加味五子衍宗方及其活性部位对脂多糖诱导神经炎症反应的抑制作用及机制研究

目的研究加味五子衍宗方及其活性部位对脂多糖诱导的BV-2小胶质细胞炎症反应的抑制作用及潜在机制。方法通过大孔树脂柱,将加味五子衍宗方乙醇总提取物洗脱分离得到水提组、20%醇提组、50%醇提组、70%醇提组和95%醇提组5个部位。针对无细胞毒性的部位研究了其对炎症因子一氧化氮和炎症蛋白诱导型一氧化氮合酶,环氧合酶-2表达的影响,明确了抗炎活性部位,同时进一步研究了活性部位对核转录因子的激活以及活性氧表达的调控作用。结果70%醇提组和95%醇提组对细胞具有毒性,其余各部位(水提组,20%醇提组,50%醇提组)均无细胞毒性且表现出一定的抗炎活性。其中50%醇提组抗炎活性最优,甚至高于复方组。结论加味五子衍宗方的抗炎活性部位可能主要富集于50%醇提部分,其抗炎活性可能是通过抑制NF-κB信号通路介导的炎症反应以及抗氧化应激实现的。

苯骈呋喃酮类化合物的质谱裂解特征研究

目的研究丁苯酞等5个苯骈呋喃酮类化合物的质谱裂解特征。方法对于手性拆分的丁苯酞及丙苯酞采用质谱分析,丁烯苯酞的两个顺反异构体采用液相-质谱联用技术进行分离分析,并对5个苯骈呋喃酮类化合物的多级质谱裂解规律进行了详细解析。结果通过得到离子碎片的组成结构,可以进一步推断得出5个复杂的差向异构体或顺反异构体化合物形成碎片离子的裂解途径。结论该法简便、快速、准确,有助于对此类结构化合物更多的研究。

岩白菜素及其衍生物抗炎活性的相关研究进展

岩白菜素是来源于虎耳草科岩白菜属的一种融合的4-O-甲基没食子酸的葡萄糖β-碳苷,它具有多种多样的生物活性。本文重点就岩白菜素的抗炎生物活性及其相关结构修饰进行了综述。

岩白菜素及其衍生物抗肿瘤活性的相关研究进展

岩白菜素是从多种科属植物的根茎、树皮或叶中提取的天然次生代谢产物,其药理活性多种多样,近年来针对其不同活性所做的结构修饰研究也有很多。本文重点对岩白菜素及其衍生物的抗肿瘤活性及相关结构修饰做具体介绍。

具有生物活性的多价糖肽的研究进展

糖蛋白复合物是许多疾病诊断与治疗中的重要生物标志分子。糖与蛋白之间的作用通常表现出高度特异性和弱的亲和力,化学家们通过合成多价簇状糖来解决糖亲和力太低的问题。本文对近年来代表性的多价糖肽合成工作及其生物应用做了简要概述。

Calf spleen extract alleviates cyclophosphamide-induced leucopenia in mice and inhibits the glycolysis of HL60 cells

Calf spleen extract(CSE) has been clinically used as an adjuvant agent in malignant tumor therapy.It can improve the physical status of patients.However,its mechanism of action remains relatively unclear.In this study,we investigated the effect of CSE on leucopenia in mice and on promyelocytic leukemia cells(HL60).CSE in 10 mL/kg(2.5 mg bioactive polypeptides and 190μg ribose/mL) significantly increased leukocyte numbers in leucopenia mice.The effect on neutrophil numbers,among all leukocytes,was the most evident.CSE stimulated the proliferation of bone marrow cells in vitro and decreased the GM-CSF level in serum.In addition,CSE significantly reduced the viability of HL60 cells,decreased the production of lactate and adenosine triphosphate(ATP) of these cells.CSE induced the apoptosis and S-phase arrest in HL60 cells.In conclusion,CSE can enhance leukocyte numbers,which may be attributed to its direct stimulatory effect on bone marrow cells.CSE is an inhibitor of promyelocytic leukemia cell viability,which may be attributed to the induction of the apoptosis,the arrest of cell cycle and the inhibition of the glycolysis of cells.

