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1.
Arch Microbiol ; 206(4): 183, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502272

RESUMO

This study aimed to reveal that the effect of biosurfactant on the dispersion and degradation of crude oil. Whole genome analysis showed that Pseudomonas aeruginosa GB-3 contained abundant genes involved in biosurfactant synthesis and metabolic processes and had the potential to degrade oil. The biosurfactant produced by strain GB-3 was screened by various methods. The results showed that the surface tension reduction activity was 28.6 mN·m-1 and emulsification stability was exhibited at different pH, salinity and temperature. The biosurfactant was identified as rhamnolipid by LC-MS and FTIR. The fermentation conditions of strain GB-3 were optimized by response surface methodology, finally the optimal system (carbon source: glucose, nitrogen source: ammonium sulfate, C/N ratio:16:1, pH: 7, temperature: 30-35 °C) was determined. Compared with the initial fermentation, the yield of biosurfactant increased by 4.4 times after optimization. In addition, rhamnolipid biosurfactant as a dispersant could make the dispersion of crude oil reach 38% within seven days, which enhanced the bioavailability of crude oil. As a biostimulant, it could also improve the activity of indigenous microorganism and increase the degradation rate of crude oil by 10-15%. This study suggested that rhamnolipid biosurfactant had application prospect in bioremediation of marine oil-spill.


Assuntos
Petróleo , Pseudomonas aeruginosa , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Tensoativos/química , Glicolipídeos/química , Petróleo/metabolismo
2.
Biodegradation ; 33(5): 461-476, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35729449

RESUMO

In order to enhance the degradation effect of microorganisms on crude oil in the existence of chlorophenol compounds, oil-degrading bacteria C4 (Alcaligenes faecails), C5 (Bacillus sp.) and 2,4-dichlorophenol (2,4-DCP) degrading bacteria L3 (Bacillus marisflavi), L4 (Bacillus aquimaris) were isolated to construct a highly efficient consortium named (C4C5 + L3L4). When the compound bacteria agent combination by VC4: VC5: VL3: VL4 = 1:2:2:1, the crude oil degradation efficiency of 7 days was stable at 50.63% ~ 55.43% under different conditions. Degradation mechanism was analyzed by FTIR, GC-MS and IC technology and the following conclusions showed that in the system of adding consortium (C4C5 + L3L4), the heavy components were converted into saturated and unsaturated components. The bacterial consortium could first degrade medium and long chain alkanes into short chain hydrocarbons and then further degrade. And the dechlorination efficiency of 2,4-DCP in the degradation system reached 73.83%. The results suggested that the potential applicability and effectiveness of the selected bacteria consortium for the remediation of oil-contaminated water or soil with the existence of chlorophenol compound.


Assuntos
Clorofenóis , Petróleo , Poluentes do Solo , Bactérias/metabolismo , Biodegradação Ambiental , Clorofenóis/metabolismo , Hidrocarbonetos/metabolismo , Petróleo/análise , Microbiologia do Solo , Poluentes do Solo/metabolismo
3.
Neuroimage ; 200: 644-658, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31252056

RESUMO

Type 2 diabetes mellitus (T2DM) is a significant risk factor for mild cognitive impairment (MCI) and the acceleration of MCI to dementia. The high glucose level induce disturbance of neurovascular (NV) coupling is suggested to be one potential mechanism, however, the neuroimaging evidence is still lacking. To assess the NV decoupling pattern in early diabetic status, 33 T2DM without MCI patients and 33 healthy control subjects were prospectively enrolled. Then, they underwent resting state functional MRI and arterial spin labeling imaging to explore the hub-based networks and to estimate the coupling of voxel-wise cerebral blood flow (CBF)-degree centrality (DC), CBF-mean amplitude of low-frequency fluctuation (mALFF) and CBF- mean regional homogeneity (mReHo). We further evaluated the relationship between NV coupling pattern and cognitive performance (false discovery rate corrected). T2DM without MCI patients displayed significant decrease in the absolute CBF-mALFF, CBF-mReHo coupling of CBFnetwork and in the CBF-DC coupling of DCnetwork. Besides, networks which involved CBF and DC hubs mainly located in the default mode network (DMN). Furthermore, less severe disease and better cognitive performance in T2DM patients were significantly correlated with higher coupling of CBF-DC, CBF-mALFF or CBF-mReHo, especially for the cognitive dimensions of general function and executive function. Thus, coupling of CBF-DC, CBF-mALFF and CBF-mReHo may serve as promising indicators to reflect NV coupling state and to explain the T2DM related early cognitive impairment.


