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The unique structure of ricinoleic acid has been modified through esterification, amidation, hydration, epoxidation, oxidation, and hydrogenation reactions. The ricinoleic derivatives have been proven to have several biological activities such as anti-inflammatory, antitumor, antioxidant, and antimicrobial. In this research, methyl ricinoleate was prepared using methanol in the presence of acid as the catalyst. The methyl ricinoleate was purified using flash column chromatography with hexane-ethyl acetate 10:1 as the eluent to obtain 22.2% pure methyl ricinoleate. The methyl ricinoleate was subjected to an amidation reaction using ethanolamine to form a lipoamide. The reaction progress was monitored by TLC. The spot of lipoamide was lower than that of the methyl ricinoleate due to its higher polarity. The FTIR spectrum of lipoamide exhibited the presence of N-H absorption in the range of 3500-3000 cm−1, C=O amide absorption at 1644 cm−1, and C-N absorption at 1061 cm−1. The lipoamide showed higher antioxidant activity than ricinoleic acid based on the DPPH assay. The synthesized lipoamide exhibited weak antimicrobial activity against Staphylococcus aureus and Escherichia coli. [ABSTRACT FROM AUTHOR]

Chitin and chitosan, which due to their wide applicability and abundance are of increasing interest to industries. Chitin is extracted from a wide range of living things by a variety of methods, which may be chemical or biological. Chitosan is obtained from the alkaline deacetylation of chitin by chemical or enzymatic processes. Due to their different polysaccharide chains, chitin and chitosan have different properties. Chitin is thus an insoluble polymer in most solvents, while chitosan is a soluble polymer in acid solvents because there is protonation of the amide group of this polymer, which makes it soluble in acid solvents. The source from which the greatest extraction of chitin occurs is from crustaceans such as shrimps, crabs, lobsters, crayfish, and clams. Extraction from crustaceans is an economical process, but seasonal, since most crustaceans are species that only belong to one season of the year. Since crustaceans are living beings that are not in abundance in the environment and in all seasons of the year, insects have been the subject of study for the extraction of chitin, since they exist in abundance in nature, throughout the year and in various parts of the world, being an excellent resource for a large-scale production of chitin and chitosan. Chitosan is the base for bioplastics and membranes.in this work a review of the existing methods and applications will be surveyed. Also, some green metrics regarding the synthesis of chitosan will be presented and discussed. [ABSTRACT FROM AUTHOR]

Steroids are natural products of poly cyclic compounds and can be defined as bioactive substances. Thus, this article involves a synthesis of new derivatives from steroid analoge ((5-pregnen-3β,17β-diol-15α-yl)thio) propionate, amide and bi aryl compounds known for its biological activity, amide derivative 1 was prepared by treatment of steroid analoge with primary amine substituted in basic solution. Later, bi aryl compound 2-5 were synthesized via reacting 1 with boric acid derivatives by using Suzuki-Miyaura condition. Finally, all compounds characterization by spectral methods (FT-IR, 1H-NMR) and C.H.N analysis. [ABSTRACT FROM AUTHOR]

Oleamide is an alkylamide (fatty acid amide) that is synthesized from oleic acid and urea enzymatically using Candida rugosa lipase. The lipase is immobilized by entrapping method with chitosan matrix. One of the functions of oleamide is a surfactant. This study aimed to determine the optimum conditions for oleamide synthesis with reaction time and mole ratio parameters. Oleamide was synthesized from oleic acid with urea and was carried out by varying the reaction time at 6, 12, 24, 36, 48 hours and the mole ratio between oleic acid and urea at (1:1, 1:2, 1:3, 1:4, 1:5) with dichloromethane as solvent. The optimum conditions are indicated based on the highest conversion percentage that was calculated by the moles number of reacted oleic acid divided by the moles number of initial oleic acid. The oleic acid concentration was determined by alkali metric titration. The data of conversion percentage were statistically analyzed by one-way ANOVA followed by Tukey test. The resulting oleamide was identified using FTIR spectrophotometer and measured its HLB value. The result showed that reaction time and mole ratio had a significant effect on oleamide synthesis. The optimum conditions for oleamide synthesis occurred at 36 hours reaction time, and the moles ratio (1:5) resulted in 31.42±0.54% of the highest conversion percentage. Oleamide has been identified and characterized by FTIR spectrophotometer which showed absorption at wavenumbers 3226.09-3377.27 cm−1 (N-H), 2855.28-2926.59 cm−1 (C-H), 1655.83 cm−1 (C=O), and 1163.79 cm−1 (C-N). Oleamide has an HLB value of 5.64, which belong to a W/O emulsifier. [ABSTRACT FROM AUTHOR]