咖啡酸苯乙酯对抗脂多糖诱导的小胶质细胞炎症反应的作用及其机制的研究

目的探究咖啡酸苯乙酯对脂多糖诱导的小胶质细胞BV-2神经炎症反应的抑制作用及其潜在的作用机制。方法采用脂多糖(1μg·mL-1)诱导小胶质细胞BV-2活化,制作炎症反应模型,利用四甲基偶氮唑蓝法检测细胞存活率,并用酶联免疫法测定咖啡酸苯乙酯对炎症因子一氧化氮、白细胞介素-1β和白细胞介素-6合成释放的影响。然后用蛋白印迹法研究了咖啡酸苯乙酯对炎症相关蛋白(诱导型一氧化氮合酶、环氧化酶-2、IκB以及P-IκB)表达的作用。此外,进一步研究了咖啡酸苯乙酯对炎症转录因子NF-κB核转位的作用。结果咖啡酸苯乙酯与脂多糖(1μg·mL-1)同时作用于BV-2小胶质细胞,分别于温箱中孵育24、8 h收集上清液,检测一氧化氮、白细胞介素-1β、白细胞介素-6的释放量。结果显示,脂多糖(1μg·mL-1)可以造成细胞损伤,增加炎症因子释放,咖啡酸苯乙酯则可以降低脂多糖诱导的小胶质细胞对一氧化氮、白细胞介素-1β和白细胞介素-6的释放,并可抑制诱导型一氧化氮合酶、环氧化酶-2、P-IκB、P-NF-κB蛋白的表达,还可以抑制NF-κB的核转位。结论上述研究说明,咖啡酸苯乙酯(5,10,20μmol·L-1)可以通过抑制炎性因子的表达而减少对小胶质细胞的损伤,其抗炎活性可能是通过抑制NF-κB信号通路介导的炎症反应实现的。

Rapid characterization of 96 chemical constituents in Citri Reticulatae Folium(leaves of ‘Fuju') using HPLC-DAD-ESI-MS^n

In order to systematically investigate the chemical constituents of Citri Reticulatae Folium （leaves of ＇Fuju＇）, an analytical method that included high-performance liquid chromatography, diode array detection, electrospray ionization, and ion-trap time-of-flight mass spectrometry （HPLC-DAD-ESI-MSn） was used to separate and identify the individual chemical components of Citri Reticulatae Folium. As a result, 96 compounds were tentatively identified in this study： including 31 phenolic acids, 4 flavonoid aglycones, 6 flavonoid mono-O-glycosides, 10 flavonoid-O-diglycosides, 5 flavonoid mono-C-glycosides, 5 flavonoid di-C-glycosides, 6 flavonoid O,C-glycosides, 5 （3-hydroxy-3-methylglutaryl） glycosyl flavonoids, 1 flavan-3-ol, and 2 alkaloids. In addition, 21 polymethoxy flavonoids （PMFs） were identified in this paper. Among these compounds, 52 compounds, which were previously found in other Citrus plants, have been identified for the first time in Citri Reticulatae Folium. 15 compounds have not been previously found in the Citrus genus were identified. Moreover, 9 potentially new compounds have also been detected in this paper. This is the first report of the full characterization of chemical components of Citri Reticulatae Folium （leaves of＇Fuju＇） by HPLC-DAD-ESI-MSn.

Spectrophotometric studies on the interaction between chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid and lysozyme

The interactions of chlorogenic acid （CA）, neochlorogenic acid （NCA） and cryptochlorogenic acid （CCA） with lysozyme （LYSO） were investigated in physiological buffer by fluorescence spectroscopy. The mechanism study indicated that CA, NCA and CCA could strongly quench the intrinsic fluorescence of LYSO through static quenching procedures with one binding site. Thermodynamic data show that the major force in the binding processes of CA to LYSO was hydrophobic interactions; for NCA, it was the hydrogen bonds and van der Waals forces, as for the CCA system, the mainly force is electrostatic force.

