Aliphatic Acetates Research Articles

Binding Interaction Between Lauric Acid and Cluster of Differentiation 36 Underpinned by a Fluorescence- Intensifying Assay.

Cluster of differentiation 36 (CD36) is a scavenger receptor expressed in various vertebrate cells that contains diverse ligands, including long-chain fatty acids. This receptor has recently been suggested as a captor of specific volatile odorants (e.g., aliphatic acetates) in the mammalian nasal epithelium. This study used a fluorescence-intensifying assay to produce the first evidence that lauric acid, an odorous fatty acid, directly binds to CD36. This expansion of the repertoire of volatile ligands supports potential applications for nasal CD36. Our present findings could promote future research aimed at understanding the mechanisms of fatty acid interactions with CD36.

Potential of Cinnamomum iners wood as antimicrobial agent

The wood of Cinnamomum iners (Medang Teja) believe in giving multiple beneficial, especially in traditional usage. However, due to the lack of studies regarding this species made this species unable to express its full potential being commercialised by the industry. Thus, this study is prosecuted with the objectives to evaluate the chemical composition and analyse the biological activity of extractive and essential oil derived from Cinnamomum iners (Medang Teja) wood. The samples that evaluated comprises of 100%, 1%, 2%, 3% essential oils and extractive of chemical composition are conducted through Fourier Transform Infrared Spectroscopy (FTIR) and Gas-Chromatography Mass Spectrometry (GCMS) analysis. Meanwhile analysing of its biological activity is made through antifungal and antimicrobial activity. The results found that the functional group presents in all the samples shared one similar functional groups which are aliphatic hydrocarbons. For 100% essential oil, the functional groups are aliphatic propionate ester, aliphatic hydrocarbons and tertiary aliphatic alcohols. 1%, 2%, and 3% essential oil consist of the same functional groups which are olefins, aliphatic hydrocarbons and aliphatic acetate esters. Extractives have aliphatic hydrocarbons and primary aliphatic alcohols. Through GCMS, the major compounds found in the samples are 2(1H)-Naphthalenone, octahydro-, trans-Linalool,. beta. Fenchyl alcohol, Camphor, Benzene, ethyl-(CAS) EB. The similar compound found in all samples are Linalool, terpinene-4-ol, Terpineol, Copaene, Cadinene. From the antifungal analysis, it is proved that all of the samples can hold the antifungal traits, as all the samples show the effects of inhibitory on both brown-rot, Coniophora puteana and white-rot fungi, Pycnoporus sanguineus. The most susceptible organisms are the Coniophora puteana which showed a lower average diameter of inhibition zone for all the sample. Lastly, the samples shown a positive result in being antimicrobial agents for both gram negative, Escherichia coli and gram positive, Staphylococcus aureus.

Scientific Opinion on Flavouring Group Evaluation 61 Revision 2 (FGE.61Rev2): consideration of aliphatic acetals evaluated by JECFA (57th, 63rd and 68th meetings) structurally related to acetals evaluated by EFSA in FGE.03Rev2.

The EFSA Panel on Food Additives and Flavourings was requested to evaluate 12 flavouring substances attributed to the Flavouring Group Evaluation 61 (FGE.61), using the Procedure as outlined in the Commission Regulation (EC) No 1565/2000. Nine substances have already been considered in FGE.61 and FGE.61Rev1 [FL‐no: 06.001, 06.004, 06.005, 06.008, 06.009, 06.015, 06.028, 06.037, 06.081]. The remaining three substances [FL‐no: 06.025, 06.031 and 06.072] have been cleared with respect to genotoxicity in FGE.200Rev1 and are considered in this revision 2 of FGE.61. The substances were evaluated through a stepwise approach that integrates information on the structure–activity relationships, intake from current uses, toxicological threshold of concern (TTC), and available data on metabolism and toxicity. The Panel concluded that none of the 12 substances gives rise to safety concerns at their levels of dietary intake, estimated on the basis of the ‘Maximised Survey‐derived Daily Intake’ (MSDI) approach. Besides the safety assessment of the flavouring substances, the specifications for the materials of commerce have also been considered and found adequate. For nine flavouring substances [FL‐no: 06.001, 06.004, 06.005, 06.008, 06.009, 06.015, 06.028, 06.037 and 06.081], use levels are still needed to calculate the modified Theoretical Added Maximum Daily Intake (mTAMDI) values in order to identify those flavouring substances that need more refined exposure assessment and to finalise the evaluation accordingly.

