新型龙胆酸衍生物的合成及其抑制酪氨酸酶活性研究

为发现新型的美白活性化合物,以龙胆酸甲酯、卤代烃和α-羟基酸乙酯为原料,合成了10个未见文献报道的2-羟基-5-烷(H)氧基苯甲酸酯类衍生物(3a,3b和6a～6h),其结构经1H NMR,IR,MS和HRMS确认.初步生物活性测试结果表明6a,6b,6e和6f具有较强的抑制酪氨酸酶活性,进一步药理实验表明经取代改造后的6a～6h,其毒性和光学毒性都相对龙胆酸甲酯和氢醌更低.     

含L-乳酸基的聚丙三醇水凝胶的合成及性能

以L-乳酸和环氧氯丙烷等原料,设计、合成出含L-乳酸基的聚丙三醇水凝胶。用核磁共振碳谱、X-射线光电子能谱和扫描电镜表征了其结构和形貌。通过控制反应条件,合成了不同L-乳酸基含量和平衡溶胀率的聚丙三醇水凝胶。化学滴定分析表明,在选定的合成条件下,L-乳酸基的引入率约为86%,其含量可达到17%。溶胀实验表明,凝胶具有显著的pH、离子强度敏感性和快速、可逆的响应速率。体外释药实验显示,载药凝胶具有随溶胀环境pH变化的释药性能。     

双活性磺酸基蔗渣木聚糖对羟基苯甲酸酯的合成及活性模拟

以蔗渣木聚糖(BX)为主要原料、氨基三磺酸钠为酯化剂,在一步酯化合成磺酸基蔗渣木聚糖酯的基础上,利用磺酸基蔗渣木聚糖酯和对羟基苯甲酸进行二步酯化反应,合成了磺酸基蔗渣木聚糖对羟基苯甲酸酯,并考察了反应条件对酯化反应的影响,通过单因素实验确定了第二步酯化反应较佳的合成工艺条件.蔗渣木聚糖酯化改性前后的样品分别用FT-IR,DG-DTG和XRD进行了表征,并对该双酯化衍生物的分子进行了优化与活性模拟.结果表明:FT-IR证明双酯化产物含有磺酸基团和对羟基苯甲酸酯基团,TG-DTG分析表明该双酯化衍生物的热稳定性提高,XRD说明发生双酯化改性后分子排列的规整性提高,结晶度增加;活性模拟实现了磺酸基蔗渣木聚糖对羟基苯甲酸酯与艾滋病毒的对接.     

双氢青蒿素衍生物的研究进展

从醚类、酯类、杂原子取代C-10-O类等单活性基团衍生物和双活性基团衍生物两大类结构出 发,综述了1997后合成的双氢青蒿素衍生物及其合成方法,在生理活性研究方面发现双氢青蒿素衍生物除具有抗疟活性外,还具有抗肿瘤、抗血吸虫、抗孕、提高免疫力等其他生物与生理活性.     

斑蝥素衍生物的合成、抗肝癌活性及构效关系研究

斑蝥素衍生物具有结构多样性和良好的抗肝癌活性。本文以呋喃、顺丁烯二酸酐为原料,合成了35个斑蝥素衍生物。以顺铂为阳性对照药,经MTT法测试了所合成化合物对人肝癌HepG2细胞的体外抗肿瘤活性。结果表明,化合物6d、6f、6g、6h、6i的抗肝癌活性与顺铂相当,其中,斑蝥素酰亚胺类化合物具有较好的抗肝癌活性,且当取代基为吸电子基或含氮杂环时化合物显现出较强的抗肝癌活性,该类化合物具有潜在的抗肝癌应用价值。     

新型含亲水基的噻唑烷-4-酮衍生物的合成及HIV逆转录酶抑制活性

在微波辐射条件下合成了系列C-2或N-3位含酯基的噻唑烷-4-酮衍生物,经水解或还原得到含亲水基如羧基、羟基的衍生物.化合物通过艾滋病毒逆转酶(HIV-RT)试剂盒(比色法)评价了其酶抑制活性.活性结果表明,部分化合物如8a,8b,9a,9b和14c能有效地抑制HIV逆转酶的活性.其中在N-3嘧啶环5位连有乙基的化合物8a和9a的活性最高,IC50值分别为3.02和3.06μmol·L-1.构效关系表明亲水性基团的引入对HIV逆转录酶抑制活性影响不大,而N-3位嘧啶基更有利于噻唑烷-4-酮抗HIV活性.     

