Teores de compostos orgânicos em cachaças produzidas na região norte fluminense - Rio de Janeiro

This work aimed to quantify some organic compounds in "cachaças" (sugar cane spirit). The ethyl alcohol was quantified by densimetry, after distillation. The acetic acid, methyl alcohol, n-propyl alcohol, n-butyl alcohol, isobutyl alcohol, isoamyl alcohol (mixture of 2-methyl-butyl and 3-methyl-butyl), ethyl acetate and acetaldehyde were determined by gas chromatography; and the furfural, 5-hydroxy-methylfurfural and acrolein by high efficiency liquid chromatography. From the 30 samples analyzed, 63.3% showed non-conformity with national legislation regarding at least one of the analyzed components.

Síntese de novas amidas graxas a partir da aminólise de ésteres metílicos

Recent biochemical and pharmacological studies have led to the characterization of different fatty acid amides as a new family of biologically active lipids. Here, we describe the synthesis of new amides from C16:0, 18:0, 18:1 and 18:1, OH fatty acids (FFA) families with cyclic and acyclic amines and demonstrate for the first time that these compounds produce citotoxic effects. Application of this method to the synthesis of fatty acid amides was performed using the esters aminolysis as a key step and various carboxylic amides were prepared in good yield from fatty acid methyl esters (FAMEs).

Synthesis and biological activity of n-{5-(4-methylphenyl) diazenyl-4-phenyl-1, 3-thiazol-2-yl}benzamide derivatives

In the present study, various amides of 2-amino-5-(4-methylphenyl)-diazenyl-4-phenyl-1, 3-thiazole was synthesized and their biological activities were evaluated. All the synthesized compounds were characterized by the combination of elemental analysis and standard spectroscopic methods. They are screened for anti-bacterial activity against Escherichia coli and Staphylococcus aureus as well as screened for antifungal activity against Aspergillus niger and Apergillus oryzae by cup plate method at 1 µg/ mL concentration in DMF.

Resolução do ibuprofeno: um projeto para disciplina de química orgânica experimental

A practical and didactic sequence of experiments was proposed to illustrate the stereochemistry concept, optically active compounds, resolution of racemates, and use of the NMR technique, including 2D-COSY for identification of organic compounds, on a laboratory course for undergraduate students. The sequence was: extractions of racemic ibuprofen and chiral naproxen from commercial tablets; syntheses of diastereoisomeric amides reacting chiral (S)-(-)-α-methylbenzylamine with (±)-ibuprofen; separation and determination of absolute configuration of amides by ¹H NMR spectroscopy and GC analysis, and hydrolysis of amides to obtain (+)- and (-)-ibuprofen.

Novas N-benzoiltiraminas de Swinglea glutinosa (Rutaceae)

Phytochemical studies of the leaves and fruits have led to the identification of the known amides (E)-N-methyl-cinnamamide, N-benzoyltyramine, N-benzoyl-O-geranyltyramine, N-benzoyl-O-(4-acetoxyl)-geranyltyramine, in addition to the new N-{2-[4-(butoxyl-3-one)phenyl]ethyl}benzamide, N-{2-[4-(2,3-dihydroxy-2-methyl-butoxylanal)phenyl]ethyl}benzamide, N-{2-[4-(2,3-dihydroxy-2-methyl-butoxyloic)phenyl]ethyl}benzamide, N-benzoyl-O-(4-acetoxyl-6,7-epoxy)-geranyltyramine, N-benzoyl-O-(4-acetoxyl-6,7-dihydroxy)-geranyltyramine and N-benzoyl-O-(6-acetoxyl-4,7-dihydroxy)-geranyltyramine. The isolated compounds clearly point to Swinglea phytochemical affinities with other Aurantioideae species.

Constituintes químicos de Solanum buddleifolium Sendtn

The chemical investigation of the stem EtOH extract of S. buddleifolium resulted in the isolation of terpenoids, amides, lignans and a steroidal alkaloid. Based on HRMS, IR and ¹H and 13C NMR data analysis, the structures of the isolated compounds were identified as: 13-hydroxysolavetivone, betulinic acid, N-trans-caffeoyltyramine, N-trans-feruloyldopamine, N-trans-p-cumaroyltyramine, N-trans-feruloyltyramine, N-trans-feruloyl3'-O-methoxydopamine, alangilignoside C, isolariciresinol, polistachiol, (+)-(8R,7'S,8'S)-3α-O-(β-D-glucopiranosyl)-lioniresinol, (-)-(8S,7'R,8'R)-3α-O-(β-D-glucopiranosyl)-lioniresinol and solamargine. The occurrence of terpenoids and amides is common in Solanum, unlike lignans which are rare. The isolated lignans described in this work are reported for the first time in the genus Solanum.