Synthetic strategies for piperazine derivatives

As important constitutes in many drugs, piperazine comprised compounds are of great interest for drug design. In this paper, two piperazine-based compounds were synthesized for the first time, with different strategies exploited. For one compound, a highly reactive intermediate of isothiocyanate was constructed to get the desired piperazinecarbothioamide. The synthesis of the other compound was completed sequentially through Friedel-Crafts acylation, coupling reaction and Michael addition. Both synthetic routes have short steps and acceptable yields, and such strategies can be applied to the synthesis of similar oioerazine-containin~ comoounds.

Design, synthesis and biological evaluation of sulfonamide flavone derivatives as potential 20S proteasome inhibitors

A new series of sulfonamide flavone derivatives are designed as non-covalent inhibitors of proteasome assisted with computer-aided drug design （CADD）. The desired compounds were synthesized successfully and the biological evaluation was subsequently accomplished. The results showed negligible improvement from our lead compound （IC50 for β5 subunit was 14.0 μM）. Thus, these flavone derivatives might be improved as potential 20S proteasome inhibitors.

Structure-based design of hexahydropyrimidin-5-ols as novel non-peptidic β-secretase inhibitors

Based upon the crystal structure of a previously reported fragment hit that binds to Corresponding author. β-secretase, a novel series of non-peptidic small-molecule β-secretase inhibitors, namely hexahydropyrimidin-5-ols, along with two series of their analogues, were rationally designed through structural modification. The CADD study was performed and revealed good expectation. Inhibitory activities of the corresponding structural cores were tested, which provided further support for our design approach.

Design,synthesis and bioevaluation of isoflavone derivative as a novel CLR/RAMP1 antagonist

CGRP receptor（CLR） is a B class GPCR that functions only when combined with RAMPs. CLR/RAMP1 has been regarded as a promising target for migraine treatment, as its antagonists have been proved to be effective recently. In the present study we designed and synthesized small molecular antagonists against CLR/RAMP1, resulting in a novel type of structure with acceptable high potency. The molecules were designed via virtual screening. Afterwards, a series of modification were conducted on the hit compounds, resulting in compound 8 as the best scored compound in docking, which was further validated in vitro by cell-based functional assay.

Design,synthesis and biological evaluation of pyrrolidinone analogs as potential 20S proteasome inhibitors

A novel series of pyrrolidinone analogs that are designed as Michael addition acceptors to react irreversibly with the proteasome active site Thr1O~γhave been synthesized.Although biological evaluation results show that the compounds display poor inhibitory activity towards the proteasome active sites,pyrrolidinone analogs might still be modified to be potential 20S proteasome inhibitors.

Synthesis of acyclic analogs of Syringolin A as potential 20S proteasome inhibitors

A series of acyclic analogs of natural product Syringolin A （SylA） were designed and synthesized during our synthetic efforts for SylA. These acyclic analogs were prepared through a seven-step linear strategy, with total yields varying from 20%-34% for one type of analogs and 12%-18% for the other. These compounds bear a common structure of peptidyl vinyl amide, which reacts irreversibly with the proteasomal active site ThrlO^γ through Michael-type 1,4-addition. Therefore, these acyclic analogs may function the same way as SylA, as potential 20S proteasome inhibitors.

Design and synthesis of benzimidamides as potential BACE1 inhibitors

Computer aided fragment-based lead discovery has been successfully applied to the design of inhibitors of aspartyl protease enzyme β-secretase（BACE1）.A benzimidamide fragment,which binds to the two catalytic aspartic acid residues in the active site of the enzyme,was selected as the starting compound.A novel series of 3-phenethylbenzimidamide inhibitors were designed and synthesized.Although biological evaluation results showed that the compounds displayed poor inhibitory activity towards BACE1,3-phenethylbenzimidamide analogs might be modified as potential BACE1 inhibitors.

