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Preparation and Evaluation of Poly-γ-Glutamic Acid Hydrogel Mixtures with Basic Drugs or Acidic Drugs: Effect on Ease of Swallowing and Taste Masking 被引量:1
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作者 Honami Kojima Saeri Ikegami +6 位作者 Shiho Nakamura Haruka Nishikawa Tamami Haraguchi Miyako Yoshida Minoru Ozeki Ikuo Kawasaki Takahiro Uchida 《Pharmacology & Pharmacy》 2019年第10期427-444,共18页
The purpose of this study was to prepare a poly-γ-glutamic acid hydrogel (PGA gel), to examine its ease of swallowing using texture profile analysis (TPA) and to evaluate its taste-masking effects on basic or acidic ... The purpose of this study was to prepare a poly-γ-glutamic acid hydrogel (PGA gel), to examine its ease of swallowing using texture profile analysis (TPA) and to evaluate its taste-masking effects on basic or acidic drugs using the artificial taste sensor. Using TPA, 0.5% and 1.0% PGA gels, 0.5% and 1.0% agar and 1.0% ι-carrageenan in the absence of drug was examined the hardness, adhesiveness and cohesiveness, ranked according to permission criteria published by the Japanese Consumers Affairs Agency. 0.5% PGA gel and 1.0% agar were classified into grade II. In the taste sensor measurement, the bitterness suppressions by 0.5% PGA gel were larger than that by 1.0% agar in all drugs and the bitterness suppressions of basic drugs in 0.5% PGA gel were more potent than those of acidic drugs in 0.5% PGA gel. 1H-nuclear magnetic resonance spectroscopic analysis was carried out to examine the difference in mechanism of bitterness suppression between basic drugs and acidic drugs mixed with PGA gel. The signals of the proton nearest to the nitrogen atom of basic drugs shifted clearly upfield, suggesting an interaction between the amino group of basic drugs and the carboxyl group of PGA gel. In conclusion, PGA gel is expected to be a useful excipient in formulations contained various drugs, especially basic drugs;it also has advantage for not only increasing ease of swallowing but also masking the bitterness of drugs even though a small amount of a single drug dose might be preferred. 展开更多
关键词 poly-γ-Glutamic acid HYDROGEL BITTERNESS TASTE Sensor
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Features of Polymethacrylic Acid and Poly-2-Methyl-5-Vinylpyridine Hydrogels Remote Interaction in an Aqueous Medium 被引量:1
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作者 Alimbekova Bagyla Talgatovna Korganbayeva Zhanar Kozhamberdikyzy Himersen Huangul Kondaurov Ruslan Gennadievich Jumadilov Talkybek Kozhataevich 《Journal of Chemistry and Chemical Engineering》 2014年第3期265-269,共5页
The remote interaction of polymethacrylic acid hydrogel with a poly-2-methyl-5-vinylpyridine hydrogel was studied. The aim of work was to study the dependence of the swelling coefficient, the conductivity and the pH o... The remote interaction of polymethacrylic acid hydrogel with a poly-2-methyl-5-vinylpyridine hydrogel was studied. The aim of work was to study the dependence of the swelling coefficient, the conductivity and the pH of the water solutions of intergel system at different mass ratios from time were studied. The goal was achieved by using following methods: pH-metry, conductometry and gravimetry. 展开更多
关键词 Polyacrylic acid poly-2-methl-5-vinylpyridine intergel system.
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PREPARATION AND CELL COMPATIBILITY OF FUNCTIONALIZED BIODEGRADABLE POLY(DL-LACTIDE-co-RS-β-MALIC ACID)
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作者 何斌 顾忠伟 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第2期177-186,共10页
In order to create a functionalized biodegradable polymer for vascular tissue engineering application,poly(DL- lactide-co-RS-β-malic acid)(PDLLMAc)was synthesized.PDLLMAc was obtained after hydrogenolysis of poly(DL-... In order to create a functionalized biodegradable polymer for vascular tissue engineering application,poly(DL- lactide-co-RS-β-malic acid)(PDLLMAc)was synthesized.PDLLMAc was obtained after hydrogenolysis of poly(DL- lactide-co-RS-β-benzyl malolactonate)(PDLLMA),which was from the ring-opening polymerization of DL-lactide(DLLA) and RS-β-benzyl malolactonate(MA)using stannous octoate as catalyst.The copolymers were characterized by ~1H-NMR, FTIR,GPC and DSC.The tensile strength and water uptake of the copoly... 展开更多
关键词 BIODEGRADABLE Functionalization Poly(DL-lactide-co-RS-β-malic acid) Tissue engineering.
