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1.
Curr Pharm Biotechnol ; 23(2): 261-275, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33845735

RESUMO

The Mediterranean diet is appraised as the premier dietary regimen, and its espousal is correlated with the prevention of degenerative diseases and extended longevity. The consumption of olive oil stands out as the most peculiar feature of the Mediterranean diet. Olive oil rich in various bioactive compounds like oleanolic acid, oleuropein, oleocanthal, and hydroxytyrosol is known for its antiinflammatory as well as cardioprotective property. Recently in silico studies have indicated that phytochemicals present in olive oil are a potential candidate to act against SARS-CoV-2. Although there are many extensive studies on olive oil and its phytochemical composition, however, some lacunas persist in understanding how the phytochemical composition of olive oil is dependent on upstream processing. The signaling pathways regulated by olive oil in the restriction of various diseases are also not clear. For answering these queries, a detailed search of research and review articles published between 1990 to 2019 were reviewed. Olive oil consumption was found to be advantageous for various chronic non-communicable diseases. Olive oil's constituents are having potent anti-inflammatory activities and thus restrict the progression of various inflammation-linked diseases ranging from arthritis to cancer. But it is also notable that the amount and nature of the phytochemical composition of household olive oil are regulated by its upstream processing, and the physicochemical properties of this oil can give a hint regarding the manufacturing method as well as its therapeutic effect. Moreover, daily uptake of olive oil should be monitored as excessive intake can cause body weight gain and a change in the basal metabolic index. So, it can be concluded that the olive oil consumption is beneficial for human health, and particularly for the prevention of cardiovascular diseases, breast cancer, and inflammation. The simple way of processing olive oil is to maintain the polyphenol constituents, whichprovide the protection against noncommunicable diseases and SARS-CoV-2.


Assuntos
COVID-19 , Dieta Mediterrânea , Doenças não Transmissíveis , Humanos , Azeite de Oliva , SARS-CoV-2
2.
Org Biomol Chem ; 18(25): 4872, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32555903

RESUMO

Correction for 'Half-sandwich (η5-Cp*)Rh(iii) complexes of pyrazolated organo-sulfur/selenium/tellurium ligands: efficient catalysts for base/solvent free C-N coupling of chloroarenes under aerobic conditions' by Charu Sharma et al., Org. Biomol. Chem., 2020, 18, 3599-3606, DOI: 10.1039/D0OB00538J.

3.
Org Biomol Chem ; 18(18): 3599-3606, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32347877

RESUMO

Three new pyrazolated chalcogenoether ligated Rh(iii) half-sandwich complexes (1-3) were synthesised by the thermal reaction of chalcogenoether (S, Se and Te) substituted 1H-pyrazole ligands (L1-L3) and [(η5-C5Me5)RhCl]2 in methanol. The complexes were fully characterised by various spectroscopic techniques, and the molecular structures of complexes 1 and2 were also established through single crystal X-ray crystallographic analysis, which indicates a pseudo-octahedral half-sandwich piano-stool geometry around the rhodium metal. All three complexes were found to be thermally stable and insensitive towards air and moisture. One mol% of Rh(iii) complexes (1-3) along with 10 mol% of Cu(OAc)2 were explored for the Buchwald-Hartwig type C-N coupling reactions of amine and aryl chloride. Good to excellent yields (89-92%) of the coupling products were obtained with seleno- and thio-ether functionalised pyrazolated Rh(iii) complexes (1 and 2), while an average yield (39%) was obtained with the telluro-ether functionalised complex (3). In contrast to the previously reported C-N coupling reactions the present reaction works under solvent- and base-free conditions, and the coupling reaction is accomplished in just 6 h with a high yield of the coupling product. The present methodology was also found to be efficient for a wide variety of functionalised aryl halides, and aliphatic or aromatic amines (1° and 2°). Moreover, the reaction also enables the C-N coupling of electron-withdrawing substrates and base-sensitive functionalities.