Assuntos
Encéfalo/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Neuroimagem Funcional/métodos , Rede Nervosa/fisiopatologia , Acoplamento Neurovascular/fisiologia , Biomarcadores , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem
4.
Pharmacol Res ; 146: 104310, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31229563

RESUMO

Acacetin, a natural flavonoid, possesses broad spectrum of pharmacological and biochemical activities, such as neuroprotection, antinociception and inhibition of monoamine oxidase. The current work aimed to investigate the antidepressant-like activity of acacetin in mice and explore the underlying mechanism(s). Chronic, but not acute, acacetin treatment (5, 15 or 45 mg/kg, p.o., once per day for three weeks) exerted in mice dose-dependently antidepressant-like activity, assessed by forced swim test (FST) and tail suspension test (TST). Although acacetin-treated mice showed normal circadian hypothalamo-pituitary-adrenal (HPA) axis activity, their endocrine responsivity to both acute restraint stress and intracerebroventricular injection of corticotropin-releasing factor (CRF) was buffered. The acacetin-triggered antidepressant-like activities are serotonergically dependent, since its impacts on behavior and stress responsivity were totally abolished by chemical depletion of brain serotonin by PCPA. Consistently, acacetin-treated mice showed escalated levels of brain monoamines especially serotonin and depressed activity of monoamine oxidase. Moreover, the acacetin-evoked anti-depression was preferentially counteracted by co-administration of 5-HT1A receptor antagonist WAY-100635, but potentiated by 5-HT1A receptor agonist 8-OH-DPAT and sub-effective dose of serotonergic antidepressant fluoxetine, suggesting a pivotal engagement of 5-HT1A related serotonergic system. In vitro, acacetin (1-100 nM) increased the Emax of 8-OH-DPAT. Collectively, these findings confirm that chronic acatetin administration to mice engenders antidepressant-like efficacy on both behavior and stress axis responsivity, with serotonergic system that preferentially couples with 5-HT1A receptors being critically involved.


Assuntos
Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Flavonas/farmacologia , Serotonina/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Animais , Depressão/metabolismo , Fluoxetina/farmacologia , Elevação dos Membros Posteriores/fisiologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Piperazinas/farmacologia , Piridinas/farmacologia , Receptor 5-HT1A de Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Natação/fisiologia
5.
Acta Biochim Biophys Sin (Shanghai) ; 48(3): 238-45, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26883800

RESUMO

Kaempferol is a flavonoid that has been reported to exhibit antitumor activity in various malignant tumors. However, the role of kaempferol on cholangiocarcinoma (CCA) is largely unknown. In this article, we found that kaempferol inhibited proliferation, reduced colony formation ability, and induced apoptosis in HCCC9810 and QBC939 cells in vitro. Results from transwell assay and wound-healing assay demonstrated that kaempferol significantly suppressed the migration and invasion abilities of HCCC9810 and QBC939 cells in vitro. Kaempferol was found to decrease the expression of Bcl-2 and increase the expressions of Bax, Fas, cleaved-caspase 3, cleaved-caspase 8, cleaved-caspase 9, and cleaved-PARP. In addition, kaempferol also downregulated the levels of phosphorylated AKT, TIMP2, and MMP2. In vivo, it was found that the volume of subcutaneous xenograft (0.15 cm(3)) in the kaempferol-treated group was smaller than that (0.6 cm(3)) in the control group. Kaempferol also suppressed the number and volume of metastasis foci in the lung metastasis model, with no marked effects on body weight of mice. Immunohistochemistry assay showed that the number of Ki-67-positive cells was lower in the kaempferol-treated group than that in the control group. We further confirmed that the changes of apoptosis- and invasion-related proteins after kaempferol treatment in vivo were similar to the results in vitro. These data suggest that kaempferol may be a promising candidate agent for the treatment of CCA.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Proliferação de Células/efeitos dos fármacos , Colangiocarcinoma/patologia , Quempferóis/farmacologia , Metástase Neoplásica/prevenção & controle , Animais , Linhagem Celular Tumoral , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica/prevenção & controle
6.
Luminescence ; 28(3): 419-26, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22826126

