Mono Derivatives Research Articles

Mono(Amino Acid) Derivatives of Fullerenes, Hybrid Structures on Their Basis and Their Biological Activity

The synthesis and biological properties of mono(amino acid) derivatives of fullerenes (MAADFs) as well as hybrid nanostructures (HNSs) on their basis are reviewed. It is shown that these derivatives are highly effective non-toxic compounds in various fields of medicine and can be further used as potential drugs.

Efficient synthesis of acetylene-bridged carbazole-based dimer for electrochemical energy storage: Experimental and DFT studies

The energy storage prospects of organic molecule has recently rendered them as promising candidates for supercapacitors (SCs) applications. Herein, we report an investigation into the electrochemical and energy storage capability of two carbazole based monomer and dimer moieties, connected through mono (CBZ-1) and diacetylene (CBZ-2)-based linkages. Synthesized intermediates and final compounds were experimentally and theoretically characterized via spectral, scanning electron microscopy (SEM) analysis and density functional theory (DFT) calculations respectively. Excellent electrochemical properties were observed in an organic pseudo-capacitive-supercapacitor (SC) based on the carbazole derivatives, with the dimer (CBZ-2) functionalized with diacetylene showing a comparatively better capacitive and improved electrochemical characteristics (398F.g −1 at a current density of 1 A.g −1 ) than the mono (CBZ-1) derivative.

Agro-Waste Generated Pd/CAP-Ash Catalyzed Ligand-Free Approach for Suzuki–Miyaura Coupling Reaction

We converted agro-waste Custard Apple Peels (CAP) to ash via thermal treatment, on which Pd(OAc)2 was immobilized easily that produced a low-cost, highly efficient Pd/CAP-ash catalyst. The prepared catalyst was fully characterized by using FT-IR, SEM, EDX, XRF, DSC-TGA, BET, HR-TEM, and XPS techniques. The Pd/CAP-ash catalyst was conveniently applied for the Suzuki–Miyaura coupling reaction under external base free and ligand-free conditions in an aqueous-organic solvent to produce biphenyls in good to excellent yields. The main attraction of our protocol an application of palladium-supported agro-waste material which is easily recoverable and recyclable provides mono and bis-coupled derivatives in a short reaction time.

Regioselective synthesis of some novel indanone chalcones and their antimicrobial activity

A series of novel indanone chalcones were obtained regioselective mono derivatives by condensation of bis-aldehydes with indanone using potassium hydroxide as base. The newly synthesized chalcones were characterized using different analytic methods such as IR, 1 HNMR, 13 CNMR, mass spectrometry and elemental analysis. Results of antimicrobial screening evident that most synthesized derivatives were shows moderate to good activity against all tested organism.

Investigation of the aromaticity of mono, di, tri and tetraazaphenanthrene derivatives

AbstractIn this chapter mono, di, tri and tetraaza substituted phenanthrene derivatives have been investigated computationally with B3LYP/6-31 + G(d,p) level of theory. Substitution of carbon atom of the main structure with nitrogen obviously disturbs the aromaticity, indeed it decreases it. Thus, the idea of regaining of the aromaticity back by using electron withdrawing groups came across. As a result of the computational calculations, energetically most unfavored structures have been found to be those where aza substitutiona are vicinal. Secondly, the aromaticities of the present species depend on the position of the centric substituent. In addition, the effect position of the side substituent has been considered. The system becomes more aromatic (possess greater negative NICS values or smaller HOMA value) when the electron withdrawing atoms or groups are adjacent to the centrically substituted heteroatoms.

The mono(catecholamine) derivatives as iron chelators: synthesis, solution thermodynamic stability and antioxidant properties research.

There is a growing interest in the development of new iron chelators as novel promising therapeutic strategies for neurodegenerative disorders. In this article, a series of mono(catecholamine) derivatives, 2,3-bis(hydroxy)-N-(hydroxyacyl)benzamide, containing a pendant hydroxy, have been synthesized and fully characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy and mass spectrum. The thermodynamic stability of the chelators with FeIII, MgII and ZnII ions was then investigated. The chelators enable formation of (3 : 1) FeIII complexes with high thermodynamic stability and exhibited improved selectivity to FeIII ion. Meanwhile, the results of 1,1-diphenyl-2-picryl-hydrazyl assays of mono(catecholamine) derivatives indicated that they all possess excellent antioxidant properties. These results support the hypothesis that the mono(catecholamine) derivatives be used as high-affinity chelator for iron overload situations without depleting essential metal ions, such as MgII and ZnII ions.

