浆果楝中的新木脂素

从浆果楝（Cipadessa baccifera）中分离得到两个木脂素,其化学结构通过波谱方法鉴定为：（-）-9′-O-（E）-coumarate-5,5′-dimethoxylariciresinol（1）和（＋）-9′-O-（E）-feruloyl-5,5′-dimethoxylariciresinol（2）。其中化合物1为新化合物。     

刺五加有效成分及体外抑制二酰基甘油酰基转移酶活性研究

本文为研究刺五加(Acanthopanax senticosus Harms)的化学成分及其抑制二酰基甘油酰基转移酶(DGAT)活性。刺五加用75%乙醇提取,经硅胶、ODS、半制备HPLC进行分离纯化,结合理化性质、波谱数据鉴定化合物的结构。得到12个化合物分别鉴定为赤式-愈创木基丙三醇-β-O-4′-二羟基松柏醇(1)、(E)-3-(2,2-dimethyl-2H-chromen-6-yl)prop-2-enal(2)、7′E-4,9-dihydroxy-3,3′,5′-trimethoxy-8,4′-oxyneolign-7′-en-9′-al(3)、5-甲氧基去氧双松柏醇(4)、去氧双松柏醇(5)、5,5′-二甲氧基落叶松脂素(6)、5,5′-二甲氧基开环异落叶松树脂酚(7)、(7′S,8′S)-4′-O-甲基黄花菜木脂素(8)、(+)-9′-O-(Z)-阿魏酰-5,5′-二甲氧基落叶松脂素(9)、(+)-9′-O-(E)阿魏酰-5,5′-二甲氧基落叶松脂素(10)、大豆苷(11)和3′-甲氧基大豆苷(12)。其中化合物1～3和8～10为首次从该植物中分离得到。化合物1、3～7、9和10对DGAT1活性具有抑制作用,其IC_(50)值范围在81.5±1.2到123.2±1.1μM之间。     

芒果叶化学成分研究 II

为探讨芒果(Mangifera indica L.)的化学成分,从芒果叶的70%乙醇提取物中分离鉴定了13个化合物,经波谱分析,分别鉴定为:(–)-secoisolariciresinol-9′-O-D-glucopyranoside(1)、7S,8R-erythro-4,7,9-trihydroxy-3,3′-dimethoxy-8-O-4′-neolignan-9′-O-β-D-glucopyranoside(2)、7R,8R-threo-4,7,9-trihydroxy-3,3′-dimethoxy-8-O-4′-neolignan-9′-O-β-D-glucopyranoside(3)、(7R/S,8R)-7,8-dihydro-9′-hydroxyl-3′-methoxyl-8-hydroxymethyl-7-(4-hydroxy-3-methoxyphenyl)-1′-benzofuranpropanol 9′-O-β-D-glucopyranoside(4)、citrusin D(5)、丁香苷(6)、2,6-二甲氧基-4-羟基苯基-1-O-β-D-葡萄糖苷(7)、原儿茶酸(8)、没食子酸(9)、没食子酸甲酯(10)、没食子酸乙酯(11)、4,5-二羟基-3-甲氧基苯甲酸(12)、β-胡萝卜苷(13)。其中化合物1～7和12为首次从芒果属植物中分离得到。     

星状凤毛菊的化学成分研究

采用各种填料的色谱柱层析方法从药用植物星状凤毛菊(Saussurea stella Maxim)的全草中分离纯化出15个化合物,经波谱分析将它们的化学结构分别鉴定为2-甲氧基-4-羟基苯甲醛(1)、3-(3-甲氧基苯基)丙烯醛(2)、松脂素-4′-O-β-葡萄糖苷(3)、胡萝卜苷(4)、木犀草素(5)、金合欢素(6)、洋芹素(7)、日本椴苷(8)、3′-甲氧基木犀草素-7-O-β-葡萄糖苷(9)、洋芹素-7-O-β-葡萄糖苷(10)、槲皮素-3-O-α-L-鼠李糖苷(11)、山奈素3-O-α-L-鼠李糖苷(12)、槲皮素-5-O-β-葡萄糖苷(13)、4′-甲氧基槲皮素-5-O-β葡萄糖苷(14)和3-甲氧基山奈素-6-O-β葡萄糖苷(15)。其中化合物1～5、9～10和13～15是首次从该种植物中分离得到。     