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An Anionic Polymer Incorporating Low Amounts of Hydrophobic Residues Is a Multifunctional Surfactant. Part 2: Emulsification, Moisture Absorption, and Moisture Retention of Alkyl Esterified Poly-γ-Glutamic Acid
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作者 Makoto Urai Tomoko Aizawa +1 位作者 Mutsuyasu Nakajima Michio Sunairi 《Advances in Chemical Engineering and Science》 2015年第2期181-191,共11页
In the accompanying paper (Part 1), we showed that the fatty acid moiety and the acidity of the polysaccharide-backbone of a fatty acid-containing polysaccharide might be involved in its emul-sification, moisture abso... In the accompanying paper (Part 1), we showed that the fatty acid moiety and the acidity of the polysaccharide-backbone of a fatty acid-containing polysaccharide might be involved in its emul-sification, moisture absorption, and moisture retention abilities. In this study, we synthesized alkyl esterified poly-γ-glutamic acid (PGA) with various chain lengths and degrees of substitution of the alkyl moieties to examine how hydrophobic groups incorporated in the anionic polymer contribute to enhanced emulsification, moisture absorption, and moisture retention. With a low degree of alkylation of PGA, these abilities were drastically improved. To improve the moisture absorption of PGA, alkylation with a short chain length is effective in forming interspaces between PGA chains to trap water molecules. Hydrophobic-hydrophilic balance may also be important to improve the emulsification and moisture retention abilities of PGA alkylates. To the best of our knowledge, this is the first report of the relationship between the structure and the multifunctional abilities of an anionic polymer incorporated with a small amount of hydrophobic residue. PGA alkylates, as well as fatty acid-containing polysaccharides, have potential use as multifunctional surfactants throughout various industries. 展开更多
关键词 poly-γ-Glutamic acid (PGA) ALKYL ESTER EMULSIFICATION MOISTURE Absorption MOISTURE Retention
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Adsorption of La^(3+) and Ce^(3+) by poly-γ-glutamic acid crosslinked with polyvinyl alcohol 被引量:2
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作者 高玉千 张世敏 +4 位作者 赵凯亚 王志伟 徐淑霞 梁振普 吴坤 《Journal of Rare Earths》 SCIE EI CAS CSCD 2015年第8期884-891,共8页
With the exploitation of rare earth ore, more and more rare earth elements came into groundwater, caused waste of resources and toxicity to the organisms. This study aimed to find an efficient adsorption material to m... With the exploitation of rare earth ore, more and more rare earth elements came into groundwater, caused waste of resources and toxicity to the organisms. This study aimed to find an efficient adsorption material to mitigate the above issue. Through doping polyvinyl alcohol with poly-γ-glutamic acid, an immobilised PSP gel particle was produced and had the adsorption rate of La3+ up to 97.10%. The factors including initial concentration of La3+ or Ce3+, adsorbent dosage, pH and temperature of the solution, which potentially affected the adsorption rate and were studied in batch mode. It was found that the optimum adsorption conditions were composed of 50 mg/L La3 VCe3+ of initial concentration, 600 mg/L (dry mass) biomass for adsorption, pH 6, temperature 30 ℃, 150 r/min rotational speed, and 1 h adsorption time. The selective adsorption of 15 different rare earth ions in mixed aqueous solu- tions were investigated. However, no significant selective differences were observed. Scanning electron microscopy showed that the morphological characteristic of the novel gel was its porous structure, while polyvinyl alcohol gel had a compact structure. Fourier transform infrared spectroscopy suggested that carboxyl groups in the poly-γ-glutamic acid might played a key role in the adsorption process. The adsorption mechanism forecasted to be cation exchange between -COOH and R3+. The adsorption kinetic and thermodynamic process for La3+ and Ce3+ was consistent with the pseudo-second-order equation and Langmuir adsorption isotherm model. It demonstrated that PSP gels particles were useful for removing REEs from wastewater. 展开更多
关键词 ADSORPTION rare earth ion poly-γ-glutamic acid polyvinyl alcohol
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Enhanced production of poly-γ-glutamic acid via optimizing the expression cassette of Vitreoscilla hemoglobin in Bacillus licheniformis 被引量:2
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作者 Qing Zhang Yaozhong Chen +5 位作者 Lin Gao Jian’gang Chen Xin Ma Dongbo Cai Dong Wang Shouwen Chen 《Synthetic and Systems Biotechnology》 SCIE 2022年第1期567-573,共7页
