Studies towards the synthesis of polyhydroxylated pyrrolidine alkaloids isolated from Broussonetia kazinoki (moraceae). (3rd December 2022)

• Record Type: Journal Article
• Authors: Bouillon, Marc E.; Nash, Robert J.; Pyne, Stephen G.
• Is Part Of: Tetrahedron. Volume 128(2022)
• Publication Date: 2022-12-03
• Subjects: Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tet.2022.133104
• Languages: English
• ISSNs: 0040-4020

Abstract

Abstract: The syntheses of L-AB1, L-DMDP, and the novel compounds, (−)-phenethyl-L-AB1, (−)-10′-deoxobroussonetine C, (−)-10′-deoxobroussonetine E, (−)-1′-epi-10′-deoxobroussonetine E, and (−)-(6S)-12′-hydroxydodecylmoranoline are reported. These syntheses start from d -xylose employing the Petasis borono-Mannich reaction to stereoselectively introduce the amino group, followed by a chemo- and regioselective O-mesylation to deliver the fully functionalized pyrrolidine moiety after intramolecular SN 2-cyclisation. The synthesis of the latter targeted compound involved a ring expansion process of a prolinol moiety to a piperidine derivative under Mitsunobu reaction conditions. An attempted synthesis of desired ent-broussonetine C was unsuccesful due to formation of an unexpected tetrahydrofuran derivative in the final stage of the synthesis. The glycosidase inhibitory activities of four of the new target compounds against a panel of ten glycosidaes is also presented. Graphical abstract: Image 1