The purpose of this study was to observe the fatty acid amides (FAAs) profile synthesized from ketapang kernel oil (KKO) and urea as substrates. FFAs were synthesized by reacting KKO with urea in the presence of lipozyme (a commercial lipase from Rhizomucor miehei) as a catalyst. Identification of the product was observed by using thin-layer chromatography (TLC) and Fourier Transform Infrared Spectroscopy (FTIR). Meanwhile, the composition of the FFAs was analyzed by High-Performance Liquid Chromatography (HPLC). The HPLC parameters were mobile phase (acetonitrile: water) (90:10 v/v), 1,0 mL/min flow rate on 213 nm wavelength, and an injection volume sample of 20 µL. The result shows that the percentage yield of FFAs was 73-76%. FTIR spectra showed a typical absorption of wave numbers at 3423-3180, 1650-1632, and 1280-1175 cm−1, indicating N-H, C=O amide, and C-N bonds, respectively. The profile of FFAsindicated was linoleamide (39.97%), oleamide (32.80%), palmitamide (25.95%), and stearamide (1.28%). [ABSTRACT FROM AUTHOR]

The aim of this work is to study the condensation reaction of some aldehydes with amides - urea and thiourea, to create new means for the rubber industry based on local raw materials, to develop a highly efficient technology for their production. The reactions of condensation of formaldehyde aldehydes, acetic and crotonic aldehyde (croton fraction) with urea and thiourea are investigated. The technological parameters of the process were studied, it was found that the condensation of aldehydes with amines and amides first forms unstable amino alcohols - hydroxy derivatives of urea (thioureas), which, when heated, transform into imines and imides. Condensation of urea (thiourea) with the croton fraction occurs with the formation of a product of linear and cyclic structure. The resulting products were tested as an accelerator for vulcanization of rubbers, which are not inferior to an industrial reagent in their physical, mechanical and operational characteristics. [ABSTRACT FROM AUTHOR]

New tetrasubstituted thiacalix[4]arenes with amide and primary amino groups were synthesized in the cone and 1,3-alternate conformations, which were characterized by 1H, 13C NMR, IR spectroscopy and MALDI mass spectrometry. The obtained macrocycles can be used as building blocks for the synthesis of multifunctional compounds and the construction of transmembrane ion channels based on them. [ABSTRACT FROM AUTHOR]

Modification of monolayer graphene oxide (GO) was made using linear PEG method of PEG-NH2 amino group covalent coupling to GO surface carboxylic groups resulting in amide linkage formation. It was demonstrated that aromatic structure of initial GO did not change. Dimension of pegylated GO plates was changed in average size as compared to the initial one (1-5 mkm) lowering up to 569±14 nm. Amount of polyethylene glycol covering the GO was calculated as 19-20%. Technique has been developed to modify monolayer GO using linear polyethylene glycol and purposefully used it at differently sized GO. [ABSTRACT FROM AUTHOR]

Reactions of ethyl 2-tolylhydrazono-3-oxo-4,4,4-trifluorobutanoate with aqueous methylamine and ammonia resulted in the new amides of 2-tolylhydrazono-3-oxo-4,4,4-trifluorobutanoic acids. The study of their esterase profile and anti-scavenging activity showed that the obtained amides are effective free radical scavengers with rather weak inhibitory activity against carboxylesterase. [ABSTRACT FROM AUTHOR]