4.
Org Biomol Chem ; 17(40): 8969-8976, 2019 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-31576395

RESUMO

A new 1-[N-benzylacetamido]-3-[1-(2-phenylselenylethyl)]benzimidazolium chloride (L), the precursor of a novel (Se, CNHC, N-)-type pincer ligand (L) was synthesised in high yield through a sequence of consecutive reactions of 1H-benzimidazole with ethylene dichloride, sodium selenophenolate, and N-benzyl-2-chloroacetamide. The palladium-promoted reaction of L with PdCl2 resulted in a moisture- and air-insensitive complex [Pd(L-H2Cl)Cl] (1), which demonstrated outstanding catalytic potential for Mizoroki-Heck coupling of aromatic bromides and chlorides (with yields up to 94% and 70%, respectively) at very low catalyst loading (0.2 mol%) and under mild reaction conditions in water. The complex (1) was also investigated for Suzuki-Miyaura coupling and found to be selectively efficient (yields up to 94%) for Suzuki-Miyaura coupling of aromatic bromides at 0.01 mol% of 1 in water. All coupling reactions were carried out in the green and economical solvent, water, which is highly desirable for bulk synthesis of complex molecules in industry. During the catalytic process, complex 1 converted into PdSe nanoparticles (NPs, size range 5-6 nm) in situ. The morphology and composition of these NPs were analysed through high-resolution transmission electron microscopy and transmission electron microscopy-energy dispersive X-ray spectroscopy, respectively. The core-level, X-ray photoelectron spectroscopy analysis confirmed the presence of stable Pd0 and Pd2+ oxidation states in these PdSe NPs. Based on further experimental investigations, these nanoparticles were found to work as a stock of true catalytic species. The hot filtration test, as well as the two-phase test, confirmed the largely homogeneous nature of the catalytic process, which probably proceeds by leaching of solution-phase Pd species from these NPs.

5.
Rev Sci Instrum ; 90(12): 123903, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31893822

RESUMO

Three indigenous systems-the underwater arc discharge setup, the inert environment arc discharge system, and the chemical vapor deposition (CVD) system-for the gram-scale production of carbon nanotubes were designed and fabricated. In this study, a detailed description of the development and fabrication of these systems is given. Carbon nanotubes were synthesized by using all the three systems, and comparative analyses of the morphology, composition, and purity were done. The synthesized materials were characterized using scanning electron microscopy, X-ray diffraction (XRD), and Raman spectroscopy. The scanning electron microscopy images show agglomerated tubed fiberlike structures in samples from the arc discharge setup, whereas samples from the CVD system do not show any tubelike structures decorated around the carbon nanotubes. Structural investigations done using powder XRD revealed the presence of the hexagonal crystallographic phase. Furthermore, the presence of the G and 2D bands reveals sp2 hybridization and confirms the presence of carbon nanotubes in samples. In conclusion, carbon nanotubes synthesized via the CVD system is of high quality and quantity. Moreover, the CVD is a cheap, easy to operate, and energy-saving synthesis method compared with the other two methods.

6.
Dalton Trans ; 43(32): 12365-72, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-24989230

RESUMO

The nanostructured magnetic oxide Fe3O4 has been coated with silica and then reacted with phenylselenyl chloride under a N2 atmosphere and RuCl3·xH2O successively in an aqueous medium to prepare Fe3O4@SiO2@SePh@Ru(OH)x nanoparticles (NPs) for the first time. These magnetically retrievable NPs have been authenticated using TEM, SEM-EDX and powder-XRD and found to be an efficient catalyst for one pot conversion (organic solvent not required) of aldehydes, nitriles and benzyl amine to primary amides in water. For aldehydes and nitriles, the yields of primary amides are up to 93%. These NPs can be recycled more than 7 times for the conversion of benzonitrile to the corresponding amide. Gram-scale transformation carried out by using Fe3O4@SiO2@SePh@Ru(OH)x NPs as a catalyst gives ∼86% yield.


