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Synthesis and antitumor activity of novel 10-amino acids ester homocamptothecin analogues 被引量:3
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作者 Liang You Wan Nian Zhang Zhen Yuan Miao Wei Guo Xiao Ying Che Wen Ya Wang Chun Quan Sheng Jiang Zhong Yao Ting Zhou 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第7期811-813,共3页
Nine racemic homocamptothecin derivatives were synthesized and in vitro antitumor activities were evaluated by standard MTT method. The results showed that some of the compound had higher antitumor activity than irite... Nine racemic homocamptothecin derivatives were synthesized and in vitro antitumor activities were evaluated by standard MTT method. The results showed that some of the compound had higher antitumor activity than iritecan. 展开更多
关键词 Homocamptothecin amino acids ester Antitumor activity SYNTHESIS
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Effects of Processing Variables on the Morphology and Diameter of Electrospun Poly(amino acid ester)phosphazene Nanofibers 被引量:2
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作者 林益军 DENG Qinghua JIN Riguang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第2期207-211,共5页
Poly[(alanino ethyl ester)0.67 (glycino ethyl ester)0.33 phosphazene] (PAGP) was synthesized, and morphology and diameter of the electrospun PAGP nanofibers were systematically evaluated by using a cool field em... Poly[(alanino ethyl ester)0.67 (glycino ethyl ester)0.33 phosphazene] (PAGP) was synthesized, and morphology and diameter of the electrospun PAGP nanofibers were systematically evaluated by using a cool field emission scanning electron microscope (SEM) with changing the important processing variables such as applied voltage, polymeric concentration, and ambient temperature. The average diameter of PAGP nanofibers was inversely proportional to the applied voltage, but increased with the increase of solution concentration. Lower environmental temperature was unfavorable due to the nanofibers conglutination. 展开更多
关键词 ELECTROSPINNING MORPHOLOGY poly(amino acid ester)phosphazene NANOFIBERS
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Pyrolysis-GC/MS of Menthyl Esters of N-Benzoxycarbonyl Amino Acid 被引量:1
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作者 MAO Mao GU Cheng-zhi +2 位作者 YIN Hao SONG Qin-hua LI Qlan-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第2期198-203,共6页
With the aid of a Pyrolysis-GC/TOF MS technique, the pyrolysis behaviour of two menthyl esters of N-benzoxycarbonyl amino acid was investigated. A clear pattern emerges involving the cleavage of the bond linking the m... With the aid of a Pyrolysis-GC/TOF MS technique, the pyrolysis behaviour of two menthyl esters of N-benzoxycarbonyl amino acid was investigated. A clear pattern emerges involving the cleavage of the bond linking the menthyl ring to the carboxy group, followed by further degradation of the fragments. The major pyroproducts were p-menth-l-ene pyrolysed at a higher temperature or p-menth-2-ene pyrolysed at a lower temperature, and various derivatives of cyclohexene pyrolyzed from the menthyl ring. In addition, some of the products were also iden- tified as derivatives of benzene from the pyrolysis of benzyloxyl moiety. 展开更多
关键词 Menthyl esters of N-benzoxycarbonyl amino acid Py-GC/MS PYROLYSIS
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A SYNTHESIS OF TETRAMETHYL ETHER OFROSMARINIC ACID BENZYL ESTER 被引量:1
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作者 Yan ZHUANG Zong Ru GUO +1 位作者 Guang Zhong YANG Xiao Tian LIANG(Institute of Materia Medial Chinese Academy of Medical SciencesPeking Union Medical College, Xian Nong Tan Street,Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第6期507-508,共2页
A rosmarinic acid derivative, tetramethyl ether of rosmarinic acid benzyl ester, was synthesized. This is the first report of building this structural skeleton.
