Tocainide and related optically active chiral
![](/images/gifchars/alpha.gif)
-aminoanilides were synthesized and tested
in vivo via thehot plate test to evaluate their central analgesic action. The aims of the study were to verify if a
) the increasein lipophilicity, obtained by the introduction of an alkyl group on the steric center (
3f-i), and the replacementof the C=O group with the C=S (
10) group as well as the introduction of a methyl or ethyl group on theamidic nitrogen atom (
8a-c) would produce an increase in central analgesic efficacy with respect to Tocainide;b
) the 2,6-xylidide moiety is crucial for high analgesic activity (
3b-e); c
) the hydrogen atom bonded to theamidic nitrogen moiety is an essential pharmacophoric element for analgesic activity. Among all thesynthesized compounds,
3f showed antinociceptive properties with a good enantioselective index.