(Ga,Mn,N) compounds growth with mass-analyzed low energy dual ion beam deposition

The (Ga,Mn,N) samples were grown by the implantation of low-energy Mn ions into GaN/Al2O3 substrate at different elevated substrate temperatures with mass-analyzed low-energy dual ion beam deposition system. Auger electron spectroscopy depth profile of samples grown at different substrate temperatures indicates that the Mn ions reach deeper in samples with higher substrate temperatures. Clear X-ray diffraction peak from (Ga,Mn)N is observed in samples grown at the higher substrate temperature. It indicates that under optimized substrate temperature and annealing conditions the solid solution (Ga,Mn)N phase in samples was formed with the same lattice structure as GaN and different lattice constant. (C) 2003 Elsevier Science B.V. All rights reserved.

(Ga,Mn,As) compounds grown on semi-insulating GaAs with mass-analyzed low energy dual ion beam depositionw

The (Ga,Mn,As) compounds were obtained by the implantation of Mn ions into semi-insulating GaAs substrate with mass-analyzed low energy dual ion beam deposition technique. Auger electron spectroscopy depth profile of a typical sample grown at the substrate temperature of 250degreesC showed that the Mn ions were successfully implanted into GaAs substrate with the implantation depth of 160 nm. X-ray diffraction was employed for the structural analyses of all samples. The experimental results were greatly affected by the substrate temperature. Ga5.2Mn was obtained in the sample grown at the substrate temperature of 250degreesC. Ga5.2Mn, Ga5Mn8 and Mn3Ga were obtained in the sample grown at the substrate temperature of 400degreesC. However, there is no new phase in the sample grown at the substrate temperature of 200degreesC. The sample grown at 400degreesC was annealed at 840degreesC. In this annealed sample Mn3Ga disappeared, Ga5Mn8 tended to disappear,Ga5.2Mn crystallized better and a new phase of Mn2As was generated. (C) 2002 Elsevier Science B,V. All rights reserved.

Syntheses, crystallographic and magnetic properties of Nd3Fe29-xCrx and other associated compounds

A systematic study of syntheses and magnetic properties of the Nd-3 Fe29-xCrx (x=4.5, 4.7, 5.0, and 5.5) compounds has been performed. The single-phase compounds of Nd3Fe29-xCrx can be formed in the range 4.5 less than or equal to x less than or equal to 5.5. The Curie temperature Tc, the saturation magnetization M-S at 4.2 K, the anisotropy field H-A at 4.2 K and room temperature, and the intra-sublattice exchange coupling parameter j(FeFe) at 4.2 K for the Nd3Fe29-xCrx compounds decrease with increasing Cr composition from x=4.5 to 5.5, respectively. Nitrogenation and carbonation, unlike hydrogenation, result mainly in improvements of the Curie temperature, the saturation magnetization and the anisotropy field at 4.2 K and room temperature for the Nd3Fe29-xCrx compounds compared with their parent compounds.

Photoluminescence enhancement of porous silicon by organic cyano compounds

A pronounced photoluminescence enhancement on chemically oxidized porous silicon was induced by a series of organic cyano compounds including 1,2-dicyanoethylene (CE), 1,3-dicyanobenzene (1,3-CB), 1,4-dicyanobenzene (1,4-CB), 1-cyanonaphthalene (1-CN), and 9-cyanoanthracene (9-CA). Photoluminescence enhancement effects were reversible for all compounds studies in this work. A dependence of photoluminescence enhancement on the steric effect and the electronic characteristics of these compounds and the structure of the porous silicon substrates were analyzed in terms of the photoluminescence enhancing factors. Surface chemical composition examined by Fourier transform infrared (FTIR) spectra demonstrated that the surface Si-H bonds were not changed and no new luminescent compounds were formed on porous silicon surface during adsorption of cyano compounds. A mechanism based on induced surface states acting as radiative recombination centers by cyano compounds adsorption was suggested.

Chemical Constituents from the Leaves and Stems of Schisandra lancifolia

A new nortriterpenoid, 20-hydroxymicrandilactone D (1) and a novel lignan glycoside, lancilignanside A (2) were isolated from leaves and stems of Schisandra lancifolia, together with three known nortriterpenoids (3—5) and nine known phenolics (6—14). The structures of new compounds 1 and 2 were determined by detailed analysis of their 1D and 2D NMR spectra, and chemical evidences. In addition, compounds 1—2, 6—7, and 9—11 showed anti-human immunodeficiency virus (HIV)-1 activities with 50% effective concentration (EC50) in the range of 3.0—99.0m g/ml. Compound 12 was not bioactive in this assay with EC50 more than 200m g/ml.

