Preparation of a Useful Synthetic Precursor, 2-Substituted 4(3H)-Quinazolinone: Directed Lithiation and N3-Deprotection of 3-t-Butoxycarbonyl-4(3H)-quinazolinone
摘要:
Directed lithiation of 3-t-butoxycarbonyl-4(3H)-quinazolinone using LDA was accomplished to afford 2-substituted 3-t-butoxycarbonyl-4(3H)quinazolinones. The t-butoxycarbonyl group of these products was easily deprotected to give key intermediates for the synthesis of quinazoline derivatives, 2-substituted 4(3H)-quinazolinones, in good yield.
Synthesis of Chrysogine, a Metabolite of Penicillium chrysogenum and some related 2-substituted 4-(3H)-Quinazolinones
作者:Jan Bergman、Anna Brynolf
DOI:10.1016/s0040-4020(01)86694-1
日期:1990.1
Syntheses of both enantiomers of chrysogine, 2-(α-hydroxyethyl)-4(3H)-quinazolinone, 1 from 2-ammobenzamide are reported. Thus reaction of 2-aminobenzamide and optically active α-acetoxypropionyl chloride gave 9, which upon saponification and cyclization induced by aqueous sodium carbonate at room temperature gave chrysogine. The enantiomeric purity of 1 was determined by NMR. Inversion of (-)-(S)-1