title: Tetracyclic triterpenes. Part VI [1]. The synthesis of 4,4,14 alpha-trimethyl-19 (10 leads to 9 beta) abeo-steroids. Synthons for the preparation of cucurbitacins.
abstract: The effective synthesis of 4,4,14 alpha-trimethyl-19 (10 leads to 9 beta) abeo-steroids (IV), (V), and (VI) with two- and five-carbon side chains from lanosterol is described. Their structures were proved on the basis of spectral data. The title compounds are the first synthetic synthons for the preparation of 4,4,14 alpha-trimethyl-steroids with an unnatural configuration.
mesh_terms: D054728:Cucurbitacins; D014315:Triterpenes / Q000138:chemical synthesis*
chemical_list: D014315:Triterpenes; D054728:Cucurbitacins