Title
Comparative study of the effects of ortho-, meta- and para-carboranes (C2B10H12) on the physicochemical properties, cytotoxicity and antiviral activity of uridine and 2′-deoxyuridine boron cluster conjugates
Author
Dijana Saftić, Mirosława Studzińska, Edyta Paradowska, Ivo Piantanida, Goran Baranović, Magdalena Białek-Pietras, Zbigniew J. Leśnikowski
Year
2020
Journal
Bioorganic Chemistry
Abstract
In this study, a series of uridine (U) and 2′-deoxyuridine (dU) conjugates containing an isomeric ortho-, meta- or para-carborane cluster (C2B10H12) attached at C-5 through an ethynyl linker were synthesized. The effect of carborane cluster isomerism on the conjugate syn/anti conformation, molar extinction coefficient, lipophilicity, susceptibility to phosphorylation (by TK1, TK2 and dCK), cytotoxicity and antiviral activity was evaluated. A strong effect of the boron cluster modification on the syn/anti equilibrium of the modified nucleosides was observed. An increase in lipophilicity compared with unmodified U and dU, especially for conjugates bearing a para-carborane cluster, was detected. Furthermore a pronounced and differential influence of the boron cluster modification on the electronic properties of the nucleobase chromophore was observed. The obtained conjugates have low or medium toxicity toward several cell lines, are phosphorylated fairly well by TK1 and are poor or not substrates for dCK. Furthermore, the conjugates preferentially inhibit HCMV replication with an SI index as high as 22 for the ortho-carborane derivative of U and more than 180 for the para-carborane derivative of dU.
Instrument
V-750, J-805
Keywords
Absorption, Quantitation, Organic chemistry, Circular dichroism, Stereochemistry