Per-6-amino-p-cyclodextrin

The formation of hydrophilic molecular capsules by self-assembly of two cyclodextrin entities in the presence of a guest has been investigated. A system of this type was demonstrated to self-assemble from per-6-amino P-cyclodextrin (34) and per-6-thioglycolic P-cyclodextrin (35) in 50 mmol dm KCl solution at neutral pH. The structure of the resulting dimer has been investigated using a... 

In 2010, Pitchumani and Kanagaraj reported the solvent-free multicomponent synthesis of pyranopyrazoles. The reaction of hydrazine, ethyl acetoacetate, malononitrile, and aromatic aldehydes catalyzed by per-6-amino-p-cyclodextrin at room temperature afforded the corresponding pyranopyrazoles in quantitative yields [56]. 

K. Kanagaraj, K. Pitchumani, Tetrahedron Lett. 2010, 51, 3312-3316. Solvent-free multicomponent synthesis of pyrano-pyrazoles per-6-amino-p-cyclodextrin as a remarkable catalyst and host. 

Catalyst Per-6-amino-p-cyclodextrin (per-6-ABCD) — acts as a supramolecular host and a reusable solid base catalyst... 

Pitchumani and coworkers have found that per-6-amino-P-cyclodextrin (per-6-ABCD) catalyzes efficiently the Henry reaction in aqueous media [12], Thus, a series of aldehydes react with nitromethane or nitroethane to afford the corresponding P-nitroalcohol derivatives in excellent yields (88-99%) and selectivities (dr > 15 1 and 79-99% ee) when using aromatic aldehydes, whereas aliphatic aldehydes afforded variable results (72-88% yield, 52-79% ee). 

Organocatalysis Continuing efforts to harness the cooperative activity of bifunctional organocatalysts have led to the examinations of chiral calix[4]arenes containing amino phenol stractures and chiral per-6-amino-P-cyclodextrin in the asymmetric sulfa-Michael reactions to cyclic and acylic enones.The preliminary results indicated that further structural modification would be required to allow more efficient asymmetric catalyst systems. 

Suresh P, Pitchumani K. Per-6-amino-p-cyclodextrin catalyzed asymmetric Michael addition of nitromethane and thiols to chalcones in water. Tetrahedron Asymm. 2008 19 2037-2044. 

Cyclodextrins which are cyclic oligosaccharides built up of six, seven or eight 1-4-linked glucopyranose units (a-CD, P-CD and y-CD, respectively) may be modified by lipophilic substitution on one of their two hydrophilic faces surrounding a hydrophobic cavity to form amphiphilic molecules. A schematic model of a modified p-CD with 7 grafted C12 chains at the primary face and with 14 hydroxilic groups at the secondary face is illustrated in Fig. 2. The synthesis route of such a molecule starting from per-(6-amino-6-deoxy) -cyclodextrin is depicted in Fig. 3. 

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