• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.594-602
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• 2011

The effect of ${\alpha}$-, ${\beta}$- and ${\gamma}$-picolines on the stereochemistry of the coordination compounds of lanthanide(III) nitrates derived from 4[N-(furfural)amino]antipyrine semicarbazone (FFAAPS) has been studied. The general composition of the present coordination compounds is [Ln(FFAAPS)$(NO_3)_3$Pic] (Ln=La, Pr, Nd, Sm, Gd, Tb, Dy or Ho and Pic=${\alpha}$-, ${\beta}$- or ${\gamma}$-picolines). All these coordination compounds have been characterized by elemental analyses, molecular weight, molar conductance, magnetic susceptibility, infrared and electronic spectra. The infrared studies suggest that the FFAAPS behaves as a neutral tridentate ligand with N, N, O donor while ${\alpha}$-, ${\beta}$- or ${\gamma}$-picoline is coordinated to the lanthanide(III) ions via heterocyclic N-atom. Nitrates are bicovalently bonded in these compounds. From the electronic spectral data, nephelauxetic effect (${\beta}$), covalence factor ($b^{1/2}$), Sinha parameter (${\delta}%$) and the covalence angular overlap parameter (${\eta}$) have been calculated. Thermal stabilities of these complexes have been studied by thermogravimetric analysis. The coordination number of lanthanide(III) ions in the present compound is found to be ten. The antibacterial studies screening of the primary ligand FFAAPS and the complexes showed that the present complexes have moderate antibacterial activities.

• Archives of Pharmacal Research
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• v.21 no.4
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• pp.465-469
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• 1998

The search for platinum (II)-based compounds with improved therapeutic properties was prompted to design and synthesize a new family of water-soluble, third generation cis-diaminedichloroplatinum (II) complexes linked to uracil and uridine. Six heretofore unreported uracil and uridine-platinum (II) complexes are; [N-(uracil-5-yl-methyl)ethane-1,2-di-amine]dichloroplatinum (II) (3a), [N-(uracil-6-yl-methyl)ethane-1,2-diaminel dichloroplatinum (II) (3b), t[N-($2^1$, $3^1$,$5^1$-tri-O-acetyl)uridine-5-yl-methyl] ethane-1,2-diamineldichloroplatinum (II) (6a), {[N-($2^1$,$3^1$, $5^1$-tri-O-acetyl) uridine-6-yl-methyl]ethane-1,2-diamine)dichloroplatinum (II) (6b),[N-(uridine- 5-yl-methyl)ethane-1,2-diamine]dichloroplatinum (II) (7a), [N-(uridine-6-yl- methyl)ethane-1,2-diamine]dichloroplatinum (II) (7b). These analogues were prepared from the key starting materials, 5-chloromethyluracil (1a) and 6-chloromethyluracil (1b) which were reacted with ethylenediamine to afford the respective 5-[(2-aminoethyl)aminol methyluracil (2a) and 6-[(2-aminoethyl)amino]methyluracil (2b). The cis-platin complexes 3a and 3b were obtained through the reaction of the respective 2a and 2b with potassium tetrachloroplatinate (II). The heterocyclic nucleic acid bases 1a and 1b were efficiently introduced on the .betha.-D-ribose ring via a Vorbruggen-type nucleoside coupling procedure with hexamethyldisilazane, trimethylchlorosilane and stannic chloride under anhydrous acetonitrile to yield the stereospecific .betha.-anomeric 5-chloromethyl- $2^1$,$3^1$,$5^1$-tri-O-acetyluridine (4a) and 6-chloromethyl-$2^1$,$3^1$,$5^1$-tri-O-acetyluridine (4b), respectively. The nucleosides 4a and 4b were coupled with ethylenediamine to provide the respective 5-[(amino-ethyl)aminolmethyl-$2^1$,$3^1$,$5^1$-tri-O-acetyluridine (5a) and 6-[(aminoethyl)amino] methyl-$2^1$,$3^1$,$5^1$-tri-O-acetyluridine (5b). The diamino-uridines 5a and 5b were reacted with potassium tetrachloroplatinate (II) to give the novel nucleoside complexes, 6a and 6b, respectively which were deacetylated into the free nucleosides, 7a and 7b by the treatment with CH$_{3}$ONa. The cytotoxic activities were evaluated against three cell lines (FM-3A, P-388 and J-82) and none of the synthesized compounds showed any significant activity.

• Journal of Food Hygiene and Safety
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• v.36 no.3
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• pp.213-219
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• 2021

Hazardous substances are formed during food manufacturing, processing, or cooking, and may pose a threat to food safety. Here, we present a dietary exposure assessment of Korean consumer's intake of hazardous materials through a Total Diet Study (TDS) which was conducted by the Ministry of Food and Drug Safety (MFDS). The levels of exposure to materials such as acrylamide, furan, biogenic amines, etc., were estimated and risk assessments were then performed. Acrylamide and furan were selected as hazards with high priority of reduction control due to their having a margin of exposure (MOE) lower than 10,000. Risk assessment of exposure to ethyl carbamate, benzene and 3-MCPD showed MOEs higher than 100,000, indicating "safe". Dietary exposure to polycyclic aromatic hydrocarbons and benzopyrene was also found to be safe MOE levels >10,000. In addition, the results indicated safe MOEs (>1,000,000) for heterocyclic amines, nitrosamines, and biogenic amines. Most of the potential food contaminants were being kept at safe levels, however, it is necessary to continue to monitor and control exposure levels in accordance with the 'as low as reasonably achievable' (ALARA) principle.

• Korean Journal of Soil Science and Fertilizer
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• v.11 no.3
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• pp.127-144
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• 1979

Recent trend in the studies on the forming processes, chemical characteristics and chemical structure of humic substances with some discussions are reviewed and some arguments for the elucidation of the chemical structure of humic substances are summarized.