Synthesis and physicochemical properties of 9,10-phenanthrenequinone monoxime and its nitro derivatives

Phenanthrenequinone monoxime and its mono-, di-, and trinitro derivatives were synthesized. The acidity constants and their variation with the number and position of nitro groups were determined. The electronic and IR spectra of the nitro compounds were studied. The bands in the electronic spectra were assigned based on quantum-chemical calculations in the Pariser—Parr—Pople approximation. Correlations between the pK _a values and some calculated characteristics of the compounds under study were found. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1106–1110, June, 1999.     

Effect of the solvent nature and the number of electrophilic substituents in the molecule on hydration of nitro derivatives of phenanthrene-9,10-quinone

Solvates (1⩺2) of 10,10-dihydroxy-2,4,7-trinitro-9,10-dihydrophenanthren-9-one with DMSO and of 10,10-dihydroxy-2,7-dinitro-9,10-dihydrophenanthren-9-one with HMPA were prepared. The crystal structure of 2,5-dinitrophenanthrene-9,10-quinone was established. The results of X-ray diffraction analysis and IR spectroscopy of a series of mono-, di-, and trinitro derivatives of phenanthrene-9,10-quinone demonstrated that the ability of carbonyl groups to participate in nucleophilic addition of water increases as the number of nitro groups in substituted phenanthrene-9,10-quinone increases. The nature of the solvent (HMPA, DMF, or DMSO) affects hydration of phenanthrenequinones primarily due to the difference in the strength of intermolecular hydrogen bonds stabilizing di- and tetrahydroxy-dihydrophenanetherenes. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 738–742, April. 1999.     

Discovery and SAR exploration of <Emphasis Type="Italic">N</Emphasis>-aryl-<Emphasis Type="Italic">N</Emphasis>-(3-aryl-1,2,4-oxadiazol-5-yl)amines as potential therapeutic agents for prostate cancer

A new chemical series of antiproliferative compounds was identified via high-throughput screening on DU-145 human prostate carcinoma cell line (hit compound potency - 5.7 μM). Exploration of the two peripheral diversity vectors of the hit molecule in a hit-targeted library and testing of the resulting compounds led to SAR generalizations and identification of the 'best' pharmacophoric moieties. The latter were merged in a single compound that exhibited a 200-fold better potency than the original hit compound. Specific cancer cell cytotoxicity was confirmed for the most potent compounds.     

New Tetracyclic Spiro-1,2,4-trioxolanes (Ozonides). Synthesis and Mass Spectrometric Study

Russian Journal of Organic Chemistry - New tetracyclic dispiro-1,2,4-trioxolanes (ozonides) were synthesized by reactions of 5–7-membered alicyclic 1,5-diketones with 30% hydrogen peroxide in...     

Conductometric sensor with calixarene-based chemosensitive element for the arginine detection

A possibility of the creation of conductometric chemosensor with calixarene-based sensitive element for arginine detection was evaluated. The surface of gold interdigitated electrodes of conductometric transducer was modified with calixarene. The optimal concentration of calixarene for preparation of chemosensitive element was determined to be 100 mg/ml. The basic analytical characteristics of the developed chemosensor were determined (sensitivity to arginine—37.5 μS/mM, limit of arginine detection 5 μM, linear range 0.005–150 μM, response time 150 s) and analyzed as regards its application for arginine determination. It was established for all types of developed sensors that they have good reproducibility of signals to arginine over one working day; the measurement error (RSD) did not exceed 5%. The selectivity of calixarene-based chemosensor to arginine was investigated as well as the selectivity of calixarene complexation with arginine compared with other amino acids.     

Methods of synthesis of alicyclic 1,5,9-triketones. Reaction of transaminomethylation

Alicyclic 1,5,9-triketones with various combination of 5-, 6-, 7-membereded cycles in the molecule were obtained by methods of diketone condensation, Michael reaction, and proceeding from Mannich mono- and bisbases and cycloalkanones. The latter method was accompanied with a transaminomethylation, observed for the first time at triketones preparation. The structures of cyclic forms of Michael reaction products were refined.     

Reactivity of alicyclic 1,5,9-triketones toward five-, six-, and seven-membered rings in acidic medium. Stereochemistry of intramolecular cyclization products

Chemistry of Heterocyclic Compounds - Among nine alicyclic 1,5,9-triketones with differently fused 5-, 6-, and 7-membered rings in the molecule, existing as mixtures of 3–6 diastereomers,...