Tubacin

Tubacin (tubulin acetylation inducer) is a small molecule that inhibits histone deacetylase 6 (HDAC6) and induces acetylation of α-tubulin. The use of Tubacin in models of disease has helped to validate, in part, HDAC6 as a drug target, but its non-drug-like structure, high lipophilicity conspire to make it more useful as a research tool than a drug. Tubacin was found to potently inhibit HDAC6, with an IC₅₀ value of 4 nM and approximately 350-fold selectivity over HDAC1. Tubacin induced alpha-tubulin hyperacetylation at ~2.5 to 10 μM concentrations.

Even though tubacin was the first HDAC6 inhibitor identified that targets tubulin acetylation 14 years ago, it remains of great interest, particularly as an antitumor and neuroprotective agent. It is a potent, selective HDAC6 inhibitor. Tubacin was found to inhibit the deacetylation of alpha-tubulin in mammalian cells without affecting histone acetylation, gene expression or cell-cycle progression. An interesting feature of tubacin is the lack of toxicity for normal haematological cells. As a result of its non drug-like structure (MW= 721, PSA 139, ClogP 4.85, 4 HBD, rotatable bonds > 10), tubacin is administered intraperitoneally and is more a useful research tool than a drug.