高纯度茶氨酸的合成与特性(英文)

Synthesis and Characterization of Highly Pure Theanine

报道了一种改进的茶氨酸(γ-谷酰基乙胺)的合成方法,包括L-谷氨酸的去氢成为吡咯烷酮羟酸(PCA),然后再加纯的乙胺(99%,气-液)反应,得率92.6%,再在84%乙醇溶液中重结晶后,高纯度茶氨酸(A型) 的得率37.4%。其结晶在透视和扫描电镜下呈长方形棱柱,具丝光状。A型茶氨酸的融点为224℃。B型茶氨酸从L-PCA合成,为甘蓝叶状,边缘呈波浪型,融点217—218℃。用HPLC分析证明,A和B型茶氨酸是混合异构体,A型含47.9%的L-茶氨酸,B型含90.9%的L-茶氨酸,100%的L-茶氨酸的旋光度(á)为+8.57 。

An improved synthesis method of L-Theanine, γ glutamylethylamide was reported as the dehydratation of L-glutamic acid to pyrrolidone carboxylic acid (PCA), then PCA reaction with absolute ethylamine (99%, gas-liquid) with the yield of 92.6%. After re-crystallization in 84% ethanol solution the highest pure theanine (A type) is obtained with a yield of 37.4%. The crystals appear as tetra-rectangular prisms with a silk luster under transmission and scanning electron microscopy (TEM and SEM). The melting point of A theanine is 224℃. The B theanine synthesized from L-PCA shapes as cabbage leaves with curved borders under SEM and with a m. p. of 217 - 218℃ as reference data. By using HPLC, it is confirmed that A and B theanine are mix-isomers. The A theanine consists of 47.9% L-theanine and the B theanine consists of 90.9% L-theanine. The rotation (á) of 100% L- theanine was + 8.57 .