RESUMO

Three novel p-hydroxybenzoic acid derivatives (HSOP, HSOX, HSCP) were synthesized from p-hydroxybenzoic acid and sulfonamides (sulfamonomethoxine sodium, sulfamethoxazole and sulfachloropyridazine sodium) and characterized by elemental analysis, HNMR and MS. Interactions between derivatives and bovine serum albumin (BSA) were studied by fluorescence quenching spectra, UV-vis absorption spectra and time-resolved fluorescence spectra. Based on fluorescence quenching calculation and Förster's non-radioactive energy transfer theory, the values of the binding constants, basic thermodynamic parameters and binding distances were obtained. Experimental results indicated that the three derivatives had a strong ability to quench fluorescence from BSA and that the binding reactions of the derivatives with BSA were a static quenching process. Thermodynamic parameters showed that binding reactions were spontaneous and exothermic and hydrogen bond and van der Waals force were predominant intermolecular forces between the derivatives and BSA. Synchronous fluorescence spectra suggested that HSOX and HSCP had little effect on the microenvironment and conformation of BSA in the binding reactions but the microenvironments around tyrosine residues were disturbed and polarity around tyrosine residues increased in the presence of HSOP.


Assuntos
Hidroxibenzoatos/química , Soroalbumina Bovina/química , Animais , Bovinos , Fluorescência , Ligação Proteica , Termodinâmica
7.
Environ Sci Pollut Res Int ; 30(13): 35670-35682, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36538219

RESUMO

The groundwater polluted by an agricultural hormone site was taken as the research object, and a total of 7 groundwater samples were collected at different locations in the plant. The main pollutants in the research area were determined to be extractable petroleum hydrocarbons (C10-C40); 1,2-dichloroethane; 1,1,2-trichloroethane; carbon tetrachloride; vinyl chloride, and chloroform; the maximum content of these pollutants can reach 271 mg/L, 1.68 × 107 µg/L, 1.56 × 104 µg/L, 9.53 × 104 µg/L, 6.58 × 104 µg/L, and 4.81 × 104 µg/L, respectively. Aiming at the problems of groundwater pollution in this area, two sets of oxidation experiments have been carried out. The addition of NaHSO3 modified Fenton oxidation system was used in this contaminated water, which enhanced (2.2 ~ 46.7%) chemical oxygen demand (COD) removal rate. The highest removal rate of extractable petroleum hydrocarbons (C10-C40) can reach 99%. And the degradation rate of chlorinated hydrocarbon pollutants can reach 99% to 100%, which almost achieved the purpose of complete removal. In the NaHSO3 modified Fenton oxidation system, the addition of NaHSO3 accelerates the cycle of Fe3+/Fe2+ and ensures the continuous existence of Fe2+ in the reaction system, thereby producing more ·OH and further oxidizing and degrading organic pollutants. Our work has provided important insights for this economically important treatment of this type water body and laid the foundation for the engineering of this method.


Assuntos
Poluentes Ambientais , Água Subterrânea , Petróleo , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Peróxido de Hidrogênio/química , Oxirredução , Água Subterrânea/química , Poluição da Água , Hidrocarbonetos/química , Água
8.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): o379, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22347002

RESUMO

The title compound, C(19)H(19)N(3)O(7)S·CH(3)OH, was synthesized from syringic acid and sulfamethoxazole. The benzene rings make a dihedral angle of 41.8 (1)° and the isoxazole ring is twisted by 74.3 (1)° from the central benzene ring. The crystal packing features O-H⋯O and O-H⋯N hydrogen bonds in which the hy-droxy groups from the main mol-ecule and methanol solvent mol-ecules serve as donor groups.

9.
Dalton Trans ; 51(47): 18317-18328, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36416140

RESUMO

Traditional approaches to synthesizing bismuth nanoparticle decorated carbon nitride (C3N4) materials suffer from the complex synthesis process and the addition of a surfactant, which is not conducive to environmental protection. To address these problems, we adopted a simple and green flux-assisted approach for the first time to fabricate metallic bismuth nanoparticle decorated C3N4 (BiCCN). Electron microscopy results suggested that bismuth vanadate was converted into small bismuth nanoparticles via the flux-assisted approach. Highly dispersed Bi nanoparticles dramatically intensify light absorption, facilitate spatial charge separation as electron acceptors, shorten the charge diffusion length, and reserve more active sites for generating reactive species via surface photo-redox reactions. Consequently, the derived optimized photocatalyst BiCCN-15 rendered around 26 times higher photocatalytic degradation efficiency toward an endocrine disrupting compound (bisphenol A) than C3N4. This work provides a novel approach for developing non-precious metal decorated photocatalytic materials for sustainable water decontamination.