关键词 acid A SYNTHESIS OF TETRAMETHYL ETHER OFROSMARINIC acid benzyl ester
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The Synthesis of Hexamethyl Ether of Salvianolic Acid A Benzyl Ester 被引量:2
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作者 Yan ZHUANG Zong Ru GUO +1 位作者 Guang Zhong YANG Xiao Tian LIANG(Institute of Materia Medica.Chinese Academy of Medical Sciences Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第10期888-891,共4页
A salvianolic acid A derivative, hexamethyl ether of salvianolic acid A benzyl ester, was synthesized in fourteen steps. The overall yield was 3.4 parts per thousand. The compound was identified by (1)HNMR and MS. Thi... A salvianolic acid A derivative, hexamethyl ether of salvianolic acid A benzyl ester, was synthesized in fourteen steps. The overall yield was 3.4 parts per thousand. The compound was identified by (1)HNMR and MS. This is the first report of building this structural skeleton. 展开更多
关键词 The Synthesis of Hexamethyl Ether of Salvianolic acid A benzyl ester
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NMR Studies of a New Binding Mode of the Amino Acid Esters by Porphyrinatozinc(Ⅱ)
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作者 PENG Xiao-bin HUANG Jin-wang +1 位作者 LI Tao JI Liang-nian 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2001年第1期1-5,共5页
The binding mode of the amino acid ethyl esters(guest) by 5 (2 carboxylphenyl) 10,15,20 triphenylporphyrinatozinc(Ⅱ)(host 1) was studied by means of 1H NMR spectra. The binding mode is the hydrogen bonding between th... The binding mode of the amino acid ethyl esters(guest) by 5 (2 carboxylphenyl) 10,15,20 triphenylporphyrinatozinc(Ⅱ)(host 1) was studied by means of 1H NMR spectra. The binding mode is the hydrogen bonding between the amino group of the guest and the carboxyl group of host 1 plus the coordination between the zinc atom of porphyrinatozinc(Ⅱ) and the carbonyl group of the guest. This is a novel binding mode of the metalloporphyrin to amino acid derivatives. 展开更多
关键词 H NMR Porphyrinatozinc(Ⅱ) amino acid ester New binding mode
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Electrospray Ionization Mass Spectra of Amino Acid Methyl Ester 5′-Phosphoramidates of 2′,3′-Isopropylideneuridine
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作者 CHEN Wei-zhu GAO Yu-xing +2 位作者 BAI Yong-gang HAN Da-xiong ZHAO Yu-fen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第6期732-737,共6页
Amino acid methyl ester phosphates were synthesized and determined by using positive-ion mode dectrospmy ionization mass spectrometry(ESIMS) in combination with multistage tandem mass spectrometry. The fragmentation... Amino acid methyl ester phosphates were synthesized and determined by using positive-ion mode dectrospmy ionization mass spectrometry(ESIMS) in combination with multistage tandem mass spectrometry. The fragmentation pathways were investigated, and it was observed that most fragment ions contained the phosphoryl group. It was interesting to observe that the fragmentation pathways of the protonated molecule show some differences when compared with those of the sodium ion adduct. The methoxy group of amino acid methyl ester can migrate from the carbonyl group to the phosphoryl group in the sodium ion adduct. 展开更多
关键词 ESIMS Fragmentation pathway Methoxy group rearrangement Pentacoordinated phosphorus intermediate amino acid methyl ester 5'-phosphoramidate of nucleoside
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Novel Phosphonoacetic Acid Derivatives.Synthesis of N-(Ethoxycarbonylmethylphosphonyl)-α-Amino Esters and-α-Amino Phosphonic Acid Esters and Their Bioactivities
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作者 Hui Ying LI Kang Tai REN Ru Yu CHEN(Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,0-0,共4页
A series of novel phosphonoacetic acid derivatives, N-(ethoxycarbonylmethy-ethoxyphosphonyl)-α-amino acid esters and α-amino phosphonates, were synthesized via the reaction of the corresponding phosphonyl chloride ... A series of novel phosphonoacetic acid derivatives, N-(ethoxycarbonylmethy-ethoxyphosphonyl)-α-amino acid esters and α-amino phosphonates, were synthesized via the reaction of the corresponding phosphonyl chloride with amino acid ester hydrochlorides or amino phosphonates in the presence of a base. The preliminary bioassay shows that some compounds show significant anti-viral activity against tobacco mosaic virus (TMV) 展开更多
关键词 Novel Phosphonoacetic acid Derivatives.Synthesis of N cm PN amino Phosphonic acid esters and Their Bioactivities Ethoxycarbonylmethylphosphonyl amino esters and