连香树树皮化学成分的研究

从连香树（Cercidiphyllum japonicum Sieb. et Zucc.）树皮中分离到8个化合物。其中7个为黄酮醇,1个为酚酸类成分。经理化测定和波谱解析,分别鉴定为5,7-二羟基-3,8,4′-三甲氧基黄酮 (Ⅰ)、3,5,7-三羟基-8,4′-二甲氧基黄酮 (Ⅱ)、5,7,4′-三羟基-3,8-二甲氧基黄酮 (Ⅲ)、3,5,7,4′-四羟基-8-甲氧基黄酮 (Ⅳ)、3,5,7,4′-四羟基黄酮 (Ⅴ)、5,7-二羟基-8,4′-二甲氧基黄酮-3-O-葡萄糖甙 (Ⅶ)、5,7,4′-三羟基-8-甲氧基黄酮-3-O-葡萄糖甙 (Ⅷ)和没食子酸乙酯 (Ⅵ)。其中化合物Ⅶ为未见报道的新化合物。除化合物Ⅴ外,其余化合物均为首次从该属植物中分得。     

火绒草的苯丙素类成分

采用含水乙醇提取、三氯甲烷脱色、正丁醇萃取和多种色谱分离方法,从新疆产菊科植物火绒草(Lentopodium lenotopodioides)全草中获得8个苯丙素类化合物。通过波谱数据分析,分别鉴定为二氢去氢二松柏醇4-O-β-D-葡萄糖苷(1)、二氢去氢二松柏醇9′-O-β-D-葡萄糖苷(2)、去氢二松柏醇9′-O-β-D-葡萄糖苷(3)、去氢二松柏醇9′-甲醚-4-O-β-D-葡萄糖苷(4)、(-)-松脂醇4-O-β-D-葡萄糖苷(5)、(-)-杜仲树脂酚4-O-β-D-葡萄糖苷(6)、枸橼苦素C(7)和咖啡酸(8)。化合物2~7为首次从该植物中报道。在500μmol L~(-1)浓度下,这些化合物对α-葡萄糖苷酶的抑制率均低于50%。     

青蕨植物化学成分的研究

从青蕨根部的乙酸乙酯提取物中分离得到4个化合物。通过化学及波谱分析鉴定其结构为：saucerneol D(1),dehydrogoniothalamin(2),1-acetoxyl-2-piperonyl-6-[6-methoxyl-piperonyl]3,7-dioxabicyclo-[3,3,0]-octane(3) and 5,5′-dihydroxy-3-methoxy-6,8,3″,3″-tetramethylpyran-(3′,4′)flavone-7-O-[β—D—apiofuranosyl-(1→6)]-β-D-glucopyranoside(4)。其中化合物(4)为新化合物,化合物(1)为首次从该属植物中分离得到。     

刺桑皮正丁醇部位化学成分研究

为研究刺桑(Taxotrophis ilicifolia)皮正丁醇部位的化学成分，该研究采用硅胶、ODS、Sephadex LH-20、反相半制备高效液相等色谱法对刺桑皮正丁醇萃取部位进行分离纯化，并综合理化性质及波谱数据鉴定其化合物的结构。结果表明：从刺桑皮正丁醇萃取物中分离得到16个化合物，分别鉴定为icariside E5 (1)、裂环异落叶松脂醇-9-O-β-吡喃葡萄糖苷(2)、2,4,6-三甲氧基苯酚-1-O-β-D-葡萄糖苷(3)、9-O-β-glucopyranosyl trans-cinnamyl alcohol (4)、3,4,5-三甲氧基苯酚-1-O-β-呋喃芹糖基-(1″→6′)-β-吡喃葡萄糖苷(5)、3-羟基-4,5-二甲氧基苯酚-β-D-吡喃葡萄糖苷(6)、2,6-二甲氧基-4-羟基苯酚-1-O-β-D-吡喃葡萄糖苷(7)、isotachioside (8)、ficuscarpanoside A (9)、uridine (10)、methyl syringate 4-O-β-D-glucopyranoside (11)、3,4,5-三甲氧基苯酚-β-D-吡喃...     

