アヘンアルカロイドの分析研究 (第11報)

Abstract

Oxidation of codeine and morphine with ceric ammonium nitrate and application of 2, 4-dinitrophenylhydrazine results in orange-red coloration. Thebaine, narcotine, and papaverine color yellowish to this reaction and can therefore be discriminated from the former two. Limit of detection is 1.5γ/0.05cc. In quantitative determination, interfering thebaine, narcotise, and papaverine must be removed. The procedure for determination of codeine is as follows: One cc. of aqueous solution of codeine (30-240 γ/cc.) is placed in a 5-cc. measuring flask, 2cc. of water is added, and the mixture is allowed to stand in crushed ice (0 to 2°) for 5 minutes. To this solution, 1cc. of 0.6% ceric ammonium nitrate (in N sulfuric acid), which had been stood in crushed ice for 5 minutes, is added, mixed well, and allowed to stand at that temperature for 25 minutes. To this mixture, 0.5cc. of 0.6% 2, 4-dinitrophenylhydrazine solution is added, the flask is removed from the ice bath, and allowed to stand at room temperature for 20 minutes. The mixture is diluted to 5cc. with water, shaken well, and transferred to a glass-stoppered centrifuge tube. Ten cc. of isoamyl acetate is added to the tube, shaken 100 times, and centrifuged for 3 minutes. Isoamyl acetate layer is discarded, 5cc. of fresh isoamyl acetate is added, and treated in the same manner. Absorbancy of the aqueous layer is measured at 500mμ. A blank test is carried out with the same reagent and in the same manner, using 1cc. of water in place of the test solution, and used as the control.In the presence of thebaine, the test solution is heated with N hydrochloric acid, basified with sodium hydroxide, and shaken with chloroform to transfer codeine into the chloroform layer.In the presence of narcotine and papaverine, the test sample is dissolved in 0.2% tartaric acid, shaken with chloroform, and the aqueous layer is submitted to determination of codeine as above.