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Microwave-Assisted Facile and Rapid Esterification of Amino Acids I: Esterification of L-Leucine from Batch to Flow Processes and Scale-Up
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作者 Ritsuko Nagahata Takashi Nakamura +1 位作者 Yukie Mori Kazuhiko Takeuchi 《Natural Science》 2017年第4期110-122,共13页
We herein report our studies into the effects of microwave irradiation on the solvent-free esterification of L-leucine with alcohols. In the absence of solvent, microwave irradiation accelerated the reaction compared ... We herein report our studies into the effects of microwave irradiation on the solvent-free esterification of L-leucine with alcohols. In the absence of solvent, microwave irradiation accelerated the reaction compared to conventional oil bath heating. Measurement of the dielectric properties under the reaction conditions revealed that the high dielectric loss factor of the reaction mixture containing L-leucine, n-butanol, and a p-toluene sulfonic acid catalyst could be attributed to the acceleration of the reaction. The depth of microwave penetration into the reaction mixture as derived from the in-situ measurement of the dielectric properties was ~13 mm, which suggested that a thinner reaction vessel was favorable for the esterification of L-leucine. In addition to the batch reaction using a desktop microwave reactor, two types of flow reaction were also performed using a desktop tubular reactor and a semi-bench-scale tubular reactor. These flow reactions also exhibited high performances, thus allowing the scale-up of this reaction system for industrial use. 展开更多
关键词 MICROWAVE-ASSISTED esterIFICATION Microwave Flow Reactor Dielectric Properties amino acid ester L-LEUCINE
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A NEW ONE-STEP REDUCTIVE N-ALKYLATION OF AMINO ACIDS AND THEIR ESTERS
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作者 De Ling Zhou Ye Di Guan Sheng Jin Department of Chemistry,Peking University,Beijing,100871 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第3期209-210,共2页
The reductive alkylation of amine with carbonyl compounds using sodium hydrogen telluride has been investigated in recent years. Application of this method to the synthesis of N-alkyl derivatives of biologically impor... The reductive alkylation of amine with carbonyl compounds using sodium hydrogen telluride has been investigated in recent years. Application of this method to the synthesis of N-alkyl derivatives of biologically important amino acids and their esters is described. 展开更多
关键词 Ph HC STEP A NEW ONE-STEP REDUCTIVE N-ALKYLATION OF amino acidS AND THEIR esterS
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STUDIES ON THE SYNTHESIS AND ANTITUMOR ACTIVITY OF AMINO ACID ESTER DERIVATIVES OF BENZISOSELENAZOLONE
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作者 Xiu Fang LIU Ying Xin XIAO +2 位作者 Guo Jun ZHANG Han Sheng XU Fan Bo ZHENG 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第3期161-162,共2页
This paper reports a simple method for the synthesis of amino acid ester derivatives of benzisoselenazolone.Their anticancer activity is also given.
关键词 DE acid STUDIES ON THE SYNTHESIS AND ANTITUMOR ACTIVITY OF amino acid ester DERIVATIVES OF BENZISOSELENAZOLONE
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Synthesis of Macrocycles Containing Amino Acid Ester and Aryl-heterocyclic Units
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作者 Yan Tao CHEN Wen Ting HUA Qi Yi XING(Department of Chemistry Peking University Beijing 100871) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,0-0,共4页
Four kinds of new macrocycles containing amino acids and nyl-heterocyclic units were synthesized by the condensation of di-esters containing Ts-amino acids units with di-halogenated compounds at room temperature. The ... Four kinds of new macrocycles containing amino acids and nyl-heterocyclic units were synthesized by the condensation of di-esters containing Ts-amino acids units with di-halogenated compounds at room temperature. The macrocycles were characterized by elemental analysis, IR,MS(FAB) and 1H NMR 展开更多
关键词 FAB Synthesis of Macrocycles Containing amino acid ester and Aryl-heterocyclic Units
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Diastereoselective α-Alkylation of β-Amino Esters: Preparation of Novel α-Substituted β-Amino Esters from α-Amino Acids
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作者 ZhiHuaMA CongLIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第8期721-724,共4页
Enantiomerically pure a-substituted bamino esters were prepared from natural L-a-amino acids through Arndt-Eistert homologation and diastereoselective aalkylation.
