Studies on biodegradable poly(hexano-6-lactone) fibers 1. Structure and properties of drawn poly(hexano-6-lactone) fibers

Using high molecular weight (M-n=80,000) Poly(hexano-6-lactone) (PCL'), tough and high tenacity PCL monofilaments with various draw ratios (undrawn to 9 times drawn) were prepared by melt-spinning. The relationship between microstructure and properties of the PCL fibers is described in this current IUPAC Technical Report. Analysis of microstructure of the drawn PCL fibers by wide-angle X-ray diffraction revealed typical c-axis orientation with an increase in crystallinity. It was also supported by sonic velocity measurements. The thermal, mechanical, and dynamic mechanical properties of the PCL fibers were affected significantly by draw ratio. DSC thermograms showed that the melting temperature and the enthalpy of fusion increased with draw ratio. The temperature dependence curves of dynamic viscoelasticity showed that the temperature at tan delta peak of alpha dispersion corresponding to the glass transition temperature shifted toward higher temperature and the peak value of tan delta decreased with draw ratio. The dynamic storage modulus and the sonic modulus increased with draw ratio. These results are due to the increase in crystallinity and molecular orientation with drawing, and are responsible for an increase in tensile tenacity as well as knot tenacity of the PCL fibers.

A new sesquiterpene lactone of Notoseris henryi

A new guaianolide, notoserolide E, along with nine known compounds was isolated from the Chinese endemic plant of Notoseris henryi ( Dunn) Shih and its structure was elucidated by means of spectroscopic evidence.