Synthesis of the arsenic-containing amino-acids, and their potential applications in peptide chemistry

Trivalent organoarsenic compounds have attracted a great deal of interest because of their potential antineoplastic activities. In this work, we synthesized a series of arsenic-containing amino acid analogues by introducing the structure of 1-arsino-2,6,7- trithiobicyclo[2.2.2]octane to the side chain of modified amino acid derivatives. The protected amino acid （6a） as a typical objective compound was applied in peptide synthesis via the classic procedures for the formation of peptide bond or removal of protecting groups. Our results showed that the application of compound 6a （or 5a） in the peptide chemistry was satisfactory.

Two alkaloids as α-amylase inhibitors: enzyme kinetics and molecular modeling investigations

In the present study, we studied the inhibitory effects of chelidonine and rutaecarpin on porcine pancreatic a-amylase （PPA） catalyzed hydrolysis using 2-chloro-4-nitrophenyl-4-O-β-D-galactopyranosylmaltoside （Gal-G2-α-CNP）. We, for the first time, provided kinetic report and detailed inhibitory effects of both compounds on PPA. Lineweaver-Burk plot revealed that the inhibition was a mixed-noncompetitive type, and only one molecule of inhibitor bound to the enzyme or to the enzyme-substrate complex. Kinetic constants calculated from secondary plots were in millimole range. Dissociation constants of enzyme-inhibitor complex （KEI） were 0.9 mM and 3.5 mM, respectively. Moreover, dissociation constants of enzyme-inhibitor-substrate complex （KESI） were 0.04 mM and 0.31 mM, respectively. These data indicated that the inhibition was more inclined to competitive to Gal-G2-α-CNP hydrolysis. Further molecular docking study manifested that hydrogen bonding formed between acarbose and aspartic acid （Asp300）, histidine （His305） and glycine （Gly3-6）, while hydrogen bonding was observed between chelidonine and glutamic acid （Glu233）, lysine （Lys200） and His305. In addition, rutaecarpine had only one hydrogen bond with Lys200. Our data indicated that chelidonine and rutaecarpine were two promising drug candidates, and chelidonine possessed stronger inhibitory effect compared with rutaecarpine.

Total synthesis of a hydrated aurone derivative

The total synthesis of a hydrated aurone derivative, 2-benzyl-4-methoxy-2,6-dihydroxybenzofuran-3（2H）-one, has been achieved for the first time with 2.4% overall yield. Using phloroglucinol as the starting material, the key steps included Friedel-Crafts acylation, Williamson synthesis, hydrogenolysis, aldol condensation, enolization and Rubottom oxidation.

Application of the HSAB principle for the quantitative analysis of nucleophilicity/basicity of organic compounds with lone-pair electrons

Based on the density functional theory,we described here a method to investigate the quantitative relationship between nucleophilicity/basicity and HSAB-theory-based properties of compounds with lone-pair electrons.Descriptors including global softness,Fukui function,local softness and local mulliken charge were calculated at SVWN/DN~* level of DFT with PC Spartan Pro.Nucleophilicity and basicity of 28 selected compounds were classified based on intensity.BP algorithm of artificial neural network(ANN) was employed to study the relationship between the descriptors and nucleophilicity/basicity.Cross-validation was carried out to avoid the over-fitting in training of ANN.A BP network was trained to quantify the relationship between HSAB-theory-based properties and nucleophilicity/basicity of compounds with lone-pair electrons.The results show that the prediction based on the network matches with the experimental results well.The local softness and Fukui function have a better relationship with nucleophilicity and local mulliken charge than with the basicity.The trained BP network could be utilized for predicting the nucleophilicity/basicity of compounds or functional groups with lone-pair electrons.