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1.
Proc Natl Acad Sci U S A ; 120(46): e2312907120, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37922331

RESUMEN

Metallosurfactants, defined here as hydrophobic metal-containing groups embedded in hydrophilic units when dispersed in water, emanate in the formation of metallomicelles. This approach continues to attract great interest for its ability to serve as micellar catalysts for various metal-mediated chemical transformations in water. Indeed, relevant to green chemistry, micellar catalysis plays a preeminent function as a replacement for organic solvents in a variety of chemical reactions. There are several methods for the interaction of metal complexes (catalysts or catalyst precursors) and surfactants for producing micellar aggregates. A very effective manner for achieving this involves the direct bonding of the metal center to the amphiphilic polymeric materials. Herein, we describe the synthesis of a metallosurfactant containing a palladium complex covalently incorporated into a CO2-based triblock polycarbonate derived using a dicarboxylic acid chain-transfer agent. This amphiphilic polycarbonate was shown to self-assemble in water to provide uniform and spherical micelles, where the catalytic metal center is located in the hydrophobic portion of the micelle. The resulting metallosurfactant was demonstrated to effectively catalyze carbon-carbon coupling reactions at very low catalyst loadings.

2.
Medicine (Baltimore) ; 102(47): e36256, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38013340

RESUMEN

Numerous research studies have investigated the relationship between ABO and Rhesus (Rh) blood groups and the risk of various cancers, yielding diverse findings. While these blood groups have been established as prognostic factors in some cancers, their relevance to colorectal cancer (CRC) remains uncertain. This research aims to determine the link between CRC and the ABO and Rh blood groups and explore any potential implications for disease survival. A hospital-based prospective observational study was conducted from March 2019 to March 2022 at the Sher-I-Kashmir Institute of Medical Sciences in Srinagar, India. A total of 246 patients with confirmed colorectal cancer were enrolled in the study. Our study observed that blood type B (33.74%) and Rh-positive (91.87%) blood types were the most prevalent, surpassing other blood groups. No statistically significant associations were identified between the blood groups and the studied xenobiotic-metabolizing enzyme gene variants. The study observed a heightened risk of CRC in patients with advanced cancer stages and lymphovascular invasion (P-value < .05). On follow-up, there were no statistically significant differences in 3-year survival rates observed between ABO and Rh blood groups. This study's findings suggest that ABO and Rh blood groups are not associated with the risk of CRC or overall survival among CRC patients. Further clinical studies are needed to establish the precise relationship between blood groups and CRC risks, as well as their implications for the prognosis of CRC patients.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Neoplasias Colorrectales , Humanos , Sistema del Grupo Sanguíneo Rh-Hr , Pronóstico , Estudios Prospectivos
3.
Angew Chem Int Ed Engl ; 62(48): e202307507, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37534963

RESUMEN

Aliphatic polycarbonates (aPCs) have become increasingly popular as functional materials due to their biocompatibility and capacity for on-demand degradation. Advances in polymerization techniques and the introduction of new functional monomers have expanded the library of aPCs available, offering a diverse range of chemical compositions and structures. To accommodate the emerging requirements of new applications in biomedical and energy-related fields, various manufacturing techniques have been adopted for processing aPC-based materials. However, a summary of these techniques has yet to be conducted. The aim of this paper is to enrich the toolbox available to researchers, enabling them to select the most suitable technique for their materials. In this paper, a concise review of the recent progress in processing techniques, including controlled self-assembly, electrospinning, additive manufacturing, and other techniques, is presented. We also highlight the specific challenges and opportunities for the sustainable growth of this research area and the successful integration of aPCs in industrial applications.

