56 research outputs found
4-oxothiazolidine-2-alkylidene vinyl bromides and a,a-dibromo-2-methoxyacetophenone: precursors in synthetically useful transformations initiated by the rare halophilic attack of nucleophiles
Halofilne reakcije predstavljaju vrstu nukleofilnih supstitucionih reakcija do
kojih dolazi kada nukleofil reaguje sa atomom halogena, nakon ega se oslobaa
karbanjon kao odlazea grupa. To su relativno rijetke reakcije koje se dešavaju ukoliko
je klasina nukleofilna supstitucija (karbofilna reakcija) iz nekog razloga otežana i/ili
kada je karbanjon stabilizovan prisustvom elektron-privlanih supstituenata.
Cilj ovog rada je bio da se ispitaju halofilne reakcije i njihova sintetika
primena na dva sistema: 2-alkiliden-4-oksotiazolidin vinil-bromidima i ,-dibrom-2-
metoksiacetofenonu. Znaaj ovih reakcija u sluaju ispitivanih N-nesupstituisanih
tiazolidinskih jedinjenja je u dobijanju novih, potencijalno biološki aktivnih C-5
funkcionalizovanih derivata. Ovakvi derivati se ne mogu dobiti direktno reakcionom
sekvencom C-5 bromovanje/nukleofilna supstitucija, jer je bromovanje Nnesupstituisanih
2-alkiliden-4-oksotiazolidina visoko regioselektivno i kao proizvodi se
dobijaju iskljuivo vinil-bromidi. Znaaj prouavanja ovakvih reakcija u sluaju a,a-
dibrom-2-metoksiacetofenona proistie iz injenice da se selektivno a-
monobromovanje metil-ketona esto teško postiže, a praeno je stvaranjem a,a-dibromderivata
kao sporednih, a ponekad i kao glavnih proizvoda. Mogua kaskadna
halofilna/karbofilna reakcija bi omoguila korišenje dibrom-derivata kao sintetikih
ekvivalenta monobromida, ime bi se izbegla dodatna faza selektivnog debromovanja
radi dobijanja monobrom-derivata, kao znaajnih sintetikih intermedijera. Razliiti
neutralni i anjonski nukleofili su uestvovali u halofilnoj reakciji sa tiazolidinskim vinilbromidima
dajui tri vrste proizvoda: i) proizvod reduktivnog debromovanja, ii)
proizvod supstitucije broma i iii) C-5 funkcionalizovan proizvod. Takoe je pokazano
da se ,-dibrom-2-metoksiacetofenon može upotrebiti kao sintetiki ekvivalent a-
monobromacetofenona.
Pored navedenih halofilnih reakcija, u ovom radu ispitivana je i mogunost
izvoenja Suzuki-Miyaura reakcije na vinil-bromidima, kao i mogua regioselektivnost
ove reakcije na N-supstituisanom tribrompirazolu, a u cilju dobijanja novih,
potencijalno biološki aktivnih jedinjenja. Suzuki-Miyaura reakcija sa derivatima
arilbornih kiselina izvedena na vinil-bromidima nije dala oekivani rezultat, ali je
uspešno izvedena sa N-supstituisanim tribrompirazolima uz visoku regioselektivnost,
pri emu su sintetisani 5-supstituisani 3,4-dibrompirazoli sa 1,1 ekvivalentom arilbornih
kiselina, 3,5-disupstituisani 4-brompirazoli sa 2,2 ekvivalenta arilbornih kiselina i 3,4,5-
trisupstituisani derivati sa 3,5 ekvivalenata arilbornih kiselina.
S obzirom da ispitivani tiazolidini spadaju u grupu push-pull alkena, kod kojih
elektronska delokalizacija izmeu donorskih i akceptorskih grupa na dvostrukoj vezi
ima znaajan uticaj na njihove osobine i hemijsku reaktivnost, uraena je i
kvantifikacija push-pull efekta dvostruke veze.Halophilic reactions are nucleophilic substitution reactions in which
nucleophile attacks halogen atom with the carbanion acting as a leaving group. They are
relatively rare and usually take place if the classic nucleophilic substitution (carbophilic
reaction) is made difficult, and/or if the resulting carbanion is stabilized by electronwithdrawing
substituents.
