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1

The influence of the chain length and the functional group steric accessibility of thiols on the phase transfer efficiency of gold nanoparticles from water to toluene

Soliwoda K., Tomaszewska E., Tkacz-Szczesna B., Rosowski M., Celichowski G., Grobelny J.

Polish Journal of Chemical Technology

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2014

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Vol. 16, nr 1

86--91

EN

This paper describes the influence of the chain length and the functional group steric accessibility of thiols modifiers on the phase transfer process efficiency of water synthesized gold nanoparticles (AuNPs) to toluene. The following thiols were tested: 1-decanethiol, 1,1-dimethyldecanethiol, 1-dodecanethiol, 1-tetradecanethiol and 1-oktadecanethiol. Nanoparticles (NPs) synthesized in water were precisely characterized before the phase transfer process using Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM). The optical properties of AuNPs before and after the phase transfer were studied by the UV-Vis spectroscopy. Additionally, the particle size and size distribution before and after the phase transfer of nanoparticles were investigated using Dynamic Light Scattering (DLS). It turned out that the modification of NPs surface was not effective in the case of 1,1-dimethyldecanethiol, probably because of the difficult steric accessibility of the thiol functional group to NPs surface. Consequently, the effective phase transfer of AuNPs from water to toluene did not occur. In toluene the most stable were nanoparticles modified with 1-decanethiol, 1-dodecanethiol and 1-tetradecanethiol.

2

Bezpośrednia synteza azydków i tioli organicznych pochodnych glikolu etylenowego w zmodyfikowanej reakcji Appela

Stefaniak M., Jasiński M., Urbaniak K., Romański J., Seliger P., Gutowska N

Chemik

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2014

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Vol. 68, nr 7

592--599

PL

Klasyczną metodę konwersji alkoholi pierwszorzędowych w odpowiednie halogenki alkilowe z użyciem trifenylofosfiny oraz tetrahalogenometanu, tzw. reakcję Appela, zaadoptowano do bezpośredniej syntezy terminalnych tioli i azydków organicznych pochodnych glikolu etylenowego oraz jego siarkowego analogu. W kluczowym etapie opisanej procedury one-pot, otrzymane in situ, w reakcji z N-bromosukcynimidem (NBS), odpowiednie dibromopochodne zostały przekształcone w związki docelowe w reakcji z nukleofilem siarkowym lub azotowym. Wybrane diazydki wykorzystano w syntezie nowych układów makrocyklicznych, które przetestowano pod kątem ich właściwości kompleksotwórczych.

EN

Classical method of conversion of primary alcohols into corresponding alkyl halides by usage of triphenylphosphine and tetrahalogenated methane, so-called Appel reaction, was adopted for the direct synthesis of terminal organic thiols and azides derived from ethylene glycol and its sulfurated analogue. In key step of the presented ‘one-pot’ protocol, corresponding dibromides, generated in situ via reaction with N-bromosuccinimide (NBS), were converted into desired products by treatment with appropriate sulfur or nitrogen nucleophile. A series of diazides and dithiols derived from (poly)ethylene glycols and their sulfur analogues were obtained. Selected diazides were utilized for the construction of novel macrocyclic systems, that were tested incontext of their complexing properties.

3

Wykorzystanie derywatyzacji w analizie próbek biologicznych na zawartość aminotioli techniką wysokosprawnej chromatografii cieczowej z detekcją UV-Vis

Głowacki R.

