The present invention refers to coumarin ethers of the formula (I), wherein R.sup.1 is H, OH or (E)-3-methyl-but-2-enyl, R.sup.2 is selected from the group consisting of methyl, 3-(4,5-dihydro-5,5-dimethyl-4-furanon-2-yl)-2-(E/Z)-butenyl, (E/Z)-3,7-dimethylocta-2,6-dienyl, 7-hydroxy-3,7-dimethyl-2-octen-6-on-yl and (E/Z, E/Z)-1-acetyl-oxy-3,7,11,11-tetramethyl-undeca-2,7-dien-10-on-y- l, R.sup.3 is H, R.sup.1 and R.sup.2O together for the group --O--C(C(.dbd.CH.sub.2)CH.sub.3)H--CH.sub.2--O-- or the group --C(H).dbd.C(H)--C(CH.sub.3).sub.2--O-- or R.sup.2O and R.sup.3 together form the group --O--C(H)(C(CH.sub.3).sub.2(H)--O--C(O)CH.sub.3)--CH.sub.2--, preferably to obliquin, for use as medicaments, especially for the treatment and/or prevention of disorders connected to impaired neurotransmission, as well as to dietary and pharmaceutical compositions and plant extracts containing such coumarin ethers and their uses.