SEPARATION OF MORPHINE-LIKE EFFECTS BY OPTICAL RESOLUTION . LEVO ISOMERS AS STRONG ANALGETICS AND NARCOTIC ANTAGONISTS

l-and d-mandelie acids have been used in combination to separate enantiomers of α-(±)-5 methyl-(Ic) and-5-ethyl-2′-hydroxy-2-methyl-6,7-benzomorphans (Id); d-10-camphorsulfonic and d-mandelic acids were employed for the α-(±)-2,9-dimethyl-2′-hydroxy-5-propyl analog (Ie). In every instance, the levo isomers were twice as potent, analgetically, as the racemates but would not suppress abstinence symptoms in morphine dependent rhesus monkeys; in fact, they were nalorphine-like. The dextro isomers were weak analgetics (codeine like or less active), but, curiously, had low, intermediate, or high physical dependence capacity in monkeys, similar to the pattern seen with the dimethyl and diethyl honmlogs reported. © 1969, American Chemical Society. All rights reserved.