A colorimetric assay for screening microcystin class compounds in aquatic systems

Secondary metabolites produced by water-blooming cyanobacteria in eutrophic waters include some potent hepatotoxins, These compounds also have tumour-promoting properties, attributable to their inhibition and activation of protein phosphatases and kinases respectively. The inhibitory effect of these toxins on protein phosphatases have been employed in a commonly used radiometric assay, involving the use of a P-32-labeled substrate, for the detection and quantitation of these compounds. This paper investigates and describes a colorimetric method in which the activity of protein phosphatase 2A is determined by measuring the rate of colour production from the release of yellow p-nitrophenol using p-nitrophenyl phosphate as the substrate. Results of this study suggest that the colorimetric protein phosphatase inhibition assay is a simple, inexpensive tool for screening substances that may have tumour-promoting characteristics in aquatic systems. The detection limit of the colorimetric method is comparable to the radiometric assay. (C) 1998 Elsevier Science Ltd. All rights reserved.

四种药用植物的化学成分及芍药苷的微生物转化研究

本学位论文共有5章。第一章报道白芍的化学成分及芍药苷的微生物转化研究成果；第二章报道天山雪莲的化学成分研究；第三章报道两面针的化学成分研究；第四章报道通关藤的化学成分研究成果；第五章概述了花椒属植物中最近十年报道的新化合物及药理研究情况。 在第1章的第一部分报道了白芍（Paeonia lactiflora Pall.）的化学成分。我们采用正、反相硅胶柱层析等各种分离方法，从白芍的干燥根中共分离出14个化合物，其中1个为新化合物，其结构通过波谱分析证实为没食子酰白芍苷，另外还有2个为首次从该植物中分离得到。第二部分报道了芍药苷的微生物转化生产芍药苷代谢素-I的研究，从15株厌氧菌中筛选出10株有转化活性的菌株，其中短乳杆菌Lactobacillus brevis AS1.12的转化活性最好，对其转化条件进行了初步的筛选，确定了相对合理的转化工艺。 在第2章报道了天山雪莲（Saussurea involucrate Kar.et Kir.）全草乙醇提取物化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化和MS、NMR等波谱解析，共分离鉴定了28个化合物，结构类型分属于黄酮、倍半萜和木脂素等，其中2个新倍半萜化合物的结构分别表征为6α-羟基云木香酸6-β-D-吡喃葡萄糖苷和11βH-11,13-二氢去氢云木香内酯8α-O-(6′-乙酰)-β-D-吡喃葡萄糖苷。 第3章报道了两面针（Zanthoxylum nitidum （Roxb.）DC.）干燥根的乙醇提取物化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化和MS、NMR等波谱解析以及X-射线单晶衍射，共分离鉴定了16个生物碱，结构类型分属于苯并啡啶类、喹啉类和阿朴啡类等，其中2个新苯并啡啶类生物碱的结构分别表征为二聚双氢两面针碱和丙酮基双氢崖定椒碱。 第4章报道了通关藤（Marsdenia tenacissima (Roxb.) Wight et Arn.）水提取物化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化和MS、NMR等波谱解析以及X-射线单晶衍射，共分离鉴定了14个化合物，结构类型均属于C21多羟基甾醇，其中4个新化合物tenacigenoside A, tenacigenoside B, tenacigenoside C和tenacigenoside D的结构分别表征为3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-17β-tenacigenin B (62), 3-O-2,6- dideoxy-4-O-methyl-D-lyxo-hexopyranosly-11α-O- methylbutyryl-12β-O-acetyl-tenacigenin B (63), 3-O-6-deoxy-3-O-methyl-β-D- allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α-O-tigloyl-tenacigenin C (64)和3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α-O-2- methylbutyryl-tenacigenin C (65)。 第5章概述了花椒属植物的化学成分及药理活性研究进展。 This dissertation consists of 5 chapters. The first chapter elaborate the phytochemical investigation of Paeonia lactiflora Pall., and microbial transformation of paeoniforin. The second, third and four chapters elaborate the phytochemical investigation of Saussurea involucrate Kar.et Kir., Zanthoxylum nitidum (Roxb.) DC. and Marsdenia tenacissima (Roxb.) Wight et Arn., respectively. Chapter 5 is a review on chemical constituents and bioactivities of Zanthoxylum species. The part one of chapter 1 focus on the isolation and identification of chemical constituents from P. lactiflora. Fourteen compounds were isolated from the roots of P. lactiflora by repeat column chromatography over normal and reversed phase silica gel. Among them, one is a new compound and the structure was suggested as galloyl-albiflorin by spectral evidence. In addition, two compounds were firstly reported in this plant. The part 2 is about microbial transformation of paeoniforin. Chapters 2, 3 and 4 were isolations and identifications of chemical constituents from S. involucrate, Z. nitidum and M. tenacissima, respectively. From the aerial parts of S. involucrate, 28 compounds including 7 flavonoids and 13 sesquiterpenoids were isolated and identified. Among them, 2 new compounds were characterized as 6α-hydroxycostic acid 6-β-D-glucoside and 11βH-11,13-dihydrodehydro- costuslactone 8α-O-(6'-acetyl)-β-D-glucoside, respectively, by means of spectroscopic analysis. Otherwise, 11 ones were firstly reported from this plant. The third chapter is about the phytochemical investigation of Z. nitidum. Sixteen compounds were isolated and identified. Among them, 2 new benzophenanthridine alkaloids were characterized as 8-acetonyldihydrofagaridine and 1,3-bis(8-dihydronitidinyl)-acetone by spectroscopic analysis. The fourth chapter is about the phytochemical investigation of M. tenacissima. Fourteen compounds were isolated and identified. Among them, 4 new compounds, tenacigenosides A~D, were characterized as 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-17β- tenacigenin B, 3-O-2,6-dideoxy-4-O-methyl-D-lyxo-hexopyranosly-11α-O-methyl butyryl-12β-O-acetyl-tenacigenin B, 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl- (1→4)-β-D-oleandropyranosyl-11α-O-tigloyl-tenacigenin C, and 3-O-6-deoxy-3-O- methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α-O-2-methylbutyryl- tenacigenin C. Chapter 5 is a review on recent progress in bioactive constituents from plants of Zanthoxylum species.

