the conformational behavior of monosubstituted tri-methylsilyle ethynyl derivative of cal ix[4]arene as a newgeneration of caliarene was compared with tetra alkylated calyx[4]arene. the most important conformationalphenomena in these compounds which are pinched cone interconversion process were done by semi-empiricalmethod and ab initio calculations with gaussian 98w programming.

The conformational behavior of monosubstituted tri-methylsilyle ethynyl Derivative of Cal ix[4]arene as a newgeneration of Caliarene was compared with tetra alkylated calyx[4]arene. The most important conformationalphenomena in these compounds which are pinched cone interconversion process were done by semi-empiricalmethod and ab initio calculations with Gaussian 98w programming.

Cone-shaped calix[4]arene-tetrol 3 has the ability to form open structures due presence of four OH groups at upper rim, which allows construction H-bonded supramolecular organic frameworks (SOFs). In water, SOF-1 is formed, contains hydrophilic channels (mean diameter 8.5 Å) contoured by p-phenolic groups. acetonitrile, SOF-2 smaller hydrophobic 6.6 delimited aromatic walls. The Na+@3 complex, ...

The title compound, C42H48O6, was obtained via formyl-ation of 25,26,27,28-tetra-propoxycalix[4]arene with dichloro-methyl methyl ether and tin tetra-chloride. It adopts a pinched cone conformation, which leads to an open cavity. The two opposite aromatic rings bearing formyl groups are almost parallel, making a dihedral angle of 29.1 (2)°. The other pair of opposite rings are close to being pe...

‎‎in cite{fr 1‎, ‎fr 2} using faithful complex representations of cyclically pinched and conjugacy pinched one-relator groups we proved that any limit group has a faithful representation in $psl(2,c)$‎. ‎further this representation can be effectively constructed using the jsj decomposition‎. ‎in this note we show that any hyperbolic cyclically pinched one-relator group with maximal amalgamated ...

The title thia-calix[4]arene derivative, C(36)H(34)Br(2)O(8)S(4), adopts an unusual pinched cone conformation with the prop-oxy-substituted benzene rings inclined inward [forming a dihedral angle of 33.4 (1)°] and with the brominated benzene rings bent outward, making a dihedral angle of 66.1 (1)°. In the crystal, the mol-ecules form chains along [001] via C-H⋯S hydrogen bonds and S⋯S contacts ...

Alkoxy side-chain-flanked diarylsulfonamide serves as a reliable structural motif for constructing macrocyclic aromatic tetrasulfonamides. This 90 degrees structural motif is persistent both in solution and in the solid state, which allows the one-step formation of tetrasulfonamide macrocycles. These macrocycles adopt a cone-shaped conformation in solution and in the solid state. For each molec...

Reaction of [enM(H2O)2](NO3)2 (en = ethylenediamine, M = PdII, PtII) with 2-hydroxypyrimidine (Hpymo) in water results in self-assembly to cyclic complexes of type [enM(pymo-N1,N3)]4(NO3)4 (1, M = PdII; 2, M = PtII) which are structurally analogous to calix[4]arenes. The tetranuclear cations in compounds 1 and 2 adopt, in the solid state, a 1,3-alternate orientation of the pymo residues. Attemp...

This paper concerns pinched surfaces, also known as pseudosurfaces. A map is a graph G embedded on an oriented pinched surface. An arc of a map is an edge of G with a fixed direction. A regular map is one with a group of orientation-preserving automorphisms that acts regularly on the arcs of a map, i.e., that acts both freely and transitively. We study regular maps on pinched surfaces. We give ...