Effect of Pluronic F-127 on the photosensitizing activity of tetraphenylporphyrins in organic and aqueous phases

The solubilization of hydrophobic porphyrin photosensitizers (PPSes) to obtain corresponding water-soluble forms is an important line of modern antimicrobial photodynamic therapy. It is shown that a triblock copolymer of ethylene and propylene oxides, Pluronic F-127, one of the most nontoxic and effective polymer surface active substances (SASes), can be used for the conversion of hydrophobic tetraphenylporphyrin (TPP) and monosubstituted and tetrasubstituted hydroxy, amino, and nitro TPPs into water-soluble forms. It is found that Pluronic has a substantially higher solubilizing affinity (defined as the minimum molar concentration of an SAS required for the complete migration of porphyrin with a specific molar concentration to the aqueous phase) toward monosubstituted TPPs than to corresponding tetrasubstituted porphyrins. It is shown that with Pluronic in the organic phase, the activity of tetraphenylporphyrin in a test reaction of the oxidation of anthracene is higher than that of its monosubstituted and tetrasubstituted derivatives. In an aqueous medium, the activity of solubilized mono derivatives of TPP is comparable to that of unsubstituted TPP and is higher than the activity of the corresponding tetra derivatives of TPP.

ChemInform Abstract: Synthesis of Bifunctional Chelating Agents Based on Mono and Diphosphonic Derivatives of Diethylenetriaminepentaacetic Acid.

Abstract Bifunctional chelating agents (BFCAs) are small molecules containing a chelating unit, able to strongly coordinate a metal ion, and a reactive functional group, devised to form a stable covalent bond with another molecule. BFCAs are widely employed since their conjugation to a suitable biomolecule (e.g., a peptide or an antibody) allows the synthesis of diagnostic or therapeutic agents that specifically target diseased tissue with metals or radiometals. For this reason, BFCAs find application in diagnostic imaging, molecular imaging, and radiotherapy of cancer. The synthesis of new BFCAs based on a diethylenetriaminepentaacetic acid (DTPA) structure in which one or two carboxylic groups are replaced with phosphonic units is described. The phosphonic group, aside from being a classical isostere of the carboxylic acid in coordination chemistry, allows to modulate the physico-chemical properties of the ligands and of the corresponding complexes.

Synthetic, redox and coordination chemistry of bis(pentachlorophenyl)boryl ferrocene, FcB(C6Cl5)2

Two synthetic approaches to bis(pentachlorophenyl)boryl ferrocene have been explored. One mirrors that used in a novel approach to FcB(C6F5)2 from FcBBr2, but is less selective than its perfluorinated counterpart on account of the greater steric bulk of LiC6Cl5 over LiC6F5. This approach does, however, provide a viable route to unsymmetrical mono(pentachlorophenyl) derivatives of the type FcB(C6Cl5)Ar through the intermediacy of the mono-substituted species FcB(C6Cl5)Br. FcB(C6Cl5)2 itself is best synthesized from ferrocenyllithum and ClB(C6Cl5)2 and is a violet–blue species featuring an extremely electron deficient Fe(II) centre (E1/2 = +550 mV with respect to ferrocene/ferrocenium). A combination of structural, spectroscopic and reactivity studies of these and related ferrocenylboranes allow some general comments to be made concerning the relative steric and electronic properties of the C6Cl5 group. Thus, in terms of their relative capabilities as electron-withdrawing groups the substituents examined can be ranked C6Cl5 > C6F5 > Mes, while steric properties are ordered Mes > C6Cl5 > C6F5.

Syntheses and characterization of liposome-incorporated adamantyl aminoguanidines

A series of mono and bis-aminoguanidinium adamantane derivatives has been synthesized and incorporated into liposomes. They combine two biomedically significant molecules, the adamantane moiety and the guanidinium group. The adamantane moiety possesses the membrane compatible features while the cationic guanidinium subunit was recognized as a favourable structural feature for binding to complementary molecules comprising phosphate groups. The liposome formulations of adamantyl aminoguanidines were characterized and it was shown that the entrapment efficiency of the examined compounds is significant. In addition, it was demonstrated that liposomes with incorporated adamantyl aminoguanidines effectively recognized the complementary liposomes via the phosphate group. These results indicate that adamantane derivatives bearing guanidinium groups might be versatile tools for biomedical application, from studies of molecular recognition processes to usage in drug formulation and cell targeting.

