{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Nicholson JM"],"funding":["National Institute of General Medical Sciences","NIGMS NIH HHS"],"pagination":["5687-5691"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC10654682"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["25(30)"],"pubmed_abstract":["Asymmetric <i>de novo</i> syntheses of euphol and tirucallol have been accomplished by way of a concise sequence of chemical steps featuring several modern stereoselective transformations. The preparative solution described for these complex problems in natural product synthesis departs significantly from biomimetic polyene cyclization chemistry, which has been leveraged to address related tetracyclic triterpenoid targets. In particular, a diastereoselective Friedel-Crafts-type cyclization was employed to establish a tetracycle bearing a stereodefined quaternary center at C9 (steroid numbering) that provided access to intermediates of relevance for introducing the C10 and C14 quaternary centers by sequential stereospecific 1,2-alkyl shifts (C9 → C10 and C15 → C14). Finally, the stereodefin"],"journal":["Organic letters"],"pubmed_title":["Asymmetric Total Syntheses of Euphol and Tirucallol."],"pmcid":["PMC10654682"],"funding_grant_id":["R35 GM134725"],"pubmed_authors":["Micalizio GC","Nicholson JM"],"additional_accession":[]},"is_claimable":false,"name":"Asymmetric Total Syntheses of Euphol and Tirucallol.","description":"Asymmetric <i>de novo</i> syntheses of euphol and tirucallol have been accomplished by way of a concise sequence of chemical steps featuring several modern stereoselective transformations. The preparative solution described for these complex problems in natural product synthesis departs significantly from biomimetic polyene cyclization chemistry, which has been leveraged to address related tetracyclic triterpenoid targets. In particular, a diastereoselective Friedel-Crafts-type cyclization was employed to establish a tetracycle bearing a stereodefined quaternary center at C9 (steroid numbering) that provided access to intermediates of relevance for introducing the C10 and C14 quaternary centers by sequential stereospecific 1,2-alkyl shifts (C9 → C10 and C15 → C14). Finally, the stereodefin","dates":{"release":"2023-01-01T00:00:00Z","publication":"2023 Aug","modification":"2025-04-19T20:45:26.781Z","creation":"2025-04-19T20:45:26.781Z"},"accession":"S-EPMC10654682","cross_references":{"pubmed":["37477981"],"doi":["10.1021/acs.orglett.3c02187"]}}