Structure-activity relationship


Structure-activity relationship

Structure-activity relationships (SAR) are the traditional practices of medicinal chemistry which try to modify the effect or the potency (i.e. activity) of bioactive chemical compounds by modifying their chemical structure. Medical chemists use the chemical techniques of synthesis to insert new chemical groups into the biomedical compound and test the modifications in their biological effect.

This enables the identification and determination of the chemical groups responsible for evoking a target biological effect in the organism. This method was later refined to build mathematical relationships between a chemical structure and its biological activity, known as (Q)SAR.

Related is the term SAFIR: structure affinity relationship.

AR and SAR paradox

The basic assumption for all molecule based hypotheses is that similar molecules have similar activities. This principle is also called Structure-Activity Relationship (SAR). The underlying problem is therefore how to define a "small" difference on a molecular level, since each kind of activity, e.g. reaction ability, biotransformation ability, solubility, target activity, and so on, might depend on another difference. A good example was given in the bioisosterism review of Patanie/LaVoie. [G. A. Patani, E. J. LaVoie, "Bioisosterism: A Rational Approach in Drug Design". Chem. Rev., 1996, 96, 3147-3176. doi|10.1021/cr950066q]

In general, one is more interested in finding strong trends. Created hypotheses usually rely on a finite number of chemical data. Thus, the induction principle should be respected to avoid overfitted hypotheses and deriving overfitted and useless interpretations on structural/molecular data.

The SAR paradox refers to the fact that it is not the case that all similar molecules have similar activities.

References

External links

* http://www.qsarworld.com


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Quantitative structure-activity relationship — (QSAR) is the process by which chemical structure is quantitatively correlated with a well defined process, such as biological activity or chemical reactivity.For example, biological activity can be expressed quantitatively as in the… …   Wikipedia

  • Quantitative structure-activity relationship — Relation quantitative structure à activité Une relation quantitative structure à activité (en anglais : Quantitative structure activity relationship ou encore QSAR) est le procédé par lequel une structure chimique est corrélée avec un effet… …   Wikipédia en Français

  • quantitative structure-activity relationship — Abbreviation: QSAR A computer modelling technique that enables the prediction of the likely activity of a molecule before it is synthesized. QSAR analysis relies on recognizing associations of molecular structures and activity from historical… …   Glossary of Biotechnology

  • structure-activity analysis — (= structure activity relationship; SAR) Study in which systematic variation in the structure of a compound is correlated with its activity, in an attempt to determine the characteristics of the (receptor) site at which it acts …   Dictionary of molecular biology

  • Conformation activity relationship — is the relationship between the biological activity and the conformation or conformational changes of a biomolecule. This terminology emphasizes the importance of dynamic conformational changes for the biological function, rather than the… …   Wikipedia

  • Relationship between religion and science — Part of a series on Science …   Wikipedia

  • Structure and agency — The debate surrounding the influence of structure and agency on human thought and behaviour is one of the central issues in sociology and other social sciences. In this context agency refers to the capacity of individual humans to act… …   Wikipedia

  • Structure-Organization-Process — In The Tree of Knowledge (1997:47), Humberto Maturana and Francisco Varela set out a way of describing the nature of living things: “… [An] organization denotes those relations that must exist among components of a system for it to be a member of …   Wikipedia

  • Relation quantitative structure à activité — Une relation quantitative structure à activité (en anglais : Quantitative structure activity relationship ou QSAR, parfois désignée sous le nom de relation quantitative structure à propriété en anglais : quantitative structure property… …   Wikipédia en Français

  • Relation quantitative structure a activite — Relation quantitative structure à activité Une relation quantitative structure à activité (en anglais : Quantitative structure activity relationship ou encore QSAR) est le procédé par lequel une structure chimique est corrélée avec un effet… …   Wikipédia en Français


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.