A Simple Four‐Step Synthesis of the Potato Alkaloid Demissidine from the Common Sapogenin Tigogenin. Issue 20 (13th March 2023)

• Record Type: Journal Article
• Authors: Baj, Aneta; Kaewnok, Nirawit; Rivas‐Loaiza, Juan A.; Szymańska, Magdalena; Witkowski, Stanisław; Wojtkielewicz, Agnieszka; Morzycki, Jacek W.
• Is Part Of: Chemistry. Volume 29:Issue 20(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-03-13
• Subjects: alkaloids -- demissidine -- natural products chemistry -- solanidanes -- umpolung; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.202203314
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: A simple synthesis method of solanidane alkaloids from common steroidal sapogenins was developed. Previously described multi‐step transformations of tigogenin to demissidine (8–12 steps) were shortened to four steps only. The key‐step of the present synthesis was the epimerization at C25 of the lactam intermediate. Different approaches to this reaction, i. e., a classical one via enolate, and a chemoselective umpolung transformation, were thoroughly investigated. The epimerization step is unnecessary if the starting sapogenin has the same configuration at C25 as the target alkaloid because the configuration at C25 (either R or S ) remains intact throughout the synthesis. Thus, the related solanidane alkaloids, 12β‐hydroxy‐25‐ epi ‐demissidine and 5‐ epi ‐demissidine, were synthesized in the three‐step procedure with retention of configuration at this stereogenic center from rockogenin (25 R ‐5α‐sapogenin) or sarsasapogenin (25 S ‐5β‐sapogenin), respectively. Abstract : A four‐step synthesis of demissidine from tigogenin acetate was developed. The key‐step of the synthesis was the epimerization at C25 of the lactam intermediate.