Otimização da etapa de extração do ácido clavulânico presente no caldo de fermentação utilizando misturas de solventes

The purpose of this work was to study four different solvent mixtures intended to increase the yield of the extraction stage of clavulanic acid (CA), which is one of the steps in the purification process. Four central composite rotatable designs (CCRD) were utilized to optimize the solvent mixtures. The variables selected for the factorial design were solvent mixture ratio (mL/mL) and temperature (ºC). The results showed that the yield of CA extracted from fermentation broth with the solvent mixtures of methyl-ethyl-ketone and ethyl acetate, and methyl-isobutyl-ketone and ethyl acetate (44.7 and 50.0%, respectively) was higher than that of the individual ethyl acetate alone (36.5%).

Regioselective modification of galactose-containing polysaccharides in aqueous media

Biorefining is defined as sustainable conversion of biomass into marketable products and energy. Forests cover almost one third of earth’s land area, and account for approximately 40% of the total annual biomass production. In forest biorefining, the wood components are, in addition to the traditional paper and board products, converted into chemicals and biofuels. The major components in wood are cellulose, hemicelluloses, and lignin. The main hemicellulose in softwoods, which are of interest especially for the Nordic forest industry, is O-acetyl galactoglucomannan (GGM). GGM can be isolated in industrial scale from the waste waters of the mechanical pulping process, but is not yet today industrially utilized. In order to attain desired properties of GGM for specific end-uses, chemical and enzymatic modifications can be performed. Regioselective modifications of GGM, and other galactose-containing polysaccharides were done by oxidations, and by combining oxidations with subsequent derivatizations of the formed carbonyl or carboxyl groups. Two different pathways were investigated: activation of the C-6 positions in different sugar units by TEMPO-mediated oxidation, and activation of C-6 position in only galactose-units by oxidation catalyzed by the enzyme galactose oxidase. The activated sites were further selectively derivatized; TEMPO-oxidized GGM by a carbodiimide-mediated reaction forming amides, and GO-oxidized GGM by indium-mediated allylation introducing double or triple bonds to the molecule. In order to better understand the reaction, and to develop a MALDI-TOF-MS method for characterization of regioselectively allylated GGM, α-D-galactopyranoside and raffinose were used as model compounds. All reactions were done in aqueous media. To investigate the applicability of the modified polysaccharides for, e.g., cellulose surface functionalization, their sorption onto pulp fibres was studied. Carboxylation affects the sorption tendency significantly; a higher degree of oxidation leads to lower sorption. By controlling the degree of oxidation of the polysaccharides and the ionic strength of the sorption media, high degrees of sorption of carboxylated polysaccharides onto cellulose could, however, be obtained. Anionic polysaccharides were used as templates during laccase-catalyzed polymerization of aniline, offering a green, chemo-enzymatic route for synthesis of conducting polyaniline (PANI) composite materials. Different polysaccharide templates, such as, native GGM, TEMPO-oxidized GGM, naturally anionic κ-carrageenan, and nanofibrillated cellulose produced by TEMPO-oxidation, were assessed. The conductivity of the synthesized polysaccharide/PANI biocomposites varies depending on the polysaccharide template; κ-CGN, the anionic polysaccharide with the lowest pKa value, produces the polysaccharide/PANI biocomposites with the highest conductivity. The presented derivatization, sorption, and polymerization procedures open new application windows for polysaccharides, such as spruce GGM. The modified polysaccharides and the conducting biocomposites produced provide potential applications in biosensors, electronic devices, and tissue engineering.

