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Amide functionalities present in living system as peptides and possess various biological role. Many synthetic amides also possess biological activities due to the possibility of interaction with cellular liquids such as those compounds useful as a contrast agent in radiographic method. Synthesis of amides from the carboxylic acid or derivatives normally require heating and catalyst. In this report, an environmentally benign synthesis of amide was carried out utilizing microwave radiation and catalyzed by imidazolium ionic liquids (BMIMCl). Microwave radiation provided efficient heating through activation of chemical bonds instead of conventional conductivity methods hence increasing the rate of reactions. Ionic liquids were suitable material in this synthesis due to non-volatile nature as well as stability under high temperature and microwave heating. Furthermore, ionic liquids are tunable material that can be designed for the specific synthesis and functioned as a catalyst. The optimum condition for coupling of 5-Amino-isophthalic acid dimethyl ester with an amino diol was found at 80 °C, 90 minutes, under radiation of microwave at the power of 300 Watt. The product was obtained at 38.46% yield. Furthermore, the methodology was applied to synthesis radiographic material and was successful to obtain product with 48.78% yield. The products were characterized by NMR spectroscopy.

Here we compare the host behaviour of two roof-shaped compounds, trans-9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboxylic acid H1 and its dimethyl ester, trans-dimethyl 9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboxylate H4, when presented with mixed xylene (o-Xy, m-Xy and p-Xy) and ethylbenzene (EB) guest solutions. Both host compounds formed complexes with all of these solvents, except H4/EB, where no inclusion occurred. When H1 was recrystallized from the various equimolar combinations of these guests, enhanced selectivities were observed for p-Xy. In fact, equimolar binary mixtures of o-Xy/p-Xy and m-Xy/p-Xy afforded complexes that showed near-complete host selectivity for p-Xy (96.6 and 93.6%, respectively). The selectivity displayed by H4 in analogous experimental conditions, however, was only ordinary at best. The complexes of H1 and H4 with p-Xy were explored in-depth by means of single crystal diffraction analyses. Owing to the scarcity in the number and type of host⋯guest interactions, both complexes may be defined as approaching that of true clathrates. Finally, data from thermoanalytical experiments concurred with the selectivity behaviour of both host compounds.

In water–DMF at DMF content less than 2.6 mol dm−3, deuteroporphyrin IX dimethyl ester forms both H- and J-aggregates. The J-aggregates are detected as a single type of associated species after binding of the porphyrin with BSA on the surface of the protein IB subdomain.

A new multicomponent reaction for regioselective synthesis of substituted 1,2,4-triazolo[1,5-a]pyrimidines using aminotriazoles, β-ketoglutaric acid dimethyl ester, and dimethylformamide dimethyl acetal was implemented. The selective reduction of 1,2,4-triazolo-[1,5-a]pyrimidines to dihydro derivatives and the use of triazolo pyrimidines as starting compounds in multicomponent synthesis of dihydropyrido[3,4-е][1,2,4]triazolo[1,5-a]pyrimidinecarboxylates was demonstrated.

In present study, multi-target and multi-pathway mechanisms of Jasminum lanceolarium Roxb (JL) on primary dysmenorrhea (PDM) treatment were predicted by the approach of network pharmacology and molecular docking, leading to the obtaining of 22 predicted targets for 69 compounds in JL. The Compound-Target analysis displayed intimate association among targets and compounds. Meanwhile, the Compound-Target-Target revealed PTGS2, OPRD1 and NOS3 were the key targets with intensive interaction. The Compound-Target-Pathway network indicated these pathways were closely related to hormone regulation, central analgesia, spasmolysis and inflammation. The anti-inflammation pathways might be the key mechanism of JL for the treatment of PDM based on KEGG pathway enrichment analysis and pharmacological experiment, and 10-hydroxyoleoside dimethyl ester might be a promising leading compound due to its good molecular docking scores and previous experimental evaluation.

The kinetics of the 2,5-dimethyl ester of furandicarboxylic acid transesterification in the presence of various catalysts at different temperatures was investigated. It was shown that the catalytic activity follows the order: Mn (OAc)2 < Co (OAc)2 < Zn (OAc)2 < Ti (OBu)4. The transesterification catalyzed by Ti (OBu)4 leads to the formation of the polymers with the higher molecular weight compared to Me (OAc)2.

