496789-39-0Relevant academic research and scientific papers
Formal Total Synthesis of Diazonamide A by Indole Oxidative Rearrangement
David, Nadège,Pasceri, Raffaele,Kitson, Russell R. A.,Pradal, Alexandre,Moody, Christopher J.
, p. 10867 - 10876 (2016/07/27)
A short formal total synthesis of the marine natural product diazonamide A is described. The route is based on indole oxidative rearrangement, and a number of options were investigated involving migration of tyrosine or oxazole fragments upon oxidation of open chain or macrocyclic precursors. The final route proceeds from 7-bromoindole by sequential palladium-catalysed couplings of an oxazole fragment at C-2, followed by a tyrosine fragment at C-3. With the key 2,3-disubstituted indole readily in hand, formation of a macrocyclic lactam set the stage for the crucial oxidative rearrangement to a 3,3-disubstituted oxindole. Notwithstanding the concomitant formation of the unwanted indoxyl isomer, the synthesis successfully delivered, after deprotection, the key oxindole intermediate, thereby completing a formal total synthesis of diazonamide A.
Chemistry and biology of diazonamide A: First total synthesis and confirmation of the true structure
Nicolaou,Chen, David Y.-K.,Huang, Xianhai,Ling, Taotao,Bella, Marco,Snyder, Scott A.
, p. 12888 - 12896 (2007/10/03)
With the addition of a tenth ring, the exchange of an oxygen atom for a nitrogen in the heart of the molecule, and a different terminal residue, the revised architecture for diazonamide A (1) provided an even more challenging molecular puzzle for chemical synthesis than its predecessor. In this article, we detail the first successful total synthesis of diazonamide A, an endeavor which not only verified its proper connectivities and established the stereochemistry of its previously unassignable C-37 chiral center, but which also was attended by the development of several new synthetic strategies and tactics.
