کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1222484 | 1494672 | 2012 | 5 صفحه PDF | دانلود رایگان |
Streptomycin, the classical aminoglycoside antibiotic, generally considered the most basic drug compound was characterized in terms of protonation macro- and microconstants.1H NMR–pH and 1H–13C HSQC–pH titrations were carried out on streptomycin and streptidine, a symmetrical constituent compound of reduced complexity to monitor the proton-binding processes of the basic sites. Accurate, undistorted, electrodeless pH measurement was ensured by a new set of in tube indicators.The microscopic protonation constants of the two guanidino groups of streptomycin were calculated by evaluating the various NMR–pH data and transferring the pair-interactivity parameter from streptidine to streptomycin. Inherent guanidino basicities fall in the range of 13.03–13.39 log k units, which drop to 12.48–12.85 upon protonation of the other site. pH-dependent distribution of the major microspecies and charge-related biological consequences are provided.
► Accurate, unbiased protonation constants of streptomycin and streptidine.
► Pair interactivity parameter between two guanidino groups.
► Microconstants of the guanidino groups in streptomycin.
► Error analysis of the microconstants.
Journal: Journal of Pharmaceutical and Biomedical Analysis - Volume 59, 5 February 2012, Pages 78–82