TY - JOUR T1 - THE RESPIRATORY EFFECTS OF MORPHINE, CODEINE, AND RELATED SUBSTANCES VIII. THE EFFECT OF SUBSTITUTIONS ON CARBON-14 JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 229 LP - 245 VL - 73 IS - 3 AU - MARGARET SUMWALT AU - HARRY R. OSWALD Y1 - 1941/11/01 UR - http://jpet.aspetjournals.org/content/73/3/229.abstract N2 - A comparative study of 14 derivatives of morphine leads to the conclusion that the radical substituted at carbon-14 has some part in determining power to depress the respiration of rabbits. The hydroxyl group was not consistent in its influence. Its replacement by hydrogen augmented strength in some instances, reduced it in others. Its replacement by bromine produced a drug entirely lacking in depressant influence upon respiration. Muzzling it with an acetyl group made a drug with increased power for depressing respiration, as it does at carbon-6. The three drugs containing an acetoxyl group attached at carbon-14 were stronger depressants than any corresponding compounds with a different radical in that position. The respiratory effects upon rabbits of 9 of these substances are given for the first time in this paper. ER -