Weinreb Amidation as the Cornerstone of an Improved Synthetic Route to A-Ring-Modified Derivatives of Luotonin A

Molecules

Norbert Haider¹ 

关键词: Weinreb amidation;    luotonin A;    [4+2] cycloaddition;    thiophene;   

DOI  :  10.3390/molecules171011363

来源: mdpi

【 摘 要 】

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.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.