A Novel Heterobimetallic [Mg(II)-Sn(IV)]-μ-oxoisopropoxide and Its β-Diketonates: Synthesis, Analytical and Pyrolysis Studies

In the present study, a novel heterobimetallic [Mg(II)-Sn(IV)]-μ-oxoisopropoxide [MgO2Sn2(OPri)6] and its β-diketonates have been synthesized and characterized. The parent compound has been synthesized by the thermal condensation of magnesium acetate and tin(IV) isopropoxide. The isopropoxy substitution reactions of μ-oxoisopropoxide compound with β-diketones in different molar ratios (1:1–1:4) yielded the mono derivatives to tetra derivatives respectively of the parent compound. [{MgO2Sn2(OPri)6-nLn} (where n is 1–4 and L = acetylacetonate/benzoylacetonate anion)]. The μ-oxoisopropoxide compound has been characterized by liberated isopropanol, elemental, spectral (IR, 1H, 13C, 119Sn NMR, and mass), thermal analysis, molecular weight data, and plausible structure is suggested. Some important reactions of [MgO2Sn2(OPri)6] with different β-diketones have revealed interesting facets in support of the suggested structure. The β-diketonates have been characterized by elemental, liberated isopropanol and spectral analysis (IR, 1H, 13C NMR).

Synthesis of Supramolecular Organogels Derived from Urea and Bisurea Derivatives of Dehydroabietylamine

The gelation ability of diterpenes was investigated by applying aromatic linker steroid strategy. Four new mono (1) and bis-urea (2–4) derivatives of dehydroabietylamine (DAA) (a tricyclic diterpene amine) were synthesized on reaction of respective isocyanates with DAA and characterized through spectroscopic data. Three of these (1, 2, and 4) were obtained as low-molecular-weight organogelators that can form thermally reversible organogels. Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for full experimental and spectral details.

ChemInform Abstract: Carbohydrate‐Derived Auxiliaries: Mono (and Disaccharide) Derivatives

AbstractReview: 448 refs.

Solvation of benzene and its simple mono derivatives in water-tertiary butanol mixtures

This paper focuses on the energetics of solvation of slightly soluble aromatic solutes – benzene (C6H6), nitrobenzene (C6H5NO2) and aniline (C6H5NH2) in the mixtures of water with hydrophobic tertiary butanol (t-BuOH). Standard enthalpies of solvation for all of the solutes studied are found to reveal the abnormal dependence from the alcohol content in the mixed solvent. It passes through the pronounced maximum at Xt-BuOH≈0.05mol fractions, the position of which is nearly equal to the mixed solvent composition, where alcohol molecules begin to aggregate forming small hydrophobic clusters. The enthalpic cost for accommodation of the hydrophobic benzene ring into these aggregates is likely to cause this abnormal solute behavior. The height of the maxima observed is found to depend on nature of a functional group in the solute molecule. Hydrophilic amino group forming strong H-bonds with surrounding water molecules decreases the extremum, whereas aromatic nitro group induces its significant increase.

At the center of the circle: purinergic signaling in the autocrine loops of pancreatic islets

AbstractThe endocrine pancreas is essential for monitoring and regulating the metabolic status of the body by sensing changes in glucose and free fatty acids and respond by secreting hormones such as insulin and glucagon. Although pancreatic islets only make up a small percentage of the pancreas mass, its malfunction causes severe disease. Despite insulin treatment, and the development of novel antidiabetic drugs, diabetes is still one of the most costly and invaliding diseases, leaving an open arena for drug target discovery within the endocrine pancreas. Purinergic receptors are a class of receptors, which has already been utilized as a successful antithrombotic drug target used in secondary prevention after myocardial infarction. The versatility and broad expression of these receptors make them interesting for pharmacological manipulation in treatment of disease. Purinergic receptors include four G‐protein coupled adenosine receptors (A1, A2A, A2B, and A3), eight G‐protein coupled nucleotide (ATP, ADP, UTP, UDP, UDP‐glucose) gated receptors (P2Y1, P2Y2, P2Y4, P2Y6, P2Y11, P2Y12, P2Y13, and P2Y14), and finally seven ATP‐gated ion channels (P2X1‐7). Ectonucleotidases degrade nucleotides to their di‐ and mono derivatives, which in turn can stimulate their favored P2 receptor. Adenosine monophosphate (AMP) is finally hydrolyzed to adenosine, which in turn can act on adenosine receptors. Each P2Y receptor couples to different G‐proteins leading to different intracellular pathways downstream of stimulation. WIREs Membr Transp Signal 2013, 2:107–119. doi: 10.1002/wmts.82For further resources related to this article, please visit the WIREs website.The authors have declared no conflicts of interest for this article.

