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Linear diepoxide-terminated poly(ethylene glycol) (PEG) of molar mass 600, 1000 and 2000 g mol−1 was end-linked with dendrimer-star polymer (PAMAM) of generations 1.0 in water to prepare architecturally well-defined copolymer hydrogels. The structures and properties of the products were characterized using infrared, 1H NMR, DSC measurements, scanning electron microscopy (SEM) and swelling behavior tests. The swelling behavior of these hydrogels was tested in distilled water at constant temperature and the equilibrium swelling ratio (ESR) was determined for structurally different hydrogels and various environmental conditions, which showed that ESR was influenced by the molecular weight of PEG, the molar ratio of H amine groups/epoxy groups, temperature and pH. Higher ESR was obtained for either longer-chain PEG, non-stoichiometric H amine/epoxy groups ratio, acidic pH or lower temperatures. When the hydrogel was switched from 10 °C to 65 °C and pH 3.5 to 11.5, the swelling behavior of the hydrogels showed good reversibility for swelling–deswelling. When the molecular weight of PEG was changed in the range of 600–2000, the lower critical solution temperature (LCST) of hydrogel increased from 30 to 40 °C. When the molar ratio of H amine/epoxy groups was changed, the LCST was not significantly changed. [ABSTRACT FROM AUTHOR]

The reactions of [1,3]thiazolo[3,2-b][1,2,4]triazol- 7-ium salts with nucleophiles were investigated. Theoretical investigation of reactivity descriptors and structural parameters of [1,3]thiazolo[3,2-b][1,2,4]triazol-7-ium cation was carried out, and the reactivity centers of the model salts were located. An efficient general method for the synthesis of novel poly-functional derivatives of symmetric triazoles from [1,3]thiazolo[3,2-b][1,2,4]triazol-7-ium halides was developed. The structures of the synthesized compounds were confirmed using proton nuclear magnetic resonance (1H NMR), carbon-13 nuclear magnetic resonance (13C NMR), Fourier-transform infrared spectroscopy (FTIR) and single-crystal X-ray analysis. [ABSTRACT FROM AUTHOR]

The hydrazide 5, that was obtained from 1-(4-fluorophenyl)piperazine ( 1), was converted to the corresponding carbothioamides 6a-c by the reaction with alkyl(aryl) isothiocyanates. The synthesis of conazole analogs 10a-f was performed via the intermediary of triazoles 7a-c. The condensation of triazoles 7a-c with several heterocyclic amines in the presence of formaldehyde afforded the corresponding N-aminoalkylated triazoles 11-14. The effect of different catalysts and solvents on conventional and microwave (MW)-prompted reactions was examined. The synthesized compounds were screened for their antimicrobial activities. [ABSTRACT FROM AUTHOR]

Carbothioamides 4a, b, obtained from nalidixic acid, were converted to the corresponding 1,3-thiazolidine derivatives 5a,b by cyclocondensation with 2-bromo-1-(4-chlorophenyl)ethanone. Treatment of 4a,b with base afforded 1,2,4-triazoles 6a,b. The synthesis of 1,3-oxazolidine 7 was performed by the reaction of compound 4a with ethyl bromoacetate. Treatment of 4a with acid produced 1,3,4-thiadiazole 8. The reaction of compounds 6a and 6b with several heterocyclic amines in the presence of formaldehyde gave the corresponding Mannich bases 9-15 containing various pharmacophore groups. Conventional and microwave-assisted methods were used for the synthesis. The effect of an acid catalyst on Mannich reactions was investigated. The structures of the newly synthesized compounds were elucidated on the basis of 1H NMR, 13C NMR, FTIR, EIMS techniques, and elemental analysis. All compounds were screened for their antimicrobial activity. [ABSTRACT FROM AUTHOR]