Practical Cleavage of Acetals by Using an Odorless Thiol Immobilized on Silica

A practical, efficient and general method was developed for the deprotection of a variety of aromatic and aliphatic acetals to their corresponding catechol or diol derivatives using thiol immobilized on silica gel. This is an application for the well‐known commercial solid‐supported thiol (SiliaMetS® Thiol). The procedure is mild and amenable to scale‐up. It does not require inert atmosphere and clean conversions were observed. This method is applicable to substituted 1,3‐benzodioxole and aliphatic acetals with different functionalities. It offers the advantage of a general route with high yield, which can be undertaken at ambient temperature.

Prediction of Interactions between Binary Mixtures of Aliphatic Amines and Aliphatic Acetates

Prediction of Interactions between Binary Mixtures of Aliphatic Amines and Aliphatic Acetates

Antennal olfactory responses of adult meadow spittlebug, Philaenus spumarius, to volatile organic compounds (VOCs).

The meadow spittlebug, Philaenus spumarius L. (Hemiptera, Aphrophoridae) is a commonly found vector of Xylella fastidiosa Wells et al. (1987) strain subspecies pauca associated with the “Olive Quick Decline Syndrome” in Italy. To contribute to the knowledge of the adult P. spumarius chemoreceptivity, electroantennographic (EAG) responses of both sexes to 50 volatile organic compounds (VOCs) including aliphatic aldehydes, alcohols, esters, and ketones, terpenoids, and aromatics were recorded. Measurable EAG responses were elicited by all compounds tested. In both sexes, octanal, 2-octanol, 2-decanone, (E)-2-hexenyl acetate, and vanillin elicited the strongest antennal amplitude within the chemical groups of aliphatic saturated aldehydes, aliphatic alcohols, aliphatic acetates and aromatics, respectively. Male and female EAG responses to sulcatol, (±)linalool, and sulcatone were higher than those to other terpenoinds. In both sexes, the weakest antennal stimulants were phenethyl alcohol and 2-pentanone. Sexual differences in the EAG amplitude were found only for four of test compounds suggesting a general similarity between males and females in antennal sensitivity. The olfactory system of both sexes proved to be sensitive to changes in stimulus concentration, carbon chain length, and compound structure. Compounds with short carbon chain length (C5—C6) elicited lower EAG amplitudes than compounds with higher carbon chain length (C9—C10) in all classes of aliphatic hydrocarbons with different functional groups. The elucidation of the sensitivity profile of P. spumarius to a variety of VOCs provides a basis for future identification of behaviorally-active compounds useful for developing semiochemical-based control strategies of this pest.

Metal ion hydrocarbon bidentate bonding in alkyl acetates, methyl alkanoates, alcohols and 1-alkenes: a comparative study.

The relative affinity of the monovalent metal ions Li+, Na+, Cu+ and Ag+ towards a series of aliphatic alkyl acetates and some selected 1-alkenes (P) was examined using the kinetic method. A detailed analysis of the dissociation characteristics of a series of mixed metal-bound dimer ions of the type P1-M+-P2 and the evaluated proton affinities (PAs) of the monomers shows that the affinity of the cation towards long-chain alkyl acetates and alkenes (having a chain length ≤ C4) is markedly enhanced. In line with recent studies of nitriles, alcohols and methyl alkanoates, this is attributed to a bidentate interaction of the metal ion with the functional group or double bond and the aliphatic chain. In particular, the longer chain alkyl acetates, methyl alkanoates and alcohols show a remarkably similar behaviour with respect to silver ion hydrocarbon bonding. The Ag+ adducts of the alkyl acetates dissociate by loss of CH3COOH. This reaction becomes more pronounced at longer chain lengths, which points to metal ion bidentate formation in [Ag+···1-alkene] product ions having a long hydrocarbon chain. In the same vein, the heterodimers [1- hexene···Ag+···1-heptene] and [1- heptene···Ag+···1-octene] dissociate primarily into [Ag+···1-heptene] and [Ag+···1-octene] ions, respectively. Hydrocarbon bidentate formation in [Ag+···1-octene] also reveals itself by the reluctance of this ion to react with water in an ion trap, as opposed to [Ag+···1-hexene] which readily undergoes hydration.

