title: Weinreb amidation as the cornerstone of an improved synthetic route to A-ring-modified derivatives of luotonin A.
abstract: Weinreb amidation of ethyl 4-oxo-3,4-dihydroquinazoline-2-carboxylate with aromatic amines provides a significantly improved route to anilide-type key intermediates for the synthesis of the anticancer alkaloid, luotonin A, and new A-ring-modified derivatives thereof. This method has advantages concerning overall yield, brevity, and versatility with regard to the aromatic amine component, even if the latter has less favourable nucleophilicity, solubility and/or stability properties. This is demonstrated by the concise synthesis of a small library of luotonin A analogues, including a novel thiophene isostere of the alkaloid.
authors.affiliation: Department of Drug and Natural Product Synthesis, Faculty of Life Sciences, University of Vienna, Althanstraße 14, A-1090 Vienna, Austria. norbert.haider@univie.ac.at
authors.forename: Norbert
authors.initials: N
authors.lastname: Haider
authors.forename: Simon
authors.initials: S
authors.lastname: Nuß
mesh_terms: D003653:Decarboxylation; D006868:Hydrolysis; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry; D011809:Quinones / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D011758:Pyrroles; D011809:Quinones; C480761:luotonin A