Wiadomości Chemiczne

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2009

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[Z] 63, 11-12

1049-1071

EN

Thiols are chemically and biochemically very active components of the sulfur cycle of the natural environment. Low molecular-mass thiols, such as homocysteine, cysteine, cysteinylglycine and glutathione are critical cellular components that play numerous roles in metabolism and homeostasis, and are important in a variety of physiological and pathological processes [1, 2]. Plasma thiols are being investigated as potential indicators of health status and disease risk [3.8]. Because of high affinity to oxidation low-molecular-mass thiols exist in biological samples mostly as symmetrical, unsymmetrical and protein-bound disulfides. Thus, determination of total thiol content must comprise disulfide bond disruption step. A reducing agent is necessary both for the reduction of the sulfide bonds and to keep the thiol in a reduced form until start of derivatization. Most of thiols lack the structural properties necessary for the production of signals compatible with common HPLC detectors, such as UV absorbance and fluorescence. Therefore, an analyst must resort to derivatization for signal enhancement and labile sulfhydryl group blocking if fluorescence or UV-Vis detection methods are employed. Ultraviolet detection is less specific and less sensitive than fluorescence one, nevertheless, its sensitivity is sufficient for detection and quantitation of endogenous and exogenous thiols in biological samples in physiological and pathological conditions. Moreover, equipment for HPLC-UV analysis is often a part of an existing, standard instrumentation in hospital laboratories and staff is usually well experienced in its use. All methods, except those based on electrochemical and tandem-mass spectrometry detection, depend on pre- or post-column derivatization of thiols. Useful reagents must form thiol derivatives with sufficient absorption and/or fluorescent yield to measure thiols at trace concentrations. Furthermore, the ideal reagent should show no absorption and should react rapidly and specifically with thiols to form stable products. Numerous reagents are available for the thiol derivatization. A majority of the reagents can be classified by type of the reactive moiety into three categories: activated halogen compounds, disulfides, and compounds possessing maleimide moiety, and are reviewed with some experimental details in excellent works [36.41].

4

Studies on the free-radical addition of thiols to multiacrylate

Jantas R., Draczyński Z.

Polish Journal of Applied Chemistry

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2009

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Vol. 53, nr 1

31-36

EN

Free-radical addition of thiols (l-dodecanthiol, 2-hydroxy-l-ethanethiol) to vinyl groups of a multiacrylate - poly(2-acryIoyloxyethyl methacrylate) were investigated. The addition process was carried out in dioxane with the excess of thiols within the temperature range 60-80°C. Pseudo-first-order rate constants for free-radical addition and the activation energy were determined. The resultant comb-like products were characterized by FTIR, H-NMR, C-NMR and DSC.

5

Spectrophotometric determination of thiols in pure sub stances and pharmaceutical preparation

Skowron M., Ciesielski W.

Chemia Analityczna

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2009

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Vol. 54, No. 4

743-751

EN

A spectrophotometric method for determination of mesna (MA), 6-mercaptopurine (MP), 6-thioguanine (TG), and 6-propyl-2-thiouracil (PTU) has been developed. The method was based on the reaction of thiouracils with N,N-dimethyi-p-phenylenediamine (DMPD) in acidic solution in the presence of the Fe3++ ion, an oxidising agent. Absorbance of the obtained coloured products was measured at the corresponding optimum wavelengths: 490 nm for MA (ε=1.9x103L mol-1 cm-1), 455 nm for MP (ε = 1.9 x 10-1 I, mol-1 cm-1), 460nmforTG(ε=l.6x 103 L mol cm-1), and 465 nm for PTU (s = 2.l x 10-1L mol-1 cm-1). Beer's law was obeyed in the following concentration ranges: 8.2 x 10-2-9.0 x 10-2 g L-1 for MA, 6.0 x 10-1-3.8x 10-1gL--1forMP,4.2x 1Q-M.2 x 10-2 g L-1 for TG and 4.2 x 10--3--3.9 x 10-2 g L-1 for PTU. The method has been applied for determination of thiols in pharmaceuticals.

PL

Opracowano spektrofotometryczną metodę oznaczania mesny (MA). 6-merkaptopu-ryny (MP), 6-tioguaniny (TG) i 6-propylo-2-tiouracylu (PTU). Metoda W7korzystuje reakcję tiouracyli z N,N-dimetylo-p-fenylenodiamią w środowisku kwaśnym, w obecności jonów Fe+2 jako utleniacza. Absorbancję barwnych produktów reakcji mierzono przy długościach fali K = 490 nm dla MA (e = 1.9 x 103L mol cm-1), X = 455 nm dla MP (E = 1.9 x l05 L mol-1 cm-1), K = 460 nm dla TG (e = 1.6 x l0M, mol-1 cm-1) i X. = 475 nm dla PTU (ε= 2. l x l0-1 L mol-1 cnr')- Prawo Beera jest spełnione w zakresie stężeń 8.2 x &epsilon-9.0x 10-1 g L-1dla MA, 6.0 x 10--13.8x 10-1g L-1dla MP, 4.2 x 10MA.2 x 10'-2 g L-2dla TG and 4.2 x 10-1-3.9 x 1010-2 g L-1 dla PTU. Opracowaną metodę wykorzystano do oznaczaniazwiązków w preparatach farmaceutycznych.

