19 research outputs found
Increasing permeability of phospholipid bilayer membranes to alanine with synthetic α-aminophosphonate carriers
A series of aminophosphonates was synthesized, and their ability to carry alanine, a model hydrophilic molecule, across phospholipid bilayer membranes was evaluated. Aminophosphonates facilitate the membrane transport at moderate rates, which make them a suitable platform for the design of carriers for continuous drug release devices. © 2008 Elsevier Ltd. All rights reserved
Calix[4]arene based α-aminophosphonates: Novel carriers for Zwitterionic amino acids transport
A series of calix[4]arene based α-aminophosphonates were synthesized by the Kabachnik-Fields reaction of the calixarene-diamine (either at lower or upper rim), diethyl phosphite and a carbonyl compound (acetone or cyclohexanone). These compounds exhibited remarkable selectivity as carriers for the membrane transport of the zwitterionic form of aromatic amino acids
New calix[4]arene-based amides - Their synthesis, conformation, complexation
New chiral calix[4]arene-based diol-diamides 1a, 1b, tetraamides 2a, 2b and 7 as well as achiral diamide 3 and tetraamides 4-6 were prepared. The conformation of 1 has been studied in solution by NMR and in solid state by X-ray crystallography. The pinched-cone conformation of the calix[4]arene skeleton in 1 was found to be stabilized by a circular array of hydrogen bonds formed by two phenolic O-H and two amidic N-H bonds at lower rim. Whereas no significant complexation of Na+ was observed in solution for diamides 1 and 3, tetraamides 2, 4, 5, and 6 give strong complexes with Na+ as confirmed by NMR titrations of 2 and 4. The influence of anions and the solvents used on complexation ability of 2 towards Na+ is negligible
Synthesis of Upper and Lower Rim Binaphthyl Bridged Calix[4]arenes: New Potential Chiral Hosts for Molecular Recognition and Catalysis
New chiral upper and lower rim (R)-binaphthyl-bridged calix[4]arenes in the cone conformation (5, 10, 11, 15, 17, 18) have been synthesized by exploiting the selective functionalization of the calix[4]arene skeleton, The conformational properties of the new hosts in CDCl3 and DMSO-d(6) have been clarified by dynamic NMR measurements, and their complexation properties toward neutral molecules, alkali metal, and silver(I) cations have been explored. The upper rim binaphthyl-bridged calix[4]arene 5 is able to form a 1:1 complex with Ag+ in CDCl3:CD3OD 1:1 v/v solution, where the silver cation is encapsulated into the apolar cavity. The determined association constant (log K = 3.51) is substantially higher than for unbridged calix[4]arenes in the cone conformation. These new macrobicyclic compounds are potential hosts for chiral recognition and catalysis
Increasing permeability of phospholipid bilayer membranes to alanine with synthetic α-aminophosphonate carriers
A series of aminophosphonates was synthesized, and their ability to carry alanine, a model hydrophilic molecule, across phospholipid bilayer membranes was evaluated. Aminophosphonates facilitate the membrane transport at moderate rates, which make them a suitable platform for the design of carriers for continuous drug release devices. © 2008 Elsevier Ltd. All rights reserved
Increasing permeability of phospholipid bilayer membranes to alanine with synthetic α-aminophosphonate carriers
A series of aminophosphonates was synthesized, and their ability to carry alanine, a model hydrophilic molecule, across phospholipid bilayer membranes was evaluated. Aminophosphonates facilitate the membrane transport at moderate rates, which make them a suitable platform for the design of carriers for continuous drug release devices. © 2008 Elsevier Ltd. All rights reserved
Calix[4]arene based α-aminophosphonates: Novel carriers for Zwitterionic amino acids transport
A series of calix[4]arene based α-aminophosphonates were synthesized by the Kabachnik-Fields reaction of the calixarene-diamine (either at lower or upper rim), diethyl phosphite and a carbonyl compound (acetone or cyclohexanone). These compounds exhibited remarkable selectivity as carriers for the membrane transport of the zwitterionic form of aromatic amino acids
Calix[4]arene based α-aminophosphonates: Novel carriers for Zwitterionic amino acids transport
A series of calix[4]arene based α-aminophosphonates were synthesized by the Kabachnik-Fields reaction of the calixarene-diamine (either at lower or upper rim), diethyl phosphite and a carbonyl compound (acetone or cyclohexanone). These compounds exhibited remarkable selectivity as carriers for the membrane transport of the zwitterionic form of aromatic amino acids
Calix[4]arene based α-aminophosphonates: Novel carriers for Zwitterionic amino acids transport
A series of calix[4]arene based α-aminophosphonates were synthesized by the Kabachnik-Fields reaction of the calixarene-diamine (either at lower or upper rim), diethyl phosphite and a carbonyl compound (acetone or cyclohexanone). These compounds exhibited remarkable selectivity as carriers for the membrane transport of the zwitterionic form of aromatic amino acids