4.
Biomedicines ; 11(2)2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36831076

RESUMEN

BACKGROUND: Suppressor of fused (SuFu) is a tumor-suppressor gene that regulates hedgehog signaling. Its involvement in some malignancies is broadly accepted. However, its association with colorectal cancer (CRC) pathogenesis is not clear. Likewise, no study has clearly associated blood-based inflammatory biomarkers with cancer diagnosis/prognosis as yet. AIM: Our goal was to look at SuFu expression levels in CRC patients and its relationship with other clinicopathological factors. Additionally, we looked into the function of a few blood-based biomarkers in CRC and whether or not a combined strategy at the genetic and clinical levels can be applied in CRC. METHODS: The investigation included 98 histopathologically confirmed CRC samples and adjacent normal tissues (controls). A colonoscopy was followed by a targeted biopsy for each suspected colon cancer patient. A CT scan and MRI were also performed on every patient with rectal cancer. Real-time polymerase chain reaction and immunohistochemistry (IHC) were used for assessment. A Beckman Coulter DxH900 was used to examine blood parameters. A Beckman Coulter DxI800 was used to identify pretreatment carcinoma embryonic antigens (CEA) and carbohydrate antigens (CA 19-9) in CRC patients. RESULTS: The expression of SuFu was associated with gender, education, passive smoking, tumor grade, perineural invasion (PNI), lymph node metastasis (LNM), node status, stage, vital status, and recurrence (p < 0.05). In the combined analysis, the areas under the curve produced by the platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), and red cell distribution width (RDW) were the greatest (AUCRDW+PLR+NLR = 0.91, 95% CI: 0.86-0.93, p < 0.05). Furthermore, the most severe pathological features were linked to RDW, PLR, NLR, and HPR. SuFu expression, node status, LNM, PNI, and stage all had significant correlations with OS and DFS rates in IHC-based univariate survival analysis (p < 0.05). According to the Cox regression, CA-19.9 had a strong independent predictive link with 3-year DFS (p < 0.05). CONCLUSION: In CRC, SuFu was downregulated both transcriptionally and translationally, was primarily nucleo-cytoplasmic, and was expressed less in high-grade tumors. In addition, SuFu was linked to a poor overall and disease-free survival rate. It may be possible to use SuFu as a therapeutic target for CRC in the future. However, SuFu expression had no effect on RDW, PLR, NLR, or HPR serum levels.

5.
Clin Exp Med ; 23(6): 2385-2405, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36318377

RESUMEN

Forkhead Box M1 (FOXM1)-a key cell cycle regulator is a member of the Forkhead transcription factor family. It plays a key role in embryogenesis and cell proliferation and has been strongly linked to various solid tumors. We sought to understand the regulation of FOXM1 in colorectal cancer (CRC), as well as if and to what extent other clinicopathological characteristics are associated with FOXM1. The investigation comprised 98 CRC samples and normal tissues (controls). All colon cancer patients had a colonoscopy and targeted biopsy. All rectal cancer patients had a CT and MRI. Real-time PCR, Immunohistochemistry, and Western blotting were used to evaluate FOXM1 expression, and the findings were analyzed using SPSS (v.26). FOXM1 mRNA and protein expression were substantially upregulated in tumor tissues, with the majority of these proteins localized in nucleo-cytoplasm. Elevated protein levels of FOXM1 were strongly correlated with lower education level, larger tumor size, lymph node status, lymphovascular invasion (LVI), perineural invasion (PNI), lymph node metastasis (LNM), tumor invasion depth (subserosal and serosal invasion), late stage (III and IV), localization (nucleo-cytoplasmic), intensity (strong) and recurrence. Based on survival analysis, FOXM1 overexpression and nucleo-cytoplasmic localization were associated with shorter disease-free survival while stage and PNI were linked to poorer overall and disease-free survival. According to the results of the Cox regression analysis, stage and PNI were significant predictors of prognosis in CRC patients. FOXM1 expression was elevated in CRC and was linked to reduced disease-free survival. These findings support prior reports and hence FOXM1 can be an important prognostic marker for CRC and a promising therapeutic target. Additionally, we found a link between poor disease-free survival and FOXM1's nucleo-cytoplasmic localization. However, since the sample size of this study was small, further research is needed to validate our findings.


