Synthesis and structure-activity relationships of 1-substituted 4-(1,2-diphenylethyl)piperazine derivatives having narcotic agonist and antagonist activity
Racemates and enantiomers of 1-substituted4-[2-(3-hydroxyphenyl)-1-phenylethyl]piperazine derivatives (3-18) were synthesized, and their analgesic and other pharmacological activities and structure-activity relationships were investigated. The S-(+) enantiomers of 2a, 5, 7, 9, 10, and 15-18 had a stronger analgesicactivity than their R-(-) enantiomers; analgesicactivity of the strongest one [(S)-(+)-10]