Ⅰ 虎杖聚酮类化合物生物合成相关基因的克隆及功能分析 Ⅱ 高山红景天酪醇生物合成代谢途径机制分析

Ⅰ 虎杖聚酮类化合物生物合成相关基因的克隆及功能分析 虎杖 (Polygonum cuspidatum Sieb. et Zucc) 属于蓼科蓼属多年生草本植物，在中国和日本民间曾被广泛用于动脉粥样硬化、高血压、咳嗽、化脓性皮肤炎以及淋病的治疗，具有祛风利湿、散瘀定痛、止咳化痰等功效。而在现代医学上最令人瞩目和具有发展前景的是其在抗肿瘤、心血管保护、抗氧化方面的作用，相关疗效主要来自于虎杖中结构迥异、种类丰富的聚酮化合物及其衍生物资源。这些聚酮类化合物主要包括蒽醌、大黄素、大黄素-甲醚、大黄酚、芪类以及类黄酮化合物等。其中，大部分聚酮类化合物生物合成途径机制尚不明确，但可以肯定的是植物类型III聚酮合酶type III polyketide synthases (PKSs) 在这些聚酮化合物的生物合成起始反应中行使着关键的作用。因此，除了我们所熟悉的类黄酮化合物、芪类化合物之外，进一步分离和分析虎杖中其它重要聚酮类化合物生物合成所涉及的类型III聚酮合酶基因的是非常值得期待的。 目前，已经有14个植物类型III PKS基因被克隆和功能分析。植物类型III PKS的共同特征包括基因结构、序列相似性、保守的活性中心、酶学性质以及共同的催化机制等。显花植物（裸子植物和被子植物）中，植物类型III PKS的基因结构绝对保守，除了一个早期报道的金鱼草（Antirrhinum majus）查尔酮合酶chalcone synthase (CHS) 含有第二个内含子外，迄今为止所有已知的植物类型III PKS基因均含有一个内含子且该内含子位置保守。有趣的是，在本研究中，两个含有3个内含子的类型III PKS基因从虎杖中被分离，且两个基因3个内含子的位置完全保守，这是三内含子类型III PKS基因首次得到分离。除了新奇的基因结构外，体外功能分析显示上述两个基因还具有特殊的酶学性质和功能。 本论文围绕上述2个三内含子基因开展了以下工作： 虎杖中一个由三内含子基因编码的新型类型III聚酮合酶 一个类型III PKS的cDNA及其相应的基因（PcPKS2）从药用植物虎杖中被克隆。序列分析结果表明，PcPKS2的开放阅读框被3个内含子分隔，这是一个出人意料的发现，因为截至到目前为止，除了金鱼草一个CHS基因外，所有已知的类型III PKS基因均在固定位置上含有一个内含子。除了特殊的基因结构外，PcPKS2显示了一些有趣的特性：(i) CHS“守卫”苯丙氨酸——Phe215和Phe265在PcPKS2中双双缺失，它们分别被亮氨酸和半胱氨酸取代;(ii) 体外功能分析结果表明，当酶促反应体系的pH值为6.5-8.5时，大肠杆菌中过表达的重组PcPKS2高效地合成丁烯酮非环化产物——4-香豆酰甘油酸内酯（4-coumaroyltriacetic acid lactone (CTAL)）为主产物，而丙烯酮非环化产物bis-noryangonin (BNY) 以及苯亚甲基丙酮为副产物;而当酶促反应体系的pH值为9.0时，PcPKS2高效地合成苯亚甲基丙酮为主产物，而CTAL、BNY为副产物。另外，除了上述3种产物外，在不同的pH条件下，还有痕量的柚皮素查尔酮能被检测到。此外，在4-香豆酰辅酶A（4-coumaroyl-CoA）的类似化合物中，除了4-香豆酰辅酶A外，只有feruloyl-CoA能够被PcPKS2接受作为起始底物。PcPKS2不接受脂肪酰辅酶A——异丁酰基辅酶A（isobutyryl-CoA）、异戊酰基辅酶A（isovaleryl-CoA）以及乙酰辅酶A（acetyl-CoA）作为起始底物。Southern blot杂交结果表明，在虎杖基因组中存在2-4个PcPKS2基因的拷贝。Northern blot杂交结果表明，在根茎和幼叶中，PcPKS2表达量很高，而在根中无表达。叶中的PcPKS2的表达受病原菌诱导，但不受伤诱导。 虎杖中一个编码双功能类型III聚酮合酶的三内含子基因的鉴定 显花植物中，所有已知的类型III PKS 基因均含有一个内含子且位置绝对保守。本研究中，综合运用PCR技术，从富含聚酮类化合物的植物虎杖中克隆得到一个类型III PKS 基因（PcPKS1）及其cDNA。序列分析结果表明，PcPKS1含有3个内含子。