右旋邻氯扁桃酸分子印迹聚合物的制备及结合特性研究

以右旋邻氯扁桃酸为模板分子合成了具有高选择性的分子印迹聚合物作为手性分离材料 .紫外光谱研究说明在聚合开始之前模板分子与功能单体形成了配合物 ,并用Hyperchem软件模拟其分子结构 ,结合能分别为 -1 643 7× 1 0 4 J·mol- 1 和 -4 2 799× 1 0 4 J·mol- 1 .分子印迹聚合物对模板分子的结合量高于其它类似物 ,手性分离因子α达 1 76.Scatchard分析表明分子印迹聚合物在识别右旋邻氯扁桃酸分子过程中存在两类结合位点 ,与配合物模拟结构数目一致     

Synthesis of derivatives of <Emphasis Type="Italic">o</Emphasis>-aminoacetophenone and <Emphasis Type="Italic">o</Emphasis>-aminobenzyl alcohol

Oxidation of 2′-hydroxy-8-methylspiro[4H-benz-1,3-oxazin-2-one-6,1′-cyclopentane] or N-mesyl-2-(cyclopent-1-en-1-yl)-6-methylaniline provided the corresponding ketones. The rearrangement of these ketones oximes under treatment with thionyl chloride gave rise to nitriles of 5-(2-amino-3-methylphenyl)-5-oxopentanoic or 5-(2-methanesulfamido-3-methylphenyl)-5-hydroxypentanoic acids. By heating 5-(2-acetylamido-3-methylphenyl)-5-oxopentanoic acid with LiH in THF3-(2,8-dimethylquinol-4-on-3-yl)propanoic acid was obtained.     

Synthesis of 5-substituted 5-hydroxy-2-pyrrolidones, metabolites of the antipsychotic benzamide remoxipride

This paper describes the synthesis of 5-[(3-bromo-2,6-dimethoxybenzamido)-methyl]-5-hydroxy-2-pyrrolidon e (3) and its 1-ethyl analogue 2, two urinary metabolites of the dopamine D-2 antagonist remoxipride [1, (S)-3-bromo-N-[(1-ethyl-2-pyrrolidinyl)methyl]-2, 6-dimethoxybenzamide]. Two synthetic schemes leading to a common intermediate, 5-benzamido-4-oxopentanoic acid 4, were developed. This key intermediate permits conversion into either metabolite. Reaction of 4 with isobutyl chloroformate furnished a mixed carbonic anhydride, which upon treatment with ethylamine or ammonia gave the 4-oxopentanamides 5 and 6, respectively. Ring-closure afforded the corresponding 5-hydroxy-2-pyrrolidones 2 and 3.     

Anticancer Drugs ( Ⅳ )——New Derivatives of Podophyllotoxin

Four new derivatives of podophyllotoxin, N'-podophyllic acid-N-[3-(2, 2, 5, 5-te-tramethyl-pyrrolinenyloxy)] semicarbazide(GP-11, 6), podophyllic acid [3-(2,2,5,5-te-tramethyl-pyrrolinenyloxy)]hydrazone (GP-12, 7), podophyllic acid-[4-(2, 2, 6, 6-tetramethyl-1-hydroxy piperidine)]hydrazone(GP-1-OH, 8) and podophyllic acid[4-(2,2, 6, 6-tetramethyl piperidine)]hydrazone(GP-1-H, 9) were synthesized. The inhibition effect of the four new compounds on L-1210 cells were determined. The antitumor activity and toxicity of GP-1(2), GP-1-OH(8), GP-1-H(9) and VP-16-213(1) were discussed.     

Synthesis and Evaluation of Optical 2‐Benzyl‐5‐bromo‐4‐oxopentanoic Acids as Transition‐state Analog Inhibitors against Carboxypeptidase A

Both enantiomers of 2‐benzyl‐5‐bromo‐4‐oxopentanoic acid were prepared utilizing the diazo ketones as the key intermediates. The compounds were assayed for inhibitory activity against carboxypeptidase A (CPA, EC 3.4.17.1). The (R)‐form is 260‐fold more potent than the corresponding (S)‐form. The finding that (R)‐form, which belongs to the L‐series, is mostly responsible for the inhibitory activity accords with the substrate specificity of CPA. For comparison, both the optical forms of 2‐benzyl‐4‐oxopentanoic acid were also synthesized and evaluated as the inhibitors against CPA. These results reveal that the introduction of a bromo group at the α‐position of ketones can significantly enhance the electrophilicity of the carbonyl group. Further molecular docking study suggested that the gem‐diol form of the α‐bromo ketone, which mimics the transition state in the CPA catalytic process, could chelate the zinc ion in the active site of CPA and thus result in the strong inhibition.     

