Search

Проведено реакції нуклеофільного заміщення між 5-R-2,3-дихлоро-1,4-нафтохінонами і 4-аміно-5-гетерил- 4H-1,2,4-триазол-3-тіолами. Показано, що взаємодія може відбуватися за двома альтернативними напрямами, які регулюються за допомогою умов реакції. Проведено пошук відмінностей в реагуючих атомах досліджуваних молекул внаслідок порівняння розрахованих індексів Фукуї. Експери- ментально показано вплив електронодонорних та електроноакцепторних замісників у 5 положенні 2,3-дихлор- 1,4-нафтохінону на регіоселективність перебігу реакції нуклеофільного заміщення. Порівняння отриманих спектрів 1H ЯМР з DFT розрахованими для обох можливих форм одержуваних продуктів дає можливість однозначно віднести синтезовані сполуки відповідним структурам. Синтезовані сполуки охарактеризовані за допомогою ІЧ, 1H ЯМР, 13C ЯМР спектроскопії та елементного аналізу. Reactions of nucleophilic substitution between 5-R-2,3-dichloro-1,4-naphthoquinones and 4-amino-5- heteryl-4H-1,2,4-triazoles-3-thiols were carried out. It is shown that the interaction can take place in two alternative ways and the reaction direction is controlled by reaction conditions. Search of differences in atoms reactivity in investigated molecules by comparing the calculated Fukui atonic indices was conducted. The influence of electron donor and electron acceptor substituent in 2,3-dichloro- 1,4-naphthoquinone 5th position on the nucleophilic substitution reaction regioselectivity was shown experimentally. Comparison of obtained 1H NMR spectra with DFT calculated for both possible isomers of obtained products allowed to uniquely attribute synthesized compounds to relevant structures. The synthesized compounds were characterized by IR, 1H NMR, 13C NMR spectroscopy and elemental analysis.

Була проведена та досліджена на B3LYP/6-31G(d,p) рівні реакція Дільса-Альдера азо-біс- ціанурхлориду як електрофільного дієнофілу з рядом дієнів з різною нуклеофільністю, а саме 2,3-диметилбутадієну, 2-ме- тилбутадієну і 1-ацетоксибутадієну. Визначено, що реакція проходить за м’яких умов та з високими виходами. Обчислені глобальні та локальні індекси реакційності, а також геометрії перехідних станів та енергії активації. Вивчені напрямки подальшої модифікації одержаних продуктів заміщенням атомів хлору. Встановлено, що сполуки є стійкими в лужних умовах, але швидко руйнуються у присутності кислот. The reaction of azo-bis-cyanuric chloride as strong electrophilic aza-dienophile in Diels-Alder cycloaddition with a number of dienes of different nucleophilicity, namely 2,3-dimethylbutadiene, 2-methylbutadiene and 1-acethoxybutadiene, was carried out and computationally analyzed on B3LYP/6-31G(d,p) level. Local and global reactivity indices, based on FMO theory, as well as TS geometries and activation energies were calculated. Reaction proceeds rapidly with high yields and in mild conditions. Ways of products further modification by chlorine atoms substitution were also studied. Compounds were found to be stable in alkaline conditions but rapidly decompose in the presence of acids.

Novel thiopyrano[2,3-d]thiazole derivatives were synthesized from 5-arylidene-4-thioxo-2-thiazolidinones and 2(5H)furanone in 62–79% yields via hetero-Diels–Alder reactions and related acylation-based tandem processes. The reaction of 5-(4-fluorophenyl)-4-thioxo-2-thiazolidinone with 2(5H)furanone was studied by DFT at the M06-2X/6-31+G(d,p) level. The stereo- and regioselectivities of cycloaddition were confirmed by NMR spectra and single-crystal X-ray diffraction analyses.

The aim of the work was the synthesis of new S-, N-containing heterocyclic naphthoquinone derivatives and evaluation of antimicrobial activity, which is important in terms of finding new drugs. The implementation of this approach can be made by nucleophilic substitution between N, S-bifunctional heterylaminothiotriazoles 2,3 and 2,3-dichloro-1,4-naphthoquinone 1. So the reaction between 2,3-dichloro-1,4-naphthoquinones and 4-amino-5-(2-methyl-furan-3-yl)-2,4-dihydro-[1,2,4]triazole-3-thione was investigated. It was established that the use of dimethylformamide as the reaction medium leads to the formation of two products with dominating yield of S-substitution products. Investigation of antimicrobial activity of the synthesized compounds showed that cultures of Escherichia coli, Aspergillus niger and Candida tenuis are not sensitive to 1,4-naphthoquinone heterocyclic derivatives 4, 5 ,6, 7. But compounds 5, 7 showed antibacterial activity with respect to Staphylococcus aureus and Mycobacterium luteum.