Asunto(s)
Neoplasias Colorrectales , Proteína Forkhead Box M1 , Humanos , Proteína Forkhead Box M1/genética , Factores de Transcripción Forkhead/genética , Pronóstico , Metástasis Linfática , Neoplasias Colorrectales/patología , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Línea Celular Tumoral
7.
RSC Adv ; 12(50): 32440-32447, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36425720

RESUMEN

Recent years have witnessed intensive research activity in exploring novel metal-free organocatalysts for catalyzing the coupling reactions of CO2 and epoxides to afford cyclic or polymeric carbonates. In this direction, herein we report a series of boron-phosphonium organocatalysts for catalyzing the coupling reactions of CO2 and epoxides. These organophosphonium catalysts were synthesized in high yields by following a two step protocol involving Menschutkin and hydroboration reactions in succession. The purity of these organocatalysts was confirmed by spectroscopic techniques like 1H, 13C and 31P NMR, and molecular structures were confirmed by single crystal X-ray diffraction studies. We have also demonstrated that these bifunctional organoboron-phosphonium catalysts are comparatively much less hygroscopic compared to the analogus ammonium catalysts. These phosphonium organocatalysts were shown to catalyze the copolymerization of CO2 and cyclohexene oxide or vinyl cyclohexene oxide to provide polycarbonates with >99% polymer selectivity and carbonate linkages. The coupling reactions of aliphatic epoxides such as PO, having lower energy barrier to cycloaddition formation compared to alicyclic epoxides, preferentially provided cyclic carbonates in good yields. It was demonstrated that these organoboron-phosphonium catalysts are sensitive to chain transfer agents like water, and hence are deactivated in its presence. This is opposite to what is observed for metal based catalysts for these transformations, where water serves as a precursor to the chain-transfer agent diols.

8.
Angew Chem Int Ed Engl ; 61(37): e202208355, 2022 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-35880834

RESUMEN

We report the facile synthesis and 3D printing of a series of triblock copolymers consisting of soft and hard blocks and demonstrate that alkene pendant groups of the hard block can be covalently modified. The polymers are prepared using a salenCo(III)TFA/PPNTFA binary catalyst system and 1,2-propanediol as a chain transfer agent, providing an efficient one-pot, two-step strategy to tailor polymer thermal and mechanical properties. Thixotropic inks suitable for direct ink write printing were formulated by dissolving the block copolymers in organic solvent and dispersing NaCl particles. After printing, porous structures were produced by removing solvent and NaCl with water to give printed structures with surfaces that could be modified via UV-initiated thiol-ene click reactions. Alternatively, a tetra-thiol could be incorporated into the ink and used for cross-linking to give objects with high solvent resistance and selective degradability.

9.
World J Gastroenterol ; 28(5): 547-569, 2022 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-35316957

RESUMEN

BACKGROUND: Connective tissue growth factor (CTGF) is a mediator of transforming growth factor-beta signaling and plays a key role in connective tissue remodeling, inflammatory processes and fibrosis in various illnesses including cancer. AIM: To investigate the role of CTGF in colorectal cancer (CRC) progression and to compare the CTGF expression with different clinicopathological parameters. METHODS: Real-time polymerase chain reaction, immunohistochemistry and Western blotting was performed to evaluate the CTGF expression and the results were statistically analyzed against the clinicopathological variables of patient data using STATA software version 16. RESULTS: CTGF expression levels in tumor specimens were significantly higher than their paired normal specimens. The higher protein expression levels showed a significant association with smoking, staging, tumor grade, invasion depth, necrosis of tumor tissue, and both lymphovascular and perineural invasion. As per the cox regression model and classification tree analysis, tumor-node-metastasis stage and perineural invasion were important predictors for CTGF expression and prognosis of CRC patients. Survival analysis indicated that CTGF overexpression was associated with poorer overall and disease-free survival. CONCLUSION: Expression of CTGF was increased in CRC and was linked with poor overall and disease-free survival of CRC patients. These findings support prior observations and thus CTGF may be a possible prognostic marker in CRC.


