6324-01-2Relevant articles and documents
Method for preparing p-hydroxyphenylglycine in pulse tubular reactor
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Paragraph 0029-0047, (2021/05/12)
The invention discloses a method for preparing p-hydroxyphenylglycine in a pulse tubular reactor, which is characterized in that glyoxylic acid, phenol and sulfamic acid are used as raw materials, p-hydroxyphenylglycine is prepared in a novel pulse tubular reactor in a nitrogen atmosphere, and the method belongs to the technical field of organic synthesis processes. Materials are introduced into the pulse tubular reactor through a metering pump and then subjected to preheating, mixing reaction and separation to obtain a p-hydroxyphenylglycine product, and compared with a process reported in literatures, the novel process has the advantages that the reaction time can be greatly shortened, the workshop efficiency can be improved, the reaction temperature can be accurately controlled, and the generation of by-products can be effectively reduced. And by introducing the novel pulse reactor, the mass and heat transfer effect of the reaction is qualitatively improved compared with that of a kettle type process, so that the use of a phase transfer catalyst is avoided, and the cost is saved. Compared with methods reported in literatures, the process technology has the advantages that the glyoxylic acid conversion rate, the product selectivity and the like are remarkably improved, and the existing outdated process technology can be replaced after the process technology is put into production.
Method for catalytically synthesizing p-hydroxyphenylglycine by using solid phosphoric acid
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Paragraph 0033-0036, (2022/01/08)
The invention relates to a method for catalytically synthesizing p-hydroxyphenylglycine by using solid phosphoric acid, the method comprises the following steps: respectively adding phenol, sulfamic acid and a solid phosphoric acid catalyst into an alkane solvent, and controlling the feeding mass ratio of the phenol to the sulfamic acid to the solid phosphoric acid catalyst to the alkane solvent to be 1: (1-1.2): (1.5-4): (5-15); heating and refluxing at the temperature of 70-100 DEG C, adding a glyoxylic acid aqueous solution with the mass fraction of 50% into a reaction solution within 0.5-2 hours, simultaneously separating moisture in reactants by azeotropic distillation, and continuously carrying out heat preservation reaction for 2-6 hours after charging is completed, so that glyoxylic acid in the reactants is completely converted; the content of the obtained DL-p-HPG product is 99.5%, and the molar yield of the obtained DL-p-HPG product is 75%-80%. The fly ash floating beads are used as a carrier and a synthesis promoter of the solid phosphoric acid catalyst, generation of phenolic polymer impurities is inhibited through immobilization of reaction raw materials, and DL-p-HPG synthesis selectivity is improved.
Synthesis of Unprotected 2-Arylglycines by Transamination of Arylglyoxylic Acids with 2-(2-Chlorophenyl)glycine
Inada, Haruki,Shibuya, Masatoshi,Yamamoto, Yoshihiko
, p. 11047 - 11059 (2020/10/12)
The transamination of α-keto acids with 2-phenylglycine is an effective methodology for directly synthesizing unprotected α-amino acids. However, the synthesis of 2-arylglycines by transamination is problematic because the corresponding products, 2-arylglycines, transaminate the starting arylglyoxylic acids. Herein, we demonstrate the use of commercially available l-2-(2-chlorophenyl)glycine as the nitrogen source in the transamination of arylglyoxylic acids, producing the corresponding 2-arylglycines without interference from the undesired self-transamination process.
Preparation method for D, L-phenylglycine and analogue thereof
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Paragraph 0021; 0022; 0025; 0026; 0029; 0030; 0033; 0034, (2017/03/17)
The invention provides a preparation method for D, L-phenylglycine and an analogue thereof. According to the method, benzaldehyde, an analogue thereof and hydrocyanic acid are adopted as raw materials and subjected to cyanidation reaction, and then 2-hydroxy-benzyl cyanide or 2-hydroxy-benzyl cyanide analogue (cyanohydrin for short) is generated. Cyanohydrin reacts with carbon dioxide and the aqueous solution of ammonia, and then 5-phenyl-hydantoin and an analogue thereof (hydantoin for short) are generated. hydantoin is successively subjected to steam stripping, alkaline hydrolysis, steam stripping, decolorization, neutralization, crystallization, washing, centrifuging, drying and the like to obtain D, L-phenylglycine and the analogue thereof. Compared with the prior art, the preparation method for D, L-phenylglycine and the analogue thereof can significantly and effectively reduce the pollution, and fewer inorganic salt by-products are generated. Meanwhile, the prepared D, L-phenylglycine and the analogue thereof are high in product yield and high in purity. Counted in benzaldehyde and the analogue thereof, the yield of D, L-phenylglycine and the analogue thereof is larger than or equal to 96%, and the product purity is larger than or equal to 99%. Meanwhile, the process flow is simple and feasible, so that the method is worthy of market popularization and application.
