The series of eight substituted amides of 5-hydroxy-2-methylquinoline-7-carboxylic acid were prepared. The synthetic procedures of the compounds are presented. All the prepared quinoline derivatives were analyzed using RP-HPLC method for the lipophilicity measurement and their lipophilicity was determined. The prepared compounds were tested for their photosynthesis-inhibiting activity (the inhibition of photosynthetic electron transport in spinach chloroplasts (Spinacia oleracea L.) and the reduction of chlorophyll content in (Chlorella vulgaris Beij.). Several compounds showed the biological activity comparable with or higher than the standard 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). The relationships between the lipophilicity and the chemical structure of the studied compounds are discussed as well as the structure-activity relationships (SAR) between the chemical structure and the biological activities of the evaluated compounds.

Some 5-arylalkylidene-2-thioxo-1,3-thiazolidine-4-one derivatives were prepared as potential antimicrobial compounds. General synthetic approach of all newly synthesized compounds is presented. All the discussed rhodanine derivatives were analyzed using the reversed phase high performance liquid chromatography (RP-HPLC) method for the lipophilicity measurement. The procedure was performed under isocratic conditions with methanol as an organic modifier in the mobile phase using end-capped non-polar C18 stationary RP column. In the present study the correlation between RP-HPLC retention parameter log K (the logarithm of capacity factor K) and log P values calculated in various ways is discussed as well as the relationships between the lipophilicity and chemical structure of the studied compounds.

The mechanism of formation of coumarin (1) by Perkin reaction from salicylaldehyde was shown to involve exclusively a basecatalyzed intramolecular aldol-type condensation of O-acetyl salicylaldehyde (2) as an obligatory intermediate followed by dehydration. Direct evidence in support of this contention was provided by the formation of coumarin and 3-phenyl coumarin(5) as the sole products in the reactions of O-acetyl salicylaldehyde(2)with Et3N or NaOAc and O-α-phenyl acetyl salicylaldehyde (4) with Et3N, respectively. A novel synthesis of 1,1-diphenyl-2(2'-hydroxyphenyl)ethene(8a) was achieved by the reaction of O-α,α-diphenylacetylsalicylaldehyde (6) with Et3N. A plausible mechanism of formation of 8a in the above reaction is proposed. The formation of 8a is assumed to involve an intermediate β-lactone (9) formed through two consecutive intramolecular condensation. Base-catalyzed decarboxylation of 9 finally gives 8a.

CuO/MgO system having different extent of CuO varying between 0.025 to 0.3 mol/mol MgO were prepared by impregnation method followed by calcination at 400-800 ºC. The effect of CuO content, calcination temperature and doping with small amounts of K2O (1-3 mol % )on physicochemical surface and catalytic properties of the system have been investigated using XRD, adsorption of N2 at -196ºC, and catalytic conversion of isopropyl alcohol at 150-400 ºC using a flow technique. The results revealed that the solids having formula 0.2 and 0.3 CuO/MgO calcined at 400 consisted of MgO and CuO as major phases together with Cu2O as minor phase. The degree of crystallinity and crystallite size increase by increasing the calcination temperature within 400-800 ºC. The BETsurface areas of different adsorbents decreased progressively as a function of CuO loading and calcination temperature. Furthermore, K2O-doping decreased the degree of crystallinity of CuO phase present with subsequent increase in the crystallite size of MgO from 23 to 37.5 nm in case of solid having the formula 0.2 CuO / MgO calcined at 400 ºC. MgO-support material showed very small catalytic activity in isopropyl alcohol conversion. The investigated system behaved as selective catalyst for dehydrogenation of isopropyl alcohol with selectivity > 80%. The catalytic activity increases progressively as a function of extent of loading and decreases by increasing calcination temperature above 400 ºC. K2O- doping much increases the catalytic activity.

Fluorescent conjugates of N-benzyloxycarbonyl protected γ-aminobutyric acid (GABA) were prepared by coupling to its C-terminus several polyheteroaromatic labels, based on the pyran ring. Photophysical properties were evaluated and the results showed that these GABA conjugates presented strong fluorescence with maximum emission wavelengths between 393 and 503 nm, as well as high fluorescence quantum yields in ethanol.

A new, simple and one-step method used for synthesis of new compound tetramethylammonium pentachlorofluororhenate- (V) in very high yield. This compound one of the mixed halo complexes of rhenium that have been prepared by the reaction between tetramethylammonium fluoride and ReCl5 in 1:1 molar ratio in the minimum amount of dry acetonitrile. The compound has been characterized by elemental analyses and IR spectral studies.

Reduction of different aldehydes and ketones were efficiently accomplished by sodium borohydride in a ball-mill under solvent-free conditions.

An effective methodology for the quantitative preparation of phenylhydrazones and 2,4-dinitrophenylhydrazones from aldehydes and ketones is described. The method is environmentally friendly and easy to handle, while requires short reaction times and solventless conditions.

The goal of this project was to investigate the feasibility of a new one-pot synthetic protocol.

A combination of tetrachlorosilane and sodium sulphide in acetonitrile was found to be an efficient thionating reagent for aromatic aldehydes giving the corresponding thioaldehydes as trimers in good yields as well as for α,β-unsaturated ketones under the catalysis of cobalt(II) chloride giving β-mercaptoketones that subsequently auto-oxidized yielding the respective disulfides in moderate yields at ambient temperature. No reaction was observed with aryl methyl ketones.