Preparation and uses of reactive oxygen species scavenger derivatives

A compound of Formula (I)a or Formula (I)b, a pharmaceutically acceptable salts thereof, and individual enantiomers or diastereomers thereof:

• wherein,
• z is 0 or 1;
• L is absent;
• or L is selected from C1-C10 alkyl, C1-C10 alkoxyl, C3-7 cycloalkyl, C1-C10 alkylcycloalkyl, heterocycloalkyl, C1-C10 alkylheterocycloalkyl, C5-10 aryl, C1-C10 alkylaryl, C5-10 heteroaryl, and C1-C10 alkylheteroaryl;
• Q is selected from:
• wherein,
• n is an integer selected from 0 to 10;
• each of R1 and R2 is independently selected from hydrogen and CH3;
• each of R3 and R4 is independently selected from hydrogen and C1-C5 alkyl;
• each W is independently absent or is selected from O and S;
• and
• i) when W is absent, then R3 and R4, optionally, together form the following structure:
• ii) when W is O, then OR3 and OR4 optionally, together form the following structure:
• PEP is a peptidyl moiety having the following structure:
• wherein,
• each asterisk (*) independently denotes a chiral center in either an (S) or (R) configuration;
• m is an integer selected from 0 to 10;
• X1 is selected from hydrogen, —C(═O)—ORm, —S(O)—O—Rm, —S(O2)—O—Rm, —S(O2)—N—(Rm)2 and —C(═O)—N—(Rm)2, where Rm is C1-C6 alkyl, C1-C6 alkoxyl, C1-C6 alkenyl, C1-C6 haloalkyl, C3-C7 cycloalkyl, C1-C6 alkylcycloalkyl, C3-C7 heterocycloalkyl, C1-C6 alkylheterocycloalkyl, C5-C10 aryl, C1-C6 alkylaryl, C5-C10 heteroaryl, and C1-C6 alkylheteroaryl;
• each of X2, X3 and X4 is independently selected from C1-C10 alkyl, C1-C10 alkenyl, C5-C6 aryl, C1-C6 alkylaryl, heteroaryl, and C1-C6 alkylheteroaryl;
• A is absent, or A is selected from Ala, Leu, Ile, Phe, Met, Pro, Gly, Ser, Thr, Cys, Tyr, Asn, Gln, His, Lys, Arg, Asp, Glu, and Val, each of which can be in either a D or L configuration;
• wherein the amino residue is either unprotected, or protected by a protecting group selected from Cbz and Fmoc;
• and
• G is absent, or G is selected from —O—, —S—, —NH—, —NH—C(═O)—O—, —O—C(═O)—NH—, —NH—C(═O)—NH—, —NHSO2—, —SO—, —SO2—, and —NHC(═O)—.