新型三氮烯试剂与阴离子表面活性剂相互作用的荧光光谱法研究

自制新型1-(5-萘酚-7-磺酸基)-3-[(4-偶氮苯基)苯基]-三氮烯(NASAPAPT)试剂作为荧光试剂,研究其与阴离子表面活性剂十二烷基苯磺酸钠(SDBS)的荧光性能.结果表明,NASAPAPT与SDBS产生荧光猝灭作用,在优化的实验条件下,测定SDBS的线性范围为2.52×10-8～1.06×10-6 mol,L-1内,检出限为1.93×10-8 moL·L-1.方法应用于环境水样中痕量SDBS的测定,回收率在98.39％～102.460％.计算了NASAPAPT与SDBS的热力学函数,表明它们之间主要靠范德华力结合.     

Mechanistic insight into the inactivation of carboxypeptidase A by alpha-benzyl-2-oxo-1,3-oxazolidine-4-acetic acid, a novel type of irreversible inhibitor for carboxypeptidase A with no stereospecificity

On the basis of the active site topology and enzymic catalytic mechanism of carboxypeptidase A (CPA), a prototypical zinc-containing proteolytic enzyme, alpha-benzyl-2-oxo-1,3-oxazolidine-4-acetic acid (1), was designed as a novel type of mechanism-based inactivator of the enzyme. All four possible stereoisomers of the inhibitor were synthesized in an enantiomerically pure form starting with optically active aspartic acid, and their CPA inhibitory activities were evaluated to find that surprisingly all of the four stereoisomers inhibit CPA in a time dependent manner. The inhibited enzyme did not regain its enzymic activity upon dialysis. The inactivations were prevented by 2-benzylsuccinic acid, a competitive inhibitor that is known to bind the active site of the enzyme. These kinetic results strongly support that the inactivators attach covalently to the enzyme at the active site. The analysis of ESI mass spectral data of the inactivated CPA ascertained the conclusion from the kinetic results. The values of second-order inhibitory rate constants (k(obs)/[I](o)) fall in the range of 1.7-3.6 M(-1) min(-1). The lack of stereospecificity shown in the inactivation led us to propose that the ring cleavage occurs by the nucleophilic attack at the 2-position rather than at the 5-position and the ring opening takes place in an addition-elimination mechanism. The tetrahedral transition state that would be generated in this pathway is thought to be stabilized by the active site zinc ion, which was supported by the PM3 semiemprical calculations. In addition, alpha-benzyl-2-oxo-1,3-oxazolidine-5-acetic acid (18), a structural isomer of 1 was also found to inactivate CPA in an irreversible manner, reinforcing the nucleophilic addition-elimination mechanism. The present study demonstrates that the transition state for the inactivation pathway plays a critical role in determining stereochemistry of the inactivation.     

Electrosynthesis of 5-amino-4-oxopentanoic acid hydrochloride

The electroreduction of methyl 5-nitro-4-oxopentanate was studied by means of a polarographic method and preparative electrolysis in acidic-alcoholic solutions. The effects of the following factors on the yield and quality of 5-amino-4-oxopentanoic acid hydrochloride were studied: the cathode material, amount of electricity, temperature, nature of the solvent, concentrations of the initial nitro compound and hydrochloric acid, and the cell design. It was shown by electrolysis at a controlled potential and in a galvanostatic mode that the products of methyl 5-nitro-4-oxopentanate electroreduction are hydroxyamino and amino compounds, and also ammonium chloride, nitromethane, methylhydroxylamine hydrochloride, and monomethylamine hydrochloride. Their ratio depends on the electrolysis conditions. The highest overall substance yield (61.1–66.0%) and current yield (68.1–68.6%) of 5-amino-4-oxopentanoic acid hydrochloride was achieved at a copper cathode in a filter-press cell. The content of the main substance in the electrochemically obtained samples of 5-amino-4-oxopentanoic acid was 89.5–91.0%.     