五枫藤、小驳骨和川西茶藨的化学成分研究

八月瓜属植物五枫藤(Holboellia latifolia Wall.)和驳骨草属植物小驳骨(Gendarussa vulgaris Nees)均为药用植物, 前者化学成分研究不深入, 后者的化学成分未见报道。川西茶藨(Ribes takare D. Don)为茶藨子属植物, 没有化学成分的报道。本论文对三个植物的化学成分和活性成分进行了研究, 主要通过色谱方法分离得到了48 个化合物, 采用波谱分析或与已知标准品对照等手段鉴定了它们的结构, 其中有1 个新的原小檗碱类化合物和3 个新的联苯类化合物,发现了具有细胞毒活性和α-葡萄糖苷酶抑制活性的化合物。1、从五枫藤地上部分的95%乙醇提取物中分离得到了12 个化合物: 五加苷K (1)、hederagenin 3-O- α-L-rhamnopyranosyl-(1→2)- α-L-arabinopyranoside (2)、β-萘乙酸(3) 、3-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-α-L-arabinopyranosyl oleanolic acid 28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (4) 、3-O- α-L-rhamnopyranosyl-(1→2)-O- β- D-glucopyranosyl-(1→2)- α-L-arabinopyranosyl oleanolic acid (5) 、3-O-( β-D-glucopyranosiduronic acid)-oleanolic acid 28-O- β-D-glucopyranoside (6)、lup-20(29)-en-3-one (7)、lupeol (8)、β-谷甾醇(9)、齐墩果酸(10)、乌苏酸(11)、β-胡萝卜苷(12)。化合物1 对Lu-06、N-04 和Bre-04 癌细胞株的GI50 分别是0.77µg/mL、1.26 µg/mL 和1.55 µg/mL, 化合物2 对N-04 癌细胞株的GI50 为2.44 µg/mL。2、从小驳骨地上部分的95%乙醇提取物中分离得到了1 个原小檗碱类新化合物13-hydroxyl gusanlung A (25), β-谷甾醇(9)、齐敦果酸(10)、β-胡萝卜苷(12)、棕榈酸(1-)甘油酯(13)、棕榈酸(14)、阿苯哒唑(15)、阿苯哒唑砜(16)、阿苯哒唑亚砜(17)、aurantiamide acetate (18)、华良姜素(19)、芫花素(20)、(-)-丁香树酯醇(21)、gusanlung B (22) 、eupteleasaponinsⅤ acetate (23)、gusanlungA (24)、刺五加苷E (26)、岩白菜素(27)、咖啡酸(28)。化合物25 对肝癌细胞株(HepG2) 的GI50 为2.08 µg/mL。3、从川西茶藨地上部分的95%乙醇提取物中分离鉴定了22 个化合物: β-谷甾醇(9) 、β- 胡萝卜苷(12) 、O-acetyloleanolic aldehyde (29),4,7,8-trimethoxy-2,3-methylenedioxydibenzofuran (30) 、3', 5-dimethoxy-3, 4-methylenedioxybiphenyl (31) 、桦木醇(32) 、6,7-dimethoxy-1-methyl-3,4-dihydroquinolin-2-one (33)、3'-hydroxy-5-methoxy-3,4-methylenedioxybiphenyl (34) 、7-hydroxy-4,8-dimethoxy-2,3-methylenedioxydibenzofuran (35)、桦木醛(36)、没食子酸(37) 、6β- 羟基-4- 烯-3- 酮- 豆甾醇(38) 、5α, 8α-epidioxy-(22E,24R)-ergosta-6, 22-dien-3β-ol (39)、verrucofortine (40)、6-methoxycalpogoniumisoflavone A (41)、2-羟基二苯甲酮(42)、桦木酸(43), 3, 5-二甲氧基苯甲酸-4-O-β-D-吡喃葡萄糖苷(44)、洋芹素(45)、刺槐素(46)、水杨酸(47)、洋芹素-5-O- β-D-葡萄糖苷(48), 化合物30、31 和35 为新的联苯化合物。化合物30的α-葡萄糖苷酶抑制率为10.2% (1.00 mg/mL); 化合物35 的抑制率为17.2% (1.00mg/mL)。4、综述了1960 年以来原小檗碱类化合物药理活性研究进展。 Plants Holboellia latifolia Wall and Gendarussa vulgaris Nees, are used as folkmedicine. Ribes takare D. Don belongs to the genus Ribes. The three plants have notbeen chemically studied in detail. Chemical and bioactive study of three plants led tothe isolation of 48 compounds by chromatography. Their structures were elucidatedon the basis of spectroscopic evidence or comparison with authentic samples. Amongthe 48 componds isolated one protoberberine alkaloid and three biphenyls are newones. Cytotoxic and α-glucosidase inhibitory compounds had been