系统发育分析结果表明，PcPKS1与其它植物的CHSs归为一类。然而，体外功能分析结果表明，当酶促反应体系pH值为7.0时，大肠杆菌中过表达的重组PcPKS1高效地合成柚皮素查尔酮（naringenin）为单一产物;而当pH值为9.0时，苯亚甲基丙酮（p-hydroxybenzalacetone）几乎为重组PcPKS1的唯一产物。后续的研究表明，与典型的CHSs相比，PcPKS1具有另外一些不同的特点：在pH值为9.0时（PcPKS1的苯亚甲基丙酮合成活性最适pH值），在4-香豆酰辅酶A的类似化合物中，只有feruloyl-CoA能够被PcPKS1接受作为起始底物。与CHSs展现出的对脂肪酰辅酶A宽泛的底物特异性不同，在不同的pH条件下，PcPKS1不接受异丁酰基辅酶A（isobutyryl-CoA）、异戊酰基辅酶A（isovaleryl-CoA）以及乙酰辅酶A（acetyl-CoA）作为起始底物。以上数据指出重组PcPKS1是一个具有查尔酮合酶（CHS）和苯亚甲基丙酮合酶（BAS）活性的双功能酶。Southern blot杂交结果表明，在虎杖基因组中存在2-4个PcPKS1基因的拷贝。Northern blot杂交结果表明，PcPKS1可能在防御病原菌和草食动物方面起着重要作用。PcPKS1和PcPKS2共同从虎杖中被分离的事实极有可能暗示了苯丁烷类化合物（phenylbutanoid）及其衍生物存在于虎杖中。 Ⅱ 高山红景天酪醇生物合成代谢途径机制研究 高山红景天（Rhodiola sachalinensis A. Bor）是景天科（Crassulaceae）红景天属多年生草本植物，作为一种适应原性中草药在中国的应用史已经超过800年。最近红景天提取物作为一种重要的商业药用制剂资源，其应用遍及欧洲、亚洲和美国，其主要治疗范围包括抗变应性和消炎，提高心理机敏性等。目前已经非常明确，红景天甙（salidroside）和甙元酪醇（tyrosol）是红景天属植物的主要功效成分，主要分布于这类植物的根中并且具有抗缺氧、抗疲劳、延缓衰老、预防紫外线辐射伤害等功效。红景天甙为酪醇8-O-β-D葡萄糖甙，是酪醇在葡萄糖基转移酶UDP-glucosyltransferase (UGT) 的催化下糖基化后形成的，可以认为是酪醇在植物体内的贮存形式。酪醇作为一种重要的活性分子，同样存在于橄榄树和葡萄酒中。 虽然已经非常明确酪醇来自于莽草酸代谢途径，然而其具体的生物合成途径及其调控仍不明确。总结以往的报道，在酪醇的生物合成上主要存在两种观点：一是酪醇可能来自于苯丙烷代谢途径产生的4-香豆酸（4-coumaric acid）前体;二是来自于酪氨酸的酪胺（tyramine）可能是酪醇生物合成的直接前体。我们的工作兴趣主要围绕着鉴别高山红景天中的酪醇生物合成途径展开： 高山红景天内源苯丙氨酸解氨酶PALrs1的过表达对红景天甙积累的影响 红景天甙是来自于药用植物高山红景天的一种适应原性新型药物，其生物合成途径可能起始于苯丙氨酸或酪氨酸。由于高山红景天野生植物资源的匮乏和相对含量很低，阐明红景天甙的生物合成途径对于增加红景天甙的供给至关重要。在我们以前的工作中，运用cDNA末端快速扩增技术（RACE），一个编码苯丙氨酸解氨酶phenylalanine ammonia-lyase (PAL)的cDNA从高山红景天中被克隆，命名为PALrs1。在本研究中，PALrs1置于35S启动子+Ω增强子序列的控制下通过农杆菌（Agrobacterium tumefaciens）介导法转化回高山红景天。PCR 和 PCR–Southern blot分析结果表明，PALrs1已经整合到了转基因植物的基因组上。Northern blot杂交结果表明，PALrs1已经获得在转录水平上的高水平表达。与预期的结果相同，高效液相色谱High-performance liquid chromatography (HPLC)测定结果显示PALrs1的过表达引起4-香豆酸含量增长3.3倍。然而，与之相反的是，酪醇和红景天甙含量与对照相比反而分别下降4.7和7.7倍。此外，我们发现PALrs1的过表达造成酪氨酸含量下降2.6倍。这些数据暗示着PALrs1的过表达和4-香豆酸的积累并不能促进酪醇的生物合成。酪醇，作为一种苯乙烷类衍生物并非来自苯丙氨酸，而酪氨酸含量的下降则极有可能是酪醇生物合成和红景天甙积累大规模下降的直接原因。