1-甲基-2-喹诺酮类衍生物的合成及其抗肿瘤活性

以喹啉类化合物为原料,经甲基化反应和氧化反应制得中间产物2-喹诺酮类化合物(2a~2c); 2a~2c经硝化反应制得7个硝化-2-喹诺酮类化合物{3a~3g); 3a, 3e~3g经移位取代反应合成了4个1-甲基化-4-氰化-2-喹诺酮类衍生物(4a, 4e~4g),其结构经¹H NMR, ¹³C NMR和HR-MS(EI)确证。采用MTT法评价了化合物对MCF-7, H1299, A549, PC-12, CT-26及HepG-2肿瘤细胞的抗增殖作用。研究结果表明：部分化合物对肿瘤细胞的抑制活性明显高于喹啉系列物,其中1,8-二甲基-3,5,7-三硝基-2-喹诺酮(3e)显著抑制六种肿瘤细胞的增殖,对A549的抑制活性最高,IC₅₀为2.05 μmol·L^-1; 1-甲基-6,8-二硝基-4-氰基-2-喹诺酮(4a)可选择性抑制A549和CT-26肿瘤细胞,IC₅₀分别为9.34 μmol·L^-1和18.43 μmol·L^-1。     

伊马替尼衍生物的合成及其抗肿瘤活性

以4-硝基-2-氨基甲苯为起始原料,经加成、缩合、环化和还原反应制得中间体N-(2-甲基-5-氨基苯基)-4-(3-吡啶基)嘧啶-2-胺(4),再与取代酰氯反应,合成了7个新型伊马替尼衍生物（5a~5g）,其结构经¹H NMR, ¹³C NMR和HR-MS 表征。采用四甲基偶氮唑盐(MTT)法考察了5对人肝癌细胞(HepG₂)、子宫颈癌细胞（Hela）、肺癌细胞（H460）和乳腺癌细胞（MCF-7）体外抑制活性。结果显示：5e体外抑制活性最优,其IC₅₀分别为10.90±1.00 μmol·L^-1; 8.51±0.90 μmol·L^-1; 13.15±1.11 μmol·L^-1; 14.75±0.78 μmol·L^-1。     

新型六氢吡啶-2,3-并吲哚化合物的合成及其抗肿瘤活性

以3-取代氧化吲哚与丙烯酸酯为原料,经Michael加成反应制得中间体--3-丙酸酯取代氧化吲哚（3a~3d）; 3a~3d与甲胺发生酰胺化反应制得3 丙酰胺取代氧化吲哚（4a~4d）; 4a~4d用氢化铝锂还原-环化,合成了4个六氢吡啶-2,3-并吲哚化合物(5a~5d）; 5a和5b用氢化铝锂还原合成了2个六氢吡啶-2,3-并吲哚化合物（6a和6b）, 5a～5d, 6a和6b均为新化合物,总产率42%～61%,其结构经¹H NMR, ¹³C NMR和HR-ESI-MS表征。采用MTT法研究了5a～5d, 6a和6b对人肺癌细胞（A549）,人前列腺（PC-3）和人白血病细胞（K562）的体外抗肿瘤活性。结果表明：5b对A549, PC 3和K562的抑制活性均较好,其IC₅₀分别为27.2μmol·L^-1, 37.5 μmol·L^-1和21.7 μmol·L^-1。     