Biopolyimides poly(ATA-CBDA) made from of 4,4′-diamino-α-truxillic acid dimethyl ester (ATA) and 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA) were synthesized and its electric volume resis...

Process parameters of the polymerization of a mixture of exo,exo- and endo,endo-dimethyl esters of norbornene-2,3-dicarboxylic acid in the bulk of the monomer under the action of a ruthenium catalyst of the Hoveyda–Grubbs type are developed. The effect of the concentration of the catalyst on the physical and mechanical properties of poly(norbornene-2,3-dicarboxylic acid dimethyl ester) is studied.

Novel plant growth regulators (PGRs) based on the derivatives of dehydroamino acids 2,3-dehydroaspartic acid dimethyl ester (PGR1), Z-isomer of the potassium salt of 2-amino-3-methoxycarbonylacrylic acid (PGR2) and 1-methyl-3-methylamino-maleimide (PGR3) have been synthesized and their growth-regulating properties investigated. Laboratory testing revealed their plant growth-regulating activity. PGR1 showing the most stimulating activity on all laboratory tested cultures were used in field experiments. Results showed that PGR1 is a highly effective environmentally friendly plant growth regulator with effects on different crops. Biopolymeric microcapsule formulations (chitosan/alginate microcapsule loaded with PGR) suitable for application in agriculture were prepared and characterized. Physicochemical properties and release profiles of PGRs from microcapsule formulations depend on the molecular interactions between microcapsule constituents including mainly electrostatic interactions and hydrogen bonds. The differences in the microcapsule formulations structure did not affect the mechanism of PGRs release which was identified as diffusion through microcapsules. The obtained results opened a perspective for the future use of microcapsule formulations as new promising agroformulations with a sustained and target release for plant growth regulation.

For the preparation of compound libraries of Michael acceptors with tunable reactivity toward nuclophilic selenocysteine residue of thioredoxin reductase, a range of 3-arylglutaconic acids were required. The existing methods at the time had limited scope or involved several steps. A hitherto undescribed protocol for direct palladium(II) acetate-catalyzed arylation of glutaconic acid dimethyl ester at position 3 has been developed with a diverse set of arenediazonium tosylates followed by hydrolysis. This generally good-yielding two-step sequence displayed a propensity to deliver E-configured coupling products while compounds mostly featured in the literature were predominantly Z-configured. The possibility for preparing a library of 4-arylpyridine-2,6(1H,3H)-diones has been exemplified.

To explore the influence of a biologically inspired second and outer coordination sphere on Rh-bis(diphosphine) CO2 hydrogenation catalysts, a series of five complexes were prepared by varying the substituents on the pendant amine in the P(Et)2CH2NRCH2P(Et)2 ligands (PEtNRPEt), where R consists of methyl ester modified amino acids, including three neutral (glycine methyl ester (GlyOMe), leucine methyl ester (LeuOMe), and phenylalanine methyl ester (PheOMe)), one acidic (aspartic acid dimethyl ester (AspOMe)) and one basic (histidine methyl ester (MeHisOMe)) amino acid esters. The turnover frequencies (TOFs) for CO2 hydrogenation for each of these complexes were compared to those of the non-amino acid containing [Rh(depp)2]+ (depp) and [Rh(PEtNMePEt)2]+ (NMe) complexes. Each complex is catalytically active for CO2 hydrogenation to formate under mild conditions in THF. Catalytic activity spanned a factor of four, with the most active species being the NMe catalyst, while the slowest were the GlyOMe and the AspOMe complexes. When compared to a similar set of catalysts with phenyl-substituted phosphorous groups, a clear contribution of the outer coordination sphere is seen for this family of CO2 hydrogenation catalysts.