Poly-γ-glutamic acid(γ-PGA)is a natural polymer with various applications,and its high-viscosity hinders ox-ygen transmission and improvement of synthesis level.Vitreoscilla hemoglobin(VHB)has been introduced into v... Poly-γ-glutamic acid(γ-PGA)is a natural polymer with various applications,and its high-viscosity hinders ox-ygen transmission and improvement of synthesis level.Vitreoscilla hemoglobin(VHB)has been introduced into various hosts as oxygen carrier,however,its expression strength and contact efficiency with oxygen hindered efficient oxygen transfer and metabolite synthesis.Here,we want to optimize the expression cassette of VHB for γ-PGA production.Firstly,our results implied that γ-PGA yields were enhanced when introducing twin-arginine translocation(Tat)signal peptides(SP_(YwbN),SP_(PhoD) and SP_(TorA))into VHB expression cassette,and the best per-formance was attained by SP YwbN from Bacillus subtilis,theγ-PGA yield of which was 18.53% higher than that of control strain,and intracellular ATP content and oxygen transfer coefficient(K_(L)a)were increased by 29.71% and 73.12%,respectively,indicating that VHB mediated by SP YwbN benefited oxygen transfer and ATP generation forγ-PGA synthesis.Furthermore,four promoters were screened,and P vgb was proven as the more suitable promoter for VHB expression andγ-PGA synthesis,andγ-PGA yield of attaining strain WX/pPvgb-YwbN-Vgb was further increased to 40.59 g/L by 10.18%.Finally,WX/pPvgb-YwbN-Vgb was cultivated in 3 L fermentor for fed-batch fermentation,and 46.39 g/Lγ-PGA was attained by glucose feeding,increased by 49.26%compared with the initial yield(31.01 g/L).Taken together,this study has attained an efficient VHB expression cassette for oxygen transfer andγ-PGA synthesis,which could also be applied in the production of other metabolites. 展开更多
关键词 Vitreoscilla hemoglobin Expression element Twin-arginine translocation poly-γ-glutamic acid Bacillus licheniformis
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PREPARATION AND NONLINEAR OPTICAL PROPERTIES OF LB FILM OF POLY-11-METH-ACRYLAMINOUNDECANONIC ACID
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作者 陶凤岗 许临晓 +4 位作者 陈刚 杨心亮 王恭明 章志鸣 王文澄 《Chinese Science Bulletin》 SCIE EI CAS 1989年第14期1186-1189,共4页
In recent years, as a kind of organic molecular monolayers in orderly arrangements, Langmuir-Blodgett (LB) films have received increasing attention on account of their offering broader scope for applications in many f... In recent years, as a kind of organic molecular monolayers in orderly arrangements, Langmuir-Blodgett (LB) films have received increasing attention on account of their offering broader scope for applications in many fields including molecular elec- 展开更多
关键词 LB FILM poly-11-methacrylaminoundecanonic acid NONLINEAR optical properties
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Cloning and characterization of a new endo-type polyG-specific alginate lyase from bacteria Vibrio sp. QD-5
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作者 Yaxi Chao Shuyan Wang +2 位作者 Suqi Wu Jiaqiang Wei Hao Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第6期65-74,共10页
Seven bacterial clones with alginate-utilizing activity were isolated from rotten kelp. By activity test, the Vibrio sp. QD-5 with the potential alginate-degrading capability was chosen to carry out the draft genome s... Seven bacterial clones with alginate-utilizing activity were isolated from rotten kelp. By activity test, the Vibrio sp. QD-5 with the potential alginate-degrading capability was chosen to carry out the draft genome sequencing, and the result showed that the Vibrio sp. QD-5 containing an alginate lyase gene cluster. One of these genes, aly-IV, was cloned and characterized for the first time. After overexpression, Aly-IV, with a molecular mass of about 62 kDa and a theoretical isoelectric point (pI) of 5.12, was purified to a specific activity of 1 256.78 U/mg and showed highest activity at 35°C in the Tris-HCl buffer at pH of 8.9. Moreover, the enzyme activity was enhanced by the metal ions of Na+, K+ and Mg2+ under certain concentration. Aly-IV degraded favorably polyG blocks in an endo-type, yielding monomer and dimer as the main products. Due to its high substrate specificity, Aly-IV could be used as a potential tool for production of polyG oligosaccharides with low degree of polymerization (DP) and for determining the fine structure of alginate. 展开更多
关键词 ALGINATE LYASE VIBRIO sp. ALGINATE poly-α-L-guluronic acid LYASE OLIGOSACCHARIDES
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Genomic and metabolomic analysis of Bacillus licheniformis with enhanced poly-γ-glutamic acid production through atmospheric and room temperature plasma mutagenesis
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作者 Xiaoyu Wei Lijie Yang +6 位作者 Haiyan Wang Zhen Chen Yiyuan Xu Yue Weng Mingfeng Cao Qingbiao Li Ning He 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2022年第12期1751-1760,共10页
