925 resultados para 5-methoxy-3,4-dehydroxanthomegnin


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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.

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Abstract is not available.

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A new strategy for the total synthesis of methyl 8-methoxy-2,2-dimethyl-7-oxo-1,2,3,5,6,7-hexahydro-s-indacene-4-carboxylate 4, a key intermediate in the synthesis of illudalanes, is reported. The key step in this strategy is a new method of preparation of indanones from tetralones. Thus, the furfurylidene derivative of 6-methoxy-3,4-dihydronaphthalen-1-(2H)-one is oxidised to the dicarboxylic acid 9a which is cyclodehydrated to methyl 7-methoxy-1-oxoindan-4-carboxylate 10. Similar reactions on the tetrahydronaphthalenone 25, obtained from 6-methoxy-1,2,3,4-tetrahydronaphthalene-7-carbaldehyde 11 by sequential transformations including a regiospecific benzylic oxidation resulted in the hexahydro-s-indacenone 4, thus completing a formal synthesis of illudinine 1.

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A new generation of water soluble tetrazolium salts have recently become available and in this study we compared a colorimetric assay developed using one of these salts, 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2, 4-disulfophenyl)-2H-tetrazolium, monosodium salt (WST-8), with a previously developed 2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide(XTT) colorimetric assay to determine which agent is most suitable for use as a colorimetric indicator in susceptibility testing. The MICs of 6 antibiotics were determined for 33 staphylococci using both colorimetric assays and compared with those obtained using the British Society for Antimicrobial Chemotherapy reference broth microdilution method. Absolute categorical agreement between the reference and test methods ranged from 79% (cefuroxime) to 100% (vancomycin) for both assays. No minor or major errors occurred using either assay with very major errors ranging from zero (vancomycin) to seven (cefuroxime). Analysis of the distribution of differences in the 1092 dilution MIC results revealed overall agreement, within the accuracy limits of the standard test ( 1 1092 dilution), using the XTT and WST-8 assays of 98% and 88%, respectively. Further studies on 31 ESBL-producing isolates were performed using the XTT method with absolute categorical agreement ranging from 87% (nitrofurantoin) to 100% (ofloxacin and meropenem). No errors were noted for either ofloxacin or meropenem with overall agreement of 91%. The data suggests that XTT is more reliable and accurate than WST-8 for use in a rapid antimicrobial susceptibility test. (c) 2007 Elsevier B.V. All rights reserved.

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A new generation of water soluble tetrazolium salts have recently become available and in this study we compared a colorimetric assay developed using one of these salts, 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2, 4-disulfophenyl)-2H-tetrazolium, monosodium salt (WST-8), with a previously developed 2,3-bis [2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT) colorimetric assay to determine which agent is most suitable for use as a colorimetric indicator in susceptibility testing. The MICs of 6 antibiotics were determined for 33 staphylococci using both colorimetric assays and compared with those obtained using the British Society for Antimicrobial Chemotherapy reference broth microdilution method. Absolute categorical agreement between the reference and test methods ranged from 79% (cefuroxime) to 100% (vancomycin) for both assays. No minor or major errors occurred using either assay with very major errors ranging from zero (vancomycin) to seven (cefuroxime). Analysis of the distribution of differences in the log2 dilution MIC results revealed overall agreement, within the accuracy limits of the standard test (± 1 log2 dilution), using the XTT and WST-8 assays of 98% and 88%, respectively. Further studies on 31 ESBL-producing isolates were performed using the XTT method with absolute categorical agreement ranging from 87% (nitrofurantoin) to 100% (ofloxacin and meropenem). No errors were noted for either ofloxacin or meropenem with overall agreement of 91%. The data suggests that XTT is more reliable and accurate than WST-8 for use in a rapid antimicrobial susceptibility test.

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The structures of the anhydrous 1:1 proton-transfer compounds of isonipecotamide (4-carbamoylpiperidine) with picric acid and 3,5-dinitrosalicylic acid, namely 4-carbamoylpiperidinium 2,4,6-trinitrophenolate, C6H13N2O8+ C6H2N3O7- (I) and 4-carbamoylpiperidinium 2-carboxy-4,6-dinitrophenolate, C6H13N2O8+ C7H3N2O7-: two forms, the monoclinic alpha-polymorph (II) and the triclinic beta-polymorph (III) have been determined at 200 K. All compounds form hydrogen-bonded structures, one-dimensional in (II), two-dimensional in (I) and three-dimensional in (III). In (I), the cations form centrosymmetric cyclic head-to-tail hydrogen-bonded homodimers [graph set R2/2(14)] through lateral duplex piperidinium N---H...O(amide) interactions. These dimers are extended into a two-dimensional network structure through further interactions with anion phenolate-O and nitro-O acceptors, including a direct symmetric piperidinium N-H...O(phenol),O(nitro) cation--anion association [graph set R2/1(6)]. The monoclinic polymorph (II) has a similar R2/1(6) cation-anion hydrogen-bonding interaction to (I) but with an additional conjoint symmetrical R1/2(4) interaction as well as head-to-tail piperidinium N-H...O(amide) O hydrogen bonds and amide N-H...O(carboxyl) hydrogen bonds, give a network structure which include large R3/4(20) rings. The hydrogen bonding in the triclinic polymorph (III) is markedly different from that of monoclinic (II). The asymmetric unit contains two independent cation-anion pairs which associate through cyclic piperidinium N-H...O,O'(carboxyl) interactions [graph set R2/1(4)]. The cations also show the zig-zag head-to-tail piperidinium N-H...O(amide) hydrogen-bonded chain substructures found in (II) but in addition feature amide N-H...O(nitro) and O(phenolate) and amide N-H...O(nitro) associations. As well there is a centrosymmetric double-amide N-H...O(carboxyl) bridged bis(cation-anion) ring system [graph set R2/4(8)] in the three-dimensional framework. The structures reported here demonstrate the utility of the isonipecotamide cation as a synthon with previously unrecognized potential for structure assembly applications. Furthermore, the structures of the two polymorphic 3,5-dinitrosalicylic acid salts show an unusual dissimilarity in hydrogen-bonding characteristics, considering that both were obtained from identical solvent systems.

