940950-82-3Relevant academic research and scientific papers
Biomimetic Synthesis of Urukthapelstatin A by Aza-Wittig Ring Contraction
Schwenk, Sebastian,Ronco, Cyril,Oberheide, Ansgar,Arndt, Hans-Dieter
, p. 4795 - 4799 (2016)
Marine bacteria produce highly cytotoxic polyheterocyclic cyclopeptide natural products by ribosomal peptide biosynthesis. Among them, urukthapelstatin A features a chain of five 2,4′-connected azole rings within a cyclo-octapeptide framework. We report a novel synthesis design that uses only α-amino acids as starting materials that leads to an efficient and stereoselective total synthesis of urukthapelstatin A. Kinetically favored macro-thiolactonization and high-yielding aza-Wittig heterocyclization to contract the macrocycle were crucial for success. These investigations additionally uncovered the unsuspected configurational lability of the embedded enamide substructure in solution.
Peptide-embedded heterocycles by mild single and multiple aza-Wittig ring closures
Riedrich, Matthias,Harkal, Surendra,Arndt, Hans-Dieter
, p. 2701 - 2703 (2008/02/14)
Ring a ring o'azoles: The aza-Wittig cyclization of amino acids and peptides is extremely mild, selective, and versatile. The reaction of amino acid esters and amino acid thioester azides delivers peptidic 1,3-azolines and 1,3-azoles with unsurpassed func
