On the structure and spectroscopic properties of two 13-hydroxysparteine epimers
摘要:
The C-13 and H-1 NNIR spectra of 13 alpha-hydroxysparteine and 13 beta-hydroxysparteine in CDCl3 have permitted identification of their conformation with ring C a boat, the same as that of sparteine. Very weak hydrogen bond involving hydroxy group does not shift a possible conformation equilibrium as it occurs in 13 alpha-hydroxy-2-oxosparteine and 13 beta-hydroxy-2-oxosparteine. (c) 2006 Elsevier B.V. All rights reserved.
The C-13 and H-1 NNIR spectra of 13 alpha-hydroxysparteine and 13 beta-hydroxysparteine in CDCl3 have permitted identification of their conformation with ring C a boat, the same as that of sparteine. Very weak hydrogen bond involving hydroxy group does not shift a possible conformation equilibrium as it occurs in 13 alpha-hydroxy-2-oxosparteine and 13 beta-hydroxy-2-oxosparteine. (c) 2006 Elsevier B.V. All rights reserved.
The Hydroxylated, Tetracyclic Bisquinolizidine Alkaloids Baptifoline and Epibaptifoline: Enantioselective Synthesis and Unambiguous Assignment of their Configuration at C-13
作者:Jessica Goller、Christian B. Hübschle、Matthias Breuning
DOI:10.1002/ejoc.201801126
日期:2019.2.7
Baptifoline and epibaptifoline are C‐13 hydroxylated derivatives of the well‐known bisquinolizidine alkaloid anagyrine. We synthesized both epimers from 11‐allylcytisine and unambiguously determined their debated configuration at the C‐13 stereocenter by NMR, chemical transformation and X‐ray crystallography.