Spectrophotometry, drug structure

After s)mthesis it is important to determine the drug s exact chemical structure. This will involve a variety of techniques such as mass spectrometry, nuclear magnetic resonance (H and C ), infrared and ultraviolet/visible spectrophotometry along with elemental analysis. This will confirm the medicinal chemist s proposed... 

The emphases of this section reflect the author s own special interests in using CD detection to directly determine chiral substrates. The majority of the systems described are drug substances. Direct analytical applications over the last 20 or so years have clearly demonstrated that a priori expectations of serious interference problems are ill-founded. Analytical sensitivities similar to those for absorbance spectrophotometry are readily accessible, and a high degree of analytical selectivity is obtained because of that very same property that makes ORD and CD such useful structural tools, namely, the sensitivity of a chromophore to its chiral environment. Substrates are organized into three groups ... 

Besides, the actual distance existing between two vital functional moieties may be almost fixed arbitrarily in rigid molecular structural variants. These restructured and strategically positioned newer targetted-drug molecules may be subjected to vigorous and critical examinations by the aid of several sophisticated latest physicochemical analytical devices, such as X-Ray diffraction analysis Optical Rotary Dispersion (ORD) NMR-spectroscopy Mass Spectroscopy FTIR-Spectrophotometry and the like. 

If the objective is identification (qualitative analysis), it suffices to compare the spectrum of the analyte with that of a standard, both recorded in the same solvent and at an identical pH. This is not the main application of UV-Vis spectrophotometry as the best results in this context are provided by spectroscopic methods considered more effective for the study of the molecular structure of organic compounds (infrared, nuclear magnetic resonance, mass spectrometry, and X-ray diffraction). However, UV-Vis spectrophotometry is a source of relevant supplementary information that helps in the elucidation of molecular structures of drugs, impurities, metabolites, intermediate compounds of degradation, etc. 

Kumar S, Pandya P, Pandav K, Gupta SP, Chopra AN (2012) Structural studies on ligand DNA systems a robust approach in drug design. J Biosci 37(3) 553 561 Kruglova EB, Gladkovskaya NA, Maleev VY (2005) The use of the spectrophotometry analysis for the calculation of the thermodynamic parameters in actinocin derivative-DNA systems. Biophysics 50(2) 253-264... 

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