RT Journal Article SR Electronic T1 STUDIES OF MORPHINE, CODEINE AND THEIR DERIVATIVES XII. THE ISOMERS OF MORPHINE AND DIHYDROMORPHINE JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 421 OP 431 VO 56 IS 4 A1 NATHAN B. EDDY YR 1936 UL http://jpet.aspetjournals.org/content/56/4/421.abstract AB The general pharmacological activity of the isomers of morphine and dihydromorphine is described. In addition the activity of four groups of isomers in the morphine, codeine series, the structural relationships in each group being the same, is discussed in relation to the chemical modifications. It is suggested that the pharmacological relationships afford a basis for pairing the isomers, a pairing at present impossible by chemical means.