Asunto(s)
Neoplasias Colorrectales , Factor de Crecimiento del Tejido Conjuntivo , Neoplasias Colorrectales/patología , Factor de Crecimiento del Tejido Conjuntivo/genética , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Humanos , Inmunohistoquímica , Pronóstico , Análisis de Supervivencia
10.
Pathol Res Pract ; 231: 153791, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35124548

RESUMEN

BACKGROUND AND AIMS: TEAD4 transcription factor belonging to TEAD-family, is a key downstream element of the Hippo Signalling pathway and is very important for YAPinduced tumor progression. YAP-TEAD interaction is required to promote tumor progression and metastasis in various cancers. This study aims to investigate the role of TEAD4 in CRC progression and to compare the TEAD4 expression with different clinicopathological parameters of the study population. We also aim to explore the expression pattern of miR-4269 and miR-1343-3p and their functional role in TEAD4 mediated CRC progression. Furthermore, we intend to evaluate the prognostic significance of TEAD4, miR-4269, and miR-1343-3p in colorectal carcinoma. METHODS: Real-time PCR, Immunohistochemical Staining, and Western Blotting were performed on 71 human CRC tissue specimens and their adjacent normal tissues to evaluate the TEAD4 expression and the results were statistically analyzed against the clinicopathological variables of patient data and also with survival data using STATA software. miRNA expression was analyzed by quantitative real-time PCR. RESULTS: TEAD4 expression levels in tumor specimens were significantly higher than their paired normal specimens. The higher protein expression levels showed a significant association with TNM stage, Duke Stage, tumor grade, invasion depth, node status, necrosis of tumor tissue, lymphovascular and perineural invasion. As per the cox-regression model and classification tree analysis, TNM stage and perineural invasion were important predictors for TEAD4 expression and prognosis of CRC patients. Survival analysis indicated that TEAD4 overexpression was associated with poorer overall and disease-free survival. miR-4269 and miR-1343-3p were downregulated in CRC tumors and showed a negative correlation with TEAD4. The nuclear overexpressed TEAD4 and downregulated miR-4269 and miR-1343-3p evaluated for the first time in CRC, are believed to serve as important prognostic markers in CRC. CONCLUSION: Expression of TEAD4 was increased in CRC and was negatively regulated by miR-4269 and miR-1343-3p. The overexpression of TEAD4 is linked with poor overall and disease-free survival of CRC patients. These findings support prior observations and thus TEAD4 may be a possible prognostic marker in CRC.


Asunto(s)
Neoplasias Colorrectales/genética , Expresión Génica/fisiología , MicroARNs/metabolismo , Factores de Transcripción de Dominio TEA/genética , Línea Celular Tumoral/metabolismo , Femenino , Humanos , Masculino , MicroARNs/análisis , Persona de Mediana Edad , Señales de Localización Nuclear/genética , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Transcripción de Dominio TEA/análisis , Factores de Transcripción de Dominio TEA/metabolismo
11.
Angew Chem Int Ed Engl ; 60(38): 20734-20738, 2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34270852

RESUMEN

We report the synthesis of a (2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl) (TEMPO) appended polymonothiocarbonates through the ring-opening copolymerization of (4-glycidyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl) (GTEMPO) in the presence of carbonyl sulfide under ambient conditions. We have prepared the atactic and isotactic versions of this polymer, using enantiopure R or S forms of the GTEMPO monomer in the latter instances. Cyclic voltammetry studies revealed both oxidation and reduction events that were characteristic of TEMPO radicals. Electrical conductivity of these polymers was measured as solid-state films after annealing the samples above their glass transition temperatures. At room temperature the isotactic polymer shows much greater conductivity (ca. 10-4  S cm-1 ) than the atactic (ca. 10-7  S cm-1 ), attributed to the well-defined stereochemistry and regulated charge transport pathway of isotactic polymer chains in contrast to the irregular structure of the atactic counterpart.

12.
Angew Chem Int Ed Engl ; 59(32): 13633-13637, 2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-32372553

RESUMEN

Topological polymers possess many advantages over linear polymers. However, when it comes to the poly(monothiocarbonate)s, no topological polymers have been reported. Described herein is a facile and efficient approach for synthesizing well-defined branched poly(monothiocarbonate)s in a "grafting through" manner by copolymerizing carbonyl sulfide (COS) with epichlorohydrin (ECH), where the side-chain forms in situ. The lengths of the side-chains are tunable based on reaction temperatures. More importantly, enhancement in thermal properties of the branched copolymer was observed, as the Tg  value increased by 22 °C, compared to the linear analogues. When chiral ECH was utilized, semicrystalline branched poly(monothiocarbonate)s were accessible with a Tm  value of 112 °C, which is 40 °C higher than that of the corresponding linear poly(monothiocarbonate)s. The strategy presented herein for synthesizing branched polymers provides efficient and concise access to topological polymers.

