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Ivan Kos, Milena Jadrijević-Mladar, Ivan Butula, Mladen Biruš, Gordana Maravić-Vlahoviček and Sanja Dabelić

5

Synthesis and biological evaluation of a series (N = 16) of cyclic and acyclic hydroxyurea derivatives, including benzotriazole-, isocyanuric acid- and biuret-containing compounds, are disclosed. 1-N-(benzyloxycarbamoyl)benzotriazole was used as a benzyloxyisocyanate donor, a useful intermediate in the preparation of substituted hydroxyurea. Antibacterial activities of synthesized hydroxyurea derivatives were tested on three E. coli strains, i.e., a strain susceptible to antibiotics, a strain resistant to macrolide antibiotics and a strain resistant to aminoglycoside antibiotics. Six compounds (three acyclic and three cyclic hydroxyureas) showed growth inhibition of the tested E. coli strains, with different specificity toward each strain. Results of the cytotoxic activity evaluation revealed that twelve out of sixteen test compounds were cytotoxic to human acute monocytic leukemia THP-1 and/or human acute T cell leukemia Jurkat cell line. 1-(N-hydroxycarbamoyl) benzotriazole () increased the metabolic activity of both cell lines. Two compounds, 1-(N-hydroxycarbamoyl) benzotriazole (5) and N,N’,N’’-trihydroxybiuret (15), were identified as potential NO donors.

Open access

Ivan Kos, Tin Weitner, Sandra Flinčec Grgac and Jasna Jablan

Abstract

Thermal properties of N-carbamoyl benzotriazole derivatives and N,N’,N’’-tribenzyloxyisocyanuric acid were investigated using thermogravimetric analysis and differential scanning calorimetry. The results revealed a difference between structural analogs of N-carbamoyl benzotriazole derivatives. They seem to be in agreement with the previously proposed formation of N,N’,N’’-tribenzyloxyisocyanuric acid from 1-(N-benzyloxycarbamoyl) benzotriazole, via an intermediary N-benzyloxyisocyanate acid, during heating. Substantially different thermal properties were observed for structural analogues, 1-(N-methoxycarbamoyl) benzotriazole and 1-(N-ethoxycarbamoyl) benzotriazole. In contrast to N-benzyloxyisocyanate, no corresponding reactions were observed for their decomposition products, i.e., methoxyisocyanate and ethoxyisocyanate.

Open access

Zorana Slanovic-Kuzmanović, Ivan Kos and Ana-Marija Domijan

Abstract

Metabolic syndrome (MetS) is a chronic, multi-component disease characterised by central obesity, hyperglycaemia, dyslipidaemia, and hypertension. Since MetS leads to type 2 diabetes, cardiovascular disease, development of certain cancers, and eventually to premature death, it is not surprising that it draws the attention of scientists around the world. The aetiopathology of MetS is complex and still not fully understood. This review focuses on the role of endocrine factors such as cortisol and insulin in the development of MetS. It also takes a look at some of the contributing lifestyle and genetic factors as well as at the current knowledge about its treatment.