Assuntos
Bismuto
10.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 2): o354, 2011 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21523034

RESUMO

The benzene ring in the title compound, C(10)H(10)O(4), makes an angle of 4.4 (1)° with the C-C-C-O linker. The hy-droxy groups are involved in both intra- and inter-molecular O-H⋯O hydrogen bonds. The crystal packing is stabilized by O-H⋯O hydrogen-bonding inter-actions. The mol-ecules of the caffeic acid ester form a dimeric structure in a head-to-head manner along the a axis through O-H⋯O hydrogen bonds. The dimers inter-act with one another through O-H⋯O hydrogen bonds, forming supermolecular chains. These chains are further extended through C-H⋯O hydrogen bonds as well as van der Waals inter-actions into the final three-dimensional architecture.

11.
Br J Pharmacol ; 178(19): 4005-4025, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34030210

RESUMO

BACKGROUND AND PURPOSE: Neuropathic pain places a devastating health burden, with very few effective therapies. We investigated the potential antiallodynic and antihyperalgesic effects of apigenin, a natural flavonoid with momoamine oxidase (MAO) inhibitory activity, against neuropathic pain and investigated the mechanism(s). EXPERIMENTAL APPROACH: The neuropathic pain model was produced by chronic constriction injury of sciatic nerves in male C57BL/6J mice, with pain-related behaviours being assayed by von Frey test and Hargreaves test. In this model the role of 5-HT and 5-HT1A receptor-related mechanisms were investigated in vivo/in vitro. KEY RESULTS: Apigenin repeated treatment (p.o., once per day for 2 weeks), in a dose-related manner (3, 10 and 30 mg·kg-1 ), ameliorated the allodynia and hyperalgesia in chronic nerve constriction injury in mice. These effects seem dependent on neuronal 5-hydroxytryptamine, because (i) the antihyperalgesia and antiallodynia were attenuated by depletion of 5-HT with p-chlorophenylalanine and potentiated by 5-hydroxytryptophan and (ii), apigenin-treated chronic constriction injury mice caused an increased level of spinal 5-HT, associated with diminished MAO activity. In vivo administration, spinally or systematically, of the 5-HT1A antagonist WAY-100635 inhibited the apigenin-induced antiallodynia and antihyperalgesia. In vitro, apigenin acted as a positive allosteric modulator to increase the efficacy (stimulation of [35 S]GTPγS binding) of the 5-HT1A agonist 8-OH-DPAT. Apigenin attenuated neuronal changes caused by chronic constriction of the sciatic nerve in mice, without causing a hypertensive crisis. CONCLUSION AND IMPLICATIONS: Apigenin antiallodynic and antihyperalgesic actions against neuropathic pain crucially involve spinal 5-HT1A receptors and indicate it could be used to treat neuropathic pain.


Assuntos
Mononeuropatias , Receptor 5-HT1A de Serotonina , Animais , Apigenina/farmacologia , Modelos Animais de Doenças , Hiperalgesia/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL
12.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 2): m113, 2010 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-21579602

RESUMO

In the title compound, [Na(H(2)O)(4)](C(15)H(9)N(2)O(2)), the Na(+) ion is coordinated by six water mol-ecules in an octa-hedral geometry. The NaO(6) octa-hedra are connected by sharing edges, forming a cationic chain along the b-axis direction. O-H⋯O and O-H⋯N hydrogen bonds link the chains and the 2-(2-pyrid-yl)quinoline-4-carboxyl-ate anions into a two-dimensional network parallel to (100).

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(3): 682-5, 2009 Mar.
Artigo em Zh | MEDLINE | ID: mdl-19455799

RESUMO

An infrared spectroscopy method for rapid quantitative determination of the degree of esterification (DE) of pectic polysaccharides was developed. Taking pectic polysaccharides from angelica sinensis as samples, the calibration curve was established between DE and the ratio of A1 730/(A1 730 + A1 630). The square of the linear correlation coefficient was 0.822, indicating a good linear relationship between the DE and the absorbent area at 1 730 and 1 630 cm(-1). Using this method, the DE of pectic polysaccharides from angelica sinensis was determined to be between 42.36% and 54.06% for crude and purified samples respectively. The relationship between infrared spectroscopy data and titrimetrically determined DE values was investigated, indicating an excellent reproducibility. This method is characterized by less sample, simple manipulation, higher sensibility, and speedy analysis compared to chemical method and other instrumentations. FTIR shows a good feasibility and can be a rapid, alternative method to titrimetric analysis for DE determination.