墨西哥落羽杉的化学成分

从墨西哥落羽杉(Taxodium mucronatum)枝叶中首次分离得到10个化合物,通过MS与NMR等方法将它们分别鉴定为quercetin 3′-methoxy-3-O-β-D-galactopyranoside(1),quercetin 3′-methoxy-3-O-β-D-arabinopyrano-side(2),quercetin 3′-methoxy-3-O-α-L-arabinofuranoside(3),quercetin(4),avicularin(5),quercetin 3-O-β-D-ga-lactopyranoside(6),(7′S,8′R)-4,7′-epoxy-3,3′-dimethoxy-4,9,3′,4′,9′-lignanepentol-4′-O-β-D-glucopyranoside(7),(7′S,8′S)-3,3′-dimethoxy-9,4′,9′-trihydroxy-4,8′-oxyneolignan-7′-O-β-D-glucopyranside(8),methyl shikimate(9)和β-sitosterol(10)。     

仙茅的化学成分研究

从仙茅(Curculigo orchioides Gaertn．)根茎的乙醇提取物中分离鉴定了7个己知化合物,它们是：eureuligoside I(1),oreinol glueoside(2),3,3′,5,5′-tetramethoxy-7,9′：7′,9-diepoxy-lignan-4,4′-di-O-β-D-glucopyranoside(3),3-hydroxy-5-methyl-phenol-1-O-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside](4),2,3,4,7-tetramethoxyxanthone(5),1,3,7-trimethylxanthine(6),daueosterol(7)。其中化合物3～7均为首次从该植物中分离得到。     

Sex pheromone of the butterbur borer, Ostrinia zaguliaevi

The sex pheromone blend of the butterbur borer, Ostrinia zaguliaevi (Lepidoptera: Pyralidae) was analyzed by means of gas chromatography-electroantennographic detection (GC-EAD), GC-mass spectrometry and a series of wind-tunnel bioassays. Four EAD-active compounds were detected in the female sex pheromone gland extract, and these were identified as tetradecyl acetate (14:OAc), (Z)-9-tetradecenyl acetate (Z9-14:OAc), (E)-11-tetradecenyl acetate (E11-14:OAc) and (Z)-11-tetradecenyl acetate (Z11-14:OAc). The average amounts ± s.d. of the four compounds in a single sex pheromone gland were 7.9±3.7 ng, 10.1±3.2 ng, 1.1±0.5 ng and 11.6±5.1 ng, respectively. In a wind-tunnel bioassay, the ternary blend of Z9-, E11- and Z11-14:OAc at a ratio found in the sex pheromone gland (45:5:50) elicited the same behavioral responses from the males as did virgin females and pheromone gland extract. Removal of any single compound from the ternary blend significantly diminished the pheromonal activity, whereas addition of 14:OAc to the ternary blend had no effect on the males' behavioral responses. Therefore, it was concluded that the sex pheromone blend of O. zaguliaevi is composed of Z9-14:OAc, E11-14:OAc and Z11-14:OAc at a ratio of 45:5:50.     

