Synthesis of phosphinic acids on the basis of hypophosphites: VI. General methods for synthesis of pseudo-γ-glutamylpeptides
作者:V. V. Ragulin
DOI:10.1134/s1070363207050076
日期:2007.5
A general method for synthesis of 2-substituted pseudo-gamma-glutamylpeptides, namely, [2-(hydroxy-carbonyl)ethyl][3-amino-3-(hydroxycarbonyl)propyl]phosphinic acids I which are phosphinic acid analogs of,gamma-glutamylpeptides. Bis(trimethylsilyl) hypophosphite (IV) formed from ammonium hypophosphite (II) in situ was added to the respective ck-substituted acrylate to form bis(trimethylsilyl) [2-R-2-(alkoxycarbonyl)ethyl]phosphonites V. Treatment of compounds V in situ with excess dibromoethane followed by alcoholysis gave [2-R-2-( alkoxycarbon),I)ethyl](2-bromoethyl)phosphonic acids VI which without isolation were treated with excess triethyl orthoformate. The sirnultanious esterification and dehydrobrommation led to [2-R-2-( alkoxy-carbonyl)ethyl 1(vinyl)phosphinates III which were isolated and characterized. The Michael addition of diethyl acetamidomalonate to vinylphosphinates III followed by acid hydrolysis of phosphinates VII without their isolation resulted in formation of target [2-R-2-(hydi-oxycai-bonyl)ethyl][')-amino-3-(hydroxycarbonyl)]proyl]phosphinic acids-pseudo-gamma-glutamylpeptides I.