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°C。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°C。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（α）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°C. The B theanine synthesized from L-PCA shapes as cabbage leaves with curved borders under SEM and with a m. p. of 217 - 218°C 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 (α) of 100% L- theanine was + 8.57°.
[1] Sakato Y.The chemical constituents of tea: III, A new amide, theanine[J]. J. Agric. Chem. Soc. Jap., 1950, 23: 262-267.
[2] Kito M, KoKura H, Izaki J, Sasaoka K. Theanine, a precusor of the phloroglucinol nucleus of catechins in tea plants[J]. Phytochem., 1968, 7:599-603.
[3] Takeo T.Biosynthesis of ethylamine in tea plant[A]. The Proceedings of the IV Int. Cong. of Food Sci. and Techn[C]. Ia, 1974, 55-57.
[4] Anan T, Amano I., Nakagawa M.Relation between changes of chemical. compositions and taste of green tea: I. Changes in contents of some ingredients during heating of green tea[J]. J. Jap. Soc. Food Sci. Technol., 1981, 28: 74-78.
[5] Hara T.Volatile compounds formed on roasting L-theanine with D-glucose[J]. J. Agric. Chem. Soc. Jap., 1981, 55: 1069-1072.
[6] Nakagawa M, Anan T, Ishima M.Relationship of green tea taste to chemical Composition[J]. Bull. Nat. Res. Inst. Tea, 1981, 17: 69-123.
[7] Yan S H, Meurens M, Dufour J P.Taste quality control of china tea by NIRS method[A]. The Proceeding of 2d Int. Cong, Edited by Iwamoto, M. & Kawano, S., Japan Korin Pub Co ed (Japan), 1990, 1: 66-173.
[8] Sadzuka Y, Sugiyama T, Miyagishima A, Nozawa Y, Hirota S.The effects of theanine, as a novel biochemical modulator on the antitumor activity of adeiamycin[J]. Cancer-letters, 1996, 105(2): 203-209.
[9] Sadzuka Y, Sugiyama T, Sonobe T.Improvement of idarubicin induced antitumor activity and bone marrow suppression by theanine, a component of tea[J]. Cancer-letters, 2000, 158(2), 119-124.
[10] Sugiyama T, Sadzuka Y, Tanaka K, Sonobe T.Inhibition of glutamate transporter by theanine enhances the therapeutic efficacy of doxorubicin[J]. Toxicology-letters, 2001, 121(2), 89-96.
[11] Menozzi A Appiani G, 1892 Sopra un nuovo acido derivato dal glutammico. Gazz. Chim. Ital., 22, 105-108.
[12] Menozzi A, Appiani G, 1892 Sopra alcuni derivati dell’acido glutammico: acidi piroglutammici e piroglutammidi.Gazz. Chim. Ital., 24, 370-391.
[13] Abderhalden E, Kautzsch K, 1910 Zur kenntnis der glutaminsäure und der Pyrrolidoncarbonsäure.Physiol. Chem., 68, 447-459.
[14] Beecham A F, 1954 The action of ammonia and other bases on γ-methyl and γ- ethyl L-glutamate.J. Am. Chem. Soc., 76, 4615.
[15] Lichtenstein N, 1942 Preparation of γ-alkylamides of glutamic acid.J. Am. Chem. Soc., 64, 1021-1022.
[16] Sakato Y, Hashizume T, Kishimoto Y, 1950 The chemical constituents of tea: V, Synthesis of theanine,J. Agric. Chem. Soc. Jap., 23, 269-271.
[17] Kawagishi H, Sugiyama K, 1992 Facile and large-scale synthesis of L- theanine. Biosci. Biotech. Biochem., 56,(4) 689.
[18] Marfey P, 1984 Determination of D-amino acids: II, Use of a bifunctional reagent, 1,5-difluoro-2,4-dinitrobenzene.Carlsberg Res. Commun., 49, 591-596.
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