Palladium on Carbon-Catalyzed Chemoselective Oxygen Oxidation of Aromatic Acetals

The development of an unprecedented chemoselective transformation has contributed to forming a novel synthetic process for target molecules. Chemoselective oxidation of aromatic acetals has been accomplished using a reusable palladium on carbon catalyst under atmospheric oxygen conditions to form ester derivatives with tolerance of aliphatic acetals and ketals.

Structure and internal dynamics of n-propyl acetate studied by microwave spectroscopy and quantum chemistry

The gas phase structure of n-propyl acetate was determined using molecular beam Fourier transform microwave spectroscopy from 2 to 40GHzsupplemented by quantum chemical calculations. The experimental spectrum revealed only one conformer with trans configuration and C1 symmetry. Torsional splittings occurred for each rotational transition due to the internal rotation of the acetyl methyl group with a barrier height of approximately 100cm−1. The XIAM and BELGI-C1 codes were applied to reproduce the spectrum within the measurement accuracy. This investigation on n-propyl acetate has accomplished our studies on saturated linear aliphatic acetates CH3COOCnH2n+1 (n=1–6).

Density functional theory study of selective deacylation of aromatic acetate in the presence of aliphatic acetate under ammonium acetate mediated conditions.

Aromatic acetates can be selectively deprotected in the presence of aliphatic acetates under ammonium acetate mediated condition. B3LYP/6-31++G** level of theory was demonstrated to be successfully used to model the relative reaction rates for deacylation reactions for aliphatic and aromatic ester systems. On the basis of the mechanistic studies, acetate anion is most likely to be the active catalyst for the ester deacylation reactions under ammonium acetate mediated condition.

ChemInform Abstract: Environmentally Benign Metal Triflate‐Catalyzed Reductive Cleavage of the C—O Bond of Acetals to Ethers.

AbstractA mild and efficient protocol for the cleavage of the C‐O bonds of aromatic and aliphatic acetals to ethers without affecting aromatic rings, nitro, nitrile, ester, and hydroxyl groups is reported.

Base Catalyzed Glycerolysis of Ethyl Acetate

Glycerol is a simple polyol compound widely used as a green solvent, having backbone to all lipids known as triglycerides. In our present study, we used glycerol as an acyl acceptor for transesterification of aliphatic acetate by conventional and using microwave assisted synthesis. It was found that increase in the concentration of substrate and catalysts with reaction time, increases yield of aliphatic alcohols. The reaction was followed by separation of product from glycerol by simple extraction with diethyl ether and studied for their HPLC and GC analysis.

Environmentally benign metal triflate-catalyzed reductive cleavage of the C–O bond of acetals to ethers

A protocol is described for the reductive cleavage of the C–O bond of aromatic and aliphatic acetals to ethers catalyzed by Cu(OTf)2 or Bi(OTf)3 at room temperature in excellent yields, without affecting aromatic rings, nitro, nitrile, ester and hydroxyl groups. This protocol represents an improvement in terms of atom economy compared to the previous methods, by distinctly decreasing the amount of the reducing reagent, 1,1,3,3-tetramethyldisiloxane (TMDS), and using a small amount of catalyst.

New Platinum‐Catalysed Dihydroalkoxylation of Allenes

AbstractA new platinum‐catalysed dihydroalkoxylation of allenes is described to give aliphatic acetals by an unexpected attack of two molecules of methanol to the terminal carbon of the allene moiety. Deuteration experiments suggest an unprecedented formal 1,3‐dipolar addition of methanol to a zwitterionic platinum carbene as the key step. The first platinum‐catalysed intermolecular carbon‐based nucleophile addition to allenes is also reported.