关键词 DIASTEREOSELECTIVITY ALKYLATION b-amino esters. Diastereoselective aAlkylation of bamino esters: Preparation of Novel aSubstituted bamino esters from aamino acids Zhi Hua MA Cong LIU Yong Hua ZHAO Wei LI Jian Bo WANG* Key Laboratory of
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Catalytic Hydrolysis of Lipophilic Amino Acid Esters by Metallomicelles as Carboxypeptidase A Models
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作者 Xiao Qi YU Jing Song YOU +2 位作者 Qing Xiang XIANG Qian Shun YAN Ru Gang XIE (Department of Chemistry, Sichuan University, Chengdu 610064) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第8期731-732,共2页
Lipophilic complexes of macrocyclic 12-membered dioxotetraamine ligand bearing bis-hydroxy groups as functional pendants are effective catalysts for the hydrolysis of amino acid esters in micellar media, and the rate ... Lipophilic complexes of macrocyclic 12-membered dioxotetraamine ligand bearing bis-hydroxy groups as functional pendants are effective catalysts for the hydrolysis of amino acid esters in micellar media, and the rate enhancement of more than 10-fold were observed. 展开更多
关键词 metallomicelles lipophilic complexes amino acid esters HYDROLYSIS
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Preparation and Surfactant Properties of Amino Acid-based Surfactants 被引量:4
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作者 Qian CHEN Steven F. CHEN Zu Yi LI(1 Shanghai Institute of Organic Chemistry. Chinese Academy of Sciences. 354 Fenglin Lu.Shanghai 2000322 Depaftment of Botany. The University of Hong Kong) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第9期789-792,共4页
1-O-aminoacyl-3-O-alkyl acyl glycerols were synthesized by lipases in good yields and their surfactant properties were explored.
关键词 amino acids LIPASE fatty acids glycerol esters
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The Synthesis of Cyclic Amino Acids 被引量:2
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作者 Shrong Shi LIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第9期883-884,共2页
Several cyclic amino acids (1-4) were synthesized from glycine. Isocyanate ester was prepared as the key intermediate and reacted with dibromoalkanes to afford the target compounds.
关键词 Cyclic amino acid isocyanate ester dibromoalkane ion exchange resin.
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The Synthesis of Some Novel N-[α-(Isoflavone-7-O-) Acetyl]Amino Acid Derivatives 被引量:1
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作者 Peng LIU Jun Biao CHANG +2 位作者 Rong Feng CHEN Qiang WANG Jing Xi XIE (Henan Institute of Chemistry, Henan Academy of Science, Zhengzhou 450002 Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第5期391-394,共4页
A series of novel N-[α-(isoflavone-7-O-)acetyl] amino acid methyl esters were prepared from the efficient and regioselective alkylation of isoflavones with chloroacetyl amino acid derivatives under mild condition.
关键词 Isoflavone analogues N-[α-(isoflavone-7-O-)acetyl] amino acid methyl ester synthesis.
