2-Benzyl-3-thiopropionic acid amide derivs. of formula (I) and (II) [X=H, C1-3 alkyl, or alkoxy, F, Cl, Br, CF3; R=H or C1-3 alkyl; n=1- 4; m=0-2; R1=C1-3 alkyl!, having R or S absolute configuration at 2 position, were prepd. Thus, BzSCH2CH(CH2Ph)CO2H was converted into the acid chloride, treated with (S)-MeSCH2CH2CH(NH2)CH2OH, and the diastereomers sepd. and hydrolyzed to give (S)- MeSCH2CH2CH[NHCOCH(CH2Ph)!CH2SH-(R) and -(S)CH2OH. (I) and (II) are CNS compds., esp. analgesics and anticonvulsants, propably because they are inhibitors of the enzyme encephalinase.
PROCESS FOR THE PREPARATION OF ENKEPHALINASE ENZYME INHIBITING COMPOUNDS