Synthetic Approach to the Natural N-Nitrosohydroxylamino Tetramic Acid JBIR-141

Abstract

An analogue of the Streptomyces metabolite JBIR-141, featuring a delicate N-nitrosohydroxylamine, a 3-acyltetramic acid, and an oxazoline, was synthesized by a convergent strategy from L-alanine, L-threonine, and L-glutamic acid. Key steps were the cyclization of an Ala−Thr derivative to give the oxazoline, a Dieckmann condensation affording the 3-acyltetramic acid, and the N-nitrosation of a hydroxylamino derivative of glutamic acid. An adequate protecting group strategy was established for coupling the three building blocks.Letter pubs.acs.org/OrgLett

Catalytic Amide Activation with Thermally Stable Molybdenum(VI) Dioxide Complexes

“…40,41 The Mo(VI) catalysis is more attractive in chemical synthesis due to its high selectivity eliminating unproductive side reactions and tolerating a diverse range of functional groups. [42][43][44][45] Additionally, the reaction Scheme 1. Azolines in natural products and applications in in target-oriented synthesis.…”