Apparent Degradation of Wool by Diazomethane Solutions

Abstract

THE action of diazomethane on proteins has been studied by a number of workers, who report that both O- and N-methylation occur. There is apparently no fission of the peptide chains, although it is stated¹ that the action of diazomethane on insulin causes a decrease in the cystine content. On the other hand, Kirst² claims that the cystine bridges in wool are unaffected by the reagent, and Herzig and Landsteiner³ state that wool is rather more resistant to diazomethane than are other proteins. In most of this earlier work, it was specifically stated that dry proteins and dry ethereal solutions of diazomethane were used. Recently, Kuhn and Ruelius⁴ have shown that diazomethane acts on aqueous solutions of peptides with formation of the corresponding betaines, while serum albumin and ovalbumin in water are slowly converted to insoluble products. We have now found that wool can be extensively degraded by ethereal diazomethane solutions, the product being almost completely soluble in water. The diazomethane, prepared from nitrosomethylurea, is added to the wool over a period of several days, together with small quantities of water. The soluble product contains no sulphur, and diffuses through ‘Cellophane’, while the appearance of the wool during the reaction closely resembles that of wool treated with strong alkali.