13.
Chemphyschem ; 21(8): 814-820, 2020 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-32124533

RESUMEN

We chose to understand the cyclic instability and rate instability issues in the promising class of Na+ conversion and alloying anodes with Sb2 Se3 as a typical example. We employ a synthetic strategy that ensures efficient rGO (reduced graphene oxide) wrapping over Sb2 Se3 material. By utilization of the minimum weight of additive (5 wt.% of rGO), we achieved a commendable performance with a reversible capacity of 550 mAh g-1 at a specific current of 100 mA g-1 and an impressive rate performance with 100 % capacity retention after high current cycling involving a 2 Ag-1 intermediate current step. The electrochemical galvanostatic intermittent titration technique (GITT) has been employed for the first time to draw a rationale between the enhanced performance and the increased mobility in the rGO wrapped composite (Sb2 Se3 -rGO) compared to bare Sb2 Se3 . GITT analysis reveals higher Na+ diffusion coefficients (approx. 30 fold higher) in the case of Sb2 Se3 -rGO as compared to bare Sb2 Se3 throughout the operating voltage window. For Sb2 Se3 -rGO the diffusion coefficients in the range of 8.0×10-15  cm2 s-1 to 2.2×10-12  cm2 s-1 were observed, while in case of bare Sb2 Se3 the diffusion coefficients in the range of 1.6×10-15  cm2 s-1 to 9.4×10-15  cm2 s-1 were observed.

14.
Angew Chem Int Ed Engl ; 58(47): 16844-16849, 2019 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-31518046

RESUMEN

Manipulation of low-dimensional solids through soft chemical routes is an elegant way to realize newer materials. A new family of single-crystalline transition-metal layered organophosphates, with about 185 000 metal phosphate layers in a single crystal, can be exfoliated to a single-layer nanosheet by a facile and rapid solvent assisted method. This exfoliation aids the formation of high-surface-area pyrophosphates with enhanced supercapacitance.

15.
Inorg Chem ; 57(13): 7644-7654, 2018 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-29906112

RESUMEN

The reaction of [Cp*TiCl3] (Cp* = C5Me5) with monoalkyl phosphates (RO)PO3H2 (R = Me, Et, and iPr) in tetrahydrofuran (THF) at 25 °C leads to the formation of binuclear complexes [Cp*2Ti2(µ-O2P(OH)OR)2(µ-O2P(O)OR)2] [R = Me (1), Et (2), and iPr (3)]. On the other hand, the reaction of ( tBuO)2PO2K with [Cp*TiCl3] in acetonitrile or THF results in isolation of either the dinuclear [Cp*2Ti2(µ-O2P(OH)O tBu)2(µ-O2P(O)O tBu)2] (4) or the trinuclear titanophosphate [Cp*3Ti3(µ-O3PO tBu)2(µ-O)2(µ-O2P(O tBu)2)] (5), respectively. The formation of compounds 4 and 5 is facilitated by partial hydrolysis of the tert-butoxy groups of ( tBuO)2PO2K. New titanophosphates 1-5 have been characterized by spectroscopic and analytical methods, and the molecular structures have further been confirmed by single-crystal X-ray diffraction studies. Thermal decomposition studies of 1-5 reveal the initial loss of thermally labile alkyl substituents of the organophosphate ligands, followed by the loss of C5Me5 groups to form an organic-free amorphous titanophosphate in the temperature range 300-500 °C. This material transforms to highly crystalline titanium pyrophosphate TiP2O7 at 800 °C. Compounds 1-5 and the TiP2O7 materials obtained at 300, 500, and 800 °C through the thermal decomposition of 3 have been employed as efficient homogeneous catalysts for the alkene epoxidation reaction. Using hydrogen peroxide as the oxidant in an acetonitrile medium, these catalysts exhibit >90% alkene conversion with >90% epoxide selectivity in 4 h at temperatures below 100 °C.

