Saturated and unsaturated compounds having sweet, salt or umami taste enhancement qualities. The compounds have the structure: ##STR00001## where R.sup.1.dbd.H or methyl; R.sup.2 is selected from the group consisting of H, C1-C4 alkyl, alkenyl and methylene; R.sup.3 is selected from the group consisting of H, C1-C8 straight or branched chain alkyl, alkenyl, dienalkyl or phenyl; or if R.sup.1.dbd.H, R.sup.2 and R.sup.3 taken together can represent ##STR00002## cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl, cyclohexyl, or cyclohexenyl; R.sup.4 is selected from the group consisting of H, methyl and ethyl; R.sup.5 is selected from the group consisting of H, methyl and ethyl; R.sup.6 is selected from the group consisting of H, C1-C9 straight or branched chain alkyl, alkenyl, alkyldienyl, acyclic or containing no more than one ring; with the proviso that in structure 1 when R.sup.4 is H or Me; and R.sup.5.dbd.H or methyl, R.sup.6 may be selected from the group described above or phenyl.