Asymmetric Synthesis of Heterocyclic Analogues of a CGRP Receptor Antagonist for Treating Migraine
摘要:
An asymmetric synthesis of novel heterocyclic analogue of the CGRP receptor antagonist rimegepant (BMS-927711, 3) is reported. The cycloheptane ring was constructed by an intramolecular Heck reaction. The application of Hayashi-Miyaura and Ellman reactions furnished the aryl and the amine chiral centers, while the separable diastereomeric third chiral center alcohols led to both carbamate and urea analogues. This synthetic approach was applicable to both 6- and 5-membered heterocycles as exemplified by pyrazine and thiazole derivatives.
Asymmetric N-Heterocyclic Carbene Catalyzed Addition of Enals to Nitroalkenes: Controlling Stereochemistry via the Homoenolate Reactivity Pathway To Access δ-Lactams
作者:Nicholas A. White、Daniel A. DiRocco、Tomislav Rovis
DOI:10.1021/ja403847e
日期:2013.6.12
An asymmetric intermolecular reaction between enals and nitroalkenes to yield δ-nitroesters has been developed, catalyzed by a novel chiral N-heterocycliccarbene. Key to this work was the development of a catalyst that favors the δ-nitroester pathway over the established Stetter pathway. The reaction proceeds in high stereoselectivity and affords the previously unreported syn diastereomer. We also
The intramolecular dipolar [3+2]-cycloaddition of acyclic δ,ɛ- and ɛ, ζ-unsaturated silyl nitronates was used in the stereoselective synthesis of functionalized cyclopentanone and cyclohexanone, respectively. The reaction with the γ,δ-unsaturated analog did not afford the corresponding cyclobutanone.
Dehydration of β-nitro alcohols catalyzed by Bu2SnO
作者:V. V. Veselovsky、A. V. Lozanova
DOI:10.1007/s11172-011-0263-z
日期:2011.8
β-Nitro alcohols (nitro aldols) in boiling benzene in the presence of Bu2SnO (20–30 mol.%) under neutral conditions undergo dehydration leading to nitroalkenes.
Synthesis of substituted cyclopentanes based on intramolecular [3+2] cycloaddition of trimethylsilyl nitronates generated from 6-nitrohex-1-ene derivatives
作者:A. V. Lozanova、A. V. Stepanov、O. D. Osipova、A. N. Vinnikova、V. V. Veselovsky
DOI:10.1007/s11172-011-0052-8
日期:2011.2
A method for the stereoselective synthesis of substituted 4aS*,7aS*-hexahydrocyclopenta[c]pyran-3(1H)-one, promising synthon of isoprostanes, has been developed based on the intramolecular dipolar [3+2] cycloaddition of silyl nitronates generated from 6-nitrohex-1-ene derivative.