Today, destruction of various metal equipment is one of the most significant industrial problems. Nitrogen containing compounds, in particular, ammonium salts, are increasingly used for protection of oil pipeline equipment. Inhibitors based on organic compounds are of interest. The three-stage method of synthesis of hydrochloric corrosion inhibitors based on oleic acid amides has been developed. The reason of corrosion inhibition is an adsorption ability of organic surface-active compounds (SAC). It is connected with overlapping of the metal contact surface and the medium and the change in activation energy at free sites. The basis of developed inhibitors is the oleic acid (OA), an organic fatty compound with SAC properties. It is known that the content of nitrogen, sulfur and oxygen increases the protective ability. For this reason, several synthesis procedures were carried out with the purpose to increase its inhibiting properties. The substances were obtained in several stages. At the first stage, alkamines were added to the OA; then, the compounds obtained were sulfated with sulphuric acid. Reactions with alkali were carried out with the purpose to enhance the field of various inhibitors. As the result, salts of oleic acid amides, containing the sulfate group, were formed. With the purpose to establish efficiency of compounds obtained, assessment of protective capability in diluted hydrochloric acid was carried out. According to which, it was established that some of the substances obtained could be used as acid corrosion inhibitors. At this, the highest protective effect was demonstrated by sodium salts of target amides. Functional plots for approximation of the experimental data obtained with the logarithmic function were developed. Estimations were obtained. [ABSTRACT FROM AUTHOR]

The composition and structure of nitrogen-containing bases isolated from the maltene fraction of the liquid products of conversion of asphaltenes of bituminous oil from the Ashalchinskoye oilfield in a supercritical hexane stream at 450°C and 15 MPa are investigated. It is shown that they are represented by a mixture of high molecular weight and low molecular weight compounds, where high molecular weight components prevail. Compared to the initial asphaltenes, their mean molecules are characterized by smaller sizes associated with a decrease in the number of structural blocks (ma = 2.3 versus 3.4), in the composition of which the number of saturated cycles is significantly reduced (Rn* = 2.8 versus 6.0). The size of the aromatic core remains virtually unchanged. (Ra* = 2.9 versus 3.4). At the same time, the internal arrangement of aromatic cores in the naphthenoaromatic system of the structural block (Cα* = 4.5 and 5.6) is preserved, which causes a high degree of screening of the nitrogen atom and, as a consequence, thermal stability of the compounds. Using the GC–MS method, C2−C6 quinolines, C2−C4 benzoquinolines, C1 dibenzoquinolines, and C16H33NO, C18H35NO, C18H37NO aliphatic amides have been identified in the nitrogen-containing bases of maltenes. [ABSTRACT FROM AUTHOR]

We herein report the synthesis of a series of novel pharmacologically relevant coumarins linked with amides. The three-step methodology was found to be facile and compatible with a range of aryl and heteroaryl amines leading to the diverse arena of amides of considerable pharmacological relevance. [ABSTRACT FROM AUTHOR]

In this work, research on Physico-chemical characteristics of gelatin has been started with gelatin extraction using cow bone. Extracted gelatin has been characterized by Scanning Electron Microscopy-Energy Dispersive Analysis of X-rays (SEM-EDAX), thermal gravimetric analysis (TGA) Electrophoresis SDS-PAGE (sodium dodecyl sulfate-gel polyacrylamide) and Fourier Transform Infrared (FTIR) spectrophotometer. The characterization results showed that the extracted gelatin at optimum conditions had numerous of amine and amide as a functional group, a molecular weight at range closely from 90 until 110 kDa, a microstructure similar to tiny pipe with some stacking fault part, a carbon and nitrogen content of gelatin about 48 and 15%, respectively. From the physical-chemical properties of gelatin, it can be concluded that gelatin qualifies as a green template for nanomaterial production. It has been proofed by morphology observation of nanocarbon, carbon foam, spherical carbon, nano-silica and nano zinc oxide at previous work when using extracted gelatin for a template. The observation result during the synthesis process using gelatin as a green template showed that the interaction of the amine group in gelatin and precursor of nanomaterial a significant role during functional group rearrangement for nanosize material production. [ABSTRACT FROM AUTHOR]