Flavouring Group Evaluation 61, Revision 1 (FGE.61Rev1): Consideration of aliphatic acetals evaluated by JECFA (57th meeting) structurally related to acetals of branched- and straight-chain aliphatic saturated primary alcohols and branched- and straight-c

Flavouring Group Evaluation 61, Revision 1 (FGE.61Rev1): Consideration of aliphatic acetals evaluated by JECFA (57th meeting) structurally related to acetals of branched- and straight-chain aliphatic saturated primary alcohols and branched- and straight-c

Highly atom efficient aluminium triflate catalysed acetal formation

Aromatic and aliphatic acetals are formed in excellent yields under solventless conditions at room temperature within 30 minutes by treating aldehydes and ketones with 0.5 mol% Al(OTf)3 as a recyclable catalyst in the presence of only 1.2 equivalents of an orthoester as reagent.

Development of PVC-resin-controlled release formulation for pheromones and use in mating disruption of yellow rice stem borer, Scirpophaga incertulas

Half lives of a range of Lepidopteran sex pheromone components incorporated into plasticized polyvinylchloride (PVC)-resin formulations were determined under a range of conditions in a laboratory wind tunnel and in the field in Egypt, Pakistan and India. Increasing aliphatic chain length by two methylene groups increased half lives by a factor of approximately 7.5 at 27 °C. Half lives of saturated aliphatic acetates decreased with increase in temperature by 79.2%, 85.5% and 95% for dodecyl acetate, tetradecyl acetate and hexadecyl acetate, respectively, between 22 and 34 °C. Addition of the polymer-soluble dye, Waxoline Black, improved the stability of labile aldehydes and polyunsaturated compounds incorporated into plasticized PVC under field conditions, although the antioxidant BHT had no effect. Studies confirmed that the formulation was ideally suited for the release of 14-carbon acetates and 16-carbon aldehydes with typical field lives of 70–100 days. A PVC-resin formulation of sex pheromone was tested for mating disruption of yellow rice stem borer, Scirpophaga incertulas, in replicated 1 ha plots in India over two seasons. Even at an application rate of 10 g a.i./ha/season there was a significant reduction in damage relative to that in plots treated with insecticides. However, application rates of 30–40 g a.i./ha/season are recommended for general use by farmers.

A novel application of tin-based alkoxide anion for deacetylation

A stannylene acetal, in the presence of CsF, is able to cleave both aromatic and aliphatic acetates rapidly and efficiently under room temperature. Control experiments indicate that both the stannylene acetal and CsF are required and play significant roles in the deacetylation process. Thus, it is likely that the tin-based alkoxide anion generated by a stannylene acetal and CsF is responsible for deacetylation.

Efficient Brønsted Acid Catalyzed Hosomi-Sakurai Reaction of Acetals

Acetals react with allyltrimethylsilane in the presence of a catalytic amount of sulfonic acids to give the corresponding homoallylic ethers in high yields. The scope of the reaction is broad and both aromatic as well as aliphatic acetals can readily be used.

Indium(III) triflate catalyzed tandem azidation/1,3-dipolar cycloaddition reaction of ω,ω-dialkoxyalkyne derivatives with trimethylsilyl azide

The azidation reaction of dialkyl acetal derivatives with trimethylsilyl azide (TMSN 3) was efficiently catalyzed by 1–5 mol % of In(OTf) 3. The major product differed depending on the substrate structure and molar ratio of TMSN 3, that is, aliphatic acetals provided α-azido ether derivatives, while aromatic acetal (benzaldehyde dimethyl acetal) provided gem-diazide, respectively. Furthermore, novel tandem azidation/1,3-dipolar cycloaddition reaction using alkynyl acetal derivatives gave bicyclic triazolo-heterocyclic compounds, recognized as chemically modified aza-sugar analogues, in high yields under mild conditions.