Determination of decomposition products of flotation collector chemicals using capillary electrophoresis

Vaahdotusta käytetään yleisesti erottamaan eri mineraaleja malmista. Tässä menetelmässä käytetään erityisiä pinta-aktiivisia aineita, joita kutsutaan kokoojakemikaaleiksi, muuntamaan halutut mineraalit hydrofobisiksi ja erottamaan ne hydrofiilisistä partikkeleista ilmakuplien avulla. Eräs tärkeimmistä kokoojakemikaalien ryhmistä on ksantaatit. Ksantaateilla on havaittu taipumusta hajota useiksi erilaisiksi hajoamistuotteiksi vaahdotusprosessin aikana. Näillä hajoamistuotteilla voi olla monia haitallisia vaikutuksia vaahdotuksen tuloksiin. Näiden tuotteiden tunnistaminen ja määrittäminen on tärkeää vaahdotusprosessin paremman ymmärtämisen kannalta. Työn kirjallisuusosassa vaahdotusprosessi, ksantaatit ja niiden yleisimmät hajoamistuotteet on esitelty, kuten myös käytetty analyysimenetelmä, kapillaarielektroforeesi. Työn kokeellisessa osassa etsittiin sopivaa erotusmenetelmää etyyliksantaatin, etyylitiokarbonaatin, etyyliperksantaatin ja etyyliksantyylitiosulfaatin erottamiseksi kapillaarilelektroforeesilla. Pääasiassa keskityttiin kahteen eri erotusmenetelmään. Ensimmäinen menetelmä kykeni erottamaan kaikki tutkitut tuotteet puhdasvesinäytteissä, ja toinen menetelmä oli sopiva näiden tuotteiden erottamiseen prosessivesinäytteissä. Jälkimmäistä menetelmää kokeiltiin käytännössä rikastamolla, jossa sillä kyettiin erottamaan isobutyyliksantaatti, isobutyylitiokarbonaatti, ja suurella todennäköisyydellä myös isobutyyliperksantaatti.

Determination of collector chemicals from flotation process waters using capillary electrophoresis

Vaahdotusprosessia käytetään yleisesti erottamaan arvokkaita mineraaleja malmeista. Toimiakseen tehokkaasti prosessi tarvitsee kokoojakemikaaleja, joiden tehtävänä on sitoa halutut mineraalit ilmakupliin. Jotta näiden kemikaalien käyttäytymistä prosessissa voitaisiin ymmärtää paremmin ja prosessin ohjausta tehostaa, pitää kokoojia pystyä analysoimaan prosessivesistä. Työn kirjallisuusosassa on koottu ja vertailtu erilaisia kirjallisuudesta löytyneitä analyysimenetelmiä kokoojakemikaaleille. Kokeellisessaosassa on kehitetty kaksi kapillaarielektroforeesimenetelmää näiden kemikaalien tutkimiseen. Menetelmien toteamisrajat tutkituille kemikaaleille olivat seuraavanlaiset: natrium diiosobutylditiofosfaattille (DTP) 2,7 mg/L puhtaassa vedessä ja 6,7 mg/L prosessivedessä; natrium diisobutyldithiofosfinaatille (DTPI) vastaavasti 4,5 mg/L ja 6,7 mg/L; etyyli ksantaatille 0,025 mg/L ja 0,16 mg/L; ja isobutyyli ksantaatille 0,41 mg/L ja 0,62 mg/L. Näitä menetelmiä voidaan tulevaisuudessa kehittää kokoojien hajoamistuotteiden analysointia varten sekä prosessien on-line mittauksiin.

Lipase and omega-transaminase catalysis in preparation of alcohol and amine enantiomers

Enantiopure intermediates are of high value in drug synthesis. Biocatalysis alone or combined with chemical synthesis provides powerful tools to access enantiopure compounds. In biocatalysis, chemo-, regio- and enantioselectivity of enzymes are combined with their inherent environmentally benign nature. Enzymes can be applied in versatile chemical reactions with non-natural substrates under synthesis conditions. Immobilization of an enzyme is a crucial part of an efficient biocatalytic synthesis method. Successful immobilization enhances the catalytic performance of an enzyme and enables its reuse in successive reactions. This thesis demonstrates the feasibility of biocatalysis in the preparation of enantiopure secondary alcohols and primary amines. Viability and synthetic usability of the studied biocatalytic methods have been addressed throughout this thesis. Candida antarctica lipase B (CAL-B) catalyzed enantioselective O-acylation of racemic secondary alcohols was successfully incorporated with in situ racemization in the dynamic kinetic resolution, affording the (R)-esters in high yields and enantiopurities. Side reactions causing decrease in yield and enantiopurity were suppressed. CAL-B was also utilized in the solvent-free kinetic resolution of racemic primary amines. This method produced the enantiomers as (R)-amides and (S)-amines under ambient conditions. An in-house sol-gel entrapment increased the reusability of CAL-B. Arthrobacter sp. omega-transaminase was entrapped in sol-gel matrices to obtain a reusable catalyst for the preparation enantiopure primary amines in an aqueous medium. The obtained heterogeneous omega-transaminase catalyst enabled the enantiomeric enrichment of the racemic amines to their (S)-enantiomers. The synthetic usability of the sol-gel catalyst was demonstrated in five successive preparative kinetic resolutions.

