MC1742 is an inhibitor of class I histone deacetylases (HDACs; IC50s = 0.1, 0.11, 0.02, and 0.61 μM for HDAC1, -2, -3, and -8, respectively) and class IIb HDACs (IC50s = 7 and 40 nM for HDAC6 and HDAC10, respectively).1 It is selective for class I and class IIb over class IIa HDACs (IC50s = >50 μM for HDAC4, -5, -7, and -9). MC1742 reduces proliferation of HOS, MG-63, RD, A204, SK-ES-1, and A673 sarcoma cancer stem cells (CSCs). It increases levels of acetylated histone H3 and acetylated tubulin and induces apoptosis in MG-63 CSCs when used at a concentration of 2 μM. MC1742 also reactivates HIV-1 in JLAT 10.6 latently infected cells (EC50 = 350 nM).2 |1. Di Pompo, G., Salerno, M., Rotili, D., et al. Novel histone deacetylase inhibitors induce growth arrest, apoptosis, and differentiation in sarcoma cancer stem cells. J. Med. Chem. 58(9), 4073-4079 (2015).|2. Heffern, E.F.W., Ramani, R., Marshall, G., et al. Identification of isoform-selective hydroxamic acid derivatives that potently reactivate HIV from latency. J. Virus Erad. 5(2), 84-91 (2019).