The aim of the present work was to study halophilic reactions and their
synthetic application on two systems: 2-alkylidene-4-oxothiazolidines vinyl bromides
and ,-dibromo-2-methoxyacetophenone. The significance of the studied reactions in
the case of N-unsubstituited thiazolidine compounds would be the synthesis of novel,
potentially biologically active C-5 substituted derivatives. These derivatives are
impossible to obtain directly by the C-5 bromination/SNC substitution reaction
sequence, since bromination of N-unsubstituited 2-alkylidene-4-oxothiazolidines is
highly regioselective, resulting in the formation of vinyl bromides as sole products.
Significance of the studied reactions in the case of ,-dibromo-2-
methoxyacetophenone arises from the fact that selective a-monobromination of methyl
ketones of often difficult to achieve. ,-Dibromo derivatives can be formed as side
products, or even as major ones. A possible cascade halophilic/carbophilic reaction
would allow the use of dibromo derivatives as synthetic equivalents of monobromo
compounds, thus avoiding the additional step, selective debromination, necessary to
obtain synthetically useful monobromo derivatives. Various neutral and anionic
nucleophiles underwent a halophilic reaction with thiazolidine vinyl bromides yielding
three types of products: i) products of reductive debromination, ii) bromine susbtitution
products and iii) C-5 functionalized products. It has also been shown that ,-dibromo-
2-methoxyacetophenone can be used as synthetic equivalent of a-monobromo
acetophenone.
Apart from the mentioned halophilic reactions, a possibility of Suzuki-Miyaura
reaction to take place with the vinyl bromides was investigated, along with the possible
regioselectivity of the same reaction applied to N-substituted tribromopyrazoles, all with
the aim to obtaine new, potentially biologically active compounds. Suzuki-Miyaura
reaction of vinyl bromides with aryl boronic acid did not give the expected
tetrasubstituted alkenes. On the contrary, Suzuki-Miyaura reaction performed with the
N-substituted tribromopyrazoles showed high regioselectivity yielding 5-substituted
3,4-dibromopyrazoles with 1.1 equivalent of aryl boronic acids, 3,5-disubstituted 4-
bromo derivatives with 2.2 equivalents of aryl boronic acids and 3,4,5-trisubstituted
derivatives with 3.5 equivalents of aryl boronic acids.
Studied thiazolidine derivatives belong to the class of the so-called push-pull
alkenes in which electronic delocalization beween donor and acceptor groups attached
at the C=C double bond highly influences their properties and chemical reactivity. For
this reason, one aim of the present work was also to quantify this push-pull effect of the
studied compounds
Testamentary capacityand disinheritance
Pořizovací způsobilost a vydědění Abstrakt Vydědění je institutem dědického práva, který dává možnost zůstaviteli, aby nepominutelnému dědici nezanechal povinný díl, na který má ze zákona nárok, popřípadě jej v tomto povinném díle zkrátil. Takto může zůstavitel jednat pouze za předpokladu, že jsou naplněny zákonem stanovené podmínky vydědění. Zákonodárce ovšem explicitně neuvádí, kdo je k tomuto jednostrannému právnímu jednání způsobilý. Tuto skutečnost dovozujeme logicky. Cílem této diplomové práce je zhodnotit a uceleně vyložit institut vydědění a dát jej do souvislosti s pořizovací způsobilostí. Zároveň poukázat na problematiku zákonného vymezení institutu pořizovací nezpůsobilosti a zhodnotit, zda mohla být pořizovací způsobilost k vydědění v zákoně vymezena jiným způsobem. Stěžejní problematikou práce je institut vydědění, jeho celkový rozbor a demonstrace na příkladech z judikatury. Diplomová práce je systematicky rozdělena do čtyř kapitol, které jsou následně dále členěny do podkapitol. První kapitola stručně a věcně vysvětluje základní pojmy dědického práva, které jsou v souvislosti s vyděděním používány. Dále demonstruje nejdůležitější z právních zásad, které se této problematiky týkají. Druhá z kapitol pojednává o institutu pořizovací nezpůsobilosti. Je zde poukázáno na to, že může být...Testamentary capacity and disinheritance Abstract Disinheritance is an institute of law, which gives the testator opportunity to shorten, or not to leave the forced share to the forced heir for which he is entitled by law. The testator can act in this way only if grounds for disinheritance are met. Grounds for disinheritance are defined by law. However, the