Chemo- and regioselective modification of l-histidine with tertiary cyanopropargylic alcohols

Abstract

l-Histidine chemo- and regioselectively reacts with tertiary cyanopropargylic alcohols (4,4-di-alkyl-4-hydroxybut-2-ynenitriles) under mild conditions (water, 6.4 wt.% NaOH, 5—15 °C, 72—175 h) with the formation of new “unnatural” amino acids containing an iminodihydrofuran substituent in the amino group (50—70% yields).