Synthesis and Molecular Recognition of Pyrenophanes with Polycationic or Amphiphilic Functionalities:  Artificial Plate-Shaped Cavitant Incorporating Arenes and Nucleotides in Water

Abstract

Water-soluble pyrenophanes possessing polycationic or amphiphilic side chains have been developed as synthetic host molecules to investigate hydrophobic and/or pi-stacking interactions. By utilizing omega-acetalic alkyl side chains to retain solubility and versatility, water-soluble macrocyclic pyrenophanes could be easily obtained by Stille coupling, followed by conversion of the acetal groups to hydrophilic substituents. Among the pyrenophanes synthesized, hexaammonium-, bis(diazoniacrown)-, and tetrakis[octa(oxyethylene)]-derived ones showed enough solubility in pure water. The former two cationic pyrenophanes strongly recognized anionic arenes including nucleotides, while the latter neutral one associated with monopyrenyl guests regardless of their electric natures. The strength of recognition for nucleotides by bis(diazoniacrown)pyrenophane depended on the number of phosphate moieties, decreasing in the following order: triphosphate >> diphosphate approximately monophosphate.

Alkynylpyrenes as Improved Pyrene‐Based Biomolecular Probes with the Advantages of High Fluorescence Quantum Yields and Long Absorption/Emission Wavelengths

“…Bromination of pyrene (1) with one to four equivalents of bromine gave the mono-, di-, tri-, and tetrabromopyrenes, respectively (1-bromopyrene (14), 1,6-dibromopyrene (15), 1,3,6-tribromopyrene (16), and 1, 3,6,8-tetrabromopyrene (17)). [23] Cross-coupling of these bromopyrenes with (trimethylsilyl)acetylene under the conditions of the Sonogashira reaction afforded mono-, bis-, tris-, and tetrakis(trimethylsilylethynyl)pyrenes 2-5, respectively.…”

“…Unsymmetrical dialkynylpyrene 10, designed as a water-soluble alkynylpyrene, was prepared in a stepwise manner via monosubstituted 20 starting from 1,6-diiodopyrene (18) and the hydrophilic acetylene 19. Alkynylpyrenes 11-13 for biomolecular probes were each prepared from 1-bromopyrene (14). Sonogashira reactions of 14 with 4-ethynylaniline and 3-(4-ethynylphenyl)propionic acid (23) gave intermediates 21 and 24, respectively.…”

Binding Mechanisms in Supramolecular Complexes

“…Example of a change in the binding mechanism as a result of changing the pH value. The constants rise to as much as 1 10 6 [214] with the sevenfold charged heptaamino-bcyclodextrin. The difference DDG = DG XP ÀDG X is a constant (10 AE 2) kJ mol À1 , which is consistent with the presence in each case of two salt bridges between a host ammonium center and a guest phosphate ion.…”

The optical properties and quantum chemical calculations of thienyl and furyl derivatives of pyrene

“…The pyrene structure is well studied and has been intensively examined in the fields of biology, chemistry and physics. Moreover, due to its electro conductive properties, pyrene and its derivatives have been successfully applied as micro environmental sensors [33][34][35][36] , liquid crystals 37,38 , and photoactive polypeptides 39 . Pyrene is a flat aromatic molecule and exhibits excellent fluorescent properties.…”