Work

Concise total synthesis of (+)-bionectins A and C

Year: 2013

Type: article

Abstract: The concise and efficient total synthesis of (+)-bionectins A and C is described. Our approach to these natural products features a new and scalable method for erythro-β-hydroxytryptophan amino acid synthesis, an intramolecular Friedel–Crafts reaction of a silyl-tethered indole, and a new mercaptan reagent for epipolythiodiketopiperazine (ETP) synthesis that can be unravelled under very mild conditions. In evaluating the impact of C12-hydroxylation, we have identified a unique need for an intramolecular variant of our Friedel–Crafts indolylation chemistry. Several key discoveries including the first example of permanganate-mediated stereoinvertive hydroxylation of the α-stereocenters of diketopiperazines as well as the first example of a direct triketopiperazine synthesis from a parent cyclo-dipeptide are discussed. Finally, the synthesis of (+)-bionectin A and its unambiguous structural assignment through X-ray analysis provides motivation for the reevaluation of its original characterization data and assignment.

Source: Chemical Science

DOI: 10.1039/c3sc51150b

Authors: Alexis Coste, Justin Kim, Timothy C. Adams, Mohammad Movassaghi

Institution: Massachusetts Institute of Technology

Language: English

Topic: Synthesis of Indole Derivatives

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funders: National Science Foundation, National Institutes of Health, National Defense Science and Engineering Graduate, National Institute of General Medical Sciences

Award: Synthesis and Study of Cyclotryptamine and Diketopiperazine Alkaloids