https://purehost.bath.ac.uk/ws/files/455786/Lewis_Tetrahedron_2006_62_37_8655.pdf

Recent advances in the chemistry of macroline, sarpagine and ajmaline-related indole alkaloids

Ag-Catalyzed Diastereo- and Enantioselective Synthesis of β-Substituted Tryptophans from Sulfonylindoles

Non-phenolic oxidative coupling: The first total synthesis of the C-2 symmetric indole alkaloid P-(+)-dispegatrine (1) is reported. A late-stage thallium(III)acetate mediated intermolecular oxidative coupling was employed to construct the C(9)-C(9′) bond with complete regio- and stereocontrol. The exclusive formation of a single atropodiastereomer 12 in this critical step arises due to internal asymmetric induction, as planned. In addition, the first total synthesis of four other monomeric sarpagine indole alkaloids is described.

/pdf/nature-inspired-stereospecific-total-synthesis-of-p-17te20nldu.pdf

Nature-inspired stereospecific total synthesis of P-(+)-dispegatrine and four other monomeric sarpagine indole alkaloids.

General approach for the total synthesis of the sarpagine related indole alkaloids (+)-Na-methyl-16-epipericyclivine, (−)-alkaloid Q3 and (−)-panarine via the asymmetric Pictet–Spengler reaction

Based on the discovery of copper-catalyzed cyclopropanol ring-opening addition to iminium ions, an unprecedented catalytic aerobic C-H oxidation/cyclopropanol cyclization cascade using CuCl2 as the multifunctional catalyst and air as the oxidant was developed to construct the azabicyclo[3.3.1]nonane skeleton, which is widespread in natural products and medicines. Using this method, concise asymmetric total synthesis of the indole alkaloid (-)-suaveoline was achieved. This study not only provides an efficient, low-cost, and environmentally benign method for constructing such bridged frameworks, but also enriches the realm of cyclopropanol chemistry and C-H functionalization.

Minna Westersund

Papers

Chapter 2 – The Sarpagine Group of Indole Alkaloids