Unlock instant, AI-driven research and patent intelligence for your innovation.
Method for preparing optically active theanine by enzymatic method
What is Al technical title?
Al technical title is built by PatSnap Al team. It summarizes the technical point description of the patent document.
An optically active and enzymatic preparation technology, applied in the field of preparing D or L-theanine, achieves the effect of simple operation and guaranteed position specificity
Inactive Publication Date: 2011-08-31
NANJING TECH UNIV
View PDF22 Cites 0 Cited by
Summary
Abstract
Description
Claims
Application Information
AI Technical Summary
This helps you quickly interpret patents by identifying the three key elements:
Problems solved by technology
Method used
Benefits of technology
Problems solved by technology
However, the preparation process of the former requires the energy product ATP, and while catalyzing the synthesis of theanine from ethylamine and glutamic acid, an ATP regenerationsystem must be constructed; while the latter does not need to consume ATP, but is prone to various side effects such as hydrolysis and transpeptidation. reaction
There is no report on the preparation method of D-theanine
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more
Image
Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
Click on the blue label to locate the original text in one second.
Reading with bidirectional positioning of images and text.
Smart Image
Examples
Experimental program
Comparison scheme
Effect test
Embodiment 1
[0028] Embodiment 1: Synthesis I of carboxyethylhydantoin.
[0029] Dissolve L-glutamic acid (0.1mol) and potassiumcyanate (0.12mol) in water, and use 0.5mol·L -1 Potassiumhydroxide solution was used to adjust the pH to 9.0, and the reaction was stirred at 75°C for 2 hours to generate the intermediate product N-carbamoyl-glutamic acid. Add 0.5mol·L -1 Adjust the pH of the solution to 1-2 with hydrochloric acid, heat up to 100°C and heat to reflux for 0.5h, cool, filter and dry to obtain 14.6g of crude carboxyethyl hydantoin, which can be recrystallized with water to obtain white crystalline carboxyethyl hydantoin. 79.5%, m.p.179~181℃, 1 H NMR (DMSO-d6, 500MHz) δ: 12.14 (s, 1H, COOH), 10.59 (s, 1H, 3-NH), 7.91 (s, 1H, 1-NH), 4.03~4.00 (m, 1H, CH), 2.33~2.30(m, 2H, CH 2 ), 1.95~1.68 (m, 2H, CH 2 ); MS m / z: 171.1(M-1) - .
Embodiment 2
[0030] Example 2: Synthesis II of carboxyethylhydantoin.
[0031] Dissolve L-sodium glutamate monohydrogen (0.1mol) and sodiumcyanate (0.14mol) in water, and use 0.1mol·L-1 Sodiumhydroxide solution was used to adjust the pH to 8.5, and the reaction was stirred at 80°C for 2 hours to generate the intermediate product N-carbamoyl-glutamic acid. Add concentrated hydrochloric acid to adjust the pH of the solution to 1-2, raise the temperature to 100°C and heat to reflux for 1.5 hours, cool, filter and dry to obtain 15.3 g of crude carboxyethyl hydantoin, which can be recrystallized with water to obtain white crystal carboxyethyl hydantoin. Yield 82.7% (mp: 179-181°C).
Embodiment 3
[0032] Embodiment 3: the synthetic I of N-ethyl hydantoin propionamide.
[0033] Add carboxyethylhydantoin I (0.1mol) to 20mL DMF, stir at room temperature to dissolve, add DCC (0.1mol) and HOBt (0.1mol), react for 2 hours, remove DCU (dicyclohexylurea) by filtration, and take the filtrate. Ethylamine gas was introduced from a compressed gas cylinder to react overnight. Diethyl ether was added for extraction three times, and the extract was dried and concentrated to obtain a white solid. After recrystallization from methanol, 18.2 g of white crystal N-ethylhydantoinamide was obtained, with a yield of 91.4%, m.p.220-221°C, 1 HNMR (DMSO-d6, 500MHz) δ: 10.59 (s, 1H, 3-NH), 7.88 (s, 1H, 1-NH), 7.79 (s, 1H, NH), 4.03~4.00 (m, 1H, CH ), 3.06~3.03 (m, 2H, CH 2 ), 2.15~2.09 (m, 2H, CH 2 ), 1.89~1.72 (m, 2H, CH 2 ), 1.03~0.98 (m, 3H, CH 3 ); MS m / z: 198.1(M-1) - .
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More
PUM
Property
Measurement
Unit
specific rotation
aaaaa
aaaaa
Login to View More
Abstract
The invention discloses a method for preparing optically activetheanine by an enzymatic method. The method comprises the following steps: adopting cyanate and glutamic acid as raw materials, reacting under an alkali condition; acidizing and cyclizing to form carboxyethyl glycolylurea; then adopting a peptide connecting reagent to connect ethylamine to a carboxyl group at the tail end of the carboxyethyl glycolylurea and then extracting, concentrating, crystallizing and separating to obtain N-ethyl glycolylurea propionamide; using wet thalli containing glycolylurea enzymes and carbamyl enzymes as a catalyst and preparing L or D-theanine by catalyzing and hydrolyzing the N-ethyl glycolylurea propionamide under an alkalescent condition; and separating, concentrating and crystallizing the obtained theanine enzymatic conversion solution to obtain the L or D-theanine. In the method, both alpha-amino groups and carboxyl groups in glutamic acid are protected by adopting glycolylurea rings, and only gamma-carboxyl groups are exposed, thereby guaranteeing the position specifity of an ethylamine connecting reaction. The invention avoids most repeated protection and deprotection steps in chemosynthesis, has simple operation and reduces side reactions.
Description
technical field [0001] The invention relates to a method for preparing D or L-theanine by hydantoin enzymatic method. Background technique [0002] L-theanine is a special amino acid contained in tea leaves. Its structure is similar to glutamic acid, and it belongs to γ-glutamyl ethylamine derivatives. The average content of L-theanine in tea is 1-2%, accounting for more than 50% of the total amount of amino acids in tea. L-theanine can significantly promote the release of dopamine in the central nervous system of the brain and increase the physiological activity of dopamine, thereby helping to relax the body, relieve fatigue, and effectively control symptoms of depression (Peng Ying et al., CN03124680.X). Health care product manufacturers at home and abroad have developed and listed a variety of L-theanine-based medicines and / or health products for the preparation of treatment and / or depression (Chen Jiancao et al., CN200510200423.9); preparation of treatment and / or preven...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More
Application Information
Patent Timeline
Application Date:The date an application was filed.
Publication Date:The date a patent or application was officially published.
First Publication Date:The earliest publication date of a patent with the same application number.
Issue Date:Publication date of the patent grant document.
PCT Entry Date:The Entry date of PCT National Phase.
Estimated Expiry Date:The statutory expiry date of a patent right according to the Patent Law, and it is the longest term of protection that the patent right can achieve without the termination of the patent right due to other reasons(Term extension factor has been taken into account ).
Invalid Date:Actual expiry date is based on effective date or publication date of legal transaction data of invalid patent.
Login to View More