Thus, acylation of N-methylamides 38 with 2-azidobenzoyl chloride 37 (readily available from 2-azidobenzoic acid [142]) forms imides 39a-c, which upon treatment with triphenylphosphine (TPP) in the course of consecutive Staudinger reaction/intramolecular aza-Wittig reaction yield exclusively 3-methylquinazolin-4(3H)-ones 40a-c quantitatively (Scheme 4) [143,144]. This procedure provides simple and efficient quinazolinone annelation of amides and lactams.

The intramolecular iminocyclization of N-(2-azidomethylphenyl)succin-imide 41a and -glutarimide 41b proceeds cleanly with TPP to afford fused quinazolines 42a and 42b, respectively, in high yields (Scheme 5) [145]. On the other hand, the iminocyclization of 43b to 44b requires the use of TBP and heating at 140 °C. Reduction of the nitro group of 44b affords antitumor agent batracylin (NSC-320846) 44c (Scheme 5) [146].

A facile route to benzoannelated macrocyclic 1,4-diamines has been developed via quinazolinone annelation of lactams, followed by reductive ring

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