Benzoic acid esters of oxazolidinones having a hydroxyacetylpiperazine substituent

A compound of formula I:

• or a pharmaceutically acceptable salt thereof wherein:
• A is a structure i, ii, or iii
• W is
• a) NHC(═X)R1,
• b) —O—het, —S—het, or —NH—het;
• provided that when A is a structure iv, W is not the section b);
• X is O, or S;
• R1 is
• (a) H,
• (b) NH2,
• (c) NHC1-4alkyl,
• (d) C1-4alkyl, optionally substituted by one or more F, Cl, or CN,
• (e) C2-4alkenyl,
• (f) OC1-4alkyl,
• (g) SC1-4alkyl, or
• (h) (CH2)nC3-6cycloalkyl;
• R2 and R3 are independently H, F, Cl or C1-2alkyl;
• R4 is positioned at either C-3 or C-4 and is:
• R5 is H, or CH3;
• R6 is H, or C1-4alkyl, optionally substituted by OH, SH, SCH3, NH2 or NHC(═NH)NH2;
• R7 and R8 are independently
• (a) H,
• (b) C1-4alkyl, or
• (c) R7 and R8 together with the nitrogen to which they are attached to form a saturated 5-, 6-, or 7-membered heterocyclic ring which may have additional heteroatoms selected from the group consisting of O, S(O)n, or or N—R5;
• het is a C-linked five- (5) or six- (6) membered saturated or unsaturated heterocyclic ring having 1, 2, or 3 heteroatoms selected from the group consisting of oxygen, sulfur, and nitrogen, which is optionally fused to a benzene ring;
• at each occurrence, wherein het is optionally substituted with one or more halo, OH, CF3, OC1-6alkyl, CN, C1-6 alkyl, S(═O)iR9, C(═X)R10, OC(═O)R10, NHC(═O)R10, or NR10R10, oxo, or oxime;
• wherein R9 is C1-6alkyl, aryl, or NR7R8;
• R10 is H, C1-6alkyl, aryl, or NR7R8;
• n is 0, 1, or 2;
• and with the proviso that when X is O, R4 is not the subsection (a).