Concentricolide, an anti-HIV agent from the ascomycete Daldinia concentrica

A novel benzofuran lactone, named concentricolide (=rel-(6R)-6-ethylbenzo[2.1-b:3,4-c']difuran-8(6H)-one; 1), was isolated along with four known compounds (friedelin, cytochalasin L-696.474, armillaramide, and russulamide) from the fruiting bodies of the

野桂花的化学成分研究

首次从野桂花（Osmanthus yunnanensis Fr. P. S. Green）地上部分95%乙醇提取物中通过色谱分离得到20个化合物, 其中化合物20为新化合物。基于波谱数据它们被鉴定为(E)-阿魏酸二十烷基酯(1)、β-谷甾醇(2)、羽扇豆醇(3)、齐墩果酸(4)、7-oxo-β-sitosterol(5)、乙酰齐墩果酸(6)、(6′-O-palmitoyl)-sitosterol 3-O-β-D-glucoside(7)、rotundioic acid(8)、地榆糖甙Ⅱ(9)、27-O-(E)-对羟基肉桂酰-28-齐墩果酸(10)、27-O-(Z)-对羟基肉桂酰-28-齐墩果酸(11)、hycandinic acid ester(12)、绿原酸丁酯(13)、4,5-二咖啡酰奎尼酸丁酯(14)、4,5-dihydroxyprenyl caffeate(15)、28-O-β-D-glucopyranosyl rotundioic acid (16)、4-(6-O-caffeoyl-β-D-glucopyranosyloxy)-5-hydroxyprenyl caffeate (aohada-glycoside C, 17)、 4-β-D-glucopyranosyloxy-5-hydroxy-prenyl caffeate (aohada-glycoside A, 18)、β-胡萝卜甙(19)以及3-[O-β-D-(6-O-咖啡酰吡喃葡萄糖)]-甲基-2-烯-γ-内酯 (20)。化合物13、14、15和17有较强的α-葡萄糖甙酶抑制活性。当浓度为1 mg/ml时，它们对α-葡萄糖甙酶的抑制分别为61.5%、95.5%、72.1%、62.6%，活性高于阿卡波糖。 综述了木犀属植物化学成分及1993年以来苯丙素甙类化合物活性研究进展。 Twenty compounds were isolated from the 95% ethanol extract of the aerial parts of Osmanthus yunnanensis Fr. P. S. Green by chromatography for the first time. On the basis of spectral data, they were identified as (E)-ferulic acid eicosyl ester (1), β-sitosterol (2), lupenol (3), oleanolic acid (4), 7-oxo-β-sitosterol (5), acetyloleanolic acid (6), (6′-O-palmitoyl)-sitosterol 3-O-β-D-glucoside (7), rotundioic acid (8), ziyu glycosideⅡ (9), 3β-hydroxy-27-p-(E)-coumaroyloxy-olean-12-en-28-oic acid (10), 3β-hydroxy-27-p-(Z)-coumaroyloxyolean-12-en-28-oic acid (11), hycandinic acid ester (12), chlorogenic acid butyl ester (13), 4,5-di-O-caffeoylquinic acid butyl ester (14), 4,5-dihydroxyprenyl caffeate (15), 28-O-β-D-glucopyranosyl rotundioic acid (16), 4-(6-O-caffeoyl-β-D-glucopyranosyloxy)-5-hydroxyprenyl caffeate (aohada- glycoside C, 17), 4-β-D-glucopyranosyloxy-5-hydroxyprenyl caffeate (aohada- glycoside A, 18), β-daucosterol(19) and 3-[O-β-D-(6-O-caffeoylglucopyranosyl)]- methyl-2-en-γ-lactone (20). Compound 20 is a new one. Compounds 13, 14, 15 and 17 inhibit α-glucosidase with corresponding inhibitory rate of 61.5%, 95.5%, 72.1% and 62.6% at a concentration of 1 mg/ml, higher than acarbose. The chemical studies on Osmanthus genus and bioactivities of phenylpropanoid glycosides were summarized.