An optimized method for (2R,3S)-isocitric acid lactone-2,3-dicarboxylic acid dimethyl ester as an (2R,3S)-isocitric acid building block based on a fermentation solution containing both (2R,3S)-isocitric acid (ICIT) and citric acid is described. The number of operations needed until now has been reduced; some steps have been modified, making altogether the method distinctly faster. During the course of this investigation, crystal structures have been determined of (2R,3S)-isocitric acid lactone-2,3-dicarboxylic acid dimethyl ester, (2R,3S)-isocitric acid lactone-2,3-dicarboxylic acid, and (2R,3S)-isocitric acid lactone-2,3-dicarboxylic acid anhydride. For the first time, full NMR data are given for ICIT trimethyl ester and ICIT lactone-2,3-dicarboxylic acid dimethyl ester. The multigram amounts of the three ICIT lactone compounds open the way for the synthetic use of ICIT generated in a biotechnological process.

Made available in DSpace on 2019-10-04T12:36:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-03-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae) has developed resistance to numerous conventional insecticides, which has led us to investigate the toxicity of ten dihydrobenzofuran- (DBN) and benzofuran-type (BN) neolignans structurally related to conocarpan against second instar B. tabaci nymphs. At concentrations higher than 5mg/L, most of the tested compounds killed 100% of B. tabaci biotype B nymphs 6days after spraying. The contact toxicity of compounds 2 ((+/-)-trans-dehydrodiferulate dimethyl ester), 3 ((+/-)-4-O-methyl-trans-dehydrodiferulate dimethyl ester), 5 ((+/-)-4-O-acetyl-trans-dehydrodiferulate dimethyl ester), 6 ((+/-)-7,8-dihydro-trans-dehydrodicoumarate dimethyl ester), 8 ((+/-)-4-O-methyl-7,8-dihydro-trans-dehydrodiferulate dimethyl ester), and 10 ((+/-)-7,8-dihydro-7,8-dehydro-trans-dehydrodicoumarate dimethyl ester) was higher than the contact toxicity of pyriproxyfen at a concentration of 75mg/L, which was used as positive control. Repellent (compounds 2 and 7 ((+/-)-7,8-dihydro-trans-dehydrodiferulate dimethyl ester) and oviposition deterrent (compounds 2, 3, and 7) effects were observed for adult whiteflies exposed to leaves sprayed with DBNs for 24 and 48h, respectively. These results suggest that DBNs have potential application in the development of effective pest management compounds. Univ Estadual Paulista, Fac Ciencias Agron Botucatu, Dept Protecao Vegetal, Botucatu, SP, Brazil Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, Ribeirao Preto, SP, Brazil Univ Estadual Paulista, Fac Ciencias Agron Botucatu, Dept Protecao Vegetal, Botucatu, SP, Brazil FAPESP: 2013/20094-0 FAPESP: 2016/16957-0

During the course of our studies toward the total synthesis of nigricanoside A dimethyl ester, a prototype method for the connection of the left- and right-half segments at the C9′–C10′ double bond was developed using a model system. The method was based on a simple three-step process including: (i) a nitroaldol reaction, (ii) chlorination or thionocarbonylation, and (iii) radical elimination.

The synthesis of a potential immunosuppressant, i.e. dimethyl ester of N-mycophenoyl malonic acid was optimized in the reaction of mycophenolic acid (MPA) with amino malonic dimethyl ester in the presence of propanephosphonic anhydride (T3P) as a coupling reagent. The structural properties of the obtained MPA derivative were investigated by NMR, MS and single crystal X-ray diffraction methods. Theoretical considerations of conformational flexibility based on DFT calculations are presented.

The molluscicidal effect of the aqueous extract of Thymus vulgaris (thyme) on the land snail Eobanica vermiculate was tested. Snails showed morphological alterations, such as swollen of the snail body due to water retention, which led to slow motion of snails, protrude of tentacles and foot due to their enlargement. Abnormal bully-like structure appeared at the head region (a swollen part of the skin filled with aqueous material). Samples of the integument, bully-like structure, mantle edge, digestive gland and gonads were dissected out and prepared for histological examination under light microscope. Some morphological tissue abnormalities were recorded. The highest mortality rate (83.3%) was recorded at concentration 12.5%. The estimated LC30,LC50 and LC90 were 5.832, 8.029 and 13.398 respectively. The plant extract used was chemically analyzed by high performance liquid chromatography (HPLC) to determine its active ingredients. The first five ingredients that have the highest concentrations were 2-Bromo dodecane, 3-methylindole, n-Tricosane, Octadecanedioic acid and Tetradecanedioic acid dimethyl ester.