Identification and functional characterization of sex pheromone receptors in beet armyworm Spodoptera exigua (Hübner)

In moths, males can detect a distinct blend of several pheromone components by specialized olfactory receptor neurons (ORNs) on the antennae. Four candidate pheromone receptors (PR) with seven transmembrane domains were identified by homology cloning from the antennae of Spodoptera exigua (Sexi). Phylogenetic analyses reveal that all four odorant receptors (OR) belong to pheromone receptor subtypes. Expression patterns revealed that PRs were male-specific in the antenna except for SexiOR11, which was female antenna-biased. Functional analyses of these PRs were conducted using heterologous expression in Xenopus oocytes. SexiOR13 and SexiOR16 were all broadly activated by multiple pheromone components. SexiOR13 responded robustly to the critical pheromone component, Z9, E12-14:OAc and the minor pheromone component, Z9-14:OAc at a concentration of 10^?4 M. Dose-response studies indicate that SexiOR13 was approximately 4 times more sensitive to Z9,E12-14:OAc (EC50 = 3.158 × 10^?6 M) compared to Z9-14:OAc (EC50 = 1.203 × 10^?5 M). While, SexiOR16 responded robustly to the secondary pheromone component Z9-14:OH with high sensitivity (EC50 = 9.690 × 10^?7 M). However, similar tests of the five pheromones with SexiOR6 and SexiOR11 failed to elicit any response. These results provide basic knowledge to further advance research on the molecular mechanisms of pheromone reception.     

Sex pheromone of Etiella behrii, a pod borer of soybean in Indonesia: identification and field attraction

Four EAG-active components were detected in GC-EAG analyses of hexane extracts from virgin Etiella behrii (Zeller) (Lepidoptera: Pyralidae) females. These components were identified as dodecyl acetate (12:Ac), (E)-9-dodecenyl acetate (E9-12:Ac), either (Z)-9- or (E)-11-tetradecenyl acetate (Z9- or E11-14:Ac), and (Z)-11-tetradecenyl acetate (Z11-14:Ac) by comparison of retention indices on both nonpolar and polar GC columns. The available extract was insufficient for further GC-MS or other chemical analyses (<0.2 ng/female). In field tests carried out in East Java, a 10:90 mixture of E9-12:Ac and Z11-14:Ac showed attractiveness to male moths and addition of 12:Ac and/or E11-14:Ac significantly increased the trap catches while addition of Z9-14:Ac showed no significant effect. Maximum attraction was obtained with 5.35 or 10.7 g/rubber septum of a mixture of E9-12:Ac, Z11-14:Ac, 12:Ac and E11-14:Ac at the ratio of 10:90:0.7:6.3, respectively. The role of pheromone blends in species discrimination between E. behrii and the related E. zinckenella (Treitschke) is discussed.     

Synthesis, regioselective hydrogenolysis, partial hydrogenation, and conformational study of dioxane and dioxolane-type (9′-anthracenyl)methylene acetals of sugars

Dioxane-type (9′-anthracenyl)methylene acetal of methyl 2,3-di-O-methyl-α-d-glucopyranoside was cleaved with LiAlH₄/AlCl₃ (3:1) or with Na(CN)BH₃-HCl regioselectively to provide the 4- or 6-O-(9′-anthracenyl)methyl ether, respectively. Hydrogenolytic reaction of the exo and endo isomers of dioxolane-type acetals proved to be directed by the configuration of the acetalic carbon as well as by the intramolecular participation of the adjacent-free hydroxyl; ring-opening reaction of the endo isomer of the methyl 2,3-O-(9′-anthracenyl)methylene-α-l-rhamnopyranoside took place with complete selectivity resulting in the axial (9′-anthracenyl)methyl ether, whereas a 1:1 mixture of the axial and equatorial ethers was formed upon the same reaction of the exo isomer. Catalytic hydrogenation of the sugar acetals resulted in (9′,10′-dihydro-9′-anthracenyl)methylene derivatives without affecting the acetalic center. High-temperature molecular dynamics simulations and DFT (Density Functional Theory) geometry optimizations were carried out to study the conformation of the dioxane-type (9′,10′-dihydro-9′-anthracenyl)methylene acetal.     