滇金足草、凋缨菊和长喙吴萸的化学成分研究

本论文对滇金足草（Goldfussia yunnanensis）、凋缨菊（Camchaya loloana）和长喙吴萸（Evodia vestia）的化学成分进行了研究，通过色谱分离得到40个化合物。主要基于波谱数据鉴定了它们的结构，其中10个为新化合物。 1．从滇金足草地上枝叶的95%乙醇提取物中共分离鉴定了16个化合物：泽漆内酯A（1）、18-羟基泽漆内酯A（2）、18-氧代泽漆内酯A（3）、18-羟基-3-O-β-D-吡喃葡萄糖-泽漆内酯A（4）、3-O-β-D-吡喃葡萄糖-泽漆内酯A（5）、3-O-β-D-吡喃半乳糖-泽漆内酯A（6）、6-E-肉桂酰哈巴俄苷（7）、E-哈巴俄苷（8）、5，6-异亚丙二氧基哈巴俄苷（9）、β-谷甾醇（10）、β-胡萝卜苷（11）、齐墩果酸（12）、肉桂酸（13）、麦角固醇（14）、硬脂酸（15）和丁二酸（16）。其中2-7为新化合物。5，6-异亚丙二氧基哈巴俄苷（9）以人工产物形式得到。 2．从凋缨菊地上枝叶的95%乙醇提取物中分离并鉴定了13个化合物：凋缨菊内酯A~C (17-19)、1β-乙酰基凋缨菊内酯C(20)、b-谷甾醇（10）、β-胡萝卜苷（11）、羽扇豆醇（21）、桦木醇（22）、桦木酸（23）、芥子醇（24）、紫丁香苷（25）、咖啡酸（26）和熊果酸（27）。其中化合物17-20为桉叶烷内酯类新化合物。化合物17、18、20对细胞株HepG2的GI50依次为7.80、7.08、4.99 µg/mL。 3．从长喙吴萸（E. vestia）地上枝叶的95%乙醇提取物中分离并鉴定了13个化合物：佛手内酯（28）、花椒毒素（29）、异茴芹内酯（30）、七叶内酯（31）、东莨宕素（32）、瑞香素（33）、异紫花前胡内酯(34)、茵芋碱（35）、山刈碱（36）、白鲜碱（37）、黄柏酮（38）、柠檬苦素（39）和对羟基苯甲醛（40）。 4．综述了1990—2007年期间从菊科植物中发现的桉叶烷-12，6内酯的化学结构、生物活性、生物转化及化学合成方面的研究进展。 Phytochemical investigation on Goldfussia yunnanensis, Camchaya loloana, and Evodia vestia, led to the isolation of 40 compounds, 10 of which were new ones. 1. Six new compounds were isolation from 95% ethanolic extract of the aerial parts of G. yunnanensis, and identified as 18-hydroxyhelioscopinolide A (2), 18-oxohelioscopinolide A (3), 18-hydroxy-3-O-β-D-glucopyranosylhelioscopinolide A (4), 3-O-β-D-glucopyranosylhelioscopinolide A (5),3-O-β-D-Galactopyranosyl helioscopinolide A (6), 6-O-trans-cinnamoyl E-harpagoside (7). The known compounds isolated were helioscopinolide A (1), E-harpagoside A (8), 5,6-isopropylidene E-harpagoside A (9), β-sitosterol (10), β-daucosterol (11), oleanolic acid (12), cinnamic acid (13), ergosterol (14), stearic acid (15) and succinic acid (16). Compound 9 was an artifact. 2. Four new compounds, loloanolides A – C (17 - 19) and 1β-acetoxy-loloanolide C (20), were isolation from 95% ethanolic extract of the aerial parts of C. loloana. The known ones were β-sitosterol (10), β-daucosterol (11), lupeol (21), betulin (22), betulinic acid (23), sinapyl (24), syringin (25), caffeic acid (26) and ursolic acid (27). The GI50 values of compounds 17, 18 and 20 to HepG2 cell line were 7.80, 7.08 and 4.99 µg/mL, respectively. 3. Thirteen were isolated from 95% ethanolic extract of the aerial parts of E. vestia for the first time. They were determined to be bergapten (28), xanthotoxin (29), isopimpinellin (30), esculetin (31), scopoletin (32), daphnetin (33), marmesin (34), skimmianine (35), confusameline (36), dictamine (37), obacunone (38), limonin (39) and p-hydroxy phenyl aldehyde (40). 4. The structures, biological activities, biotransformation and chemical syntheses of eudesmane-12, 6-olides from the Asteraceae during 1990-2007 were reviewed.

Progress in the chemistry of spirodilactone and its derivations

Spirodilactones are a series of compounds with the structures of spiro-carbon and lactone which result in the special physical and chemical characters of Spirodilactones, In this paper the advance in the methods of synthesis, derivative reaction, chrial resolution, polymer synthesis of the most representative aspects for spirodi-gamma -butylactone and its derivations , were summarized described.

