Conformational restriction hydrophobic collapse

Boge, T. C. Wu, Z.-J. Himes, R. H. Vander, Velde, D. G. Georg, G. I. Conformationally restricted paclitaxel analogues macrocyclic mimics of the hydrophobic collapse conformation. Bioorg. Med. Chem. Lett., 1999, 9 3047-3052. 

STEREOCHEMICAL ASPECTS OF DRUG ACTION I CONFORMATIONAL RESTRICTION, STERIC HINDRANCE AND HYDROPHOBIC COLLAPSE... 

Boge TC, Wu Z-J, Himes RH, Vander Velde DG, Georg GI (1999) Conformationally Restricted Paclitaxel Analogues Macrocyclic Mimics of the Hydrophobic Collapse Conformation. Bioorg Med Chem Lett 9 3047... 

Alkyl or aryl moieties may form intramolecular hydrophobic interactions if this result is compatible with their relative position and the compound s flexibility. As a rule, such internal hydrophobic interactions are characteristic of folded conformers and render the solute less lipophilic than would be predicted if the hydrophobic moieties had been only partly masked from the solvent. The extreme case of hydrophobic interactions and folding is hydrophobic collapse. Hydrophobic collapse, as generally understood, should be restricted to solutes of comparatively large molecular weight (several hundred or more) and containing a number of hydrophobic moieties able to come close together to create a hydrophobic core, as, for example, in the case of some proteins and synthetic peptides. 

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