Synthesis of new 1,2,3-triazolo-nucleoside analogues with 2-propargylamino pyrimidines via click reactions.

In this study, it was reported that twelve nucleoside analogues were synthesized by click reactions. The reactions were carried out between the azide derivatives of D-glucopyranose, D-galactopyranose, D-ribofuranose and 2-propargylamino pyrimidine derivatives (5 and 7) that are synthesized via a different route for the first time. In the first step, N-propargyl guanidine was obtained with the reaction of 1H-pyrazole-1-carboxamidine hydrochloride and propargyl amine, then condensation of N-propargyl guanidine and ß-diketone (4 and 6) resulted in 2-propargylamino pyrimidines (5 and 7) for the first time in good yields (85%). Finally, click reactions were performed with azidosugars (8a-8f) and 2-propargylamino pyrimidine derivatives and produced twelve new nucleoside analogues in good yields. (9a-9f, 10a-10f, 65-73% yields). The chemical structures of the new derivatives were elucidated spectroscopic techniques, such as FT-IR, 1H NMR, 19F NMR, 13C NMR and TOF-ESI-MS.

First determination of some phenolic compounds and antimicrobial activities of Geranium ibericum subsp. jubatum: A plant endemic to Turkey.

This paper includes the results of the first study about the phenolic characteristics and antimicrobial analyses of Geranium ibericum subsp. jubatum species found in Turkey . In the present work, the phenolic contents of different parts of the G. ibericum (flower, root, leaf) were determined with high-performance liquid chromatography (HPLC)-DAD (diode-array detector) and liquid chromatography (LC)-MS/MS (mass spectrometry). The following phenolic compounds were investigated: catechin, protocatechuic acid, gallic acid, ellagic acid, chlorogenic acid, 4-hydroxybenzaldehyde, p -coumaric acid, rutin, naringenin, kaempferol . Based on the results obtained, the roots and flowers of the plant are found to be very rich in ellagic acid (3473.57 µg g-1 dry plant) and catechin (2228.76 µg g-1 dry plant). The amount of chlorogenic acid (54.570 µg g-1 dry plant) is also high in the roots. The amounts of protocatechuic acid (122.5 µg g-1 dry plant) and gallic acid (725.34 µg g-1 dry plant) are high in the leaves. In addition, the total extract of G. ibericum obtained from leaf, flower, and root was tested against 6 gram-negative bacteria and Candida albicans . The G. ibericum extract was nearly as effective as commercial antibiotics at some concentrations (500-750 µg µL-1) for Acinetobacter baumannii , Klebsiella pneumonia , Proteus mirabilis , and Bacillus cereus .

Syntheses of 1,2,3-triazole-bridged pyranose sugars with purine and pyrimidine nucleobases and evaluation of their anticancer potential.

With the aim to create a library of compounds with potential bioactivities by combining special characteristics of two important groups such as nucleobases and carbohydrates, twenty 1,4-disubstituted-triazole nucleosides were synthesized in good yields (80-94%) using the copper catalyzed 'Click' reaction between azido-modified pento- or hexopyranoses and alkyne-bearing pyrimidine or purine nucleobases. Structural elucidation was made with the assistance of spectroscopic techniques such as FTIR, 1D-, 2D-NMR, and ESI-TOFMS. All the synthesized triazole nucleosides were evaluated for their cytotoxic activity against three human cancer cell lines (MDA-MB-231, Hep3B, PC-3) by using the MTT assay. Particularly, compounds 3a and 1b were identified as potential hits against Hep3B cell.

Synthesis, characterization and non-isothermal decomposition kinetic of a new galactochloralose based polymer.

A glycopolymer, poly(3-O-methacroyl-5,6-O-isopropylidene-1,2-O-(S)-trichloroethylidene-α-d-galactofuranose) (PMIPTEG) was synthesized from the sugar-carrying methacrylate monomer, 3-O-methacroyl-5,6-O-isopropylidene-1,2-O-(S)-trichloroethylidene-α-d-galactofuranose (MIPTEG) via conventional free radical polymerization with AIBN in 1,4-dioxane. The structures of glycomonomer and their polymers were confirmed by UV-vis, FT-IR, (1)H NMR, (13)C NMR, GPC, TG/DTG-DTA, DSC, and SEM techniques. SEM images showed that PMIPTEG had a straight-chain length structure. On the other hand, the thermal decomposition kinetics of polymer were investigated by means of thermogravimetric analysis in dynamic nitrogen atmosphere at different heating rates. The apparent activation energies for thermal decomposition of the PMIPTEG were calculated using the Kissinger, Kim-Park, Tang, Flynn-Wall-Ozawa (FWO), Kissinger-Akahira-Sunose (KAS) and Friedman methods and were found to be 100.15, 104.40, 102.0, 102.2, 103.2 and 99.6 kJ/mol, respectively. The most likely process mechanism related to the thermal decomposition stage of PMIPTEG was determined to be a Dn deceleration type in terms of master plots results.

The Knoevenagel-Doebner reaction on 1,2-O-(2,2,2-trichloroethylidene) derivatives of D-gluco- and D-manno-furanose.

The synthesis of new α,ß-unsaturated furanuronic acid derivatives of α-gluco-, ß-gluco- and ß-manno-chloraloses via a convenient one pot procedure using the Knoevenagel-Doebner reaction approach are described. The dialdofuranose derivatives were reacted with malonic acid under Knoevenagel-Doebner reaction conditions and (E)-α,ß-unsaturated furanuronic acid derivatives were obtained.

Determination of some chemical parameters and antimicrobial activity of traditional food: mesir paste.

The antimicrobial activities and some chemical properties of the traditional Turkish food called mesir paste were studied. Results of chemical analysis for moisture and volatiles, water-insoluble components, refractive index, soluble solids content, raw fiber, invert sugar, total ash, 5-hydroxymethylfurfural, acidity, and pH were calculated as 17.06%, 2.55%, 1.491, 80.2%, 0.70%, 40.54%, 0.13%, 44 mg/kg, 0.9% anhydrous citric acid, and 3.6, respectively. Mesir paste was extracted individually by six solvents with different polarity, and antimicrobial activities of each extracts were determined against 12 microbial strains, mostly food-borne, including pathogens, by the agar well diffusion method. All extracts obtained showed antimicrobial activity ranging from 8 mm to 40 mm, and the butanolic extract displayed stronger antimicrobial activity against all tested microorganisms; Gram-positive strains were found to be more sensitive than Gram-negative strains. Antimicrobial potency of n-butanol extracts of mesir paste was determined in term of minimal inhibitory concentration and minimal bactericidal concentration for the sensitive microorganisms. In addition, some commercial antibiotics such as ampicillin, gentamicin, and nystatin were used as positive controls to determine the sensitivity of the strains.

Synthesis and antimicrobial activities of two novel amino sugars derived from chloraloses.

The synthesis of 5-amino-5-deoxy-1,2-O-(S)-trichloroethylidene-beta-L-arabinofuranose and 6-amino-6-deoxy-1,2-O-(S)-trichloroethylidene-alpha-D-glucofuranose is described by a simple three- or four-step route. Antibacterial potency of the new compounds was determined using an inhibition zone diameter test. The results show that these compounds have a broad-spectrum activity against Gram-positive, Gram-negative bacteria and Candida albicans.