Hdac inhibiting derivatives of camptothecin

A compound of Formula I, or a pharmaceutically acceptable salt thereof:

• wherein
• Z is deleted, C(RaRb), (CH2)p, (CH2)pNH(CH2)q, CH═N, O, S, C(O), N(Ra), SO2, OC(O), C(O)O, OSO2, S(O2)O, C(O)S, SC(O), C(O)C(O), C(O)N(Ra), N(Ra)C(O), S(O2)N(Ra), N(Ra)S(O2), OC(O)O, OC(O)S, OC(O)N(Ra), OC(O)NH(CH2)p+1NH(CH2)q, N(Ra)C(O)O, N(Ra)C(O)S, or N(Ra)C(O)N(Rb), in which each of Ra and Rb, independently, is H, alkyl, alkenyl, or alkynyl;
• each of p and q, independently, is 0, 1, 2, 3, or 4;
• each R1, R2, and R3, independently, is H, alkyl, alkenyl, alkynyl, cycloalkyl, heterocycloalkyl, cycloalkenyl, heterocycloalkenyl, aryl, heteroaryl, halo, nitro, —CH═NH, oxo, cyano, Si(RcRcRc), alkyl-Si(RcRcRc), alkyl-Rc, alkyl-NRcRc, —CH═NORc, ORc, OC(O)Rc, OC(O)ORc, OC(O)SRc, SRc, C(O)Rc, C(O)ORc, C(O)SRc, C(O)NRcRc, SORc, SO2Rc, NRcRc, N(Rc)C(O)Rc, in which each of Rc independently, is H, alkyl, alkenyl, alkynyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, halo, cyano, nitro, amino, hydroxyl, alkylamino, haloalkyl, or alkoxy, or R1, R2, and the atoms to which they are attached are taken together form a ring, which is optionally substituted with Rc;
• L is —(CH2)m—,
• in which m is 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16;
• each of n and o, independently, is 1, 2, 3, or 4;
• and each W1 and W2, independently, is CH or N.