A tryptophan-containing fluorescent intramolecular complex as a designer peptidic proton sensor

Abstract

Pyrene and tryptophan groups judiciously placed on a novel molecular scaffold, namely, bispidine exhibited fluorescence due to the formation of an unprecedented emissive intramolecular complex in polar solvents. Upon protonation, the emission signal from the pyrene unit enhances at the expense of the emission signal from the complex. The probe demonstrates good sensitivity, excellent selectivity, and adequate reversibility towards proton sensing. The present design based on the bispidine scaffold opens up newer opportunities for the design of novel bispidine-peptide sensors.

Fluorescence Quenching of Dipyrenylalkanes by an Electron/Charge Acceptor

“…Molecular scaffolds that are appended by a judiciously selected fluorescence probe at multiple locations have been investigated intensely in the last few decades. − Several of these multifluorophore-appended molecular systems exhibit a bathochromically shifted structureless broad emission band in addition to the usual emission features from the monomeric fluorophore. − The bathochromic band, in general, is characteristic of the fluorescence from the excimer. An intramolecular excimer is a dimer that is thus formed unimolecularly only in the excited-state within such molecular systems. − These intramolecular excimers have shown immense applications in chemistry, chemical physics, and chemical biology. − …”

Novel Pentadecyl Phenol‐Tagged L‐Tryptophan Molecules: Synthesis, Self‐ Assembly and Liquid Crystalline Properties

“…These interactions allow the steady growth of supramolecular architectures. Among all the amino acids, the fluorescent properties of tryptophan (trp, W) is well studied ,,,,. Trp acts as a biological precursor for a number of biological molecules such as serotonin and niacin.…”

“…Ditryptophan‐pyridine conjugates could act as fluorescent probes for selective binding of Hg ions . Amphiphilic ditryptophan conjugates were used for synthesizing gold nanoparticles and tryptophan based peptidic proton sensors and drug delivery vehicles containing tryptophan were also developed and studied ,…”

Revealing Signs and Hidden 1H NMR Coupling Constants in Three-Spin Systems Using Long-Lived Coherences

“…The Journal of Physical Chemistry Letters chemistry 33,34. Its 1 H NMR spectrum reveals only two coupling constants, with the third being unobservable due to its large line width, 4.05 Hz.…”

“…Bispidinone adopts a chair–chair conformation with distinct axial and equatorial protons. This compound is used in peptide design and supramolecular chemistry. , Its 1 H NMR spectrum reveals only two coupling constants, with the third being unobservable due to its large line width, 4.05 Hz. The frequencies obtained from the LLC spectrum of bispidinone are ν 1 = 9.41 Hz, ν 2 = 15.32 Hz, and ν 3 = 5.91 Hz.…”