Letters in Organic Chemistry - Volume 12, Issue 9, 2015

A series of thienylchalcones with fluoro and trifluoromethyl derivatives were synthesized and evaluated for their capability to inhibit human monoamine oxidase A and B. The chemical structures of the compounds have been ascertained by means of their 1HNMR, 13CNMR, mass spectroscopic data and elemental analysis. The results documented that these compounds revealed moderate to good inhibitory activiti Read More

The synthesis of steroid-benzenacyclononaphanone was performed using some chemical tools. In the first stage, an indol-pregnenolone derivative (3) was prepared by the reaction of pregnenolone with phenylhydrazine. Additionally, the compound 3 was bound to ethylenediamine to form a new indol-pregnenolone derivative (4). The third stage was achieved by synthesis of a benzamide derivative (6) by the reaction of 4 with Read More

Enantiospecific and enantioselective approaches to the natural (16R,19R)- and the unnatural (16S,19S)- THF core of the bioactive acetogenin annonacin are described which utilizes both a chiral pool synthesis and enzymatic transformations. In the antipodal (2S,5S) THF series derived from D- (+)-glucosamine, the semi-protected THF aldehyde synthon allows for two-directional synthetic elaboration through a Henry reaction Read More

A new series of 1,2-disubstituted 4-phenylurazoles have been synthesized with aza-Michael addition of 4-phenylurazole and different acrylic esters. It was found that, without basic media, no reaction took place and the reactions proceeded easily in tetrabutylammonium bromide (TBAB), an ionic organic salt, under solvent-free conditions. The reactions were performed efficiently using 1,4- diaza-bicyclo[2,2,2]octane (DABCO), as a Read More

Acyl / sulfonyl hydrazines were synthesized in a one-pot reaction from carboxylic acid/aryl sulfonic acid in the presence of 1,1-carbonyl diimidazole (CDI) under ultrasound as well as under conventional heating. The reaction was performed on diverse organic molecules including simple benzoic acid (1), electron-donating and electron-withdrawing substituted benzoic acids, biologically active compounds like coumarin-3-carboxylic Read More

Potassium fluoride-clinoptilolite, which is prepared from commercially available and cheap starting materials, was used as an efficient and recyclable catalyst for Knoevenagel condensation of aromatic aldehydes with active methylene compounds under ultrasound irradiation. Short reaction times, high yields of products, ease of recovery and catalyst reusability make this new method economic and efficient.

One-pot three component reaction of various types of aldehydes, dimedone, ammonium acetate and active methylene compounds was carried out in the presence of MCM-41 functionalized with B-F bonds nanostructured catalyst for the synthesis of polyhydroquinolines. MCM-41 was prepared by Sol-Gel method under mild conditions and B-F functionalized MCM-41 with various loading amounts of boron/fluoride were prepared and Read More

13C and 15N isotope labeled precursors and 6-amino-2,3-dimethylpyrimido[4,5-e][1,2,4] triazine-8-one were synthesized for the mechanistic study of dihydropteridine reductase (DHPR). Structures of precursors and the inhibitors were confirmed by UV/Vis, 13C NMR, and ESI-MS measurements.

An optically active poly(hydrazide-imide) (PHI) containing L-lysine was prepared by interfacial polycondensation. The corresponding polymeric nanocomposites have been prepared using multi-walled carbon nanotube (MWCNT) through sonication. Crystallization was studied by DSC (Differential scanning calorimetry) technique. Incorporation of nanotubes into the polymeric matrix improved the mechanical properties Read More

This paper focuses on the synthesis of a wide variety of di benzo spiro bis-crown compounds, in good yields using di-phenols, mono tosylates of oligoethylene glycols and caesium carbonate in acetonitrile.

New quaternary alkylammonium conjugates of steroids were obtained by two step reaction of methyl esters of bile acids with bromoacetic acid bromide, followed by bimolecular nucleophilic substitution with a long chain tertiary alkylamine. The structures of products were confirmed by spectroscopic (1H-NMR, 13C-NMR, and FT-IR) analysis, mass spectrometry (ESI-MS) as well as PM5 semiempirical methods. The biologic Read More