engleski

Determination of ethyl-phenyl macrozone reaction mixture components by LC-SPE/NMR methodology

Azithromycin is the most widely used broad- spectrum antibiotic due to it's exceptional therapeutic properties.[1] Despite to this fact, an increasing number of antibiotic- resistant bacteria demands more effective antimicrobial agents to be synthesized.[2] Third generation of macrolide antibiotics still lacks activity against some Gram-negative bacterial strains, especially against respiratory tract pathogens. In order to improve antibacterial activity, new synthetic approaches were described in the literature.[3] Conjugation of the azithromycin analogue, 9a- (γ-aminopropyl) derivative, and thiosemicarbazide moieties resulted in novel compounds, macrozones, which showed good in vitro activity against selected Gram positive and Gram negative bacterial strains. Preparative and semi-preparative liquid chromatography are classical methods for purification and isolation of the final product, but they are time and solvent consuming. Modern hyphenated NMR techniques, such as LC-SPE/cryoNMR, are much faster, more efficient and more sensitive tool for the isolation and identification of the reaction mixture components. [4, 5] In this study LC- SPE/cryoNMR technique was used for the isolation of a novel ethyl-phenyl macrozone and for impurity profiling of the reaction mixture.

macrozones ; azithromycin ; thiosemicarbazides ; LC-SPE-NMR

nije evidentirano