1,3,4,6-tetramethylpiperazine-2,5-dione was synthesized, and the crystal structure was characterized by single-crystal X-ray diffraction method, vibrational spectral measurements were obtained by Fourier transform infrared spectroscopy and Fourier transform Raman spectroscopy. The measurements agree well with the calculated geometrical structure and harmonic vibrational wavenumbers (usingab initio and density functional theory Becke’s three parameters hybrid method with the Lee, Yang, and Parr non-local functions methods with 6-311G and 6-311G** basis sets). 相似文献
Ketene dithioacetal derivatives, namely 3-[bis(methylthio)methylene] pentane-2,4-dione (1), 3-(1,3-dithian-2-ylidene) pentane-2,4-dione (2) and 3-(1,3-dithiolan-2-ylidene) pentane-2,4-dione (3) were synthesized and their respective capacity to inhibit copper corrosion in 3 M HNO3 was investigated by means of weight loss, potentiodynamic polarization, scanning electron microscopy (SEM) and energy dispersive X-ray fluorescence (XRF). The obtained results indicate that the addition of these compounds significantly decreases the corrosion rate. Potentiodynamic polarization studies clearly showed that the inhibition efficiency increases with increasing concentration of the investigated compounds at a fixed temperature, but decreases with increasing temperature. These results on the whole showed that the studied substances are good cathodic inhibitors for copper corrosion in nitric acid medium. SEM and energy dispersive X-ray (EDAX) examination of the copper surface revealed that these compounds prevented copper from corrosion by adsorption on its surface to form a protective film, which acts as a barrier to aggressive agents. The presence of these organic compounds adsorbed on the electrode surface was confirmed by XRF investigations. 相似文献
Two chemiluminescent compounds containing 2,5-di(thien-2-yl)pyrrole and pyridazine units, namely 5,7-di(thiophen-2-yl)-2,3-dihydro-1H-pyrrolo[3,4-d]pyridazine-1,4(6H)-dione (5) and 6-phenyl-5,7-di(thiophen-2-yl)-2,3-dihydro-1H-pyrrolo[3,4-d]pyridazine-1,4(6H)-dione (6), were successfully synthesized and electrochemically polymerized. The compounds have chemiluminescent properties and glow in the presence of hydrogen peroxide in basic medium. The intensity of the glow can be increased dramatically by using Fe3+ ions, hemin (1.0 ppm) or blood samples (1.0 ppm) as catalyst. The compounds 5 and 6 have one well-defined irreversible oxidation peak at 1.08 V and 1.33 V vs Ag/AgCl, respectively. Electrochemical polymerization of both 5 and 6 were carried out successfully by repeating potential scanning in the presence of BF3. Et2O in an electrolyte solution of 0.1 M LiClO4 dissolved in acetonitrile. The electronic band gaps (Eg) of the polymers P5 and P6 were found to be 2.02 eV and 2.16 eV, respectively. On the other hand, the corresponding polymers are electroactive and exhibited electrochromic features.
A model study of the interaction between biologically active bisquaternary
ammonium salts and their molecular targets in living systems is urgently
needed to elucidate the molecular mechanisms involved in the interactions
between these compounds. To address this need a combined
experimental-computational study of the interaction of two
tetramethylammonium cations (modeling two quaternary groups) with the
chlorine anion and with the deprotonated 2,5-dihydroxybenzoic acid (modeling
a carboxylic group and an aromatic ring of side radicals of proteins) has
been performed. Fast atom bombardment mass spectrometry method and
DFT/B3LYP/6-31++G** and MP2/6-31++G** calculations have been employed in the
study. Stable noncovalent complexes with different ratios of the
tetramethylammonium cations and chlorine anions or deprotonated
2,5-dihydroxybenzoic acid anions were registered in the mass spectra of
tetramethylammonium chloride and 2,5-dihydroxybenzoic acid mixture. This
finding shows that the organic and inorganic anions compete to bind
tetramethylammonium in the studied system. The theoretically determined
stabilities of the noncovalent complexes were compared with the relative
stabilities evaluated from the mass spectrometric measurements. The results
of the study allow us to elucidate the competing interactions that exist
between quaternary groups with inorganic counterions or with active groups
of molecular protein targets. 相似文献
Multicomponent reactions involving azines (phenanthridine or isoquinoline) and dimethyl acetylenedicarboxylate were undertaken in the presence of heterocyclic NH compounds (indole, 2-methyl indole, 3-methyl indole, carbazole and 3,6-dibromocarbazole) or 1,3-dicarbonyl compounds such as N,N'-dimethylbarbituric acid, 1,3-diethyl-2-thiobarbituric acid, acetylacetone, 1,3-diphenyl-1,3-propandione and cyclopentan-1,3-dione to generate enaminoesters in good yields. 相似文献
Poly (ADP-ribose) polymerase (PARP-1) is a well-established nuclear protein with prominent role in signaling and DNA repair. Various clinical candidates have been identified with the role in PARP-1 inhibition. Based on the pharmacophoric features identified from previous studies and molecular docking interactions, thiazolidine-2,4-dione derivatives have been evaluated for their PARP inhibitory activity. From an in vitro assay, 5-((1-(4-isopropylbenzyl)-1H-indol-3-yl)methylene)thiazolidine-2,4-dione (16) was identified as a potent inhibitor having low micromolar inhibitory activity \((\hbox {IC}_{50} \,{=}\, 0.74 \,\pm \, 0.25\,\upmu \hbox {M})\). Thus, a structure-based design approach utilized in the present study helped to identify thiazolidine-2,4-dione as a novel scaffold against PARP-1 for potential development of potent anticancer therapeutics. 相似文献
The quinazolin-2,4-dione moiety is found in many compounds with important biological activities making it a target for its synthesis. In this work, a one-pot three-step synthesis of new quinazolin-2,4-diones from phthalic anhydrides and their activity against Leishmania mexicana are described. The new quinazolin-2,4-diones were isolated with yields in the range of 32–70 %. All compounds displayed lower cytotoxicity in RAW 264.7 macrophage over miltefosine. Compound 6,7-dichloro-3-phenylquinazoline-2,4(1H,3H)-dione (6e) displayed an attractive profile which includes anti-Leishmania mexicana activity (\(\hbox {IC}_{50} = 6.05\)\(\upmu \)M), much lower cytotoxic activity (\(\hbox {CC}_{50} = 111\)\(\upmu \)M) and a high selective index (\(\text {SI} = 18.35\)) proving to be superior to miltefosine. 相似文献