legislator does not explicitly state who has this legal capacity. We infer this fact logically. The purpose of diploma thesis is the institute of disinheritance, its overall analysis and demonstration on examples from case law. Also, to evaluate the institute of testamentary incapacity, or the incapacity to make disposition of property upon death, and the institute of disinheritance and put them into context. At the same time, to point out whether legal definition of the testamentary incapacity could have been defined in a different way in the law. The diploma thesis is systematically divided into four chapters, which are then divided into subchapters. The first chapter explains the basic terms which are used in connection with institute of disinheritance. It also demonstrates the most important of the legal principles related to it. The second chapter deals with incapacity to make disposition of property upon death. It is pointed out here that the...Department of Civil LawKatedra občanského právaPrávnická fakultaFaculty of La
Supplementary material for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Theoretical Study of Azido: Gauche Effect and Its Origin. New Journal of Chemistry 2017, 41 (11), 4644–4661. https://doi.org/10.1039/c7nj00369b
Supplementary material for: [https://doi.org/10.1039/c7nj00369b]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2464
Supplementary data for article: Aleksić, J.; Stojanović, M.; Baranac-Stojanović, M. Origin of Fluorine/Sulfur Gauche Effect of β-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion. Journal of Organic Chemistry 2015, 80 (20), 10197–10207. https://doi.org/10.1021/acs.joc.5b01779
Supporting information for: [https://doi.org/10.1021/acs.joc.5b01779]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1981
Supplementary data for article: Aleksić, J.; Stojanović, M.; Baranac-Stojanović, M. Origin of Fluorine/Sulfur Gauche Effect of β-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion. Journal of Organic Chemistry 2015, 80 (20), 10197–10207. https://doi.org/10.1021/acs.joc.5b01779
Supporting information for: [https://doi.org/10.1021/acs.joc.5b01779]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1981
Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Triplet State (Anti)Aromaticity of Some Monoheterocyclic Analogues of Benzene, Naphthalene and Anthracene. New J. Chem. 2021, 45 (11), 5060–5074. https://doi.org/10.1039/D1NJ00207D.
Supplementary material for: [https://doi.org/10.1039/D1NJ00207D]Related to published version: [https://cherry.chem.bg.ac.rs/handle/123456789/4355
ザイトクカイ ノ ロンリ 24 : ロウソ センジュウ カラ ミギ センカイ シタ Xシ ノ バアイ
Supplementary material for: [https://doi.org/10.1016/j.tet.2015.06.002]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1734
Supplementary material for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Theoretical Study of Azido: Gauche Effect and Its Origin. New Journal of Chemistry 2017, 41 (11), 4644–4661. https://doi.org/10.1039/c7nj00369b
Supplementary material for: [https://doi.org/10.1039/c7nj00369b]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2464
Antivirus and antibacterial filters for face masks based on silver quantum dots
Available face masks, used to protect the respiratory system from various types of pathogens, show unsatisfactory efficiency because the size of viruses like severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is much smaller than the void spaces in these masks. Difficult breathing through some masks quickly tires out, which makes ordinary people avoid wearing them. These facts suggest that a new strategy is desirable for designing protective face masks. The aim of the study was to present new filters for face masks to protect people exposed to high concentrations of bacteria and viruses, particularly SARS-CoV-2. Methods. Filters for these masks were manufactured of dense cotton fabric impregnated with silver quantum dots. The filters were characterized by scanning electron microscopy and ion-coupled plasma mass spectrometry. Wettability properties were determined by measuring contact angles with water, and a color fastness test was performed. Antibacterial assay was performed using Staphylococcus (S.) aureus. Viability quantitative polymerase chain reaction (qPCR) for virus integrity assay and reverse transcription qPCR (RT-qPCR) assay were used for antiviral activity assessment. Results. In vitro assays showed extremely high efficiency of these filters in destroying S. aureus and SARS-CoV-2 virus. The filters also showed high safety and easy breathing possibilities. Conclusion. The high efficiency of these masks against SARS-CoV-2 has been demonstrated through numerous tests, and they have been approved as anti-SARS-CoV-2 masks for the first time in the world. In the meantime, this solution has been applied in practice, and the data obtained about that are very encouraging
