Design, synthesis, and time-gated cell imaging of carbon-bridged triangulenium dyes with long fluorescence lifetime and red emission

Abstract

Introduction of an isopropyl bridge in the triangulenium skeleton leads to a new series of redshifted triangulenium dyes with high fluorescence quantum yields and remarkable long fluorescence lifetime allowing for time-gated cell imaging.

C‐Functionalized Cationic Diazaoxatriangulenes: Late‐Stage Synthesis and Tuning of Physicochemical Properties

“…1700-1900 cm 1 ). Their diminished intensity and lifetimes, together with the absence of signal for amino derivative 4,i sc onsistentw ith previouso bservations on cationic diaza [4]-and [6]helicenes introducing strong donor groups. [15b,d] Finally,i ti sn oteworthy to underline that deprotonation of carboxylic derivative 8-H + to zwitterionic form 8 leads to 46 and 72 nm (1430a nd 1880 cm À1 )r edshifts of absorptiona nd fluorescencem axima, respectively.S uch as ystem may find particular interest as ap H-sensitive probe for biological applications.…”

“…[5] These derivatives (Figure 1), which differ by the number of bridging oxygen and nitrogen atoms, are commonly named TOTA, ADOTA, DAOTA, and TATA in view of their trioxa,a zadioxa, diazaoxa, andt riaza nature,respectively. [6] They present 1) exceptionally high chemical stabilities forc arbenium ions (pK R + up to 23.7), [7] and 2) intense fluorescence in thev isible range characterized by particularly long lifetimes. [8] Syntheses are straightforwardf rom simple triarylcarbenium precursors (one to three steps in total).…”

“…This sequenceo fr e- actions is, to the best of our knowledge,t he only example of regioselective late-stage functionalization of at riangulene skeleton. [14] Herein, inspired by studies on the postfunctionalization of related cationic [6]-and [4]helicenes, [15] we report on the regioselectiven itration andf ormylation of DAOTA 1 that has openedu pu nprecedented access to various triangulenes functionalized at position6( compounds 2-10). The C-substituents influence the solid-state conformations and packingo ft he structures.…”

Spectral shifts of BODIPY derivatives: a simple continuous model

“…In part A of the figure, the familiar behavior, known from color struc-ture relationship theory, for an odd numbered linear chain of π-orbitals is shown. 38,39 Substitutions on the unstarred sites (3,5 or 1,7 or 8) show similar behavior. EDGs induce blueshifts and EWGs induce red-shifts.…”

Time-gated fluorescence imaging: Advances in technology and biological applications

“…Recovery of the concealed micro objects such as large molecules, 11,28 cells, 11,23,29,34,36,39,41,47,49,66,70,72,[74][75][76][77][78][79][80][81][82][83][84] and microorganisms 24,30,32,71,85 from annoying interference (e.g., background AF) in°uorescence imaging with the help of TG technique has attracted increasing attention for years. Marriott et al presented a simple TG microscope and utilized it to visualize the delayed luminescence intensities and lifetime of acridine dyes on polytene chromosomes.…”