Patent ID: 8048926

Claim:
A compound of the general formula: wherein: *C denotes a chiral carbon with an S-configuration; R 1 and R 2 are each independently selected from the group consisting of hydrogen, alkyl having 1-30 carbon atoms, alkenyl having 1-30 carbon atoms, alkynyl having 1-30 carbon atoms, cycloalkyl, aryl, O-carboxy, C-carboxy, carbonyl, thiocarbonyl, O-carbamyl, O-thiocarbamyl and a fatty acid acyl, R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl having 1-30 carbon atoms, alkenyl having 1-30 carbon atoms, alkynyl having 1-30 carbon atoms, cycloalkyl, aryl, O-carboxy, C-carboxy, thiocarbonyl, O-carbamyl, O-thiocarbamyl and a fatty acid acyl, or, alternatively, R 1 and R 2 and/or R 3 and R 4 form a five- or six-membered ring; and R 5 and R 6 are each independently selected from the group consisting of hydrogen, cycloalkyl, aryl and phosphonyl, or a pharmaceutically acceptable salt thereof, with the proviso that when R 3 and R 4 are both hydrogen, R 1 and/or R 2 are not hydrogen, methyl or alkyl, and R 5 and/or R 6 are not hydrogen, the compound being characterized by high permeability through the blood brain barrier.