2 r 3 and r 4 are the same and are alkyls r is different from u2014 oh or u2014 o u2296 as regards other compounds known to be structurally and functionally similar the compounds of the present invention have the advantage of crossing the bbb more easily at the same time maintaining excellent levels of inhibition of the activity of cpt they are therefore able to inhibit the activity of cpt in the hypothalamus thus presenting the effects in the reduction in food intake as described above preferably r 1 is u2014 conhr 5 and r 5 is a linear or branched alkyl saturated or unsaturated containing between 7 and 20 carbon atoms the preferred r 5 groups are therefore selected among heptyl octyl nonyl decyl undecyl dodecyl tridecyl tetradecyl pentadecyl hexadecyl heptadecyl octadecyl nonadecyl and eicosyl depending on the meanings of the radicals a r 1 r 2 r 3 r 4 r 5 y and z in the compounds of formula i one or more chiral centres on carbon or nitrogen atoms may be present for the purposes of the present invention it is pointed out that each of the products of formula i can exist both as a racemic mixture ris and in the separate isomeric forms r and s the products of formula i in which a is u2014 n r 2 r 3 r 4 u2295 and r is different from u2014 oh and u2014 o u2296 can exist only as salts with pharmacologically acceptable anions these anions are here identified by the radical x u2212 the.