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New carboxylate complexes of the tetraazamacrocyclic ligand N,N',N'',N'''-tetrakis(2-pyridilmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc) with Ni(II) and Zn(II) as central ions were prepared. In mixed-ligand complexes (endo,endo)-bicyclo2.2.1hept-5-ene-2,3-dicarboxylate dianion (C9H8O4 2-) is also coordinated to metal ions. The complexes were characterized by elemental analysis (C, H, N), FTIR and UV–Vis spectroscopy, molar conductivity determination and magnetic susceptibility measurement at room temperature. The analytical data of the complexes show the formation of binuclear [Ni2(C9H8O4)tpmc](ClO4)2·4H2O and tetranuclear [Zn4(C9H8O4)(tpmc)2](ClO4)6· ·CH3CN·KClO4·4H2O complexes. In tetranuclear Zn(II) complex bicyclic dicarboxylate ligand is most likely to be bridge coordinated, and in binuclear Ni(II) complex it is coordinated in a combined bridged manner with chelate rings formation. In both complexes macrocyclic ligand was exo coordinated, out of cyclam ring and adopts a boat conformation. The Zn(II) complex is one of the rare tetranuclear Zn(II)-tpmc complexes with carboxylate ion bridging two Zn2tpmc units. The complexes were tested for antibacterial activity against Gram-positive bacteria Staphylococcus aureus (ATCC 25923) and Bacillus subtilis (ATCC 6633), Gram-negative bacterium Escherichia coli (ATCC 25922), and yeast Candida albicans (ATCC 10231), and were screened for antiproliferative activity against human cervix adenocarcinoma (HeLa) and human myelogenous leukemia (K562) cell lines. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172014 and Grant no. 175011]

A novel and efficient synthetic route has been developed for the preparation of protoberberine derivatives. The methodology designed to control, primarily, substitution patterns on the terminal rings, was used to access a small array of these compounds. Initial biological profiling suggested anticancer potential of synthesised derivatives while structure-based target fishing has identified their potential targets and has established rational basis for further structural modifications. Although the activities need further improvement, our study demonstrated that the described approach may be useful in the discovery of the novel lead compounds. [Projekat Ministarstva nauke Republike Srbije, br. 172009 i br. 175011]

The present paper describes the chemical composition and antimicrobial activity of the essential oil of the endemic species Satureja horvatii Šilić, collected in Montenegro. The essential oil was obtained from the aerial parts of the plant by hydrodistillation and analyzed by GC-MS. From the 34 compounds representing 100 % of the oil, the major compound was the phenolic monoterpene thymol (63.37 %). The oil contained smaller amounts of g-terpinene (7.49 %), carvacrol methyl ether (4.92 %), carvacrol (4.67 %), p-cymene (4.52%), a-terpinene (1.81 %), borneol (1.58 %), a-thujene (1.56 %), b-caryophyllene (1.55 %) and b-myrcene (1.44 %). The antimicrobial activity of the essential oil of S. horvatii was evaluated using the agar diffusion and broth microdilution methods. The essential oil exhibited antimicrobial activity to varying degrees against all the tested strains. The maximum activity of S. horvatii oil was observed against Gram-positive bacteria (Micrococcus luteus, Staphylococcus epidermidis, Staphylococcus aureus and Enterococcus faecalis) and against the yeast (Candida albicans). The oil exhibited moderate activity against the Gram-negative bacteria Escherichia coli and Klebsiella pneumoniae and weak activity against Pseudomonas aeruginosa. This study confirms that the essential oil of S. horvatii possesses antimicrobial activities in vitro against medically important pathogens.