A new easy approach to separation of dopamine hydrochloride is reported. The molecularly imprinted polymer (MIP) was used as the adsorbent material. The MIP was prepared employing dopamine hydrochloride as a template and methacrylic acid (MAA) with ethylene glycol dimethacrylate (EDMA) in co-polymerization process. Non-covalent prearrangement between dopamine hydrochloride and methacrylic acid in organic porogen prior to bulk polymerization was utilized. Preliminary chromatographic results showed that dopamine hydrochloride could be retained by the polymer and then eluted using optimized elution protocol. The interactions between template and monomers were proposed of the basis of semiempirical PM3 theoretical calculation.

Pyrazinecarbonitriles and acetylpyrazines have widely been used as intermediates in the synthesis of various heterocyclic derivatives. Acetylpyrazines also serve as food and tobacco flavourants. In our laboratory, the title compounds have been used as synthetic intermediates for the preparation of potential antifungal and antimycobacterial drugs. Homolytic alkylation of commercially available pyrazine-2-carbonitrile yielded a series of 5-alkylpyrazine-2-carbonitriles that were then converted to the corresponding 1-(5-alkylpyrazin-2-yl)-1-ethan-1-ones (5-alkylpyrazine-2-acetylpyrazines) via the Grignard reaction. Homolytic acetylation of pyrazine-2-carbonitrile yielded 5-acetylpyrazine-2-carbonitrile. By means of the same procedure 3-acetyl-5-tert-butylpyrazine-2-carbonitrile was obtained using 5-tert-butylpyrazine-2-carbonitrile as a starting material. The hydrophobicity of all the pyrazinecarbonitriles and acetylpyrazines was determined using the reversed phase high performance liquid chromatography (RP-HPLC) method (isocratic elution with methanol as an organic modifier in the mobile phase, end-capped non-polar C18 stationary RP column). Experimentally derived Log K values (the logarithm of capacity factor K) were that compared with Log P values calculated by commercially available programmes (CS ChemOffice Ultra ver. 7.0 and ACD/Log P ver. 1.0).

The series of quinoline derivatives were prepared. The synthetic procedures of compounds are presented. All the prepared derivatives were analyzed using the reversed phase high performance liquid chromatography (RP-HPLC) method for the lipophilicity measurement. In the present study the correlation between RP-HPLC retention parameter Log K (the logarithm of capacity factor K) and various calculated Log P data is shown. 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.). Structure-activity relationships between the chemical structure and the biological activities of the evaluated compounds are discussed.