Molecular design absorption

Molecular designers can exploit these rules and design chemicals that demonstrate characteristics that are likely to lead to decreased absorption and therefore minimize toxicity. Molecules that are permanently charged at physiological pH like the neurotoxin curare or... 

Another approach to shift absorption bands for the colored form is the extension of Jt-conjugation outside the spiro skeleton. Procedures of molecular designs for such photochromic compounds are shown in Scheme 20. (1) Position for extension of additional -conjugation in spirothiopyran... 

With the help of similar molecular design, spirothiopyranonaphtho-pyrans 19 with absorption band in the near IR (692-850nm) on UV irradiation have been prepared.52 As predicted, the photocoloration of these spirothiopyrans occurs, but the reverse reaction to colorless form does not occur in solution as extension of Jt-conjugation increases. 

Verma, R.P., Hansch, C. and Selassie, C.D. (2007) Comparative QSAR studies on PAMPA/modified PAMPA for high throughput profiling of drug absorption potential with respect to Caco-2 cells and human intestinal absorption. Journal of Computer-Aided Molecular Design, 21, 3-22. 

Photochromism is defined as the reversible photo-induced transformation of a substance into its two isomers that differ in absorption spectra and other physicochemical parameters [1-4]. Over the past decade, the molecular design and synthesis... 

Li, Y., 2012. Molecular design of photovoltaic materials for polymer solar cells toward suitable electronic energy levels and broad absorption. Acc. Chem. Res. 45, 723-733. 

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