Stanje zdravstvenog sistema Republike Srbije u periodu 2004-2012. godine
Introduction The backbone of Serbian health system forms the public healthcare provider network with 355 institutions and around 112,000 employees, owned and controlled by the Ministry of Health and financed mainly by the Republican Health Insurance Fund. The law recognizes private practice that was not included, till recently, in the public funding scheme. New Health Insurance Law (2005) decreased the number of entitlements in the basic health service package. It abolished the right to dental health care for adults (exceptions are: children, older than 65, pregnant women and emergency cases) as well as the right to compensate travel expenses. The aim of this study was to evaluate the effects of health care system of the Republic of Serbia and indicate parameters that determine the state of health of the population, on the ground of data obtained by the Institute of Public Health of Serbia. Results In the period 2004-2012, cardiovascular diseases represented the main cause of illness in Serbia (50%). In 2012 digestive system diseases were on the second place. Neoplasm and nervous system diseases were on the third place. From 2007 to 2012 there was slight decline in the birth rate and number of deaths, but the death rate increased from 13.9 to 14.2. Health care system in Serbia is funded through the combination of public finances and private contributions. Primary care is provided in 158 health care centres and health care stations, secondary and tertiary care services are offered in general hospitals, specialized hospitals, clinics, clinico-hospital centers and clinical centres. Conclusion A significant but not satisfactory progress has been achieved in the field of health status indicators as the most important outcome of the final performance of the health system. The transition of public health care system in Serbia since the communist period to present and slow integration with European Union is unfinished process.Uvod Osnovicu zdravstvenog sistema Republike Srbije čini zdravstvena mreža od 355 državnih zdravstvenih ustanova i oko 112.000 zaposlenih koji su pod kontrolom Ministarstva zdravlja, a finansiraju se preko Republičkog fonda zdravstvenog osiguranja. Zakon poznaje i privatni sektor, koji doskora nije bio uključen u shemu javnog finansiranja. Zakon o zdravstvenom osiguranju iz 2005. godine smanjio je prava u osnovnom zakonu zdravstvenih usluga i ukinuo pravo na stomatološku zdravstvenu zaštitu (s izuzetkom dece, osoba starijih od 65 godina, trudnica i hitnih slučajeva), odnosno pravo na naknadu putnih troškova u vezi s ostvarivanjem prava na zdravstvenu zaštitu. Cilj ovog rada je bio da se na osnovu podataka Instituta za javno zdravlje Srbije 'Dr Milan Jovanović Batut' procene efekti zdravstvenog sistema Republike Srbije i ukaže na parametre ovoga sistema koji određuju stanje zdravlja stanovništva. Rezultati Od 2004. do 2012. godine kardiovaskularne bolesti su bila najčešća oboljenja u Srbiji (50%). U 2012. godini bolesti digestivnog sistema bile su na drugom mestu. Na trećem mestu su maligne i bolesti nervnog sistema. U periodu 2007-2012. zabeležen je i blag pad nataliteta, smanjio se i broj smrtnih slučajeva, ali je stopa mortaliteta porasla sa 13,9 na 14,2. Sistem zdravstvene zaštite u Srbiji se finansira kroz kombinaciju državnih finansija i privatnih doprinosa. Primarna zdravstvena zaštita se odvija u 158 domova zdravlja, zdravstvenih stanica i ambulanti, a sekundarne i tercijarne službe rade u opštim i specijalnim bolnicama, institucijama, klinikama i kliničko- bolničkim centrima. Zaključak Značajan, ali nedovoljan, napredak postignut je u oblasti pokazatelja zdravstvenog stanja, kao najvažnijeg konačnog ishoda učinka zdravstvenog sistema. Tranzicija državnog sistema zdravstvene zaštite u Srbiji od komunističkog perioda do danas i usporeno integrisanje s Evropskom Unijom je nedovršen proces
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