or the pharmaceutically acceptable salts thereof;

wherein each of rings A and B is independently a pyridinyl optionally substituted with one or more substituents selected from the group consisting of alkyl (C_1-10), alkenyl (C_2-10), and alkynyl (C_2-10);

ring C is an unsubstituted piperidine or is piperidine substituted only at position 4 with OH, OMe, CN, OBz, ═NOEt, or ═NOBz;

wherein Y is phenyl, benzimidazole or imidazole; or

is selected from the group consisting of,

—(CH₂)_m NH₂,

—(CH₂)_m NHCH₃,

—(CH₂)_m NH(CH₂)_mNH₂,

—(CH₂)_m NH(CH₂)_mNH(CH₂)mNH₂,

—(CH₂)_m OH,

—(CH₂)_m CO(CH₂)_mOH,

—(CH₂)_m CO(CH₂)_mNH₂,

—(CH₂)_m CO(CH₂)_mNH(CH₂)_mNH₂,

—(CH₂)_m NHCO(CH₂)_mNH₂,

—(CH₂)_m NH (CH₂)_mCO₂H,

—(CH₂)_m NH (CH₂)_mSO₂H,

—(CH₂)_m NHCO(CH₂)_mNH(CH₂)_mNH₂,

—(CH₂)_m NHCO(CH₂)_mNH(CH₂)_mNH(CH₂)_mNH(CH₂)_mNH₂,

—(CH₂)_m NH(CH₂)_mOH,

—(CH₂)_m CH═NOH,

—(CH₂)_m CONH(CH₂)_mOH,

—(CH₂)_m N[(CH₂)_mCO₂H]₂,

—(CH₂)_m NHCOZ and

—(CH₂)_m NH—(CH₂)_mZ,

wherein each m is independently 0-4; and Z is an optionally substituted aromatic or heteroaromatic moiety containing 5-12 ring members;

L is (CR³₂)₁ where each R³ is H or alkyl wherein a single bond in alkyl may be replaced with a double or triple bond and wherein 1 is 1-6.