Assuntos
Amidas/síntese química , Nanopartículas de Magnetita/química , Rutênio/química , Compostos de Selênio/química , Catálise , Fenômenos Magnéticos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Difração de Pó , Difração de Raios X
7.
Nanoscale ; 6(9): 4588-97, 2014 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-24626740

RESUMO

PdP2 and Pd4S nanoparticles (NPs) (size: ∼2-6 and 9-15 nm respectively) have been prepared for the first time from a single source precursor complex [Pd(L)Cl2] (1) by its one pot thermolysis at 200 °C in TOP and OA/ODE (1 : 1) respectively. These NPs were stirred with graphene oxide (GO) at room temperature to prepare NP composites, GO-PdP2 and GO-Pd4S. The GO-PdP2 NPs have been synthesized for the first time. The thioether ligand L prepared by reaction of 1,3-dibromo-2-propanol with the in situ generated PhSNa reacts with [PdCl2(CH3CN)2] in CH3CN at 70 °C resulting in 1. The L and 1 have been characterized by (1)H and (13)C{(1)H} NMR and HR-MS. The single crystal structure of 1 determined by X-ray diffraction reveals nearly square planar geometry around the Pd metal centre. The catalytic activities of two palladium nano-phases having phosphorus and sulphur respectively as a co-constituent for Suzuki-Miyaura coupling have been found to be exceptionally different, as PdP2 nanoparticles (NPs) grafted on graphene oxide (GO-PdP2) are significantly more efficient than Pd4S NPs grafted on GO. Without grafting PdP2 and Pd4S both have low efficiency. This is the first report comparing the influence of P and S on the catalytic activity of Pd NPs. TEM, SEM-EDX and powder-XRD have been used to authenticate all NPs. The GO-PdP2 NPs have been found to be efficient catalysts for Suzuki-Miyaura coupling reactions (yield up to 96% in 30 min) at room temperature to 80 °C. Their recyclability has been found up to 6 cycles. In contrast, GO-Pd4S NPs are little active in comparison with GO-PdP2 NPs. The size of NPs and their distribution on GO appear to be key factors affecting the catalytic efficiency of the composite NPs. Leaching of Pd from GO-PdP2 NPs contributes significantly to the catalysis as evidenced by the three phase test, hot-filtration and recycling experiments. The catalysis is almost homogeneous.

8.
Chem Commun (Camb) ; 49(81): 9344-6, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-23999625

RESUMO

The PdTe NPs (hexagonal) and nanorods (first example) have been synthesized for the first time from single source precursors (SSPs), [Pd(L1)Cl2] (1) and [Pd(L2)Cl]BF4 (2) [L1, 4-bromo-1-[2-(4-methoxyphenyltellanyl)ethyl]-1H-pyrazole; L2, bis-[2-(4-bromopyrazol-1-yl)ethyl]telluride], by their thermolysis in an OA­ODE mixture (1:1) and TOP respectively. The composition of the PdTe phase does not change with SSP/solvent. Complex 2 gives small size nanostructures.

9.
Chem Commun (Camb) ; 49(68): 7483-5, 2013 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-23689233

RESUMO

The Pd17Se15 nanoparticles, synthesized for the first time from a single source precursor [Pd(L)Cl2] {L = 1,3-bis(phenylselenyl)propan-2-ol} and grafted onto graphene oxide, show high catalytic activity in C-O coupling between aryl/heteroaryl chlorides/bromides and phenol at room temperature (Pd loading 1 mol%; yield up to 94%).

