Organic Communications Articles

IIn the present review, we discuss new and diverse methods for synthesizing chromene, coumarin, pyrimidine, pyridine, pyrazole, thiazole and thiophene derivatives from 1,3-diketones, according to Knoevenagel condensation, Michael addition, Hantzsch reaction, and Gewald’s reaction. Various catalysts and reagents were used to complete the cyclization processes. Most of the produced compounds showed remarkable activity against different types of cancer cell lines and toward Gram-negative and Gram-positive bacteria. Furthermore, anti-quorum sensing, in vitro COX-1 and COX-2 enzymatic inhibition assays were evalua

Potentiometric methods are a type of electrochemical analysis which are used widely in many applications due to their multiple advantages such as wide concentration range, low detection limit, high selectivity, and sensitivity. Potentiometric sensors have many advantages over the other analytical methods and have been successfully applied in different real sample analyzes. Crown ethers are a group of macrocyclic compounds and have been used as ionophores by researchers due to their favorable chemical structures. In this review, we provide a description on crown ethers used as ionophores in potentiometric sensors.

TThis paper describes novel agro-waste derived Water Extract of Orange Fruit Shell Ash (WEOFSA) catalyzed synthesis of 5-aryl-1,2,4-triazolidine-3-thiones and 1,2,4-triazospiro-3-thiones under microwave irradiation. Herein, we have developed inexpensive, facile and green method synthesis of cyclic thiones by the reaction of aromatic aldehyde and cyclic ketone, with thiosemicarbazide in presence of agro-waste derived catalyst. The obtained product is chromatographically pure after recrystallization from ethanol, and final product is characterized by various spectroscopic techniques FT-IR, 1H-, 13C-NMR and HR-MS.

Novel monopeptide-anthraquinone conjugates (1-16) were synthesized by the reaction of appropriate N-protected amino acid with 2-hydroxymethylanthraquinone in good or high yields. The structural elucidation of the new compounds was accomplished by 1H-NMR, 13C-NMR, MS, FT-IR spectroscopy and elemental analysis techniques. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activity of the new compounds was determined against two human (h) isoforms, hCA I and hCA II. While three of the sixteen compounds showed moderate in vitro carbonic anhydrase inhibitory properties against hCA II with inhibition constants in the micromolar level (43.5, 67.4 and 78.1 µM), they did not show inhibitory activity against hCA I up to 100 µM concentration. The antioxidant abilities of the compounds were determined using the 1,1-diphenyl-2-picrylhydrazil (DPPH) radical scavenging method, ferric ion reducing assay and metal chelation methods. While a small amount of antioxidant activity was observed according to the DPPH and ferric ion reducing power assay methods, none of the compounds showed antioxidant properties according to the metal chelating activity method at the concentrations studied.

The carbazole skeleton is the key structural motif of many bioactive molecules including synthetic and natural products. The carbazole derivatives bearing different functional groups have important pharmacological activities and are widely used in medicine and pharmacology. Ethyl 9H-carbazol-9-yl acetate was synthesized from the reaction of the carbazole with ethyl bromoacetate. The acetate ester derivative was converted into the 2-(9H-carbazol-9-yl) acetohydrazide through treatment with hydrazine hydrate. The target compounds were synthesized by using carbazole-hydrazide compound and various aromatic acid chlorides. Acetyl benzohydrazide derivatives were prepared from the nucleophilic addition-elimination reactions of corresponding benzoyl chloride and 2-(9H-carbazol-9-yl) acetohydrazide in THF at room temperature condition. The structures of all newly synthesized compounds were characterized using different spectroscopic techniques, such as FT-IR, 1H NMR, 13C NMR, and HRMS.    The urease enzyme activities of these compounds were investigated using Jack bean urease as the model enzyme.

In the 20th century, many new drugs have been designed and synthesized to be used for therapeutic purposes. In these syntheses, especially the salicylic acid group is included in the structure of many drugs. The salicylic acid molecule is the starting material of aspirin and is a structurally important compound. There are many commercial products on the market that are synthesized from salicylic acid or contain salicylic acid group. In this study, the synthesis of salicylic acid-pyrrolone hybrid compounds was carried out from the reactions of furan-3-one compounds with 4-aminosalicylic acid and 5-aminosalicylic acid reagents. The synthesis reactions were achieved in three steps and in these synthesis biologically active pyrrolone and salicylic acid groups were integrated. The characterizations of these compounds that were purified by column chromatography and crystallization method were made by FTIR, NMR and HRMS techniques. The cytotoxic and genotoxic potentials of the novel compounds (7a-e) were evaluated at five different concentrations (6.25, 12.5, 25, 50 and 100 μM) using the Allium test system. As a result of cytogenetic analysis, it was determined that high concentrations of some hybrid compounds significantly reduced the number of divisions of A. cepa cells (cytotoxicity in 7a and 7c) and caused chromosomal abnormalities in dividing cells (genotoxicity in 7a, 7c, 7e, and especially 7d).

N,N′-Dicyclohexylcarbodiimide  and hydroxybenzotriazole  mediated amination of free COOH group of N-tert-butyloxyoxycarbonyl-L-isoleucine 1 with three aromatic amines  gave the corresponding  amides 2a-c.  Deprotection of N-tert- butyloxyoxycarbonyl groups of 2a-c with AcOH yielded the related amine derivatives 3a-c. The amidation of the free NH2 groups of (3a-c) with phthaloyl dichloride yielded the bis-amide products 4a-c. The synthesized compounds were purified by crystallization and their structures were elucidated by spectroscopic methods such as 1H-HMR, 13C-NMR, FTIR, and micro analysis.

The porous poly(2-naphthol) was made-up by combining the 2-naphthol, dimethoxymethane as an cross linker in presence of FeCl3. Furthermore the polymer was functionalized with ClSO3H to get a dense acid catalyst. The reagent is active for benzylation of arenes with benzylic alcohols irrespective of the nature of substituted arenes. This catalyst is good active compared with other acid catalyst used for Friedel−Crafts benzylation.