6

Oktakarboksyftalocyjaniny jako katalizatory utleniania związków siarki

Nackiewicz J., Suchan A., Wacławek W.

Proceedings of ECOpole

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2007

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Vol. 1, No. 1/2

191--194

PL

Zbadano aktywność katalityczną oktakarboksyftalocyjaniny kobaltu (CoPcOC), żelaza (FePcOC) i miedzi (CuPcOC) w aerobowym utlenianiu 2-tioetanolu, siarczku sodu i L-cystciny. Kompleksy kobaltu i żelaza okazały się efektywnymi katalizatorami homofazowymi tych reakcji. Na ich aktywność katalityczną mają wpływ takie czynniki, jak rodzaj skomplcksowanego metalu, wartość pH, stopień asocjacji w roztworze.

EN

Octacarboxyphthalocyanines (MPcOC) were investigated as potential catalysts in aerobic oxidation of sulfur containing compounds. The investigations of their catalytic activity are interesting both regarding the basic research and owing to their ecological aspects. Water-soluble thiols and sulfides are highly dangerous for natural environment. Their oxidation leads to the markedly less harmful compounds. The catalytic activities of cobalt (CoPcOC), iron (FePcOC) and copper (CuPcOC) octacarboxyphthalocyanines in reaction of aerobic oxidation of 2-thioethanol, natrium sulfide and L-cysteine were examined. The complexes of cobalt and iron are effective homogeneous catalysts in the reactions mentioned above. The following factors have impact on their activity: metal complexed, pH value and degree of association.

7

Oktakarboksyftalocyjaniny jako katalizatory utleniania związków siarki

Nackiewicz J., Suchan A., Wacławek W.

Chemia i Inżynieria Ekologiczna

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2007

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Vol. 14, nr S4

497-503

PL

Zbadano aktywność katalityczną oktakarboksyftalocyjaniny kobaltu (CoPcOC), żelaza (FePcOC) i miedzi (CuPcOC) w aerobowym utlenianiu 2-tioetanolu, siarczku sodu i L-cysteiny. Kompleksy kobaltu i żelaza okazały się efektywnymi katalizatorami homofazowymi tych reakcji. Na aktywność katalityczną wpływ mają takie czynniki, jak rodzaj skompleksowanego metalu, pH, asocjacja ftalocyjanin w roztworze.

EN

In this preliminary paper the octacarboxyphthalocyanines (MPcOC) were investigated as potential catalysts in aerobic oxidation of sulfur containing compounds. The investigations of their catalytic activity are interesting both regarding the basic research and owing to their ecological aspects. Water-soluble thiols and sulfides are highly dangerous for natural environment. Their oxidation leads to the markedly less harmful compounds. The catalytic activities of cobalt (CoPcOC), iron (FePcOC) and copper (CuPcOC) octacarboxyphthalocyanines in reaction of aerobic oxidation of 2-thioethauol, natrium sulfide and L-cysteine were examined. The complexes of cobalt and iron are effective homogeneous catalysts in above-mentioned reactions, especially in alkalized solutions. The following factors have impact on the activity the metal complexed, pH value, association of the phthalocyanines in the solutions investigated.

8

Cobalt, copper and zinc octacarboxyphthalocyanine activity in anaerobic oxidation of -SH group containing compounds

Nackiewicz J., Suchan A., Wacławek W.

Chemia i Inżynieria Ekologiczna

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2007

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Vol. 14, nr 10

1119-1127

EN

The series of electrochemical measurements were carried out to evaluate the catalytic activity of cobalt, copper and zinc octacarboxyphthalocyanine in oxidation of organic compounds having -SH group. 2-thioethanol (TE), L-cysteine and 1,4-dithio-2,3-butanediol (DTT) were investigated as substrates. As counting electrode an ordinary graphite electrode GE was used. The investigations were carried out for solutions in which a potential catalyst was dissolved and for catalyst adsorbed on the surface of GE electrode. Only cobalt octacarboxyphthalocyanine adsorbed on the surface of GE appeared to be good heterogeneous catalyst. All investigated Pcs dissolved in solution did not exhibit catalytic activity.

