- A novel strategy for efficient chemoenzymatic synthesis of D-glutamine using recombinant Escherichia coli cells
-
D-glutamine is a D type stereoisomer of glutamine which is involved in many metabolic processes. Seeking lower-cost and industrially scalable approaches for the synthesis of D-glutamine is very valuable both in academic career and potential applications. Herein, we developed a novel efficient chemoenzymatic strategy for producing D-glutamine. Initially, DL-glutamine was chemically prepared with cheap and accessible DL-glutamic acid as raw material. Subsequently, the L-glutamine among the racemic mixture was selectively hydrolyzed to L-glutamic acid by Escherichia coli whole-cell system which expressed L-aminopeptidase D-Ala-esterase/amidase (DmpA) from Ochrobactrum anthropi. The left D-glutamine was obtained by isoelectric point precipitation with 70% of the theoretical yield. Furthermore, we optimized enzymatic resolution conditions to determine the optimum parameters as pH 8, 30 °C, 0.1% (v/v) Triton X-100, and 1 mM Mn2+. These results suggested that our strategy might be potentially usable for the synthesis of D-glutamine in industrial productions.
- Du, Qinglin,Zhang, Xiangyang,Pan, Xinru,Zhang, Hongjuan,Yang, Yu-Shun,Liu, Junzhong,Jiao, Qingcai
-
-
- CRYSTALLINE FORMS OF THALIDOMIDE AND PROCESSES FOR THEIR PREPARATION
-
The present invention relates to crystalline forms of thalidomide having a high polymorphic purity and to processes for their preparation. The present invention also relates to pharmaceutical preparations comprising the crystalline forms for the treatment of patients suffering from autoimmune, inflammatory or angiogenic disorders.
- -
-
Page/Page column 24-25
(2012/01/05)
-
- Radiosynthesis of 13N-labeled thalidomide using no-carrier-added [13N]NH3
-
Recent studies revealed that thalidomide (1) has unique and broad pharmacological effects on multi-targets although the application of 1 in therapy is still controversial. In this study, we synthesized nitrogen-13-labeled thalidomide ([13N]1) as a potential positron emission tomography (PET) probe using no-carrier-added [13N]NH 3 as a labeling agent. By use of an automated system, [ 13N]1 was prepared by reacting N-phthaloylglutamic anhydride (2) with [13N]NH3, following by cyclization with carbonyldiimidazole in a radiochemical yield of 56±12% (based on [ 11N]NH3, corrected for decay) and specific activity of 49±24GBq/μmol at the end of synthesis (EOS). At EOS, 570-780MBq (n=7) of [13N]1 was obtained at a beam current of 15 μA after 15 min proton bombardment with a synthesis time of 14 min from the end of bombardment. Using a small animal PET scanner, preliminary biodistribution of [ 13N]1 in mice was examined. Copyright
- Kumata, Katsushi,Takei, Makoto,Ogawa, Masanao,Yui, Joji,Hatori, Akiko,Suzuki, Kazutoshi,Zhang, Ming-Rong
-
experimental part
p. 53 - 57
(2010/09/14)
-
- PROCESSES FOR THE PREPARATION OF THALIDOMIDE
-
The present invention provides a process for the preparation of thalidomide (I) comprising: i) reacting a compound of formula (II), where one of R represents -OH or -NH2 and the other of R represents -NH2 or -OH, respectively, with a phthaloylating agent in the presence of a base and a a non-polar organic solvent to obtain a phthaloyl derivative where R have the same meanings as above; and ii) dehydrating the phthaloyl derivative using a dehydrating agent selected from an acid anhydride, an acid halide, an ion exchange resin or a molecular sleve to obtain thalidomide (I).
- -
-
Page/Page column 12-15
(2009/08/14)
-
- AN IMPROVED PROCESS FOR THE PREPARATION OF THALIDOMIDE
-
An improved process for the preparation of Thalidomide a TNF-alpha inhibitor by the conversion of N-phthaloyl L-glutamine in presence of an active ingredient of inorganic acid salts such as 1,1-Carbonyldi(1,2,4-triazole) as a condensing agent.
- -
-
Page/Page column 5
(2008/06/13)
-
- Hydrolyzed metabolites of thalidomide: Synthesis and TNF-α production-inhibitory activity
-
Putative hydrolyzed metabolites of thalidomide were prepared and characterized, and their inhibitory activity on tumor necrosis factor (TNF)-α production in the human monocytic leukemia cell line THP-1 was evaluated. α-(2-Carboxybenzamido)glutarimide was a more potent TNF-α production inhibitor than thalidomide.
- Nakamura, Takanori,Noguchi, Tomomi,Miyachi, Hiroyuki,Hashimoto, Yuichi
-
p. 651 - 654
(2008/02/08)
-
- Process for the synthesis of thalidomide
-
The invention relates to a process for the preparation of thalidomide (I) ???comprising the reaction between glutamine (II) ???and a phthaloylating agent, preferably phthalic anhydride, to give N-phthaloyl-glutamine, which is directly transformed in thalidomide.
- -
-
Page/Page column 5/7
(2008/06/13)
-
- A concise two-step synthesis of thalidomide
-
A two-step synthesis of thalidomide is presented. The sequence requires no purifications. Treatment of L-glutamine with N-carbethoxyphthalimide produces N-phthaloyl-L-glutamine. Cyclization of N-phthaloyl-L-glutamine to afford thalidomide is accomplished by treatment with CDI in the presence of a catalytic amount of DMAP.
- Muller, George W.,Konnecke, William E.,Smith, Alison M.,Khetani, Vikram D.
-
p. 139 - 140
(2013/09/08)
-
- Chiral inversion and hydrolysis of thalidomide: Mechanisms and catalysis by bases and serum albumin, and chiral stability of teratogenic metabolites
-
The chiral inversion and hydrolysis of thalidomide and the catalysis by bases and human serum albumin were investigated by using a stereoselective HPLC assay. Chiral inversion was catalyzed by albumin, hydroxyl ions, phosphate, and amino acids. Basic amino acids (Arg and Lys) had a superior potency in cataLyzing chiral inversion compared to acid and neutral ones. The chiral inversion of thalidomide is thus subject to Specific and general base catalysis, and it is suggested that the ability of HSA to catalyze the reaction is due to the basic groups of the amino acids Arg and Lys and not to a single catalytic site on the macromolecule. The hydrolysis of thalidomide was also base-catalyzed. However, albumin had no effect on hydrolysis, and there was no difference between the catalytic potencies of acidic, neutral, and basic amino acids. This may be explained by different reaction mechanisms of the chiral inversion and hydrolysis of thalidomide. Chiral inversion is deduced to occur by electrophilic substitution involving specific and general base catalysis, whereas hydrolysis is thought to occur by nucleophilic substitution involving specific and general base as well as nucleophilic catalysis. As nucleophilic attack is sensitive to steric properties of the catalyst, steric hindrance might be the reason albumin is not able to catalyze hydrolysis. 1H NMR experiments revealed that the three teratogenic metabolites of thalidomide, in sharp contrast to the drug itself, had complete chiral stability. This leads to the speculation that, were some enantioselectivity to exist in the teratogenicity of thalidomide, it could result from fast hydrolysis to chirally stable teratogenic metabolites.
- Reist, Marianne,Carrupt, Pierre-Alain,Francotte, Eric,Testa, Bernard
-
p. 1521 - 1528
(2007/10/03)
-