New aromatic aldimines, isatine substituted ketimines based on (4,6-dichloro-1,3,5-triazin-2-yl)-hydrazine scaffold and polycyclic fused thiopyranothiazoles formed using hetero-Diels-Alder reactions starting from 4-thioxo-2-thiazolidinones and 5-norbornene-2,3-dicarboxylic acid triazino-derivatives synthetic approach is described. The application of condensation and cyclocondensation reactions of N-nucleophiles and carbonyl agents for synthesis a number of biologically active triazine derivatives is reported. Screening of anticancer activity in vitro yielded the most active compounds 3a, 8b, and 8f for different cell lines.

Novel thiopyrano[2,3-d]thiazole derivatives were synthesized from 5-arylidene-4-thioxo-2-thiazolidinones and 2(5H)furanone in 62–79% yields via hetero-Diels–Alder reactions and related acylation-based tandem processes. The reaction of 5-(4-fluorophenyl)-4-thioxo-2-thiazolidinone with 2(5H)furanone was studied by DFT at the M06-2X/6-31+G(d,p) level. The stereo- and regioselectivities of cycloaddition were confirmed by NMR spectra and single-crystal X-ray diffraction analyses.

International audience; 2-Bromo-3-(2-bromophenyl)naphthalene-1,4-dione was synthesized as a key precursor to obtain a number of functionalized benzo[b]carbazole-6,11-diones by double Buchwald-Hartwig coupling reaction.

International audience; Thiosulfonate derivatives based on quinones were synthesized for studying "structure-activity relationship" compounds with an acylated and a free amino-group. Anti-platelet activity of the synthesized compounds was determined and the influence of substituents on the activity of the derivatives was assessed.

International audience; [3-(6-Chloropyridazin-3-yl)-3,4-dihydropyridazino[4,5-b]quinoxalin-2(1H) -yl](phenyl)methanone has been synthesized and its two stable forms were isolated. For the establishment of their structures, B3LYP geometry and energy and GIAO/B3LYP NMR calculations of possible conformers using the polarizable continuum model were performed. The differences in calculated spectra allow attributing calculated structures and obtained substances by their H-1 and C-13 NMR. The conformer ratio correlates with their calculated Gibbs energies.

The screening of the in vitro anticancer activity of the synthesized compounds shows that compounds (IVa), (VIIIb), (VIIId) are the most active compounds against different cell lines.

The optimisation of reaction conditions for obtaining thiosulfonate derivatives was performed. S,N-binucleophiles (sodium salts of 4-amino- and 4-acetylaminobenzenethiosulfonic acids) were used. The parameters of the reaction for the synthesis of derivatives by a thiosulfonate fragment were determined. Thiosulfonate derivatives based on a number of quinones and quinoxalines were synthesized. DOI: http://dx.doi.org/10.5755/j01.ct.64.2.6019

Poly( N -methacryloyl- l -leucine) (PNML) coatings were successfully fabricated via polymerization from peroxide initiator grafted to premodified glass substrate. Chemical composition and thickness of PNML coatings were determined using time of flight-secondary ion mass spectrometry (TOF- SIMS) and ellipsometry, respectively. PNML coatings exhibit thermal response of the wettability, between 4 and 28 °C, which indicates a transition between hydrated loose coils and hydrophobic collapsed chains. Morphology of the PNML coating was observed with the AFM, transforming with increasing temperature from initially relatively smooth surface to rough and more structured surface. Protein adsorption observed by fluorescence microscopy for model proteins (bovine serum albumin and lentil lectin labeled with fluorescein isothiocyanate) at transition from 5 to 25 °C, showed high affinity of PNML coating to proteins at all investigated temperatures and pH. Thus, PNML coating have significant potential for medical and biotechnological applications as protein capture agents or functional replacements of antibodies (“plastic antibodies”). The high proliferation growth of the human embryonic kidney cell (HEK 293) onto PNML coating was demonstrated, indicating its excellent cytocompatibility.

A new approach to the synthesis of new heterocyclic compounds with triazine and 4-thiazolidone fragments in one molecule is developed. The synthesis methods comprise [2+3]-cyclocondensation reactions essential in the preparative synthesis of 4-thiazolidone derivatives. The reactions of S,N-nucleophiles with C2-cyclization agents for the synthesis of a number of biologically active 2-triazin-4-thiazolidones were investigated. The interaction of thiosemicarbazone of sym-triazine with derivatives of α-halogencarboxylic acids and maleic anhydride resulted in correspondent (2-[2-(4,6-dichloro-1,3,5-triazin-2-yl)hydrazino]-5-(3,4,5- R-p-phenyl-methyliden)-1,3-thiazol-4-ones obtained in the one-step synthesis. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:392–396, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20631