Synthesis of analogues of γ-aminobutyric acid. Part 11. Unsaturated and saturated tetronic acid [furan-2,4(3H,5H)-dione] derivatives

Abstract

5-(2-Aminoethylidene)-4-hydroxyfuran-2(5H)-one (3) and the corresponding reduced 5-(2-aminoethyl) derivative (4) have been synthesised as conformationally restricted analogues of the neurotransmitter GABA. The use of the t-butyl protected reagents bis(t-butoxycarbonyl) amine and 5-ethylidene-4-t-butoxyfuran-2(5H)-one (7b) allowed generation of the required amino compounds under mild acidic deprotection conditions in the final step.