PL

Wykonano serię pomiarów elektrochemicznych w celu określenia aktywności katalitycznej oktakarboksyftalocyjaniny kobaltu, cynku i miedzi w anaerobowym utlenianiu związków organicznych zawierających grupę-SH. Badano następujące substraty: 2-tioetanol (TE), L-cysteinę i 1,4-ditio-2,3-butanodiol (DTT). Jako elektrodę wskaźnikową stosowano elektrodę grafitową GE. Przeprowadzono badania dla roztworów substratów, w których potencjalny katalizator był rozpuszczony, jak i dla roztworów, w których katalizator był zaadsorbowany na powierzchni elektrody GE. Jedynie oktakarboksyftalocyjanina kobaltu, CoPcOC, zaadsorbowana na powierzchni elektrody grafitowej okazała się dobrym katalizatorem heterogennym. Wszystkie badane ftalocyjaniny rozpuszczone w roztworach nie wykazały aktywności katalitycznej.

9

Oxidizability of cysteine and short cysteine-containing peptides by molecular oxygen

Dorcak V., Mader P., Vesela V., Fedurco M., Sestakova I.

Chemia Analityczna

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2007

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Vol. 52, No. 6

979-988

EN

Rate of oxidation of cysteine. y-glutamylcysteine. cysteinylglycine and reduced glutathione by molecular oxygen has been studied polarographically in alkaline buffers by foliowing the time changes in anodic and cathodic limiting currents of the SH- and SS-groups, respectively. Oxidation of thiols proceeds considerably faster in contact with metallic mercury. Obtained results have been supported by Raman spectroscopy measurements.

PL

Badano polarograficznie szybkość utleniania cysteiny, gamma-glutamylocysteiny. cystci-nogiicyny i zredukowanego glutationu, tlenem cząsteczkowym w roztworach alkalicznych, śledząc zmiany czasu w anodowym i katodowym prądzie granicznym, odpowiednio dla grup SH- i SS-. W obecności metalicznej rtęci utlenianie tioli przebiegało znacznie szybciej. Otrzymane wyniki potwierdzono za pomocą spektroskopii Ramana.

10

Iodometric titration of sulfur compounds in alkaline medium

Ciesielski W., Zakrzewski R.

Chemia Analityczna

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2006

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Vol. 51, No. 5

653-678

EN

The possibilities of application of iodine as a titrant in determination of sulfur compounds have been presented. The influence of the reaction medium, the nature of compounds, and the thiol-thione tautomerism on the reaction sto ich io metry of sulfur compounds with iodine has been discussed. The conditions of volumetric titration with visual and potentio-metric end-point detection and coulometric titration with biamperometric end-point detection have been described. The advantages of the applied analytical techniques in the determination of selected sulfur compounds in fannaceutical preparations have been presented.

PL

Przedstawiono możliwości zastosowania jodu jako titrantu do oznaczania związków siarki. Omówiono wpływ środowiska reakcji, budowy cząsteczki związku oraz tautomerii tiol-tion na stechiometrię reakcji związku siarki z jodem. Opisano warunki zastosowania miareczkowania objętościowego z wizualną i potencjometryczną detekcją punktu końcowego, a także miareczkowania kulometrycznego z biamperometryczną detekcją punktu końcowego. Przedstawiono zalety stosowanych technik analitycznych do oznaczania wybranych związków siarki w preparatach farmaceutycznych.

11

Modyfikacje nienasyconych estrów skrobi aminami i tiolami

Stawski D.

Zeszyty Naukowe. Włókiennictwo / Politechnika Łódzka

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2005

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z. 61

45-56

PL

W pracy zsyntezowano estrowe pochodne skrobi (akrylan i metakrylan) metodą międzyfazowej estryfikacji skrobi odpowiednimi chlorkami kwasowymi. Zbadano nieopisaną dotąd w literaturze nukleofilową addycję amin pierwszo- i drugorządowych oraz tioli do grup winylowych akrylanu i metakrylanu skrobi. Określono wpływ temperatury, rodzaju aminy, stopnia podstawienia i rodzaju rozpuszczalnika na kinetykę addycji do akrylanu skrobi. Porównano odporność termiczną skrobi, jej pochodnej estrowej i aminowej. Wykazano działanie antyelektrostatyczne oraz sorpcyjne trzeciorzędowych i czwartorzędowych pochodnych skrobi.

