Bräunungsreaktionen und fragmentierungen von kohlenhydraten : Teil III. über reaktionen des dihydroxyacetons mit aminen und áminosäuren

Abstract

Dihydroxyacetone reacts with primary amines at low temperature to form dimeric ketosylamines, which are stable only in the crystalline state at low temperatures. In the reaction of dihydroxyacetone with amino acids pyruvic aldehyde seems to be an important intermediate. This causes the Strecker degradation of amino acids to aldehydes. In contrast to other amino acids, glycine reacts with dihydroxyacetone to give small proportions of volatile carbonyl compounds, in which diacetyl predominates. Allomaltol is isolated as a by-product from the reaction of dihydroxyacetone with glycine, which leads primarily to melanoidins. In this case, the precursor of allomaltol, which is N-(2-methylpyron-4-yl-5)glycine, has been isolated. This compound was synthesised by melting allomaltol and glycine, and its structure proved by the preparation of derivatives.