This paper presents a new sensing material derived from carbon nanofibers (CNF) functionalized with carboxylic acid first, before further modified with amide functional group. This sensing material was used in the detection of ammonia gas at room temperature. Modified CNF was prepared via Fischer Esterification using dodecylamine as functionalizing reactant. The modified CNF was characterized by field emission-scanning electron microscopy attachment with energy dispersive X-ray (FESEM-EDX) analysis to confirm the attachment of carboxylic and amide functional group. Based on characterization result, CNF successfully modified with the carboxylic and amide functional group by exhibit alteration in their morphology and elemental composition. Then, modified CNF was deposited on interdigitated transducer (IDT) by drop casting method and placed in a customized chamber with electrical feed through occupied with outlet/inlet gas. The resistance of modified CNF upon injection of ammonia gas was monitored with a digital multimeter and compared with the resistance of pristine CNF. Based on the result, modified CNF showed a better response and higher sensitivity than pristine CNF at room temperature. [ABSTRACT FROM AUTHOR]

3-amino-5-(1H-indol-3-yl)-6-phenylpyrazine-2-carboxylic acid amides were obtained by the Taylor method, the SNH methodology, and further obtaining the amides through the corresponding acid chlorides. It is shown the formation of the unexpected product while using DCC. [ABSTRACT FROM AUTHOR]

Keratin modification on surface of titanium dioxide P25 was carried out from titanium dioxide suspension and keratin solution extracted from swine wool. The existence of amide component, protein functional groups dissociated to active protein moieties and attached to titanium dioxide surface in form of hybrid nanomaterial were characterized by Fourier-transform infrared spectroscopy (FT-IR). The keratin protein decorated on particle surfaces was observed by Field Emission Scanning Electron Microscopy (FESEM). Chemical states and bonding at the nano-biomolecule interfaces with titanium dioxide were investigated using X-ray Photoelectron Spectroscopy (XPS). Protein concentration is considered as roles for protein modification, surface bonding, chemical states and protein adsorption. The Ti3+ and Ti2+ surface and high adsorption degree can be obtained at low concentration of protein solution with P25. However, the strong bonding between protein and TiO2 obtained in high protein concentration with Ti3+ and Ti2+ species result disappear for Ti3+ and Ti2+ XPS peaks. The adsorbed protein reveals secondary structure of random coil keratin with strong bonding conjugated to the titanium dioxide surface. The strong binding between protein and TiO2 surface in this novel protein-TiO2 hybrid material shows a promising alternative way for advance tunable electronic structure and charge transport mechanism which enhance electrochemical capacitance by mean of double layer and pseudo-capacitive behavior. [ABSTRACT FROM AUTHOR]

In the present work, we performed a comparative investigation of smart window application of amide substituted thienylpyrrole derivatives. For this purpose two amide substituted thienylpyrrole derivatives were synthesized characterized and electrochemically polymerized. Characterizations of the resulting polymers were performed by cyclic voltammetry (CV), UV-vis spectroscopy. Moreover, the spectroelectrochemical, electrochromic properties and smart window applications of the polymer films were investigated. The resulting polymer films have distinct electrochromic properties. A smart window based on N-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)-4-(vinyloxy) benzamide (P(TPVB)), N1,N4-bis(2,5-di(thiophen-2- yl)-1H-pyrrol-1-yl)terephthalamide (P(BTPA)) and poly(3,4-ethylenedioxythiophene) (P(EDOT)) was set up in a sandwich configuration. The switching time and optical contrast (ΔT%) of the P(TPVB)/PEDOT and P(BTPA)/PEDOT devices at 625 and 621 nm are 1.0 s, 1.0 s and 43%,41 % respectively. [ABSTRACT FROM AUTHOR]