新型2-(2-氨基噻唑-4-基)-2-(Z)-甲氧亚胺基乙酸酯类衍生物的合成及其抑菌活性

以乙酰乙酸甲(乙)酯,醛和酰氯为主要原料,合成了8个2-(2-氨基噻唑-4-基)-2-(Z)-甲氧亚胺基乙酸酯类衍生物(其中6个未见文献报道),其结构经1H NMR,IR和MS表征.初步抑菌活性测试结果表明,在给药量为200 mg·L-1时,化合物对小麦赤霉病菌和马铃薯干腐病菌有较好的抑菌活性.     

新型含苯并噻唑基双酰胺衍生物的合成及其抗菌活性

以邻甲基苯甲酸和取代邻氨基苯甲酸为起始原料,设计并合成了10个未见文献报道的含苯并噻唑基双酰胺类衍生物,其结构经1H NMR,13C NMR,IR及元素分析表征。初步的抗菌活性测试结果表明,在500 mg.L-1浓度下部分化合物对黄瓜花叶病毒(CMV)有一定抑制作用。     

含肟酯类姜黄素衍生物的合成及其抗病毒活性

采用生物活性因子拼接法将肟酯引入单羰基姜黄素衍生物1,5-二取代芳基-1,4-戊二烯-3-酮中,合成了11个新型不对称1,5-二取代-1,4-戊二烯-3-酮肟酯类姜黄素衍生物,其结构经1H NMR,IR和元素分析表征.初步生物活性测试结果表明,部分化合物具有一定的抗黄瓜花叶病毒(CMV)活性.     

2-甲基-6-氯苯基磺酰脲衍生物的合成及生物活性

为探索磺酰脲类化合物的生物活性多样性,以商品化磺酰脲除草剂为基础,设计并合成了12个未见文献报道的2-甲基-6-氯苯基磺酰脲衍生物,通过1H NMR,13C NMR和HRMS确定了其结构.经盆栽法除草测试表明,目标化合物对双子叶靶标油菜和反枝苋具有优异的的除草活性,如5b,5i和5j对油菜和稗草的除草活性与氯磺隆和单嘧磺隆相当.离体抑菌实验表明,在50 mg·L-1剂量下,部分化合物对所测试植物性病菌具有不错的抑菌活性.     

Synthesis and Anticoagulant Activity of Bioisosteric Sulfonic‐Acid Analogues of the Antithrombin‐Binding Pentasaccharide Domain of Heparin

Two pentasaccharide sulfonic acids that were related to the antithrombin‐binding domain of heparin were prepared, in which two or three primary sulfate esters were replaced by sodium‐sulfonatomethyl moieties. The sulfonic‐acid groups were formed on a monosaccharide level and the obtained carbohydrate sulfonic‐acid esters were found to be excellent donors and acceptors in the glycosylation reactions. Throughout the synthesis, the hydroxy groups to be methylated were masked in the form of acetates and the hydroxy groups to be sulfated were masked with benzyl groups. The disulfonic‐acid analogue was prepared in a [2+3] block synthesis by using a trisaccharide disulfonic acid as an acceptor and a glucuronide disaccharide as a donor. For the synthesis of the pentasaccharide trisulfonic acid, a more‐efficient approach, which involved elongation of the trisaccharide acceptor with a non‐oxidized precursor of the glucuronic acid followed by post‐glycosidation oxidation at the tetrasaccharide level and a subsequent [1+4] coupling reaction, was elaborated. In vitro evaluation of the anticoagulant activity of these new sulfonic‐acid derivatives revealed that the disulfonate analogue inhibited the blood‐coagulation‐proteinase factor Xa with outstanding efficacy; however, the introduction of the third sulfonic‐acid moiety resulted in a notable decrease in the anti‐Xa activity. The difference in the biological activity of the disulfonic‐ and trisulfonic‐acid counterparts could be explained by the different conformation of their L ‐iduronic‐acid residues.     

Cytotoxic evaluation of semisynthetic ester and amide derivatives of oleanolic acid

Although a number of chemicals have been isolated from Lantana camara, only a few have been evaluated for their biological significance. As part of our drug discovery program for cytotoxic agents from Indian medicinal plants, roots of L. camara L. were chemically investigated, which resulted in the isolation and identification of a cytotoxic agent, oleanolic acid (1b) as a major constituent. Oleanolic acid was converted into six semi-synthetic ester (2-7) and seven amide (8-14) derivatives. The ester derivatives (2-7) showed 3-6 times more selective activity than 1b against the human ovarian cancer cell line (IGR-OV-1), while amide derivatives 8-14 showed 16-53 times more selective activity against the human lung cancer cell line (HOP-62). Structure activity relationship within the ester (2-7) and amide (8-14) derivatives are discussed.     