Bioactive aromatic derivatives from endophytic fungus, Cytospora sp

Two new benzyl gamma-butyrolactone analogues, (R)-5-((S)-hydroxy(phenyl)-methyl)dihydrofuran-2(3H)-one (1) and its 6-acetate (2), and a new naphthalenone derivative (8), together with eight additional known aromatic derivatives, (S)-5-((S)-hydroxy(phenyl)-methyl)dihydrofuran-2(3H)-one (3), (S)-5-benzyl-dihydrofuran-2(3H)-one (4), 5-phenyl-4-oxopentanoic acid (5), gamma-oxo-benzenepentanoic acid methyl ester (6), 3-(2,5-dihydro-4-hydroxy-5-oxo-3-phenyl-2-furyl)propionic acid (7), (3R)-5-methylmellein (9), integracins A (10) and B (11) were isolated from Cytospora sp., an endophytic fungus isolated from Ilex canariensis from Gomera. The structures of these compounds were elucidated by detailed spectroscopic analysis, comparison with reported data, and chemical interconversion. The absolute configurations of the new compounds (1, 2, 8) were established on the basis of optical rotation or CD spectra analysis. Preliminary studies showed antimicrobial activity of these compounds against the fungi Microbotryum violaceum, Botrytis cinerea and Septoria tritici, the alga Chlorella fusca, and the bacterium Bacillus megaterium.     

异噁唑拼接吡咯螺环氧化吲哚化合物的合成及其抗肿瘤活性

以取代靛红,(E)-硝基异噁唑芳烯烃和苯基甘氨酸为原料,乙腈为溶剂,经1,3-偶极子3+2环加成反应合成了8个新型的异噁唑拼接吡咯螺环氧化吲哚化合物(3a~3h),产率41%~62%,d/r值为2∶1~10∶1,其结构经~1H NMR,~(13)C NMR和HR-ESI-MS表征。采用MTT法研究了3a~3h对人肺癌细胞(A549),人前列腺(PC-3)和人白血病细胞(K562)的体外抗肿瘤活性。结果表明:3a,3b和3c分别对K562,PC-3和A549具有较好的抑制活性,其对应的IC50为16.0μmol·L~(-1),21.2μmol·L~(-1)和24.4μmol·L~(-1),优于顺铂(26.1μmol·L~(-1),27.2μmol·L~(-1)和25.6μmol·L~(-1))。     

1/2,5-二取代吲唑-3-甲酰胺衍生物的合成及其抗肿瘤活性

以吲唑-3-羧酸为原料,依次经溴代和酯化反应制得中间体5-溴吲唑-3-羧酸甲酯(2);2经N-烷基化并原位水解生成1/2-取代-5-溴吲唑-3-羧酸(3);3与吡啶酮甲胺类化合物经缩合反应制得酰胺(4);4与芳基频哪醇硼酸酯发生Suzuki偶联反应合成了14个新型二取代吲唑-3-甲酰吡啶酮甲胺衍生物(5a~5n),收率26%~32%,其结构经~1H NMR,~(13)C NMR和HR-MS(ESI-TOF)表征。通过NOE差谱确证了取代基在吲唑氮原子上的取代位置。采用MTT法研究了5a~5n对人B淋巴瘤细胞(Ramos)、人黑色素瘤细胞(CHL-1,WM-266-4)和乳腺癌细胞(BT-474)的体外抗肿瘤活性。结果表明:5a,5b,5m对Ramos细胞、5a,5b,5l对WM-266-4细胞、5a,5b,5d,5e,5h,5j,5m,5n对CHL-1细胞和5a,5b,5d,5h,5m对BT-474细胞具有较好的抑制活性(IC5010.0μmol.L-1)。     

新型丙烯海松酸基双噻二唑化合物的合成及其抗真菌活性

松香与丙烯酸经Diels-Alder环加成反应制得丙烯海松酸(1); 将1转化为双酰氯后与2-氨基-5-取代苯基-1,3,4-噻二唑经-N-酰化反应合成了8个新型的丙烯海松酸基双噻二唑化合物(4a~4h),其结构经¹H NMR, ¹³C NMR, IR和元素分析表征。抗真菌活性测试结果表明,在用药量为50 μg·mL^-1时,4d(R=m-Cl)对苹果轮纹病菌、花生褐斑病菌和小麦赤霉病菌的抑制率分别为66.9%, 57.8%和52.9%。     

Design,synthesis and evaluation of bifunctional inhibitors of type II dehydroquinase

