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The analyses of Tc-DMSA complexes prepared under alkali and acidic reactions were reported. Modern analytical, separation and spectral methods such as NMR (H-NMR, C-NMR, APT, COSY and HSQC) and Q-TOF HPLC-MS/MS system with ESI were employed to determine the identity and characterization of the products. The structure of Tc(V)DMSA was clearly confirmed and its fragmentation path in negative and positive ionisation mode was suggested. The effect of ascorbic acid and new alternative labelling with the use of NHTcOCl was examined. Surprisingly, Tc(III)DMSA complex was not formed under acidic reaction conditions. Tc(V)DMSA complex was the main reaction product under both experimental conditions. This result suggests the key role of Tc concentration during the process of radiopharmaceuticals preparation. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Monthly / Monatshefte für Chemie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemical Monthly / Monatshefte für Chemie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tumor transformation of the human brain cells causes different biochemical changes. Here we employed [sup 1]H magnetic resonance spectroscopy to compare the presence of low molecular weight metabolites in meningeoma and astrocytoma tumors by measuring perchloric acid extracts of the cells. In [sup 1]H spectra of meningeoma we detected high signal from lactate but were unable to detect any signal of NAA and creatine. In contrast, astrocytoma samples revealed significantly higher level of inositol and glycine and significant decrease in glutamate and glutamine compared with meningeoma but no presence of taurine. Our results suggest that [sup 1]H MRS can provide useful information about biochemical changes in different types of brain tumors. Acknowledgements: This work was supported by the Grant Category C and Comenius University Grant No. X/2003. [ABSTRACT FROM AUTHOR]

The article presents an abstract of the research paper " 1H MR Spectroscopy Study Of The Human Meningiomas And Astrocytomas In Vitro." As tumors have varied metabolism and disordered physiology, the differences in magnetic resonance spectra can be observed. 1H MRS of brain tumors show changes in the relative resonance intensities of chemical compounds normally observed in the spectrum, while the new compound signals can be obtained from neutral lipids, alanine, et al.

The stereoselective synthesis of epi -thieno analogues of the phenanthroquinolizidine bioactive alkaloids (-)-Cryptopleurine and (-)-(15 R )-Hydroxycryptopleurine was achieved in five steps starting from easily available enantiopure ( S )-2-aminoadipic acid used as chiral pool and nitrogen atom source. During these investigations, both π-cationic cyclization of chiral N -thienylmethyl-6-oxopipecolinic acids into pure ( S )-keto-lactams and theirs regioselective and diastereoselective reduction, considered as key steps of this sequence, were studied. Of particular interest, the Friedel-Crafts cyclization using (CF 3 CO) 2 O/BF 3 ·Et 2 O show that near the expected keto-lactams, enamides and enamidones containing trifluoromethyl residue were isolated. A mechanism leading to the latter products with high synthetic potential was discussed., (© 2016 Published by Elsevier Ltd.)

Cyclohexadepsipetides enniatin B, B1 and G were isolated from the cultivation broth of Fusarium dimerum Penzig, an endophyte of Magnolia x soulangeana. Their production was about 350 mg l(-1) after 96 h of submerged cultivation in Sabouraud maltose medium. Isolated enniatins inhibited growth of selected microorganisms and activity of 12-lipoxygenase with IC50 = 0.73 mg l(-1).

The antiradical activity, protective effect against lipid peroxidation of liposomal membrane, and inhibitory effect on whole blood reactive oxygen species (ROS) liberation of Glycyrrhiza glabra crude extract and glycyrrhizin, its major compound, were assessed. The liquorice extract showed significant activity in all the three assay systems used in a dose dependent manner. It displayed remarkable reactivity with free stable 1,1'-diphenyl-2-picrylhydrazyl (DPPH) radical, inhibitory efficacy in peroxidatively damaged unilamellar dioleoyl phosphatidylcholine (DOPC) liposomes, and inhibition of ROS chemiluminescence, generated by whole blood, induced by both receptor-bypassing stimuli (PMA) and receptor operating stimuli (Opz) in the ranking order of stimuli PMA> Opz. These activities may be attributed to phenolic antioxidants involving isoflavan derivatives, coumarins and chalcones. Nonetheless, triterpene saponin glycyrrhizin exhibited no efficacy in the system of DPPH reaction and peroxidation of liposomal membrane, and negligible inhibition of chemiluminescence generated by inflammatory cells. These results indicate that the mechanism of anti-inflammatory effect of glycyrrhizin most probably does not involve ROS and this major constituent is not responsible for the inhibition effects of liquorice extract on neutrophil functions.

Chiral beta-cyclodextrin was used to separate diazepam conformers. Several mobile phases of the composition acetonitrile/acetate buffer 200 mmol/l (pH=3.3, 5.5, 6.5) were employed for this purpose. As follows, the influence of addition of chiral beta-cyclodextrin to the mobile phase on diazepam separation was studied. The interconversion was a concurrence process of separation, resulting from stereolability of the diazepam molecule. The influences of temperature, flow rate, pH, and ionic strength of the mobile phase on interconversion and chromatographic parameters (retention factor and selectivity coefficient) were studied. Complementary off-line NMR measurements were carried out with the goal to confirm the structure of diazepam in the presence of an acid mobile phase.

The stability constants of the 1:1 complexes formed between methylphosphonylphosphate (MePP(3-)), CH(3)P(O)(-) (2)-O-PO3(2-), and Mg(2+), Ca(2+), Sr(2+), Ba(2+), Mn(2+), Co(2+), Ni(2+), Cu(2+), Zn(2+), or Cd(2+) (M(2+)) were determined by potentiometric pH titration in aqueous solution (25 degrees C; l = 0.1 M, NaNO(3)). Monoprotonated M(H;MePP) complexes play only a minor role. Based on previously established correlations for M(2+)-diphosphate monoester complex-stabilities and diphosphate monoester beta-group. basicities, it is shown that the M(Mepp)(-) complexes for Mg(2+) and the ions of the second half of the 3d series, including Zn(2+) and Cd(2+), are on average by about 0.15 log unit more stable than is expected based on the basicity of the terminal phosphate group in MePP(3-). In contrast, Ba(Mepp)(-) and Sr(Mepp)(-) are slightly less stable, whereas the stability for Ca(Mepp)(-) is as expected, based on the mentioned correlation. The indicated increased stabilities are explained by an increased basicity of the phosphonyl group compared to that of a phosphoryl one. For the complexes of the alkaline earth ions, especially for Ba(2+), it is suggested that outersphere complexation occurs to some extent. However, overall the M(Mepp)(-) complexes behave rather as expected for a diphosphate monoester ligand.

1H-nuclear magnetic resonance spectroscopy was used to study malignant melanoma extract. The aim of this work was to study low molecular weight metabolites soluble in water, which can be helpful for a more detailed understanding of tumor metabolism with a view to using this knowledge for diagnosis. The authors found in a well distinguished spectrum the presence of numerous low molecular weight metabolites such as glutamate, glutamine, choline, inositol, creatine, phosphocreatine, phosphocholine, glucose, acetate, alanine, lactate. It is necessary to correlate these in-vitro findings with a study of the above mentioned metabolites in-vivo. Malignant melanoma is appropriate for this investigative and diagnostic technique because of its superficial localization. (Fig. 1, Ref. 18.)