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Exploring Ester Prodrugs: A Comprehensive Review of Approaches, Applications, and Methods
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作者 Guangyang Zhou 《Pharmacology & Pharmacy》 2024年第8期269-284,共16页
The review provides an overview of the approaches, applications, and methods for ester prodrugs. Ester prodrugs are pharmacologically inactive compounds in their original form but become active drugs on biotransformat... The review provides an overview of the approaches, applications, and methods for ester prodrugs. Ester prodrugs are pharmacologically inactive compounds in their original form but become active drugs on biotransformation within the body, which offers advantages concerning the solubility, stability, and targeted delivery of the active drug. Several approaches of ester prodrugs have been reviewed in this review, including simple ester prodrugs, amino acid ester prodrugs, sugar ester prodrugs, lipid ester prodrugs, and polymeric ester prodrugs. This review incorporates in vitro and in vivo methods as well as the characterization of physical and chemical properties for ester prodrugs, cell culture systems, enzymatic assays, and animal models—all of these having a very important bearing on the evaluation of stability, bioavailability, and efficacy for ester prodrugs. While the benefits of using ester prodrugs are significant, there are also disadvantages like instability, poor or variable enzymatic hydrolysis, and toxicity from released promoieties or by-products. This review discusses solutions to the various limitations that include enhancing stability with ionizable promoieties and using physiologically-based pharmacokinetic modeling. The review also highlights the application of ester prodrugs in neurological disorders, such as Parkinson’s disease, and the ongoing efforts to address the critical limitations in treatment efficacy. Future prodrug strategies are poised to advance significantly by harnessing diverse transport mechanisms across the blood-brain barrier and integrating nanotechnology. 展开更多
关键词 ester Prodrugs Solubility BIOAVAILABILITY Stability ester Prodrug Approaches Simple ester Prodrugs amino acid ester Prodrugs Sugar ester Prodrugs Lipid ester Prodrugs Polymeric ester Prodrugs esterase-Responsive Nanoparticles Hydrolysis Cancer Treatment Cardiovascular Diseases Neurological Disorders
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Highly efficient synthesis of β-amino esters via Mannich-type reaction under solvent-free conditions using ZnCl_2 catalyst 被引量:8
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作者 Albert S.C.Chan 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期407-410,共4页
β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid de... β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid derivatives. 展开更多
关键词 β-amino esters Aspartic acid derivativates Mannich-type reaction SOLVENT-FREE Krapcho decarboxylation reaction Zinc chloride
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熊果酸及其氨基酸酯前体药物在大鼠体内的药动学研究 被引量:1
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作者 赵婷婷 付宇含 +3 位作者 秦紫宸 宁亚楠 郭夫江 李医明 《沈阳药科大学学报》 CAS CSCD 2024年第6期734-741,共8页
目的 建立测定大鼠血浆中熊果酸浓度的超高效液相色谱串联质谱(UPLC-MS/MS)分析方法,探讨熊果酸及其氨基酸酯前体药物在大鼠体内的药动学变化。方法 取雄性大鼠,经口给药70 mg·kg^(-1)(以熊果酸含量计)的熊果酸原料药,熊果酸-维生... 目的 建立测定大鼠血浆中熊果酸浓度的超高效液相色谱串联质谱(UPLC-MS/MS)分析方法,探讨熊果酸及其氨基酸酯前体药物在大鼠体内的药动学变化。方法 取雄性大鼠,经口给药70 mg·kg^(-1)(以熊果酸含量计)的熊果酸原料药,熊果酸-维生素E琥珀酸聚乙二醇酯混合液,熊果酸苯丙氨酸肌氨酸酯盐酸盐-维生素E琥珀酸聚乙二醇酯溶液。采用沉淀蛋白法处理血浆样品,以塞来昔布作为内标,色谱柱为Acquity UPLC~? BEH C18(50 mm×2.1 mm, 1.7μm)柱,流动相为体积分数0.025%氨水乙腈-10 mmol·L^(-1)乙酸铵-体积分数0.1%氨水溶液(体积比70∶30),流速0.4 mL·min^(-1),采用大气压化学电离源,负离子多反应监测模式扫描。结果 血浆中熊果酸在质量浓度100~10 000μg·L^(-1)内线性良好。与原料药比较,熊果酸-维生素E琥珀酸聚乙二醇酯混合液组和熊果酸苯丙氨酸肌氨酸酯盐酸盐-维生素E琥珀酸聚乙二醇酯溶液组的熊果酸生物利用度分别提高了8.43倍和19.52倍(P<0.05)。结论 经口给药后熊果酸在大鼠体内的生物利用度较低,前体药物熊果酸苯丙氨酸肌氨酸酯可提高熊果酸的经口给药生物利用度。分析方法符合生物样品的测定要求,适用于大鼠血浆中熊果酸质量浓度的测定。 展开更多
关键词 熊果酸 氨基酸酯前药 熊果酸苯丙氨酸肌氨酸酯盐酸盐 UPLC-MS/MS 药动学
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