Cage-type molecules

The simplest cage-type molecule is white phosphorus. P4. Although P, molecules, isoeleclroric with N,. are found in phosphorus vapor at higher temperatures. P is more stable at room temperature. "w This molecule is a tetrahedron of phosphorus atoms ... 

In this contribution we present a review on recent developments in the field of advanced clustered and polymeric carbon materials. The carbon clusters to be discussed refer to the recently discovered cage type molecules of the fullerene family rather than to a conventional aggregation of a small number of atoms. The polymeric carbon materials are carbyne like pure carbon chains grown from teflon by an internal electrochemical reduction process. ... 

Higa T, Fukui M, Fukui K, Naganuma Y, Kajita Y, Inomata T, Ozawa T, Funahashi Y, Hideki M (2010) Simplified bicyclic cage-type molecule as a C5-symmetric host X-ray and FUR characterization of encapsulation of a nitrile molecule. J Incl Phenom Macrocycl Chem 66 171-177... 

Packing of the cyclodexthn molecules (a, P, P) within the crystal lattice of iaclusion compounds (58,59) occurs in one of two modes, described as cage and channel stmctures (Fig. 7). In channel-type inclusions, cyclodextrin molecules are stacked on top of one another like coins in a roU producing endless channels in which guest molecules are embedded (Fig. 7a). In crystal stmctures of the cage type, the cavity of one cyclodextrin molecule is blocked off on both sides by neighboring cyclodextrin molecules packed crosswise in herringbone fashion (Fig. 7b), or in a motif reminiscent of bricks in a wall (Fig. 7c). 

Facile syntheses of highly symmetric cage-type cryptands consisted of pyridine rings and their properties as host molecules 98YGK604. 

According to Steiner et al. [69], who studied the complex of /TCD with 1,4-butanediol, a monomer model of PTHF, the crystal packing in this complex is the cage type and isomorphous to that of the jS-CD hydrate, and the methylene chain vibrates in the cavity. However, in the /J-CD-PTHF complex, the polymer chain lays fixed inside a column formed by linearly bonded CD molecules. In agreement with this picture, CP/MAS NMR spectra showed the PTHF chain in the complex to be much less flexible than that in its mixture with the CD. 

The cage-type peptide cyclophanes (7 and 8) exhibit discrimination toward steroid hormones, as effected by hydrophobic and n-n interactions. In addition, the chirality-based discrimination between a- and -estradiol as well as between D- and L-amino acids bearing an aromatic moiety is performed on the basis of their capacity of forming efficient hydrogen bonding with the host molecules in aqueous media [41, 43]. 

The cage-type cyclophane furnishes a hydrophobic internal cavity for inclusion of guest molecules and exercises marked chiral discrimination in aqueous media. The host embedded in the bilayer membrane is capable of performing effective molecular recognition as an artificial cell-surface receptor to an extent comparable to that demonstarated by the host alone in aqueous media. 

The isolated molecule C28 point symmetry group is Td. The 42 covalent bonds of three different types take part in forming of the cage of molecule ... 

On the other hand, host-guest systems being composed of preorganized macrocyclic, cage-type or rigid acyclic host molecules... 

In cage-type A packing motifs, cyclodextrin molecules are arranged cross-wise in a herringbone mode. This packing is found for a-, / -, and y-cyclodextrins if... 

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