856433-01-7Relevant academic research and scientific papers
Complex Polyheterocycles and the Stereochemical Reassignment of Pileamartine A via Aza-Heck Triggered Aryl C-H Functionalization Cascades
Bower, John F.,Caiger, Lewis,García-Cárceles, Javier,Hazelden, Ian R.,Jones, Benjamin T.,Langer, Thomas,Lewis, Richard J.
, p. 15593 - 15598 (2021/10/12)
Structurally complex benzo- and spiro-fused N-polyheterocycles can be accessed via intramolecular Pd(0)-catalyzed alkene 1,2-aminoarylation reactions. The method uses N-(pentafluorobenzoyloxy)carbamates as the initiating motif, and this allows aza-Heck-type alkene amino-palladation in advance of C-H palladation of the aromatic component. The chemistry is showcased in the first total synthesis of the complex alkaloid (+)-pileamartine A, which has resulted in the reassignment of its absolute stereochemistry.
Enantioselective hydroesterificative cyclization of 1,6-enynes to chiral γ-lactams bearing a quaternary carbon stereocenter
Dong, Kaiwu,Li, Huimin,Ren, Xinyi,Shen, Chaoren,Tang, Lin,Wang, Peng
supporting information, p. 3561 - 3566 (2021/05/29)
A palladium-catalyzed asymmetric hydroesterification-cyclization of 1,6-enynes with CO and alcohol was developed to efficiently prepare a variety of enantioenriched γ-lactams bearing a chiral quaternary carbon center and a carboxylic ester group. The approach featured good to high chemo-, region-, and enantioselectivities, high atom economy, and mild reaction conditions as well as broad substrate scope. The correlation between the multiple selectivities of such process and the N-substitutes of the amide linker in the 1,6-enyne substrate has been depicted by the crystallographic evidence and control experiments.
Stereoselective syntheses of 4-hydroxy 4-substituted glutamic acids
Tamura, Osamu,Shiro, Tomoya,Ogasawara, Mizuho,Toyao, Atsushi,Ishibashi, Hiroyuki
, p. 4569 - 4577 (2007/10/03)
The 4-hydroxy 4-substituted glutamic acid moiety is a common substructure of biologically important natural products such as monatin [(2S,4S)-2], lycoperdic acid (3), and dysiherbaine (4). To develop methodology for syntheses of these natural products, cycloadditions of nitrone 5 with 2-substituted 2-propen-1-ols 6 and 2-substituted acrylates 8 were investigated. Reactions of nitrone 5 with alcohols 6 in the presence of MgBr2OEt2 gave cycloadducts 7 in a highly stereoselective manner, whereas noncatalyzed reactions of 5 with acrylates 8 afforded adducts 9. Using the former reaction, syntheses of monatin [(2S,4S)-2], monatin derivative 18, and lycoperdic acid (3) were accomplished. The C4-epimer of monatin [(2S,4R)-2)] was also synthesized by employing the latter cycloaddition.