The effect of space holder amount and decomposition methods on the morphology, density and porosity and compressive properties of aluminum foams were investigated. Aluminum foam was fabricated by powder metallurgy method using spherical carbamide as space holder using three different decomposition method of carbamide includes; dissolution process, normal sintering process and two step sintering process. Aluminum foam with 60 wt.% carbamide has the lowest density and exhibited the highest porosity for all the decomposition. The results indicated that Al foams produced by dissolution method have the highest compressive properties with acceptable density and porosity value. [ABSTRACT FROM AUTHOR]

Dimer fatty acid polyamide nanocomposites based on flake- or needle-shaped nanoparticles were prepared via melt compounding. Transmission electron microscopy showed the presence of both individually dispersed particles and particle agglomerates in the polymer matrix. Dynamic mechanical analysis suggests that three stiffening mechanisms were operating. The reinforcing effect of the high stiffness inorganic filler particles is the primary contributor. Together with the chain confinement effect, that expresses itself in an apparent increase in the glass transition temperature, this provided an adequate rationalization of the stiffness variation below Tg. However, an additional stiffening effect is indicated at temperatures above Tg. The mechanism may involve dynamic network formation based on fluctuating hydrogen bonding interactions between the polymer chains and the filler particles. [ABSTRACT FROM AUTHOR]

The potential enhancement of the nanocomposite properties, with respect to the neat matrix, is strictly related to uniform distribution and dispersion of the nanofillers in the host polymer. In this work, two dispersant agents. particularly a polar wax and a silanol polyhedral oligomeric silsesquioxanes POSS, have been used in order to improve the dispersion of bare and functionalized carbon nanotubes in polyamide matrix. To ensure a good compatibility between matrix and nanofillers, the dispersing agents having specific polarity have been chosen, in order to match that of the matrix. Significant alterations of the mechanical and Theological behaviour due to dispersion action of used additives have been noticed and discussed, also considering the obtained morphology. [ABSTRACT FROM AUTHOR]

The importance and versatility of amide group containing ligands have promoted the selection of this class of ligands and their complexes for the study. The present work describes the synthesis, spectral and biological investigations on the complexes of amides derived from heterocyclic amines with Mn (II) ions. Four ligands derived 2-aminopyridine and their complexes with Mn (II) have been synthesized. A method for the synthesis of complexes has been developed by the use of microwave irradiation which is in agreement to Green chemistry approach. The complexes have been characterized on the basis of elemental analysis, infrared, electronic, ESR spectra and magnetic susceptibility studies. The diffuse reflectance spectrum of the complexes show bands in the region 20,000 cm-1 to 26,000 cm-1 assignable to 6A1g → 4T2g and 6A1g → 4E1g transitions. These are also typical of tetrahedral environment around the manganese. The magnetic moment (5.80 BM) of the complex indicates high spin tetrahedral environment. The microwave method of synthesis of complexes have been found easier, convenient and ecofriendly. Antimicrobial activities of compounds were also carried out against bacteria and fungi. Further minimal inhibitory concentration (MIC) was also determined for each compound. [ABSTRACT FROM AUTHOR]

In this study the effect of Ag Nano powder on mechanical properties of epoxy coatings filled with optimized ratio of conducting polymers (Polyaniline and Polyppyrole) was evaluated. Bisphenol A diglycidyl ether epoxy resin (DGEBA) along with polyaminoamide adduct (ARADUR 3282-1 BD) is used as curing agent under optimized stoichiometry values. Curing is performed at room temperature with different percentages of Nano filler. Glass and steel panels were used as coating substrate. Bird applicator was used to coat the samples in order to obtain thin film with wet film thickness (WFT) of about 70-90 ìm. The samples were kept in dust free environment for about 7 days at room temperature for complete curing. The coated steel panels were used to evaluate the mechanical properties of coating such as hardness, scratch and impact tests whereas coated glass panels were used for measuring pendulum hardness of the coatings. To check the dispersion and morphology of Nano filler in epoxy matrix scanning electron microscopy (SEM) was used in addition Nano indentation was also performed to observe the effect of Nano filler on modulus of elasticity and hardness at Nano scale. [ABSTRACT FROM AUTHOR]