Poly-γ-glutamic acid is an extracellular polymeric substance with various applications owing to its valuable properties of biodegradability,flocculating activity,water solubility,and nontoxicity.However,the ability o... Poly-γ-glutamic acid is an extracellular polymeric substance with various applications owing to its valuable properties of biodegradability,flocculating activity,water solubility,and nontoxicity.However,the ability of natural strains to produce poly-γ-glutamic acid is low.Atmospheric and room temperature plasma was applied in this study to conduct mutation breeding of Bacillus licheniformis CGMCC 2876,and a mutant strain M32 with an 11%increase in poly-γ-glutamic acid was obtained.Genome resequencing analysis identified 7 nonsynonymous mutations of ppsC encoding lipopeptide synthetase associated with poly-γ-glutamic acid metabolic pathways.From molecular docking,more binding sites and higher binding energy were speculated between the mutated plipastatin synthase subunit C and glutamate,which might contribute to the higher poly-γ-glutamic acid production.Moreover,the metabolic mechanism analysis revealed that the upregulated amino acids of M32 provided substrates for glutamate and promoted the conversion between L-and D-glutamate acids.In addition,the glycolytic pathway is enhanced,leading to a better capacity for using glucose.The maximum poly-γ-glutamic acid yield of 14.08 g·L^(–1)was finally reached with 30 g·L^(–1)glutamate. 展开更多
关键词 ARTP mutagenesis Bacillus licheniformis poly-γ-glutamic acid metabolomics
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Effects of PSMA and experimental conditions on the morphologies of BaCO_3 whiskers
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作者 CHENG Bei YU Xiaoxiao YU Jiaguo ZHAO Xiujian 《Rare Metals》 SCIE EI CAS CSCD 2006年第4期382-388,共7页
BaCO3 whiskers exhibiting different morphologies were fabricated by a simple precipitation reaction of barium ch/oride with sodium carbonate in the absence and presence of poly-(styrene-alt-maleic acid) (PSMA) as ... BaCO3 whiskers exhibiting different morphologies were fabricated by a simple precipitation reaction of barium ch/oride with sodium carbonate in the absence and presence of poly-(styrene-alt-maleic acid) (PSMA) as a crystal growth modifier at room temperature. The as-prepared products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The influences of experimental parameters on the size and morphology of BaCO3 whiskers were investigated and discussed. It was found that the as-prepared BaCO3 whiskers are single crystals with diameter ranging from 100 to 300 run, and grow along the crystallographic a-axis or [100] direction. BaCO3 whiskers with different morphologies, such as branching and dendritic structure, can be obtained depending on the experimental conditions. With increasing PSMA concentration, the diameter of BaCO3 whiskers decreases. 展开更多
关键词 BaCO3 whiskers morphological control poly-(styrene-alt-maleic acid) single crystal
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Synthesis of the C5-C10 Segment of Taurospongin A
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作者 Zheng, GR Lu, W Cai, JC 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第8期663-664,共2页
Stereoselective synthesis of C5-C10 segment 3 of taurospongin A (1) has been developed successfully from L-(-)-malic acid.
关键词 stereoselective synthesis taurospongin A L-(-)-malic acid
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Efficient production of poly-γ-glutamic acid by Bacillus velezensis via solid-state fermentation and its application
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作者 Hong Liu Qiaojuan Yan +2 位作者 Yuchuan Wang Yanxiao Li Zhengqiang Jiang 《Food Bioscience》 SCIE 2022年第2期631-638,共8页
A novel glutamate-dependent poly-γ-glutamic acid(γ-PGA)-producing strain Bacillus velezensis CAU263 isolated from Chinese traditional Douchi was evaluated.An efficient method ofγ-PGA production was performed by thi... A novel glutamate-dependent poly-γ-glutamic acid(γ-PGA)-producing strain Bacillus velezensis CAU263 isolated from Chinese traditional Douchi was evaluated.An efficient method ofγ-PGA production was performed by this strain via solid-state fermentation(SSF)using guar meal.The maximal yield ofγ-PGA reached 158.5 g/kg dry weight(DW)in 250 mL flasks and 155.1 g/kg DW in shallow tray,respectively.The molecular weight ofγ-PGA was 3.8×106 Da,the ratio of L/D-glutamic acid was 26.1%and 73.9%.Additionally,γ-PGA significantly improved the operating characteristics of wheat dough,the specific volume of bread was increased by 15.8%and the bread hardness was reduced by 44.2%owing to the addition of 0.3 g/kgγ-PGA.Thus,γ-PGA could be produced by Bacillus velezensis CAU263 at high level using guar meal and might have potential application prospect in food industry. 展开更多
关键词 Bacillus velezensis poly-γ-glutamic acid Guar meal Solid-state fermentation Bread quality
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Synthesis of the C_(11-16)+C_(27) Segment of Epothilone A
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作者 Zhi Yu LIU Rui Fang WANG Yue Hai SHEN (Shanghai Institute of Organic Chemistry Chinese Academy of Sciences,354 Fenglin Lu. Shanghai 200032) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第1期35-38,共4页
A chiral synthesis of the C11-16+C27 segment of epomilone A is described using inexpensive L-(-)-malic acid as staring materinal and using Sharpless asymmetric epoxidahon for introduction of the desired 12, 13 epoxide.