Synthesis of Conjugated Aryleneethynylenesiloles Dendron

AbstractThree routes were designed to synthesize a π‐conjugated aryleneethynylenesiloles dendron. With the desilylation of the disilole mono(silylethynyl) derivative in the presence of potassium carbonate (K2CO3), the silole‐containing oligomer has been successfully synthesized without impact on the Si‐(CH3)2 group. The disilole mono(silylethynyl) derivative was prepared by means of the Sonogashira heterocoupling reaction between the diacetylene compound and asymmetrical silole, catalyzed by the dichloro bis(triphenylphosphine)palladium, in a divergent synthesis. Due to their steric effect and triethynylbenzene self‐coupling Glaser reaction, the endeavour to prepare the dendron by controlling the molar ratio of asymmetrical silole and 1,3,5‐triethynylbenzene was failed. The another attempt to prepare the dendron by different desilylation condition of triisopropylsilyl group and trimethylsilyl group was also failed, the desilylation of Si‐(CH3)2 group in silacyclopentadiene unit was also easily accomplished in the presence of tetrabutylammonium fluoride(Bu4NF), whereas no reaction occurred when K2CO3 was used instead of Bu4NF.

Artificial enzymes based on cyclodextrin with phenol as the catalytic group

β-Cyclodextrin containing one or two N-linked ortho-N-acetylaminophenols has been synthesized and tested for their properties as artificial glycosidases. Four different para-nitrophenyl glycosides were used as substrates and kcat/kuncat values of up to 381 were found for the di-functionalized products, whereas the mono derivative showed up to 47 times rate enhancement. The optimum pH for the catalysis was found to be approximately pH 8 and the influence of phosphate concentration was investigated.

Gallium(III) Complexes of DOTA and DOTA−Monoamide: Kinetic and Thermodynamic Studies

Given the practical advantages of the (68)Ga isotope in positron emission tomography applications, gallium complexes are gaining increasing importance in biomedical imaging. However, the strong tendency of Ga(3+) to hydrolyze and the slow formation and very high stability of macrocyclic complexes altogether render Ga(3+) coordination chemistry difficult and explain why stability and kinetic data on Ga(3+) complexes are rather scarce. Here we report solution and solid-state studies of Ga(3+) complexes formed with the macrocyclic ligand 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid, (DOTA)(4-), and its mono(n-butylamide) derivative, (DO3AM(Bu))(3-). Thermodynamic stability constants, log K(GaDOTA) = 26.05 and log K(GaDO3AM(Bu)) = 24.64, were determined by out-of-cell pH-potentiometric titrations. Due to the very slow formation and dissociation of the complexes, equilibration times of up to ∼4 weeks were necessary. The kinetics of complex dissociation were followed by (71)Ga NMR under both acidic and alkaline conditions. The GaDOTA complex is significantly more inert (τ(1/2) ∼12.2 d at pH = 0 and τ(1/2) ∼6.2 h at pH = 10) than the GaDO3AM(Bu) analogue (τ(1/2) ∼2.7 d at pH = 0 and τ(1/2) ∼0.7 h at pH = 10). Nevertheless, the kinetic inertness of both chelates is extremely high and approves the application of Ga(3+) complexes of such DOTA-like ligands in molecular imaging. The solid-state structure of the GaDOTA complex, crystallized from a strongly acidic solution (pH < 1), evidenced a diprotonated form with protons localized on the free carboxylate pendants.

Triphenylene/carbazole mesogens and their electrochemistry

The synthesis of 10 discotic mesogens is described in which the well-known hexaalkyloxytriphenylene liquid crystalline core has been covalently linked to incorporate one and three carbazole moieties. These modifications have been achieved by the esterification of mono and tris hydroxy triphenylene derivatives with carboxylic acids incorporating 3,6-bisalkylated or 3,6-bisacylated carbazole moieties. The pure compounds are not liquid crystalline and neither are they when doped with TNF, unlike similar materials that were reported previously, where the carbazole moiety was not 3,6-bisalklylated or 3,6-bisacylated, which when doped with TNF did display mesophases. The solution state cyclic voltammetry of selected materials is reported.

Fluorescence properties of novel 6-butyl-2,3-dicyano-7-methyl-6 H-1,4-diazepine styryl dyes containing ethyleneglycol units

The fluorescence properties of novel 6-butyl-2,3-dicyano-7-methyl-6 H-1,4-diazepine styryl dyes having mono-, di-, tri-, and tetra(ethyleneglycol) units were examined. The mono(ethylenglycol) derivative was solid at room temperature, whereas the di-, tri-, and tetra(ethylenglycol) derivatives were oily. The monoethyleneglycol derivative showed weak aggregation-induced emission enhancement with fluorescence maximum at 649 nm, which comes from J-aggregates. The fluorescence of oily di-, tri-, and tetra(ethyleneglycol) derivatives in neat form was very weak. No aggregation-induced emission enhancement was observed for the oily derivatives.