A convenient and one-pot synthesis of tetracyclic isoindolo [1,2-a]quinazoline derivatives via Lewis acid mediated sequential C–N bond formation reactions is reported.
A straightforward synthesis of a-keto amides by coupling primary amines with aryl dibromoethanones under oxidative amidation conditions has been developed. The a-keto amides were then subjected to heterocyclodehydration reaction under BischlerNapieralski conditions followed by aromatization with DBU provided 1-benzoyl isoquinolines in a two-stage process. Utilizing this methodology, isoquinoline alkaloids such as thalmicrinone, papavaraldine, and pulcheotine A were synthesized in excellent yields.
The first total synthesis of the α‐oxo amide‐based natural product, N‐(3‐guanidinopropyl)‐2‐(4‐hydroxyphenyl)‐2‐oxoacetamide (3), isolated from aqueous extracts of hydroid Campanularia sp., has been achieved. The α‐oxo amide 12, prepared via the oxidative amidation of 1‐[4‐(benzyloxy)phenyl]‐2,2‐dibromoethanone (9a) with 4‐{[(tert‐butyl)(dimethyl)silyl]oxy}butan‐1‐amine (10a), has been used as the key intermediate in the total synthesis of 3 as HBr salt. On the way, an expeditious total synthesis of polyandrocarpamide C (2c), isolated from marine ascidian Polyandrocarpa sp., was carried out in four steps.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.