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The structures of the anhydrous products from the interaction of 2-amino-5-(4-bromophenyl)-1,3,4-thiadiazole with (2-naphthoxy)acetic acid, the 1:1 adduct C8H6BrN3S . C12H10O3 (I) and 3,5-dinitrobenzoic acid, the salt C8H7BrN3S+ C7H3N2O6- (II) have been determined. In the adduct (I), a heterodimer is formed through a cyclic hydrogen-bonding motif [graph set R2/2(8)], involving carboxylic acid O-H...N(hetero)and amine N-H...O(carboxyl) interactions. The heterodimers are essentially planar with a thiadiazole to naphthyl ring dihedral angle of 15.9(2)deg. and the intramolecular thiadiazole to phenyl ring angle of 4.7(2)deg. An amine N-H...N(hetero) hydrogen bond between the heterodimers generates a one-dimensional chain structure extending down [001]. Also present are weak benzene-benzene and naphthalene-naphthalene pi-pi stacking interactions down the b axis [minimum ring centroid separation, 3.936(3) Ang.]. With the salt (II), the cation-anion association is also through a cyclic R2/2(8) motif but involving duplex N-H...O(carboxyl) hydrogen bonds, giving a heterodimer which is close to planar [dihedral angles between the thiadiazole ring and the two benzene rings, 5.00(16)deg. (intra) and 7.23(15)deg. (inter)]. A secondary centrosymmetric cyclic N-H...O(carboxyl) hydrogen-bonding association involving the second amino H-atom generates a heterotetramer. Also present in the crystal are weak pi-pi i-\p interactions between thiadiazolium rings [minimum ring centroid separation, 3.936(3)Ang.], as well as a short Br...O(nitro) interaction [3.314(4)Ang.]. The two structures reported here now provide a total of three crystallographically characterized examples of co-crystalline products from the interaction of 2-amino-5-(4-bromophenyl)-1,3,4-thiadiazole with carboxylic acids, of which only one involves proton-transfer.

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The structures of the ammonium salts of 3,5-dinitrobenzoic acid, NH4+ C7H3N2O6- (I), 4-nitrobenzoic acid, NH4+ C7H4N2O4- . 2H2O (II) and 2,4-dichlorobenzoic acid, NH4+ C7H3Cl2O2- . 0.5H2O (III), have been determined and their hydrogen-bonded structures are described. All salts form hydrogen-bonded polymeric structures, three-dimensional in (I) and two-dimensional in (II) and (III). With (I), a primary cation-anion cyclic association is formed [graph set R3/4(10)] through N-H...O hydrogen bonds, involving a carboxyl O,O' group on one side and a single carboxyl O-atom on the other. Structure extension involves both N-H...O hydrogen bonds to both carboxyl and nitro O-atom acceptors. With structure (II), the primary inter-species interactions and structure extension into layers lying parallel to (0 0 1) are through conjoined cyclic hydrogen-bonding motifs: R3/4(10) [one cation, a carboxyl (O,O') group and two water molecules] and centrosymmetric R2/4(8) [two cations and two water molecules]. The structure of (III) also has conjoined R3/4(10) and centrosymmetric R2/4(8) motifs in the layered structure but these differ in that he first involves one cation, a carboxyl (O,O') as well as a carboxyl (O) group and one water molecule, the second, two cations and two carboxyl O-groups. The layers lie parallel to (1 0 0). The structures of the salt hydrates (II) and (III) reported in this work, giving two-dimensional layered arrays through conjoined hydrogen-bonded nets provide further illustrations of a previously indicated trend among ammonium salts of carboxylic acids, but the anhydrous three-dimensional structure of (I) is inconsistent.

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A new diketopyrrolopyrrole (DPP)-containing donor-acceptor polymer, poly(2,5-bis(2-octyldodecyl)-3,6-di(furan-2-yl)-2,5-dihydro-pyrrolo[3,4-c] pyrrole-1,4-dione-co-thieno[3,2-b]thiophene) (PDBF-co-TT), is synthesized and studied as a semiconductor in organic thin film transistors (OTFTs) and organic photovoltaics (OPVs). High hole mobility of up to 0.53 cm 2 V -1 s -1 in bottom-gate, top-contact OTFT devices is achieved owing to the ordered polymer chain packing and favoured chain orientation, strong intermolecular interactions, as well as uniform film morphology of PDBF-co-TT. The optimum band gap of 1.39 eV and high hole mobility make this polymer a promising donor semiconductor for the solar cell application. When paired with a fullerene acceptor, PC 71BM, the resulting OPV devices show a high power conversion efficiency of up to 4.38% under simulated standard AM1.5 solar illumination.

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Solution processable diketopyrrolopyrrole (DPP)-bithiophene polymers (PDBT) with long branched alkyl side chains on the DPP unit are synthesized. These polymers have favourable highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels for the injection and transport of both holes and electrons. Organic thin film transistors (OTFTs) using these polymers as semiconductors and gold as source/drain electrodes show typical ambipolar characteristics with very well balanced high hole and electron mobilities (μ h = 0.024 cm 2 V -1 s -1 and μ e = 0.056 cm 2 V -1 s -1). These simple and high-performing polymers are promising materials for ambipolar organic thin film transistors for low-cost CMOS-like logic circuits.