Synthesis,In vitro Coagulation Activities and Molecular Docking Studies on Three L-Histidine Amide Derivatives

Three novel L-histidine amide derivatives were synthesized and the corresponding chemical structures were characterized by means of melting point analysis, IR, MS, ¹H NMR as well as ¹³C NMR. The coagulation acti- vities of the compounds were evaluated by an MOE(molecular operating environment) docking technique and coagulation test. The results obtained from molecular docking show that the interactions between the compounds and thrombin exhibit procoagulant activity in combination with an improved combinatory effect. Moreover, the results of in vitro coagulation tests show that the L-histidine amide derivatives feature coagulant activities in common coagulation pathways. Compared with the blank control group, the optimal shortening rates of compounds 1―3 were 39.08%(0.5 mmol/L), 22.94%(1.0 mmol/L) and 15.38%(0.0625 mmol/L), respectively.     

侧链带有L-氨基酸乙酯的螺旋聚苯乙炔衍生物的手性识别能力研究

采用Rh(nbd)BPh4催化剂合成了3种侧链带有L-氨基酸乙酯的螺旋聚苯乙炔衍生物PPA-S-Phe、PPA-S-Leu和PPA-A-Leu,并将其涂覆在氨丙基硅胶上制备高效液相色谱(HPLC)手性固定相(CSP),研究其对7种对映体的手性识别能力.由于侧链手性基团或主链与手性基团之间的链接基团不同,PPA-S-Phe、PPA-S-Leu和PPA-A-Leu形成了不同的螺旋构象,并表现出对对映体不同的手性识别能力.PPA-S-Phe和PPA-S-Leu的主链与手性基团之间的链接基团均为磺酰胺基,侧链手性基团为L-亮氨酸乙酯的PPA-S-Leu的手性识别能力优于侧链手性基团为L-苯丙氨酸乙酯的PPA-S-Phe.PPA-S-Leu和PPA-A-Leu的侧链手性基团均为L-亮氨酸乙酯,以酰胺基为链接基团的PPA-A-Leu的手性识别能力明显优于以磺酰胺基为链接基团的PPA-S-Leu.螺旋聚苯乙炔主链与侧链手性基团之间的链接基团、侧链手性基团在手性识别中均发挥十分着重要作用.     

Design of heterogeneous catalysts via multiple active site positioning in organic-inorganic hybrid materials

Catalytic materials bearing multiple sulfonic acid functional groups and positioned at varying distances from one another on the surface of mesoporous solids are prepared to explore the effects that the spatial arrangement of active sites have on catalytic activity and selectivity. A series of organosiloxane precursors containing either disulfide or sulfonate ester functionalities (synthons of the eventual sulfonic acid groups) are synthesized. From these molecular precursors, a variety of organic-inorganic hybrid, mesostructured SBA-15 silica materials are prepared using a postsynthetic grafting procedure that leads to disulfide and sulfonate ester modified silicas: [Si]CH(2)CH(2)CH(2)SS-pyridyl, 2.SBA, [Si]CH(2)CH(2)CH(2)SSCH(2)CH(2)CH(2)[Si], 3.SBA, [Si]CH(2)CH(2)(C(6)H(4))(SO(2))OCH(2)CH(3), 4.SBA, and [Si]CH(2)CH(2)(C(6)H(4))(SO(2))OC(6)H(4)O(SO(2))(C(6)H(4))CH(2)CH(2)[Si], 6.SBA ([Si] = (tbd1;SiO)(x)()(RO)(3)(-)(x)()Si, where x = 1, 2). By subsequent chemical derivatization of the grafted species, thiol and sulfonic acid modified silicas are obtained. The materials are characterized by a variety of spectroscopic ((13)C and (29)Si CP MAS NMR, X-ray diffraction) and quantitative (TGA/DTA, elemental analysis, acid capacity titration) techniques. In all cases, the organic fragment of the precursor molecule is grafted onto the solid without measurable decomposition, and the precursors are, in general, attached to the surface of the mesoporous oxide by multiple siloxane bridges. The disulfide species 2.SBA and 3.SBA are reduced to the corresponding thiols 7.SBA and 8.SBA, respectively, and 4.SBA and 6.SBA are transformed to the aryl sulfonic acids 11.SBA and 12.SBA, respectively. 7.SBA and 8.SBA differ only in terms of the level of control of the spatial arrangement of the thiol groups. Both 7.SBA and 8.SBA are further modified by oxidation with hydrogen peroxide to produce the alkyl sulfonic acid modified materials 9.SBA and 10.SBA, respectively. The performances of the sulfonic acid containing SBA-15 silica materials (with the exception of 12.SBA) are tested as catalysts for the condensation reaction of phenol and acetone to bisphenol A. The alkyl sulfonic acid modified material 10.SBA derived from the cleavage and oxidation of the dipropyl disulfide modified material 3.SBA is more active than not only its monosite analogue 9.SBA, but also the presumably stronger acid aryl sulfonic acid material 11.SBA. It appears that a cooperative effect between two proximal functional groups may be operating in this reaction.     

