アヘンアルカロイドの分析 (第6報)

テバインの新呈色反応とその比色定量への応用

抄録

Heating of thebaine with dil. hydrochloric acid, followed by addition of 4-amino-antipyrine and potassium ferricyanide, and basification of this mixture with ammonia results in red coloration, the color changing to reddish brown on heating to 100°. The limit of detection by spot reaction is 4γ/0.05cc. Presence of morphine, codeine, narcotine, and papaverine does not interfere in this reaction as these alkaloids do not undergo coloration. By utilization of this coloration reaction, colorimetric determination of thebaine can be made in the presence of morphine, codeine, narcotine, and papaverine. The procedure of the colorimetry is as follows: One cc. of the test solution (aqueous solution of thebaine salt containing 40-310γ/cc. of thebaine) is placed in a 10-cc. measuring flask, 1cc. of 7% hydrochloric acid is added, and the mixture is warmed in a boiling-water bath for 25 minutes. When cooled, 1.5cc. of 0.5% 4-aminoantipyrine solution and 0.6cc. of 1% potassium ferricyanide solution are added and the mixture is shaken. After exactly 1 minute, 2cc. of 10% ammonia water is added, shaken again, and warmed in a boiling-water bath for 5 minutes. The mixture is cooled with tap water to room temperature, diluted with 1cc. of ethanol and water to make 10cc., and absorbance of the solution is measured at 435mμ. Blank test is carried out with the same reagents and in a same manner using 1cc. of water in place of the test solution.