Synthesis of 3,4-dihydropyrimidin-2(1H)-one and 3,4-dihydropyrimidin-2(1H)-thione derivatives from aldehydes, 1,3-dicarbonyl derivatives and urea or thiourea using granite and quartz as new, natural and reusable catalysts. Some of the 3,4-dihydropyrimidin-2(1H)-thione derivatives were used to prepare new heterocyclic compounds. The antimicrobial activity of selected examples of the synthesized ...

High-resolution NMR spectroscopy for paramagnetic complexes in solids has been rarely performed because of its limited sensitivity and resolution due to large paramagnetic shifts and associated technical difficulties. The present study demonstrates that magic angle spinning (MAS) at speeds exceeding 20 kHz provides unusually high sensitivity and excellent resolution in 1H solid-state NMR (SSNMR...

Rare earth oxyhydrides REOxH(3–2x), with RE = Y, Sc, or Gd and a cationic FCC lattice, are reversibly photochromic in nature. It is known that structural details anion (O2–:H–) composition dictate the efficiency of behavior. The mechanism behind photochromism is, however, not yet understood. In this study, we use 1H, 2H, 17O, 89Y solid-state NMR spectroscopy density functional theory (DFT) calc...

The purpose of this work is the synthesis new isonicotinic acid hydrazones, study their structure, reactivity and biological screening some synthesized compounds. reactions leading to N-arylidene(alkylidene) hydrazones via condensation hydrazide with various derivatives aromatic aldehydes were studied. structure functionally substituted was established by FTIR, 1H 13C NMR, two-dimensional COSY ...

Two Cd complexes have been prepared by reaction of Cd (II) with 4-(1H-Tetrazol-5yloxy) – phenylamine (HTY) and 2-(1H-Tetrazol) pyridine (HTP) ligands. These new complexes were characterized by IR, UV-Visible, 1H-NMR and 13C-NMR spectroscopies. The changes observed between the FT-IR, H-NMR and UV-Vis spectra of the ligands and complexes allowed to establish the coordination mode of the metal in ...

The cycloaddition of 4-methoxycarbonyl-2(1H)-pyridones to silyloxydienes gave isoquinolone derivatives in reasonable yields. Furthermore, the cycloaddition of 6-methoxycarbonyl-2(1H)-pyridones to 2,3-dimethyl-1,3-butadiene produced cycloadducts (isoquinolone and quinolone derivatives) and double cycloadducts (phenanthridone derivatives). The activation energies using Gaussian 98 with RHF/3-21G ...

Substituted 3-(fluoroacyloxy)quinoline-2,4(1H,3H)-diones including 3-(fluoroiodoacetoxy) derivatives react with triethyl phosphite to afford either the product of the Perkow reaction or the corresponding 4-ethoxyquinolin-2(1H)-one. In both reactions, the fluorocarboxylate anion acts as the first observed leaving group. This observation restricts the application of the intramolecular Horner-Wads...

The microwave synthesis of quinoline alkaloid 4-methoxyquinolin-2(1H)-one 3a and its analogues 3b-e was achieved in 8-11 minutes by methoxydechlorinated of 4-chloroquinolin-2(1H)ones 2a-e using TBAB as phase transfer catalyst. The starting compound obtained by selective decholorination of 1a-e by sodium acetate/acetic acid and the structure of synthesized compound has been established by IR, 1H...

A series of 6-cyclic aliphatic amino-7-nitro-3,4-dihydroquinoline-2(1H)-ones were prepared and tested for platelet aggregation inhibitory effect, cardiotonic activity and chronotropic activity. These compounds appeared to show selective inhibitory activity against platelet aggregation. Among them, 6-(4-ethoxycarbonylpiperidino)-7-nitro-3,4-dihydroquinoline-2(1H)-one (22f) showed the most potent...

Cyclization of dipeptidyl chloromethyl ketones gave 6-(4-aminobutyl)-3-carboxyethyl-5-methyl-2(1H)-pyrazinone, 3-(4-aminobutyl)-6-carboxyethyl-5-methyl-2(1H)-pyrazinone, and 3,6-bis(4-aminobutyl)-5-methyl-2(1H)-pyrazinone, which were inserted into the enkephalin sequence to give opioid mimetics. Thus, it was confirmed that a pyrazinone ring can be easily inserted into a peptide sequence in orde...