16.
Asian Pac J Cancer Prev ; 18(11): 2925-2930, 2017 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-29172260

RESUMEN

Background: Polycystic ovary syndrome (PCOS), associated with a state of low grade chronic inflammation, depends on multiple genetic and environmental factors. Elevated levels of inflammatory markers including intercellular adhesion molecule-1 (ICAM-1) have been demonstrated in affected women. Recent evidence indicates a significant linkage between chromosome 19p13 loci and multifactorial diseases that have an inflammatory component. The aim of this study was to assess the possible association of the lys469glu (K469E) polymorphism of the ICAM-1 gene located on chromosome 19p13 with risk of PCOS in Kashmiri women. Material and Methods: The K469E single nucleotide polymorphism (SNP) was analysed with DNA from peripheral blood leukocytes of 220 PCOS cases and 220 age matched non-PCOS healthy controls using PCR-RFLP. Results: Genotypic frequencies in cases were found to be 32 (14.5%) for EE, 98 (44.5%) for KE, and 90 (40.9%) for KK, with 130 (59.1%) for the KE+EE genotypes compared to healthy control values of 29 (13.2%) for EE, 113 (51.4%) for KE, 78 (35. 5%) for KK and 142 (64.5%) for KE+EE combined.The odds ratios for the EE, KE and KE:EE genotypes were 0.95(95% CI= 0.53-1.71)[p= 0.88], 0.75(95% CI= 0.50-1.12)[p =0.168] and 0.79 (95% CI =0.53-1.16) [p = 0.23], no statistically significant differences being found between cases and controls (χ2 =2.07; p=0.35). Conclusion: In conclusion, there was no apparent significant influence of the K469E polymorphism on risk of PCOS, or any clinical or laboratory parameters.

17.
Dalton Trans ; 46(39): 13409-13420, 2017 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-28948250

RESUMEN

Copper phosphate metalloligands [Cu(X-dipp)(Pyterpy)]2 [X = H (1), Br (2)], exemplifying expanded 4,4'-bipyridine type molecules, have been synthesized by reacting 4'-(4-pyridyl)-2,2':6',2''-terpyridine (Pyterpy) and para substituted 2,6-diisopropylphenyl phosphate (X-dippH2) with copper acetate. The pendant N,N-ends of dimeric copper phosphates 1 and 2 have been forced to engage in further coordination by limiting the concentration of Pyterpy in the reaction mixture to yield rare Pyterpy bridged corner-shared polymeric copper phosphates [Cu2(X-dippH)(X-dipp)(Pyterpy)(H2O)]n [X = Cl (3), Br (4), I (5)]. The formation of 1-5 is supported by spectroscopic and analytical data. The solid state structures of these compounds have further been confirmed by single-crystal X-ray diffraction studies. Soluble dimeric complexes 1 and 2 have been assessed for their in vitro anti-tumour properties against human breast and colorectal cancer cell lines. The DNA cleavage, protein cleaving and cytotoxicity assays revealed that these compounds are effective in cleaving DNA, while the activity of 1 as an anti-tumor agent is better than 2.


Asunto(s)
Antineoplásicos/química , Complejos de Coordinación/química , Cobre/química , ADN/metabolismo , Organofosfatos/química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Bovinos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Complejos de Coordinación/farmacología , Cristalografía por Rayos X , ADN/química , División del ADN/efectos de los fármacos , Humanos , Microscopía Confocal , Conformación Molecular , Plásmidos/química , Plásmidos/metabolismo , Albúmina Sérica Bovina/química , Albúmina Sérica Bovina/metabolismo , Espectrometría de Masa por Ionización de Electrospray
18.
Inorg Chem ; 56(15): 9071-9083, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-28741937