Litiumin talteenotto väkevistä kloridiliuoksista solvatoivilla uuttoreagensseilla

Tämän kandidaatintyön tarkoituksena oli selvittää voidaanko litiumia erottaa suolaliuoksesta solvatoivien uuttoreagenssien avulla suoraan ilman tavanomaisia monivaiheisia prosesseja. Kirjallisessa osassa esitellään neste-nesteuuton periaatteet ja tarkastellaan litiumin talteenotossa käytettyjä uuttomenetelmiä sekä litiumin merkitystä yhteiskunnallisti. Kokeellisessa osassa tutkittiin litiumin uuttoa litiumtetrakloroferraattina vesiliuoksesta, jonka koostumus oli lähellä Argentiinan Rinconin alueen suolajärvien vettä sisältäen litium-, kalsium-, magnesium-, sekä natriumkloridia. Kokeet suoritettiin erotussuppiloissa huoneenlämmössä käyttäen orgaanisena faasina tributyylifosfaatin (TBP) ja kerosiini, tributyylifosfaatin ja di-isobutyyliketonin sekä tributyylifosfaatin ja metyyli-isobutyyliketonin seoksia. Kullakin orgaanisella faasilla tehtiin kaksi koesarjaa. Ensimmäisessä vaihdettiin liuoksen [Fe3+]/[Li+]-suhdetta orgaanisen faasin TBP-pitoisuuden ollessa vakio. Toisessa muutettiin orgaanisen faasin TBP-pitoisuutta [Fe3+]/[Li+]-suhteen pysyessä vakiona. Litium saatiin talteenotettua hyvin selektiivisesti magnesiumin ja kalsiumin suhteen. Rautakonsentraation lisäyksen huomattiin lisäävän litiumin saantoa, mutta suurilla rautakonsentraatioilla selektiivisyys oli huonompi. Litiumia ei saatu erotettua kovin tehokkaasti, johtuen todennäköisesti suuresta natriumkonsentraatiosta. Suurin osa natriumista tulisi poistaa ennen uuttoa. Jos natriumin saisi poistettua tehokkaasti ennen uuttoa, voisi tutkittu menetelmä olla huomattavasti nopeampi verrattuna perinteiseen monivaiheiseen litiumin talteenottoprosessiin. Menetelmän huonona puolena on kuitenkin sen suuri raudan kulutus

Study of the volatile compounds from plum (Prunus domestica L. cv. Horvin) and estimation of their contribution to the fruit aroma

Simultaneous Distillation-Extraction (SDE) and headspace-solid phase microextraction (HS-SPME) combined with GC-FID and GC-MS were used to analyze volatile compounds from plum (Prunus domestica L. cv. Horvin) and to estimate the most odor-active compounds by application of the Odor Activity Values (OAV). The analyses led to the identification of 148 components, including 58 esters, 23 terpenoids, 14 aldehydes, 11 alcohols, 10 ketones, 9 alkanes, 7 acids, 4 lactones, 3 phenols, and other 9 compounds of different structures. According to the results of SDE-GC-MS, SPME-GC-MS and OAV, ethyl 2-methylbutanoate, hexyl acetate, (E)-2-nonenal, ethyl butanoate, (E)-2-decenal, ethyl hexanoate, nonanal, decanal, (E)-β-ionone, Γ-dodecalactone, (Z)-3-hexenyl acetate, pentyl acetate, linalool, Γ-decalactone, butyl acetate, limonene, propyl acetate, Δ-decalactone, diethyl sulfide, (E)-2-hexenyl acetate, ethyl heptanoate, (Z)-3-hexenol, (Z)-3-hexenyl hexanoate, eugenol, (E)-2-hexenal, ethyl pentanoate, hexyl 2-methylbutanoate, isopentyl hexanoate, 1-hexanol, Γ-nonalactone, myrcene, octyl acetate, phenylacetaldehyde, 1-butanol, isobutyl acetate, (E)-2-heptenal, octadecanal, and nerol are characteristic odor active compounds in fresh plums since they showed concentrations far above their odor thresholds.

