Extending Cross Metathesis To Identify Selective HDAC Inhibitors: Synthesis, Biological Activities, and Modeling.

Dissymmetric cross metathesis of alkenes as a convergent and general synthetic strategy allowed for the preparation of a new small series of human histone deacetylases (HDAC) inhibitors. Alkenes bearing Boc-protected hydroxamic acid and benzamide and trityl-protected thiols were used to provide the zinc binding groups and were reacted with alkenes bearing aromatic cap groups. One compound was identified as a selective HDAC6 inhibitor lead. Additional biological evaluation in cancer cell lines demonstrated its ability to stimulate the expression of the epithelial marker E-cadherin and tumor suppressor genes like SEMA3F and p21, suggesting a potential use of this compound for lung cancer treatment. Molecular docking on all 11 HDAC isoforms was used to rationalize the observed biological results.

Cross metathesis with hydroxamate and benzamide BOC-protected alkenes to access HDAC inhibitors and their biological evaluation highlighted intrinsic activity of BOC-protected dihydroxamates.

Conditions for the metathesis of alkenes in the convergent synthesis of HDAC inhibitors have been improved by continuous catalyst flow injection in the reaction media. Intermediate and target compounds obtained were tested for their ability to induce HDAC inhibition and tubulin acetylation, revealing the key role of the tert-butyloxycarbonyl (BOC) group for more HDAC6 selectivity. Molecular modelling added rationale for this BOC effect.