The enantioselective three-component Michael addition-Pictet-Spengler sequence of beta-ketoesters 1, alpha,beta-unsaturated aldehydes 2 and tryptamines 4 represents a facile and rapid one-pot access to highly substituted indoloquinolizidines in moderate to excellent yields and good to excellent enantioselectivities.
Highly Enantioselective Catalytic Synthesis of Neurite Growth-Promoting Secoyohimbanes
作者:Andrey P. Antonchick、Sara López-Tosco、Juan Parga、Sonja Sievers、Markus Schürmann、Hans Preut、Susanne Höing、Hans R. Schöler、Jared Sterneckert、Daniel Rauh、Herbert Waldmann
DOI:10.1016/j.chembiol.2013.03.011
日期:2013.4
rhynchophylline, a highly enantioselective and efficient organocatalyzed synthesis method was developed that gives access to the tetracyclic secoyohimbane scaffold, embodying a quaternary and three tertiarystereogeniccenters in a one-pot multistep reaction sequence. Investigation of a collection of the secoyohimbanes in primary rat hippocampal neurons and embryonal stem cell-derived motor neurons led
Enantioselective Organocatalytic Synthesis of a Secoyohimbane-Inspired Compound Collection with Neuritogenic Activity
作者:Tim Förster、Sara López-Tosco、Slava Ziegler、Andrey P. Antonchick、Herbert Waldmann
DOI:10.1002/cbic.201700015
日期:2017.6.19
the neuroprotective alkaloid rhynchophylline was synthesized employing a highly efficient enantioselective and organocatalyzed cascade process. Evaluation of the developed compound collection showed a family of neurotrophic compounds.
Asymmetric synthesis of α-alkenyl homoallylic primary amines via 1,2-addition of Grignard reagent to α,β-unsaturated phosphonyl imines
作者:Yiwen Xiong、Haibo Mei、Chen Xie、Jianlin Han、Guigen Li、Yi Pan
DOI:10.1039/c3ra42927j
日期:——
A series of chiral N-phosphonyl protected alpha-alkenyl homoallylic primaryamines were synthesized by asymmetric addition of allylmagnesium bromide Grignard reagent towards chiral alpha,beta-unsaturated imines. Only 1,2-adduct was obtained for all the imines with good yields and excellent diastereoselectivities. The chiral auxiliary could be easily removed under simple conditions, giving free multiple
Proline bulky substituents consecutively act as steric hindrances and directing groups in a Michael/Conia-ene cascade reaction under synergistic catalysis
作者:Salil Putatunda、Juan V. Alegre-Requena、Marta Meazza、Michael Franc、Dominika Rohal'ová、Pooja Vemuri、Ivana Císařová、Raquel P. Herrera、Ramon Rios、Jan Veselý
DOI:10.1039/c8sc05258a
日期:——
different catalysts along the reaction, showing a peculiar feature: the –CPh2OSiMe3 group of the proline catalyst switches its role during the reaction. In the initial Michael reaction, this group plays its commonly-assumed role of bulky blocking group, but the same group generates π–Pd interactions and acts as a directing group in the subsequent Pd-catalyzed Conia-ene reaction. This finding might be very