胶束电动色谱柱上酶反应测定低分子量肝素的抗凝血活性

发展了一种基于胶束电动色谱（MEKC）结合柱上酶微反应的方法,用于测定低分子量肝素（LMWHs）的抗凝血活性。肝素与抗凝血酶Ⅲ（ATⅢ）结合后,将ATⅢ抑制凝血因子10（FXa）活性提高了约1000倍。通过测定FXa水解生色肽底物CPS产生的对硝基苯胺（p -NP）就可以测定FXa的活性。因此,通过LMWHs抑制FXa产生的对硝基苯胺的量就可以测定抗凝血活性。该方法将毛细管柱端作为微量的酶微反应器,以呋喃妥英（nitrofurantoin,NF）作为内标,依次将LMWHs溶液、ATⅢ溶液、FXa和CPS溶液导入毛细管柱端,反应物经过分子扩散、横向层流扩散混合和电压混合后反应。反应结束后,采用MEKC分离模式将产物对硝基苯胺与底物以及其他大分子分离,在其最大波长380 nm下测定产生对硝基苯胺的量,从而确定LMWHs的抗凝血活性。该方法具有自动化、重复性好、灵敏度高、样品消耗量少的优点,而且不受其他成分的干扰,可用于各种复杂样品（如血浆）中LMWHs抗FXa活性的监测。     

Synthesis of aryl sulfones via L-proline-promoted CuI-catalyzed coupling reaction of aryl halides with sulfinic acid salts

[reaction: see text] The CuI/L-proline sodium salt catalyzed coupling reaction of aryl halides with sulfinic acid salts readily occurs at 80-95 degrees C in DMSO to give the corresponding aryl sulfones in good to excellent yields. This process is well-tolerated by a wide range of functional groups including hydroxyl, amino, acetanilide, ketone, ester, and nitrile. Using this method, 4-phenylsulfonyl- and 4-methanesulfonyl-substituted L-phenylalanine derivatives are prepared.     

酶法合成L-4-甲砜基苯丙氨酸

以4-甲砜基苯丙酮酸和L-天冬氨酸为底物, 利用重组大肠杆菌DM204(pGEX-KG-aspC/BL21)表达的天冬氨酸转氨酶酶法转化得到了L-4-甲砜基苯丙氨酸, 优化得到的酶法最佳转化条件为: 转化温度37 ℃, 反应体系pH=8, 底物4-甲砜基苯丙酮酸质量分数8%, 质量分数0.6%的吐温80和10-4 mol/L Mg2+对酶活有促进作用. 在最佳工艺条件下经过12 h酶促反应, 4-甲砜基苯丙酮酸摩尔转化率达95%. 本研究利用化学生物法制备了L-4-甲砜基苯丙氨酸, 为制备其它天然氨基酸衍生物提供了新思路.     

Synthesis and anticoagulant activity of bioisosteric sulfonic-Acid analogues of the antithrombin-binding pentasaccharide domain of heparin

Two pentasaccharide sulfonic acids that were related to the antithrombin-binding domain of heparin were prepared, in which two or three primary sulfate esters were replaced by sodium-sulfonatomethyl moieties. The sulfonic-acid groups were formed on a monosaccharide level and the obtained carbohydrate sulfonic-acid esters were found to be excellent donors and acceptors in the glycosylation reactions. Throughout the synthesis, the hydroxy groups to be methylated were masked in the form of acetates and the hydroxy groups to be sulfated were masked with benzyl groups. The disulfonic-acid analogue was prepared in a [2+3] block synthesis by using a trisaccharide disulfonic acid as an acceptor and a glucuronide disaccharide as a donor. For the synthesis of the pentasaccharide trisulfonic acid, a more-efficient approach, which involved elongation of the trisaccharide acceptor with a non-oxidized precursor of the glucuronic acid followed by post-glycosidation oxidation at the tetrasaccharide level and a subsequent [1+4] coupling reaction, was elaborated. In vitro evaluation of the anticoagulant activity of these new sulfonic-acid derivatives revealed that the disulfonate analogue inhibited the blood-coagulation-proteinase factor?Xa with outstanding efficacy; however, the introduction of the third sulfonic-acid moiety resulted in a notable decrease in the anti-Xa activity. The difference in the biological activity of the disulfonic- and trisulfonic-acid counterparts could be explained by the different conformation of their L-iduronic-acid residues.