| 摘要 |
Guaiacol is heated with iodoform, preferably in the proportions of 1,2 : 1 by weight, and the bye-products and unchanged starting materials removed by distillation or extraction with solvents. The product, which possesses therapeutic properties, may be purified by treatment with aqueous solutions of weak alkalies, preferably alkali carbonates and bicarbonates and in order of increasing alkalinity, and further purified by extraction with aqueous alkali bisulphite. According to the examples: (1) guaiacol and iodoform in the proportions by weight of 2,5 : 1 are heated together for some days at 105 DEG C. until no more methyl iodide is evolved and then distilled in vacuo; (2) guaiacol and iodoform in the proportions by weight of 1,2 : 1 are condensed as in (1) and the mass subjected to distillation in vacuo, steam distillation or solvent extraction; (3) the product of (1) or (2), if desired after dissolution in acetone, is heated with sodium carbonate solution with exclusion of air and acid then added to precipitate the purified compound ; alternatively, the starting material is extracted at ordinary temperature first with sodium bicarbonate solution and then with sodium carbonate solution and the solutions acidified, or the starting material is extracted in a nitrogen atmosphere with caustic soda solution and carbon dioxide then passed into the filtrate to separate the purified compound; (4) the product of (3) is twice extracted with sodium bisulphite solution and the precipitate formed on acidification extracted with ethyl acetate. The Specification as open to inspection under Sect. 91 also contains examples which describe the interaction by prolonged heat treatment of iodoform and guaiacol in the proportions by weight of 1 : 5 and 1 : 1 respectively. A further example is given according to which the reaction mixture of iodoform and guaiacol in the proportions by weight of 1 : 1,2, after prlonged heating is stirred into hot toluene, when a resinous product separates out. This subject-matter does not appear in the Specification as accepted.
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