New pyrazoles have been synthesized and evaluated as breast cancer cell growth inhibitors. Condensation of the substituted pyrazole-4-carbaldehyde 1 with acetophenone and chloroacetophenone afforded α, β-unsaturated ketones 2 and 3, respectively. Compounds 2 and 3 were subjected to different reactions using hydrazine hydrate, substituted hydrazine hydrate, hydroxylamine, o-phenylenediamine, malononitrile under different conditions affording 4-substituted pyrazole derivatives 4-28. Structure elucidation of these compounds was conducted using IR, ¹H NMR, 13C NMR, mass spectral data and elemental analysis. Antitumor activity of target compounds was tested against MCF-7 cell line (human breast cancer). Compounds 4, 10 and 20 show significant antitumor activity against breast cancer. Docking was performed with protein 1UYK to study the binding mode of the designed compounds. [ABSTRACT FROM AUTHOR]

C28H20Cl2F2N8O8, triclinic, P¯1 (no. 2), a=9.045(3) Å, b=10.907(4) Å, c=15.351(5) Å, α=93.416(7)°, β=95.771(7)°, γ=95.915(6)°, V =1495.0(9) Å3, Z =4, Rgt(F)=0.0655, wRref(F2)=0.1940, T=293 K. [ABSTRACT FROM AUTHOR]

C18H20FN3S, triclinic, P..., a=7.3884(4) Å, b=10.0741(6) Å, c=12.6533(8) Å, α=69.209(2)°, β=73.778(2)°, γ=72.638(2)°, V=824.33(8) ų, Z=2, Rgt(F)=0.0480, wRref(F²)=0.1351, T=296(2) K. [ABSTRACT FROM AUTHOR]

C13H14N2O3S, monoclinic, C2/ c (no. 15), a = 27.9910(12) Å, b = 6.5721(3) Å, c = 14.2821(7) Å, β = 92.600(3)°, V = 2624.6(2) Å3, Z = 8, Rgt( F) = 0.042, wRref( F2) = 0.105, T = 100 K. [ABSTRACT FROM AUTHOR]

2-Amino-5-mercapto-1,3,4-thiadiazole (AMT) was used to synthesize 24 new compounds. The structures were confirmed by 1H NMR and 13C NMR. [ABSTRACT FROM AUTHOR]

New N, N-disubstituted 7,7-dimethyl-7,8-dihydro-6 H-benzotetrazolothiadiazine-9-amines were synthesized from sodium 1-amino-1 H-tetrazole-5-thiolate and 2-bromo-5,5-dimethylcyclohexane-1,3-dione in multiple steps. The compounds were characterized by 13C NMR, 1H NMR, IR, MS, and elemental analysis. [ABSTRACT FROM AUTHOR]

A series of bis(1,2,4-triazole-3-thiols) 3a-d were prepared by condensation reactions of arylbis(carboxymethylthio)methanes 2a-d with thiocarbohydrazide. The starting diacids 2a-d were prepared by reactions of aromatic aldehydes 1a-d with thioglycolic acid. The structures of these newly synthesized compounds are characterized by elemental analysis, IR, and NMR spectroscopy. [ABSTRACT FROM AUTHOR]

C17H14N6S, orthorhombic, P212121 (no. 19), a = 7.3832(3) Å, b =14.4702(7) Å, c = 15.2806(7) Å, V = 1632.52(13) ų, Z = 4 and with Rint = 0.0577, Rgt(F) = 0.0358, wRref(F²) = 0.0944, T = 296(2) K. [ABSTRACT FROM AUTHOR]

C19H17BrN2O2, triclinic, P1̅ (no. 2), a = 8.3979(11) Å, b = 10.4083(14) Å, c = 11.1696(15) Å, α = 69.270(2)°, β = 89.401(2)°, γ = 73.709(2)°, V = 872.1(2) Å3, Z = 2, Rgt(F) = 0.0422, wRref(F2) = 0.1138, T = 296.15 K. [ABSTRACT FROM AUTHOR]