10.
Dalton Trans ; 42(24): 8736-47, 2013 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-23632941

RESUMO

The half sandwich complexes [(η(6)-C6H6)Ru(L)Cl][PF6] (1-5) have been synthesized by the reactions of (2-arylchalcogenomethyl)pyridine [L = L1-L3] and bis(2-pyridylmethyl)chalcogenide [L = L4-L5] (chalcogen = S, Se; Ar = Ph/2-pyridyl for S, Ph for Se) with [(η(6)-C6H6)RuCl2]2, at room temperature followed by treatment with NH4PF6. Their HR-MS, (1)H, (13)C{(1)H} and (77)Se{(1)H} NMR spectra have been found characteristic. The single crystal structures of 1-5 have been established by X-ray crystallography. The Ru has pseudo-octahedral half sandwich "piano-stool" geometry. The complexes 1-5 have been found efficient for catalytic oxidation of alcohols with N-methylmorpholine-N-oxide (NMO) and transfer hydrogenation of ketones with 2-propanol (at moderate temperature 80 °C) as TON values are up to 9.9 × 10(3) and 9.8 × 10(3) respectively for the two catalytic reactions. On comparing the required catalyst loading for good conversions and reaction time for the present complexes with those reported in literature for other transfer hydrogenation/oxidation catalysts, it becomes apparent that 1-5 have good promise. The complexes of Se ligands have been found more efficient than their sulphur analogues. The complexes of bidentate ligands are more efficient than those of terdentate, due to difficult bond cleavage in the case of latter. These orders of efficiency are supported by DFT calculations. The calculated bond lengths/angles by DFT are generally consistent with the experimental ones.

11.
Dalton Trans ; 42(7): 2366-70, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-23292353

RESUMO

The AgBr and Ag(2)Se nanoparticles (NPs) have been synthesized for the first time from two single source precursors ([Ag(2)(L)(2)Br(2)] (1) and [Ag(L-HBr)(2)]BF(4) (2) respectively) designed using the same ligand 3-benzyl-1-(2-phenylselanyl-ethyl)-3H-imidazolium bromide (L). The ODE-ODA-OA (1 : 1 : 2) and TOP-OA (1 : 2) are most suitable solvents for thermolysis of 1 and 2 respectively, resulting in the NPs. The composition of the solvent used in thermolysis affects the purity of NPs. The bonding of L in 1 is unique, as it has a pre-carbene site intact.


Assuntos
Brometos/química , Imidazóis/química , Nanopartículas/química , Selênio/química , Compostos de Prata/química , Brometos/síntese química , Modelos Moleculares , Estrutura Molecular , Tamanho da Partícula , Sais/química , Compostos de Prata/síntese química , Propriedades de Superfície
12.
Dalton Trans ; 42(11): 3908-18, 2013 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-23329305

RESUMO

The reactions of 4-bromo-1-(2-chloroethyl)-1H-pyrazole prepared from 4-bromopyrazole with the in situ generated PhSNa, PhSeNa, Na(2)S and Na(2)Se have resulted in thio/selenoether ligands L1-L4 respectively. The complexes [PdL1/L2Cl(2)](1-2) and [PdL3/L4Cl]BF(4) (3-4) of these ligands have been synthesized by reacting them with [PdCl(2)(CH(3)CN)(2)] in CH(3)CN at 70 °C. The L1-L4 and their complexes (1-4) have been characterized with spectroscopic techniques viz.(1)H, (13)C{(1)H} and (77)Se{(1)H} NMR, IR and HR-MS. Single crystal structures of 1-4 determined by X-ray diffraction reveal nearly square planar geometry around Pd in each case. Thermally stable, moisture/air insensitive complexes 1-4 have been found to be efficient pre-catalysts for Suzuki-Miyaura coupling reactions (yield up to 96% in 2 h). Nano-particles (NPs) (size ~3-19 nm) were formed in the beginning of these reactions. They are composed of Pd and S or Se with more % of Pd. These NPs also catalyze Suzuki coupling and appear to play an important role in catalysis. Single source one pot synthesis of Pd(4)Se and PdSe NPs (size ranges ~8-26 nm), capped with trioctylphosphine (TOP), has been developed by thermolysis of 2 and 4 at 200-250 °C in TOP. HR-TEM, SEM, SEM-EDX and powder XRD have been used to authenticate these nano-particles. The NPs of PdP(2) are formed when attempts were made to prepare nano-sized phases of palladium-sulfide by thermolysis of 1 and 3 in TOP.

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