2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine analogs and methods for their synthesis and use

A compound or salt thereof, said compound having a general formula selected from (I), (II), (III), (IV), or (V):

• wherein R and R1 are each —CH2—R2, where R2 is a linkage chemistry which provides a terminal functional moiety selected from the group consisting of protected or unprotected sulfhydryl moieties, protected or unprotected amine moieties, primary amine-reactive moieties, sulfhydryl-reactive moieties, photoreactive moieties, carboxyl-reactive moieties, arginine-reactive moieties, and carbonyl-reactive moieties;
• X is H, N, O, C1-6 saturated alkyl straight or branched chain, C1-6 unsaturated alkyl straight or branched chain, C1-6 alkoxy, or haloalkyl;
• Y is H, C1-6 saturated alkyl straight or branched chain, C1-6 unsaturated alkyl straight or branched chain, C1-6 alkoxy, or haloalkyl;
• Z is H, C1-6 saturated alkyl straight or branched chain, C1-6 unsaturated alkyl straight or branched chain, C1-6 alkoxy, or haloalkyl.