关键词 Epothilone A L-(-)-malic acid asymmetric epoxidation
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A New Chiral Synthesis of Naturally Occurring (-)-(S)-4-Hydroxy-2-pyrrolidinone
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作者 Pei Qiang HUANG Xiao ZHENG +2 位作者 Shi Li WANG Jian Liang YE Li Ren JIN(Department of Chemistry, Xiamen University, Xiamen, Fujian 361005) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第9期735-736,共2页
A new and convenient chiral synthesis of naturally occurring (-)-(S)-4-hydroxy-2-pyrrolidinone from (S)-malic acid was reported.
关键词 (S)-malic acid (-)-(S)-4-hydroxy-2-pyrrolidinone ionic hydrogenation
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Effect of PLA Knitted Structure on the Mechanical Properties of Composite Vascular Scaffold
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作者 LI Chao-jing LI Xuan +4 位作者 WANG Fu-jun GE Peng MAO Ying WANG Lu MARTIN W. King 《Journal of Donghua University(English Edition)》 EI CAS 2014年第5期659-663,共5页
A new entire biodegradable scaffold has been developed which does not require precellularization before transplantation.This new kind of vascular scaffold prototype made from porous poly-ε-caprolactone( PCL) membrane... A new entire biodegradable scaffold has been developed which does not require precellularization before transplantation.This new kind of vascular scaffold prototype made from porous poly-ε-caprolactone( PCL) membrane to provide three-dimensional environment for cell growth, and embedded with weft-knitted polylactic acid( PLA) fabric to support mechanics.The aim of this paper is to study the variation tendency of mechanical properties with the fabric spacing changing.The basic geometrical parameters were measured to characterize properties of the samples.The tensile and compressive elastic recovery of the samples were tested by the universal mechanical tester and radial compression apparatus,respectively.Both tensile and compressive properties enhanced when reducing the fabric spacing of the composite vascular scaffold. 展开更多
关键词 vascular scaffold polylactic acid(PLA) poly-εcaprolactone(PCL) knitted fabric composite structure mechanical properties
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Studies on HUFA Biosynthesis in a Marine Teleost Siganus Canaliculatus
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作者 Yuan-You Li Liang Zhang Su-Qi Wang Shu-De Xu Chang-bo Hu Yi-Jun Zheng 《Feed & Livestock》 2010年第2期7-7,共1页
Marine fish are incapable or have a deft- cient capacity to synthesize highly unsaturated fatty acids (HUFA) from C18 precursors, and thus fish meal and fish oil (FO) are needed in their formulated diets.
关键词 Marine fish Biosynthesis of poly- unsat-urated fatty acids Nutritional regulation Salinityregulation
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A Flexible Approach to the γ-Amino-β-hydroxy Acid Moiety of Hapalosin
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作者 黄培强 吴天俊 叶剑良 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2003年第7期723-726,共4页
A flexible approach to ethyl (3R,4S)-N-Boc-4-amino-3-hy-droxy-5-phenyIpentanoate (N-Boc-AHPPA-OEt), the γ-amino-β-hydroxy add moiety of hapalosin is described. The synthetic method features a ring-opening ethanolysi... A flexible approach to ethyl (3R,4S)-N-Boc-4-amino-3-hy-droxy-5-phenyIpentanoate (N-Boc-AHPPA-OEt), the γ-amino-β-hydroxy add moiety of hapalosin is described. The synthetic method features a ring-opening ethanolysis of an activated N-Boc-lactam, which is obtained via a diastereoselective reductive-alkylation of (R)-malimide derivative. The flexibility of the method resides hi the introduction of the alkyl side chain by Grignard reagent addition. 展开更多
关键词 (R)-malic acid hapalosin anti-AHPPA asymmet-ric synthesis reductive alkylation
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