found.1. Twelve compounds were isolated from the 95% ethanol extract of the aerial partof H. latifolia Wall. They were characterized as fellow: eleutheroside K (1),hederagenin-3-O- α-L-rhamnopyranosyl-(1→2)- α-L-arabinopyranoside (2),2-naphthyl acetic acid (3),3-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-α-L-arabinopyranosyl oleanolic acid 28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (4), 3-O- α-L-rhamnopyranosyl-(1→2)-O- β- D-glucopyranosyl-(1→2)- α-L-arabinopyranosyl oleanolic acid (5),3-O-( β-D-glucopyranosiduronic acid)-oleanolic acid-28-O- β-D-glucopyranoside (6),lup-20(29)-en-3-one (7), lupeol (8), β-sitosterol (9), oleanolic acid (10), ursolicacid (11), and β-daucosterol (12). Compound 1 showed moderate cytotoxicity againstLu-06 (GI50, 0.77 µg/mL), N-04 (GI50, 1.26 µg/mL) and Bre0-4 (GI50=1.55 µg/mL)and compound 2 showed moderate cytotoxicity against N-04 (GI50=2.44 µg/mL).2. A new protoberberine alkaloid, 13-hydroxyl gusanlung A (25), was isolated fromthe aerial part of Gendarussa vulgaris Nees, together with β-sitosterol (9), oleanolicacid (10), β-daucosterol (12), glycerol monopalmitate (13), palmific acid (14),albendazole (15), albendazole sulphone (16), albendazole sufloxide (17), aurantiamideacetate (18), kumatakenin (19), genkwanin (20), (-)-syringaresinol (21), gusanlung B(22), eupteleasaponinsⅤ acetate (23), gusanlung A (24), eleutheroside E (26),bergenin (27) and caffeic acid (28). Compound 25 showed cytotoxicity against HepG2 cells (GI50, 2.08 µg/mL).3. Phytochemical study of the Ribes takare D. Don led to the isolation of three newbiphenyls, 4,7,8-trimethoxy-2,3-methylenedioxydibenzofuran (30), 3', 5-dimethoxy-3,4-methylenedioxybiphenyl (31) and 7-hydroxy-4,8-dimethoxy-2,3-methylenedioxydibenzofuran (35), along with nineteenknown compounds, β-sitosterol (9), β-daucosterol (12), O-acetyloleanolic aldehyde(29), betulin (32), 6,7-dimethoxy-1-methyl-3,4-dihydroquinolin-2-one (33),3'-hydroxy-5-methoxy-3, 4-methylenedioxybiphenyl (34), betulinic aldehyde (36),gallic acid (37), stigmast-4-en-6β-ol-3-one (38), 5α, 8α-epidioxy-(22E, 24R)-ergosta-6,22-dien-3β-ol (39), verrucofortine (40), 6-methoxycalpogonium isoflavone A (41),2-hydroxybenzophenone (42), betulinic acid (43), 3,5-dimethoxygallic acid-4-O- β-D-glucopryranoside (44), apigenin (45), acacetin (46), salicylic acid (47) andapigenin-5-O- β-D-glucopryranoside (48). α-Glucosidase inhibitory rates ofcompound 30 and 35 were respectively 10.2% and 17.2% at a concentration of 1.00 mg/mL).4. Pharmacological activities of protoberberines were summarized.