The Action of Alkalies on Peptides and on Ketopiperazines
نویسندگان
چکیده
1. The tripeptide glycyl-levo-alanyl-glycine in solution of either one or ten equivalents of alkali does not undergo racemization on standing. 2. The dipeptide levo-alanyl-glycine under the conditions given in (1) does not undergo racemization. 3. In ketopiperazines, levo-alanyl-glycine anhydride and in levo-prolyl-glycine anhydride under the influence of dilute alkalies, racemization takes place. 4. Racemization in the present experiments was never complete. The degree of racemization seems to depend, on the one hand, on the stability of the ketopiperazine ring; on the other, on the concentration of the alkali. 5. The significance of these observations will depend on the outcome of the work on a larger number of polypeptides and ketopiperazines. The work is now in progress in this laboratory.
منابع مشابه
The Action of Alkalies
In a previous communication I we reported on the action of weak and of stronger alkali on dextro-alanyl-dextro-alanine anhydride. I t was observed that the anhydride was partially racemized if it was allowed to remain in an aqueous solution containing one equivalent of sodium hydroxide for 24 hours. When the concentration of the alkali was increased tenfold, the anhydride was rapidly converted ...
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ورودعنوان ژورنال:
- The Journal of General Physiology
دوره 8 شماره
صفحات -
تاریخ انتشار 2003