Calixarenes definition

However, the yield value has to be carefully considered. In fact, though calixarenes present the lowest degradation G values, a loss of 50% of the molecule was observed under an irradiation dose of 1 MGy (72), which is comparable to the degradation rate of malonamides (loss of 40% under irradiation dose of 0.75 MGy) (48). This difference can be explained by the definition of the yield, which took into account the number of molecules, and therefore favored processes in which the concentration of the extractant was low (e.g., calixarene 10-2 mol L-1). 

The most definitive conformational representation of a calixarene is derived from X-ray crystallography, although even these pictures sometimes fail to... 

Calixarenes developed by Gutsche belong to a family of cyclophanes by definition, and much attention has focused on their catalytic functions as artificial enzymes based on their versatile molecular recognition... 

No conclusion can adequately summarize the developments in the topic of this article. Host-guest chemistry is still in its infancy as a typical multidisciplinary subject. The progress in all basic disciplines will immediately provoke progress in the level of our knowledge on molecular complex formation by calixarenes. The synthesis of many new ligands and their thorough study will definitely be required to better understand the multifaceted problem of molecular recognition and complex formation. 

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