EN

Ester derivatives of starch, which contain reactive vinyl bonds, such as starch acrylate and methacrylate, were synthesized. The synthesis of these compounds, which had not been sufficiently described as yet, was carried out at a low temperature (about -7°C) by the interfacial esterification of starch with appropriate acid chlorides. Under these conditions no degradation of the polysaccharides chain and no side reactions of vinyl bonds take place. Based on the results of elementary analysis and FTIR, H-NMR and C-NMR spectra, the chemical composition of the esterification products has been confirmed. The second stage of this study was intended for detailed investigation of the so far unreported reactions of nucleophilic addition of primary and secondary amines and dodecanitiole to vinyl groups of starch acrylate and methacrylate under the conditions of pseudo-first order reaction. Based on the obtained results it has been found that the effect of temperature on the reaction rate is consistent with the general assumption of chemical kinetics. The calculated activation energies for the secondary amine addition ranged from 13.2 to 24.2 kJ/mol and those for primary amines from 11.7 to 13.0 kJ/mol. A slight effect of THF and dioxane on the addition kinetics was also observed, while the reaction course was slower in DMSO, which is characterized by a considerably higher dielectric constant. On the other hand, a clear decrease in the constants of pseudo-first order reaction rates was observed in the case of primary and secondary amines with different lengths of aliphatic chain. The presence of amine and thiol groups in the products of addition was confirmed by the methods of FTIR, H-NMR and C-NMR. On the basis of the results of thermogravimetric analysis of starch and products of its modification it has been found that the thermal resistance of starch acrylate is slightly higher than that of initial starch and the degree of substitution with ester groups exerts no significant influence on their thermal stability. The starch derivatives containing tertiary amine groups and anionic groups were successfully used as an antistatic finish for polyester fabrics. The use of N,N-dipropylaminepropionate of starch as a sorbent of copper ions has been also investigated. The results obtained show that the amine derivatives of starch can combine about 1.5 mmole of Cu2+/g sorbent after 10 h.

12

Coulometric titration of thiols with electrogenerated chlorine

Ciesielski W., Skowron M.

Chemia Analityczna

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2004

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Vol. 49, No. 5

619-626

EN

Coulometric titration of thiols with chlorine in solution containing different electrolytes has been performed. Optimum determination conditions have been found. The developed method was applied to the determinaton of mesna (0.25-10 žmol), L-cysteine (0.25-2 žmol), mercaptosuccinic acid (0.5-2.5 žmol), 3-mercaptopropionic acid (0.42-8.3 žmol), cysteamine hydrochloride (0.5-3 žmol), carbimazole (0.25-2 žmol), thiopental (0.1-1 žmol), thioglycolic acid (0.87-10 žmol), D-penicillamine (0.125-5 žmol), L-glutathione (0.5-10 žmol) and mesna in pharmaceutical preparations (Mistabron and Anti-Uron). Determination error was below 1%.

PL

Przeprowadzono miareczkowanie kulometryczne tioli z użyciem chloru jako titranta w środowisku różnych elektrolitów. Opracowano optymalne warunki oznaczenia. Za pomocą opracowanej metody oznaczono mesnę (0.25-10 umol). L-cystcine (0.25-2 umol), kwas merkaptobursztynowy (0.5-2.5 umol), kwas 3-mcrcaptopropłonowy (0.42-8.3 |umol), chlorowodorek cysteaminy (0.5-3 umol), karbimazol (0,25-2 umol), tiopental (0.1-1 p.mol), kwas tioglikolowy (0-87-10 umol), D-penicyloamine. (0.125--5 umol), L-glutation (0.5-10 H-mol) oraz mesnę w preparatach farmaceutycznych Mistabron i Anti-Uron. Opracowana metoda umożliwia oznaczanie tioli z błędem poniżej 1%.

13

Cine-Substitution of Nitro Group in 1-Aryl-2-methyl-4-nitroimidazoles by Thiols; X-ray Diffraction Proof for the Product Structure

Suwiński J., Świerczek K., Wagner P., Kubicki M., Borowiak T.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 5

639-647

EN

1-Aryl-2-methyl-4-nitroimidazoles react with 2-amino- or with 2-hydroxyethanethiols to give products of cine-substitution of the nitro group. 5-(2_-Hydroxyethylthio)-2- methyl-1-phenylimidazole has been isolated as a free base, other products in the form of dipicrates. A structure of 5-(2_-aminoethylthio)-2-methyl-1-phenylimidazole dipicrate was proved by X-ray diffraction.

