J. R. Bailey, W. T. Read
1914 Journal of the American Chemical Society  
I747 of silver in solution precipitated as sulfide by hydrogen sulfide. The solution was then boiled to remove all free hydrogen sulfide and the silver sulfide separated by filtration. The sulfuric acid was then separated by precipitation as sulfate with barium hydroxide and the excess of barium precipitated as carbonate by saturating the solution with carbon dioxide. The neutral solution was then concentrated and cooled, when the nucleoside separated in prismatic crystals. This pyrimidine was
more » ... his pyrimidine was purified for analysis by crystallization from hot water and separated on cooling, in small plates. On heating in a capillary tube the pyrimidine began to show signs of melting at about 240' and then decomposed quite sharply a 254'. This decomposition point varies according to the rate of heating. The yield of purified nucleoside was 0.6 g. They did not possess a sharp melting point. Calc. for C~H B O~N~: N, 19.72. Found: N, 19.42. The structure of this nucleoside was established by its behavior on reduction with hydriodic acid, NH-CO I I I II The Formation of 4-Methyluraci1, CO CH .-Five-tenths of a gram of the nucleoside was dissolved in 15 cc. of hydriodic acid (sp. gr. 1.7) and about 0 . 1 g. red phosphorus added to the solution. The solution was then boiled for 4 hrs., diluted with water and finally filtered to remove the phosphorus. The halogen and phosphate radicals were then removed by digesting with an excess of silver carbonate. After filtering, the excess of silver was then precipitated as sulfide with hydrogen sulfide and the aqueous solution then decolorized by boiling with bone-coal. The solution was then concentrated and cooled, when 4-methyluracil deposited in colorless crystals. It was purified by recrystallization from hot water. It did not melt or undergo decomposition below 300' and when mixed with pure 4-methyluracil this behavior, on heating, was not altered. NH-C.CHs , Calc. for C~H , O~N~: N, 2 2 . 2 2 . Found: N, 21.9. NEW HAVEN, CONN.
doi:10.1021/ja02185a015 fatcat:eqldqxlymzdkbilm2qzmm6qcpm