Investigations of 2-alkyl-3-methoxypyrazines in three ladybug species and wine /

Investigations of 2-alkyl-3-methoxypyrazines (2-isopropyl-3-methoxypyra2ine, 2- secbutyl-3-methoxypyrazine and 2-isobutyl-3-niethoxypyrazine) in ladybug species {Coleoptera: Coccinellidae) and wine samples have been conducted. Headspace sampling coupled with gas chromatography-mass spectrometry was used to determine amounts of 2-alkyl-3-methoxypyra2ines in the ladybug species. Hippodamia convergens had the highest amount of alkybnethoxypyrazines, followed by Harmoma axyridis and the least in Coccinella septempunctata. Using a solvent extraction method, the precoccinelline alkaloid was found present in Hippodamia convergens and Coccinella septempunctata but not Harmonia axyridis. Steam distillation followed by a soHd phase extraction method as a sample preparation technique, enhanced detection while the isotope dilution method afforded accurate quantitation of the alkyknethoxypyrazines in the wine samples. Both ladybug-tainted and commercial wine samples were found to contain the 2- alkyl-3-methoxypyrazines. Wine samples prepared in 2001 generally contained higher levels than the corresponding 2003 samples. Levels of the 2-alkyl-3-methoxypyrazines found in the commercial wines ranged from a minimum value of 6 ng/L to 260 ±10 ng/L. Analyses revealed that for both ladybug species and wine samples, the 2- isopropyl-3-methoxypyrazine had the highest concentration, followed by 2-isobutyl- 3-methoxypyrazine and the least being the 2-secbutyl-3-methoxypyrazine. Possible contamination of the wine samples by ladybugs is thoroughly discussed. Furthermore, attempts to remove or reduce the levels of the alkylmethoxypyrazines with molecularly imprinted polymers from wine samples are presented in detail.

Reactions of some non-enolisable chloroketones with amide ion and a new synthesis of acridones /|nGuo-shyoung John Chen. -- 260 St. Catharines, Ont. : [s. n.],

This research was directed mainly towards the investigation of the reacti.ons of· substituted chlorobenziophenones under strongly basi,c conditions. The work 'can be divided into two main sections. The Introduction deals mainly with historical studies on aryne chemistry and the Haller-Bauer reaction. Secti.on I i.s concerned with syntheses of 2-benzamido-2'chlorobenzophenone and 2-benzamido~3'-chlorobenzophenone,and with thei,r respective reactions wi.th potassium amide in ammonia. o-Chlorophenylacetic acid was converted to the acid chloride and then by Friedel-Craftsreaction with benzene to w-(o-chlorophenyl)acetophenone. Reaction wi.th phenylhydrazine and Fischer cyclization gave 3- (0chlorophenyl)- 2-phenylindole, which was ozonized to 2-benzamido-2'chlorobenzophenone. The isomeric 3' -chlor,..o ke: tone was similarly synthesised from m-chlorophenylacetic acid. Both the 2'- and 3' -ch.loroketones gave N-benzoylacridone on treatment with potassium amide in ammonia; an aryne mechanism is involved for the 3'-chloroketone but aryne and nucleophilic substitution mechanisms are possible for the 2'-chloroketone. Hydrolysis of the 2'- and 3'-chloroketones gave 2-amino-2'chlorobenzophenone and 2-amino-3'-chlorobenzophenone respectively. A second new acridone synthesis is given in the Appendix involving reactions of these two ketones with potassium t-butoxide in t-butylbenzene. i Section 2 deals with the investigation of the reaction of some tricyclic ch1orobenzophenones with potassium amide in liquid ammonia. These were 1-ch1orof1uorenone; which was pr~pared in several steps from f1uoranthene, and 1- and 2-ch1oroanthraquinones. 1-Ch1orof1uorenone gave 1-aminof1uorenone ; 1-ch1oroanthraquinone gave 1- and 2-aminoanthraquinones; 2-ch1oroanthraquinone was largely recovered from the attempted reaction.