14

Photopolymerization of dimethacrylates in the presence of 2-mercaptobenzothiazole (MBT) and 2,2'-benzothiazole disulfide (BTDS)

Andrzejewska E., Andrzejewski M., Zych-Tomkowiak D.

Polimery

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2000

|

T. 45, nr 9

639-641

EN

The effect of a heteroaromatic thiol and disulfide, viz. MBT and BTDS, was preliminarily studied in the photopolymerization of tetraethylene and triethylene glycol dimethacrylates (TETGDM, TEGDM), initiated with type I (Irgacure 369) and type II (camphorquinone, CQ) photoinitiators and benzoyl peroxide (BPO) as thermal initiator in air or in Ar. Polymerization was run under 300-400 run or > 400 run irradiation (Hg and halogen lamp, resp.) and its kinetics was followed by isothermal DSC [9] (Figs. 1-3). In Ar, the additives had no influence on the Irgacure 369-initiated polymerization of TETGDM; in air, each additive retarded the polymerization and decreased the conversion of double bonds. Retardation of polymerization by additives was also observed, both in air and in Ar, in the process initiated by BPO. In the CQ-initiated polymerization of TEGDM the additives accelerated the polymerization. In air, BTDS raised the maximum polymerization rate to a value somewhat lower man did MBT, and did not reduce the induction period. In Ar, BTDS accelerated the polymerization considerably, much more then did MBT. Results are discussed in terms of the hydrogen abstraction and chain transfer reactions and also photochemical reactions of the additives.

PL

Zbadano wstępnie wpływ dodatku heteroaromatycznych tioli i disulfidów (MTB i BTDS) na przebieg fotopolimeryzacji dimetakrylanów glikoli tetraetylenowego i trietylenowego (odpowiednio TETGDM i TEGDM), inicjowanych "Irgacure 369" (inicjator fotofragmentujący) lub kamforochinonem (inicjator odrywający atom wodoru), w warunkach napromieniowania w zakresie 300-400 nm lub >400 run. Zastosowano również inicjator termiczny (nadtlenek benzoilu). Kinetykę polimeryzacji śledzono metodą izotermicznej DSC [9] (rys. l-3). W atmosferze argonu dodatki nie wpływały na polimeryzację TETGDM (temp. 40°C) inicjowaną "Irgacure 369"; w atmosferze powietrza oba dodatki opóźniały polimeryzację i zmniejszały konwersję wiązań podwójnych. Spowolnienie polimeryzacji przez dodatki obserwowano również przy inicjowaniu nadtlenkiem benzoilu (80°C, powietrze i argon). W polimeryzacji inicjowanej kamforochinonem (40°C), zarówno MBT jak i BTDS przyspieszały polimeryzację. W powietrzu BTDS zwiększył maksymalną szybkość polimeryzacji do wartości nieco mniejszej niż w przypadku MBT i nie skrócił czasu indukcji. W argonie uzyskano znaczne przyspieszenie polimeryzacji, szczególnie duże w obecności BTDS. Wyniki przedyskutowano w świetle mechanizmu reakcji odszczepiania wodoru i przenoszenia łańcucha, a także fotochemicznych reakcji, jakim ulegają badane dodatki zawierające siarkę.

15

Intramolecular transformation of thiyl radicals to a-aminoalkyl radicals: ab initio calculations on homocystein

Chhun S., Berges J., Bleton V., Abedinzadeh Z.

Nukleonika

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2000

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Vol. 45, nr 1

19-22

EN

One-electron oxidation of thiols by oxidizing radicals leads to the formation of thiyl and carbon-centered radicals. It has been shown experimentally that in the absence of oxygen, the thiyl radicals derived from certain thiols of biological interest such a glutathione, cysteine and homocysteine decay rapidly by intramolecular rearrangement reactions into the carbon-centered radical. In the present work we have investigated theoretically the structure and the stability of thiyl and carbon-centred radicals of homocystein in order to check the possibility of this rearrangement.