P-hydroxy-glycine preparation method (by machine translation)
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Paragraph 0022-0027, (2017/06/29)
The invention provides a method for the preparation of hydroxy-phenyl glycine, comprising the following steps: A synthetic hydroxy because benzene sea, B. Hydroxyphenyl hydantoin as a result of the hydrolysis, the present invention provides a preparation method, high efficiency, high output, suitable for large-scale mass production. (by machine translation)
Purification of amoxicillin trihydrate by impurity-coformer complexation in solution
Hsi, Kay Huai Ying,Concepcion, Anthony Joseph,Kenny, Meghan,Magzoub, Amna Ahmed,Myerson, Allan S.
, p. 6776 - 6781 (2013/09/02)
In this work, we demonstrated the purification of amoxicillin trihydrate (AMCT) by the formation of 4-hydroxyphenylglycine (4HPG)-coformer complex in solution. Without advanced knowledge of cocrystal formation of 4HPG, a workflow was established to choose
METHOD FOR THE PREPARATION OF D-p-HYDROXYPHENYLGLYCINE
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Page/Page column 6, (2009/12/02)
Method for the preparation of p-hydroxyphenylglycine enriched with the D- enantiomer (D-HPG), using an asymmetric transformation of a (racemic) mixture of the enantiomers of p-hydroxyphenylglycine (HPG) with the aid of D-bromocamphorsulphonic acid (D-BrCas) in the presence of a racemization agent, where a solid diastereomeric salt of D-HPG and D-BrCas is formed, and the asymmetric transformation is carried out in an aqueous medium and in the presence of inorganic salts. In a specially preferred embodiment, HPG is first prepared from glyoxylic acid, phenol and an amino group donor, and the resulting reaction mixture, which contains HPG and the inorganic salts, is then used in the asymmetric transformation as such. D-HPG is preferably added to the reaction mixture obtained in the asymmetric transformation.
9-BBN: An amino acid protecting group for functionalization of amino acid side chains in organic solvents.
Dent 3rd., William H,Erickson, W Randal,Fields, Stephen C,Parker, Marshall H,Tromiczak, Eric G
, p. 1249 - 1251 (2007/10/03)
9-Borabicyclononane (9-BBN) has been utilized to protect functionalized amino acids for potential chemoselective side chain manipulation. The 9-BBN group imparts organic solubility to otherwise hydrophilic molecules and is tolerant of a wide range of reaction conditions. The high degree of solubility of these molecules in THF is particularly noteworthy. It is cleaved with either aqueous HCl or by exchange with ethylenediamine in methanol. [reaction: see text]
The complestatins as HIV-1 integrase inhibitors. Efficient isolation, structure elucidation, and inhibitory activities of isocomplestatin, chloropeptin I, new complestatins, A and B, and acid-hydrolysis products of chloropeptin I
Singh,Jayasuriya,Salituro,Zink,Shafiee,Heimbuch,Silverman,Lingham,Genilloud,Teran,Vilella,Felock,Hazuda
, p. 874 - 882 (2007/10/03)
From the screening of a microbial extract library, isocomplestatin (1), a new axial-chiral isomer of complestatin (2) which is a known rigid bicyclic hexapeptide, was identified as a potent natural product inhibitor of HIV-1 integrase, a unique enzyme responsible for viral replication. Isocomplestatin showed inhibitory activities (IC50) in coupled 3′-end processing/strand transfer (200 nM), strand transfer (4 μM), and HIV-1 replication (200 nM) in virus-infected cells. Attempted large-scale isolation of 1 by the literature method, used for the isolation of complestatin, led to lower yield and limited availability. We have developed several new, two-step, high-yielding absorption/elution methods of isolation based on reverse-phase chromatography at pH 8 that are applicable to scales from one gram to potential industrial quantities. We have also discovered and determined the structure of two new congeners of 1, namely, complestatins A (4) and B (5), with almost equal HIV-1 integrase activity. They differ from 1 at C2′ and C3′ of the tryptophan moiety (residue F). Selective acid hydrolysis of chloropeptin I (3), itself a known acid-catalyzed rearranged isomer of 1 and 2 (8′- vs 7′-substitution in tryptophan residue F, respectively), an isomer of complestatin, and isocomplestatin resulted in a number of fragments (6-10) with retention of most of the HIV-1 integrase activity. The structure - activity relationship as revealed by these compounds could possibly lead to the design of better inhibitors or understanding of the HIV-1 integrase target.
Asymmetric Transformation of (RS)-2-Phenylglycine via Formation of Salt with (1S)-10-Camphorsulfonic Acid
Shiraiwa, Tadashi,Sakata, Shinji,Fujishima, Keiko,Kurokawa, Hidemoto
, p. 191 - 195 (2007/10/02)
An asymmetric transformation of (RS)-2-phenylglycine was carried out via formation of a salt with (1S)-10-camphorsulfonic acid in acetic acid, propanoic acid, or butanoic acid by heating at 100 deg C without using any catalysts such as aldehydes.The rate of epimerization of a more soluble salt of (S)-Phg with (S)-CS was estimated to be the lowest in acetic acid and highest in butanoic acid.The asymmetric transformation in propanoic acid, however, was achieved successfully to give the salt of (R)-Phg with (S)-CS with 100percent optical purity in 82percent yield.Optically pure (R)-Phg was obtained from the salt in 80percent yield based on the (RS)-Phg used as the starting material.