Aminodiols, aminotetraols and 1,2,3-triazoles based on allo-gibberic acid: stereoselective syntheses and antiproliferative activities†

A new series of aminodiols, aminotetraols and 1,2,3-triazoles based on allo-gibberic acid were synthesized in a stereoselective manner, starting from commercially available gibberellic acid. allo-Gibberic acid, prepared from gibberellic acid according to a literature method, was applied to SeO₂/t-BuOOH-mediated allylic oxidation, yielding the triol, which is a key intermediate. After protecting the 1,4-diol functionality as acetonide, epoxidation was performed using either m-CPBA or t-BuOOH/VO(acac)₂ to produce the epoxy alcohol. Then, the oxirane ring was opened with either primary amines to provide aminodiols or sodium azide to afford azido diols. The latter was subjected to the CuAAC reaction to obtain dihydroxy 1,2,3-triazoles. HCl-mediated acetonide deprotection of the prepared derivatives furnished aminotetraols and tetrahydroxy 1,2,3-triazoles. The antiproliferative effects of the prepared compounds were studied by the in vitro MTT method against a panel of human cancer cell lines (HeLa, SiHa, A2780, MCF-7 and MDA-MB-231) and fibroblasts, and the structure–activity relationships for the prepared compounds were explored.