The damping effect of the interaction of high-frequency amide-I vibrations with the low-frequency acoustic vibrations of the protein is investigated. The phenomena studied phenomonologically by extension of the nonlinear Schrodinger equation. By introducing a local approximation, the damping factor can be expressed as a new term iγφ in the nonlinear Schrodinger equation. The result show that the soliton with damping propagate slower than original one. By introducing a periodic external force, the equation of motion is described by the force-damped nonlinear Schrodinger equation. Solution based on the variational methods show that the Davidov's soliton will be accelerated by a periodic external force. [ABSTRACT FROM AUTHOR]

The geometric structures of the phenoxenium cation which is a cation intermediate of 2-azaspiro ring compounds (2-azaspiro[4.5]decane) from N-methoxy-N-prenylbenzamide are studied by means of the Hamiltonian algorithm with ab intio molecular orbital calculations at HF/3-21G level. The geometries are further refined with MP2/6-311G** level. We tried four substituted compounds with the methyl group. Among them only one compound with two methyl groups gives a ring-closure intermediate, which agrees well with the experimental results. [ABSTRACT FROM AUTHOR]

To clarify the effect of N-methylation to aromatic oligoamides on their conformations, we investigated Nmethylated aromatic amides theoretically, using the density functional theory calculations. It is well-known that Nmethylbenzanilide adopts a cis-conformation rather than a trans-conformation, in contrast to benzanilide. This is ascribed to large destabilization of trans-N-methylbenzanilide and large stabilization by the orbital interaction from nitrogen lone pair to anti-bondingπ* orbital of carbonyl group in cis-N-methylbenzanilide. N-methylated para-linked aromatic diamide has two preferable conformations and two of the conformations of the N-methylated para-linked aromatic oligoamidesexhibit two distinct helical structures. The potential for helix control by solvent is presented. [ABSTRACT FROM AUTHOR]

study on the hydration of nitriles to amides using 2,2,6,6-tetramethylpiperidin-l-ol and its derivatives in water has been carried out. Various nitriles including aromatic nitriles, heterocyclic nitriles and aliphatic nitriles were converted into the corresponding amides in good to excellent yields. Nitriles having electron-withdrawing groups could be converted into the corresponding amides in good yields at room temperature. 2,2,6,6-Tetramethylpiperidin-l-ol and its derivatives generated from the corresponding nitroxide free radicals and L-ascorbic acid in water were used for hydration reaction without separation leading to a simplification in the experiment. [ABSTRACT FROM AUTHOR]

Nanocomposite membranes based on multiwalled carbon nanotube /SPEEK (sulfonated poly ether ether ketone) have been synthesized via simple solution casting. Prior to use CNT have been purified and grafted with carboxylic acid groups onto its walls by means of sulfuric and nitric acid. Afterwards, amidation of carboxylated CNTs (c-CNT) has been done. Amidated CNT (a-CNT) is then incorporated in SPEEK polymer matrix to synthesize nanocomposite membranes. Physicochemical, structural, thermal and mechanical characterizations are done through the respective techniques. Electric and ionic conductivities have also been evaluated. Composites membranes show the enhanced electrochemical performance with higher electric conductivity. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the potential use of new synthetic biodegradable polyester amide drug-eluting fibrous membranes in skin wound treatment. The study fabricates the polyester amide fibrous membranes through electrospinning method in chloroform. It employs gallium nitrate as the incorporated therapeutic agent within electrospun PEA fibrous membranes.