Inhibitors of type II dehydroquinase were designed to straddle the two distinct binding sites identified for the inhibitor (1S,3R,4R)-1,3,4-trihydroxy-5-cyclohexene-1-carboxylic acid and a glycerol molecule in a crystallographic study of the Streptomyces coelicolor enzyme. A number of compounds were designed to incorporate characteristics of both ligands. These analogues were synthesized from quinic acid, and were assayed against type I (Salmonella typhi) and type II (S. coelicolor) dehydroquinases. None of the analogues showed inhibition for type I dehydroquinase. Six of the analogues were shown to have inhibition constants in the micromolar to low millimolar range against the S. coelicolor type II dehydroquinase, while two showed no inhibition. The binding modes of the analogues in the active site of the S. coelicolor enzyme were studied by molecular docking with GOLD1.2. These studies suggest a binding mode where the ring is in a similar position to (1S,3R,4R)-1,3,4-trihydroxy-5-cyclohexene-1-carboxylic acid in the crystal structure and the side-chain occupies part of the glycerol binding-pocket.     

盐酸强力霉素分子印迹聚合物的制备及分子识别性能

以盐酸强力霉素(DC)为模板分子、甲基丙烯酸为功能单体、乙二醇二甲基丙烯酸酯为交联剂、四氢呋喃(THF)为溶剂.采用本体聚合法制备了DC的分子印迹聚合物.在水溶液中,采用平衡结合方法和Scatchard模型评价了该聚合物的结合特性及识别机理,并考察了DC分子印迹聚合物的选择性吸附能力.结果表明,在所研究的浓度范围内,D...     

新型噻吩并四氢吡啶类化合物的合成及其抗血小板聚集活性

噻吩并［3,2-c］四氢吡啶和噻吩并［2,3-c］四氢吡啶分别与取代苄溴(2a~2g)经取代反应后,用2 mol·L^-1氯化氢乙醚溶液成盐合成了噻吩并四氢吡啶衍生物(3b~3e, 3g和5a~5g);噻吩并［3,2-c］四氢吡啶酮与取代苄溴经取代反应,再与乙酸酐缩合,最后经2 mol·L^-1氯化氢乙醚溶液成盐合成了噻吩并四氢吡啶衍生物(7d, 7e, 7g~7i)。 3, 5和7均为新化合物,其结构经¹H NMR 和ESI-MS表征。大鼠体内抗血小板聚集活性研究结果表明：3, 5和7均有一定的抗血小板聚集活性,其中7d, 7h和7i的抑制率分别为66.2%, 86.8%和88.3%,活性优于阳性对照药噻氯匹啶。     

Reaction of 3-(o-chlorobenzylidene)-2,4-dioxopentanoic acid with hydroxylamine hydrochloride. Revised structure tor azeto[3,2-d]isoxazoline

Reaction of 3-(o-ehlorobenzylidene)-2,4-dioxopentanoic acid (1) with hydroxylamine hydro-chloride in acetic acid gave 5-(o-chlorophenyl)-3-methyl-4-(α-hydroxyimino)isoxazolineglyo-xylic acid (5) and 3-(o-chlorobenzylidene)-4-hydroxyimino-2-oxopentanoic acid (2) in 57% and 7% yields. Pyrolysis of 5 afforded 5-(o-chlorophenyl)-3-methylisoxazole-4-carbonitrile (8), cis- and trans-5-(o-chlorophenyl)-3-methylisoxazoline-4-carbonitriles (9,10), and 5-(o-chloro-phenyl)-3-methylisoxazoline-4-carboxamide (11).     

新型他克林-吲哚杂二联体的微波促进Husigen[3+2]环加成反应合成及生物活性

以吲哚-3-丙酸和吲哚-3-丁酸为原料,分别与炔丙胺发生缩合反应得到3-(丙酰丙炔胺)吲哚(4a)和3-(丁酰丙炔胺)吲哚(4b),然后4a和4b分别与9-(叠氮基乙基氨基)-1,2,3,4-四氢吖啶类衍生物5a～5c在微波辐射下发生Husigen[3+2]环加成反应得到12个新型乙酰胆碱酯酶抑制剂——他克林-吲哚杂二联体,其结构经NMR,IR和HRMS表征.初步生物活性测试表明,目标化合物均具有较强的乙酰胆碱酯酶抑制能力,其中化合物2b和2d抑制鱼鳐乙酰胆碱酯酶的IC50值分别为1.6和2.0 nmol.L-1,是6T6BA(IC50=11.0 nmol.L-1,鱼鳐)的6.9和5.5倍.