Assuntos
Angelica sinensis/química , Pectinas/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Absorção , Calibragem , Esterificação
14.
World J Gastroenterol ; 14(30): 4810-5, 2008 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-18720545

RESUMO

AIM: To explore the effect of trichostatin A (TSA) on apoptosis and acetylated histone H3 levels in gastric cancer cell lines BGC-823 and SGC-7901. METHODS: The effect of TSA on growth inhibition and apoptosis was examined by MTT, fluorescence microscopy and PI single-labeled flow cytometry. The acetylated histone H3 level was detected by Western blot. RESULTS: TSA induced apoptosis in gastric cancer cell lines BGC-823 and SGC-7901 was in a dose and time-dependent manner. Apoptotic cells varied significantly between TSA treated groups (37.5 ng/mL 72 h for BGC-823 cell line and 75 ng/mL 72 h for SGC-7901 cell line) and control group (0.85+/-0.14 vs 1.14+/-0.07, P=0.02; 0.94+/-0.07 vs 1.15+/-0.06, P=0.02). Morphologic changes of apoptosis, including nuclear chromatin condensation and fluorescence strength, were observed under fluorescence microscopy. TSA treatment in BGC-823 and SGC-7901 cell lines obviously induced cell apoptosis, which was demonstrated by the increased percentage of sub-G1 phase cells, the reduction of G1-phase cells and the increase of apoptosis rates in flow cytometric analysis. The result of Western blot showed that the expression of acetylated histone H3 increased in BGC-823 and SGC-7901 TSA treatment groups as compared with the control group. CONCLUSION: TSA can induce cell apoptosis in BGC-823 and SGC-7901 cell lines. The expression of acetylated histone H3 might be correlated with apoptosis.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inibidores de Histona Desacetilases , Histonas/metabolismo , Ácidos Hidroxâmicos/farmacologia , Neoplasias Gástricas/patologia , Acetilação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Histona Desacetilases/metabolismo , Humanos , Neoplasias Gástricas/enzimologia , Fatores de Tempo
15.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): m407, 2008 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-21201354

RESUMO

In the title complex, [Gd(C(11)H(10)N(3)O(2))(3)]·0.5CH(4)O·2.5H(2)O, the Gd atom is coordinated by six N atoms and three O atoms derived from three tridentate monoanionic 6-(3,5-dimethyl-1H-pyrazol-1-yl)picolinate ligands. The mol-ecules are linked together via hydrogen bonds involving the solvent water and methanol mol-ecules.

16.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): m410, 2008 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-21201356

RESUMO

In the title complex, [La(C(11)H(10)N(3)O(2))(2)(NO(3))(H(2)O)(2)]·H(2)O, the La atom is coordinated by four N atoms and six O atoms derived from two 6-(3,5-dimethyl-1H-pyrazol-1-yl)picolinate ligands, one nitrate anion and two water mol-ecules. The mol-ecules are linked together via hydrogen bonds involving the water mol-ecules, forming a three-dimensional network.

17.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): m408-9, 2008 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-21201355

RESUMO

In the title complex, [Dy(C(11)H(10)N(3)O(2))(3)(H(2)O)]·3H(2)O, the Dy(III) atom is coordinated by four N atoms and four O atoms derived from three tridentate deprotonated 6-(3,5-dimethyl-1H-pyrazol-1-yl)picolinate ligands and one water mol-ecule. The complex and solvent water mol-ecules are linked together via O-H⋯O, O-H⋯N, C-H⋯O and C-H⋯π hydrogen-bonding inter-actions, forming a three-dimensional network structure.

18.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): m434, 2008 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-21201375

RESUMO

In the title complex, [Cd(C(11)H(10)N(3)O(2))(2)]·1.75H(2)O, the Cd atom is coordinated by four N atoms and two O atoms from two tridentate 6-(3,5-dimethyl-1H-pyrazol-1-yl)picolinate ligands in a distorted cis-N(4)O(2) octa-hedral geometry. Three water mol-ecules, with occupancies of 1.0, 0.5 and 0.25, complete the asymmetric unit. The components of the crystal structure are linked via hydrogen bonds, forming a three-dimensional network.

19.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 5): o871, 2008 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-21202357

RESUMO

In the title compound, C(10)H(4)Cl(4)N(4)O, the pyridine and pyrimidine rings are nearly perpendicular to each other, the dihedral angle between them being 86.60 (10)°. In the crystal structure, the N and O atoms in the amide group are involved in inter-molecular hydrogen bonds, forming a one-dimensional chain along the c axis.

20.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 5): o890, 2008 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-21202373

RESUMO

The title compound, C(30)H(50)O(3), which was isolated from a marine endophytic fungus, is a new friedelan derivative. The mol-ecule contains five six-membered rings, which exhibit boat (ring A), distorted boat (ring B) and chair (rings C-E) conformations. The crystal structure is stabilized by inter-molecular O-H⋯O hydrogen bonds, which link neighbouring mol-ecules into 12-membered rings.

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