RESUMEN

Spirocyclic lanthanide organophosphate polymers, {[Ln(dipp)(dippH)(CH3OH)(H2O)2](CH3OH)2}n [Ln = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Ho (10), Er (11)], have been prepared from the reaction of Ln(NO3)3·xH2O with sterically hindered 2,6-diisopropylphenyl phosphate (dippH2) using aqueous NaOH as the base. The one-dimensional chainlike lanthanide (III) organophosphate coordination polymers have been characterized with the aid of analytical and spectroscopic methods. The single crystal structure determination of polymers (2-5 and 7-11) reveals that in these compounds the hydrophobic organic groups of the phosphate provide a protective coating for the inorganic lanthanide phosphate polymeric chain. The encapsulation of inorganic lanthanide phosphate core, which has very low solubility product, within the organic groups assists in the facile crystallization of the polymers. The di- and monoanionic organophosphate ligands dipp2- and dippH- display [2.111] and [2.110] binding modes, respectively, in 2-5 and 7. However, they exhibit only [2.110] binding mode in the case of 8-11. This results in the formation of two different types of polymers. While the lighter rare-earth metal ions in 2-5 and 7 display eight coordinate biaugmented trigonal prismatic geometry, the heavier rare-earth metal ions in 9-11 exhibit a seven coordinate capped trigonal prismatic environment. The Tb(III) ion in 8 displays distorted pentagonal bipyramidal geometry. Magnetic studies reveal the presence of weak antiferromagnetic interactions between the Ln(III) ions through the organophosphate ligand. The isotropic Gd(III) polymer 7 exhibits a maximum entropy change of 17.83 J kg-1 K-1 for a field change of 7.0 T at 2.5 K, which is significant considering the high molecular weight of the organophosphate ligand. These polymers represent the first family of any structurally characterized rare-earth organophosphate polymers derived from monoesters of phosphoric acid.

19.
Inorg Chem ; 55(11): 5180-90, 2016 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-27159770

RESUMEN

4,4'-Bipyridine-N-oxide (BIPYMO, 1), a less commonly employed coordination polymer linker, has been used as a ditopic spacer to bridge double-four-ring (D4R) zinc phosphate clusters to form novel framework coordination polymers. Zinc phosphate framework compounds [Zn4(X-dipp)4(BIPYMO)2]n·2MeOH [X = H (2), Cl (3), Br (4), I (5); dipp = 2,6-diisopropylphenyl phosphate] have been obtained by treating a methanol solution of zinc acetate with X-dippH2 and BIPYMO (in a 1:1:1 molar ratio) at ambient conditions. Framework phosphates 2-5 can also be obtained by treating the preformed D4R cubanes [Zn(X-dipp)(DMSO)]4 with required quantities of BIPYMO in methanol. Single-crystal X-ray diffraction studies reveal that these framework solids are two-dimensional (2D) networks as opposed to the diamondoid networks obtained when the parent unoxidized 4,4'-bipyridine is used as the linker (Inorg. Chem. 2014, 53, 8959). The two types of voids (viz., smaller intra-D4R and larger inter-D4R) present in these framework solids can be utilized for different types of encapsulation processes. For example, the in situ generated 2D framework 2 encapsulates fluoride ions accompanied by a change in the dimensionality of the framework to yield {[(nC4H9)4N][F@(Zn4(dipp)4(BIPYMO)2)]}n (6). The three-dimensional framework 6 represents the first structurally characterized example of a fluoride-ion-encapsulated polymeric coordination compound or a metal-organic framework. The possibility of utilizing inter-D4R voids as hosts for small organic molecules has been explored by treating in situ generated 2 with a series of organic molecules of appropriate size. Framework 2 has been found to be a selective host for benzil and not for other structurally similar molecules such as benzoquinone, benzidine, anthracene, naphthalene, α-pyridoin, etc. The benzil-occluded isolated framework [benzil@{Zn4(dipp)4(BIPYMO)2}]n (7) has been isolated as single crystals, and its crystal structure determination revealed the binding of benzil molecules to the framework through strong π-π interactions.

20.
Nat Prod Commun ; 10(3): 503-4, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25924539

RESUMEN

Crocetenone, a new rotenoid (1), along with five known compounds apocyanin (2), tectorigenin (3), 5,2',3'-trihydroxy-7-methoxy flavanone (4), tectoridin (5) and tectoridin glycoside (6), were isolated from the methanolic extract of the root of Iris crocea. The structure of compounds was elucidated on the basis of 1D- and 2D-NMR spectroscopic and MS analysis. Antibacterial and antioxidant activities of compounds 1-6 were evaluated. Crocetenone (1) showed a prominent antibacterial activity.


Asunto(s)
Género Iris/química , Isoflavonas/química , Estructura Molecular , Rizoma/química
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