moiety, —COOH, or —COORd where Rd is C1-C10 alkyl or a conjugatable moiety;
• and
• R11 is one or more atoms forming a ring system with rings C and B and the bond depicted as “” in ring C is a single bond, or R11 is —COOH, —COO− or —COORe where Re is C1-C10 alkyl or a counter ion with a net single positive charge and the bond depicted as “” in ring C is a double bond,
• wherein the compound comprises at least one diselenide moiety, and each diselenide moiety independently has a formula —Y—C(Q)O—(CH2)m—Se—Se—(CH2)n—ORf, where Rf is hydrogen or C1-C3alkyl, Q is O or S, Y is O or N(Rg) where Rg is H or alkyl, and m and n independently are integers from 1-5.