Patent ID: 8173809

Claim:
A method of treating schizophrenia in a subject comprising administering to said subject an effective amount of a cysteine prodrug having the structure: wherein: R 1 and R 2 are independently selected from OH, ═O, or a branched or straight chain C 1 to C 5 alkoxy group, with the caveat that when ═O is selected the nitrogen atom adjacent the carbonyl group thusly formed bears a H and a single bond joins the adjacent nitrogen to said carbonyl group; R 3 is H, a branched or straight chain C 1 to C 5 alkyl, a nitrobenzenesulfonyl, a trityl, an aryl thio, an aryl, an alkylthio, an acyl, a benzoyl, a thio acyl, a thio benzoyl, or a benzyl group; and R 4 is selected from the side chain groups of the natural L-amino acids cys, gly, phe, pro, val, ser, arg, asp, asn, glu, gln, ala, his, ile, leu, lys, met, thr, trp, tyr, or D-stereoisomers thereof, wherein when R 4 is the pro side chain group, R 4 consists of —CH 2 CH 2 CH 2 — that bridges the carbon atom to which R 4 is attached to the adjoining nitrogen atom; or, a cystine dimer of said prodrug having the structure: wherein: R 1 , R 2, R 5 and R 6 are independently selected from OH, ═O, or a branched or straight chain C 1 to C 5 alkoxy group, with the caveat that when ═O is selected the nitrogen atom adjacent the carbonyl group thusly formed bears a H and a single bond joins the adjacent nitrogen to said carbonyl group; and R 4 and R 7 are independently selected from the side chain groups of the natural L-amino acids cys, gly, phe, pro, val, ser, arg, asp, asn, glu, gln, ala, his, ile, leu, lys, met, thr, trp, tyr, or D-stereoisomers thereof, wherein when R 4 is the pro side chain group, R 4 consists of —CH 2 CH 2 CH 2 — that bridges the carbon atom to which R 4 is attached to the adjoining nitrogen atom, and when R 7 is the pro side chain group, R 7 consists of —CH 2 CH 2 CH 2 — that bridges the carbon atom to which R 7 is attached to the adjoining nitrogen atom, whereby schizophrenia is treated in said subject.