Polyimides from 3,3 '-dioxo-[1,1 ']-spirodiphthalan-5,5 ',6,6 '-tetracarboxylic dianhydride

A novel dianhydride, 3,3'-dioxo-[1,1']-spirodiphthalan-5,5',6,6'-tetracarboxlic dianhydride, was synthesized and used as a monomer to prepare polyimides with several diamines via a conventional two-stage procedure. The intermediate poly(amic-acid)s had inherent viscosities of 0.84-1.71 dL/g and could be thermally converted into lightly yellow, transparent, flexible and tough films. Films cast from chemically imidized polyimides were transparent and colorless. The glass transition temperatures (Tg) were > 400 degrees C, and the 5% weight-loss temperatures were > 420 degrees C in N-2 and in air. The solubilities of these polyimides in various solvents were evaluated. The mechanical properties of some polyimides were also tested. (C) 1999 Elsevier Science Ltd. All rights reserved.

A New Triterpenoid from Amoora dasyclada

Five compounds were isolated from the EtOH extraction of the stem of Amoora dasyclada (How et T. Chen) C. Y. Wu (Meliaceae). On the basis of spectroscopic methods, their structures were elucidated as 24, 25-epoxy-tirucall-7-ene-3, 23-dione (1), 24, 25, 26, 27-tetranortirucall-7-ene-3-oxo-23(21)-lactone (2), taraxerone (3), taraxerol (4) and b-sitosterol (5). Among them, compound 1 was a new triterpenoid, compounds 3-5 were firstly obtained from this plant; compound 2, an tetranortriterpenoid, was firstly isolated from natural sources, and its NMR data were assigned for the first time. Moreover, the D7-bond and the Me-14 in compound 2 were never changed, which has never been found in other tetranortriterpenoids. And the biosynthetic pathway of tetranortriterpenoid was further discussed.

Docking and molecular dynamics study on the inhibitory activity of coumarins on aldose reductase

In order to explore the inhibitory mechanism of coumarins toward aldose reductase (ALR2), AutoDock and Gromacs software were used for docking and molecular dynamics studies on 14 coumarins (CM) and ALR2 protease. The docking results indicate that residues TYR48, HIS110, and TRP111 construct the active pocket of ALR2 and, besides van der Waals and hydrophobic interaction, CM mainly interact with ALR2 by forming hydrogen bonds to cause inhibitory behavior. Except for CM1, all the other coumarins take the lactone part as acceptor to build up the hydrogen bond network with active-pocket residues. Unlike CM3, which has two comparable binding modes with ALR2, most coumarins only have one dominant orientation in their binding sites. The molecular dynamics calculation, based on the docking results, implies that the orientations of CM in the active pocket show different stabilities. Orientation of CM1 and CM3a take an unstable binding mode with ALR2; their conformations and RMSDs relative to ALR2 change a lot with the dynamic process. While the remaining CM are always hydrogen-bonded with residues TYR48 and HIS110 through the carbonyl O atom of the lactone group during the whole process, they retain the original binding mode and gradually reach dynamic equilibrium.

Docking and molecular dynamics studies toward the binding of new natural phenolic marine inhibitors and aldose reductase

Phenolic marine natural product is a kind of new potential aldose reductase inhibitors (ARIs). In order to investigate the binding mode and inhibition mechanism, molecular docking and dynamics studies were performed to explore the interactions of six phenolic inhibitors with human aldose reductase (hALR2). Considering physiological environment, all the neutral and other two ionized states of each phenolic inhibitor were adopted in the simulation. The calculations indicate that all the inhibitors are able to form stable hydrogen bonds with the hALR2 active pocket which is mainly constructed by residues TYR48, HIS110 and TRP111, and they impose the inhibition effect by occupying the active space. In all inhibitors, only La and its two ionized derivatives La_ion1 and La_ion2, in which neither of the ortho-hydrogens of 3-hydroxyl is substituted by Br, bind with hALR2 active residues using the terminal 3-hydroxyl. While, all the other inhibitors, at least one of whose ortho-sites of 3- and 6-hydroxyls are substituted by Br substituent which take much electron-withdrawing effect and steric hindrance, bind with hALR2 through the lactone group. This means that the Br substituent can effectively regulate the binding modes of phenolic inhibitors. Although the lactone bound inhibitors have relatively high RMSD values, our dynamics study shows that both binding modes are of high stability. For each inhibitor molecule, the ionization does not change its original binding mode, but it does gradually increase the binding free energy, which reveals that besides hydrogen bonds, the electrostatic effect is also important to the inhibitor–hALR2 interaction.