A crtA-related gene from Flavobacterium P99-3 encodes a novel carotenoid 2-hydroxylase involved in myxol biosynthesis

A genomic DNA fragment with carotenogenic genes involved in myxol biosynthesis (3′,4′-didehydro-1′,2′-dihydro-β,ψ-carotene-3,1′,2′-triol) was cloned from Flavobacterium P99-3. It contains a gene highly homologous to crtA from purple bacteria encoding there an acyclic carotenoid 2-ketolase. Since no ketolation step is involved in myxol biosynthesis, the function of crtA-OH from Flavobacterium was assigned by complementation in Escherichia coli engineered to synthesize demethylspheroidene and 1′-hydroxy-demethylspheroidene. Upon co-expression of crtA-OH, the formation of 2-hydroxy derivatives of both carotenoids assigns CrtA-OH as a novel carotenoid hydroxylase. The gene was used to re-construct myxol biosynthesis in E. coli successfully. Additionally, 1′,2′-dihydroxytorulene and 1,2,1′-trihydroxy-3,4,3′,4′-tetradehydrolycopene were obtained. Their generation demonstrates that a new class of 2-hydroxy carotenoids can now be pursued by genetic engineering in E. coli.     

The excision of 3′ penultimate errors by DNA polymerase I and its role in endonuclease V-mediated DNA repair

Deamination of adenine can occur spontaneously under physiological conditions, and is enhanced by exposure of DNA to ionizing radiation, UV light, nitrous acid, or heat, generating the highly mutagenic lesion of deoxyinosine in DNA. Such DNA lesions tends to generate A:T to G:C transition mutations if unrepaired. In Escherichia coli, deoxyinosine is primarily removed through a repair pathway initiated by endonuclease V (endo V). In this study, we compared the repair of three mutagenic deoxyinosine lesions of A-I, G-I, and T-I using E. coli cell-free extracts as well as reconstituted protein system. We found that 3′-5′ exonuclease activity of DNA polymerase I (pol I) was very important for processing all deoxyinosine lesions. To understand the nature of pol I in removing damaged nucleotides, we systemically analyzed its proofreading to 12 possible mismatches 3′-penultimate of a nick, a configuration that represents a repair intermediate generated by endo V. The results showed all mismatches as well as deoxyinosine at the 3′ penultimate site were corrected with similar efficiency. This study strongly supports for the idea that the 3′-5′ exonuclease activity of E. coli pol I is the primary exonuclease activity for removing 3′-penultimate deoxyinosines derived from endo V nicking reaction.     

Acid phosphatase in Enteromorpha

Extracts of the alga Enteromorpha linza hydrolysed glucose-6-phosphate, p-nitrophenylphosphate 2′-, 3′-, and 5′-adenosine monophosphates with an optimum at pH 5. Cytidine and uridine-5′-nucleoside diphosphates, and 2′-, and 3′-adenosine monophosphates were relatively poorly hydrolysed. Zn²⁺ (10 mM) inhibited the hydrolysis of all substrates, whereas Mg²⁺ (10 mM) may be stimulatory. It is suggested that the hydrolysis of these phosphomonoesters was due to the activity of a non-specific acid phosphatase (orthophosphoric monoester phosphohydrolase, E.C. 3.1.3.2).     

Synthesis and inhibitory activity of thymidine analogues targeting Mycobacterium tuberculosis thymidine monophosphate kinase

We report on Mycobacterium tuberculosis thymidine monophosphate kinase (TMPKmt) inhibitory activities of a series of new 3′- and 5′-modified thymidine analogues including α- and β-derivatives. In addition, several analogues were synthesized in which the 4-oxygen was replaced by a more lipophilic sulfur atom to probe the influence of this modification on TMPKmt inhibitory activity. Several compounds showed an inhibitory potency in the low micromolar range, with the 5′-arylthiourea 4-thio-α-thymidine analogue being the most active one (K_i = 0.17 μM). This compound was capable of inhibiting mycobacteria growth at a concentration of 25 μg/mL.     

Pyrenocine C,A phytotoxin-related metabolite produced by onion pink root fungus,Pyrenochaeta terrestris

The structure of pyrenocine C, a new metabolite isolated from onion pink root fungus, Pyrenochaeta terrestris (Hansen) has been elucidated as (±)-(2′E)-5-(1′-hydroxybut-2′-enyl)-4-methoxy-6-methyl-2-pyrone by spectroscopic methods and chemical correlation with pyrenocine A.