Mimics, enzyme cyclophanes

Carcerands and Hemicarcerands, p. 189 Concave Reagents, p. i /1 Crown Ethers, p. 326 Cryptophanes, p. 340 Cyclodextrins, p. 398 Cyclodextrins, Applications, p. 405 Cyclophanes Definition and Scope, p. 414 Enzyme Mimics, p. 546 Macrocycle Synthesis, p. 830 Organometallic Anion Receptors, p. 1006 Soft and Smart Materials, p. 1302 X-Ray Crystallography, p. 1586... 

Cyclophanes Endoacidic, Endobasic, and Endolipophilic Cavities, p. 424 Dendrimers. p. 432 The Diphenylmethane Moiety, p. 452 Enzyme Mimics, p. 546... 

Morales. J.C. Zurita. D. Penades. S. Carbohydrate-carbohydrate interactions in water with glycophanes as model systems. J. Org. Chern. 1998. 63. 9212-9222. Habicher. T. Diederich, F. Catalytic dendrophanes as enzyme mimics Synthesis, binding properties, micropolarity effect, and catalytic activity of dendritic thiazolio-cyclophanes. Helv. Chim. Acta 1999. 82, 1066-1094. Bartsch, R.A. Kus, P. Dailey, N.K. Kou. X. A novel cyclophane-anthracene complex. Tetrahedron Lett. 2002. 43. 5017-5019. 

Metalloporphyrins have been used for epoxidation and hydroxylation [5.53] and a phosphine-rhodium complex for isomerization and hydrogenation [5.54]. Cytochrome P-450 model systems are represented by a porphyrin-bridged cyclophane [5.55a], macrobicyclic transition metal cyclidenes [5.55b] or /3-cyclodextrin-linked porphyrin complexes [5.55c] that may bind substrates and perform oxygenation reactions on them. A cyclodextrin connected to a coenzyme B12 unit forms a potential enzyme-coenzyme mimic [5.56]. Recognition directed, specific DNA cleavage... 

Synthetic molecular receptors command widespread interest as mimics of membrane transport agents and enzyme active sites.[1,2] The development of new host systems for the selective complexation of organic and inorganic cations and anions has mushroomed in recent years however, examples of solution phase coordination of neutral organic molecules are few. Most of these examples involve inclusion of an aromatic hydrocarbon into the hydrophobic pocket of a water soluble cyclodextrin or cyclophane receptor.[3-6] A smaller subset of synthetic receptors possess lipophilic exteriors and hydrophilic cavities for the association of polar substrates in nonpolar media. [7-9] We report here the synthesis and characterization of a new system of the latter type designed to bind polar guests in chloroform solution. 

Many enzymes contain deeply buried apolar binding sites within their globular structures. We were interested in using dendritically shielded cyclophanes to mimic such behaviour and this led to the synthesis of a new class of molecules the dendrophanes dendniic cyc ophanes).[ 6] The synthesis of dendrophanes such as 2 (Fig. 2) was... 

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