Photoswitchable Ion Receptors

Lutolli, Alketa; Flood, Amar H.

doi:10.1002/9783527827626.ch24

Cited by 2 publications

(1 citation statement)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Shape-dynamic foldamers − are an intriguing class of receptors capable of guest binding − and molecular switching. − ,− The combinations of these two capabilities in helical photofoldamers − , has led to switchable guest binding affinities. This same behavior has also been explored using other receptor frameworks, ,,− where the photoswitch toggles receptors between high- and low-affinity states. Collectively, we are still learning the factors that control the resulting swings in guest affinity.…”

Section: Introductionmentioning

confidence: 99%

Cooperativity in Photofoldamer Chloride Double Helices Turned On with Sequences and Solvents, Around with Guests, and Off with Light

et al. 2023

Self Cite

View full text Add to dashboard Cite

Photofoldamers are sequence-defined receptors capable of switching guest binding on and off. When two foldamer strands wrap around the guest into 2:1 double helical complexes, cooperativity emerges, and with it comes the possibility to switch cooperativity with light and other stimuli. We use lessons from nonswitchable sequence isomers of aryl-triazole foldamers to guide how to vary the sequence location of azobenzenes from the end (F END ) to the interior (F IN ) and report their impact on the cooperative formation of 2:1 complexes with Cl − . This sequence change produces a 125-fold increase from anti-cooperative (α = 0.008) for F END to non-cooperative with F IN (α = 1.0). Density functional theory (DFT) studies show greater H-bonding and a more relaxed double helix for F IN . The solvent and guest complement the synthetic designs. Use of acetonitrile to enhance solvophobicity further enhances cooperativity in F IN (α = 126) but lowers the difference in cooperativity between sequences. Surprisingly, the impact of the sequence on cooperativity is inverted when the guest size is increased from Cl − (3.4 Å) to BF 4 − (4.1 Å). While photoconversion of interior azobenzenes was poor, the cis−cis isomer forms 1:1 complexes around chloride consistent with switching cooperativity. The effect of the guest, solvent, and light on the double-helix cooperativity depends on the sequence.

show abstract

Section: Introductionmentioning

confidence: 99%

Cooperativity in Photofoldamer Chloride Double Helices Turned On with Sequences and Solvents, Around with Guests, and Off with Light

et al. 2023

Self Cite

View full text Add to dashboard Cite

show abstract

Heterocyclic Hemipiperazines: Multistimuli‐Responsive Switches and Sensors for Zinc or Cadmium Ions

Schäfer,

Pianowski

2024

Chemistry A European J

View full text Add to dashboard Cite

Advance in the design of molecular photoswitches ‐ adapters that convert light into changes at molecular level – opens up exciting possibilities in preparing smart polymers, drugs photoactivated inside humans, or light‐fueled nanomachines that might in the future operate in our bloodstream. Hemipiperazines are recently reported biocompatible molecular photoswitches based on cyclic dipeptides. Here we report a multistimuli‐responsive hemipiperazine‐based switch that reacts on light, solvents, acidity, or metal ions. Its photoequilibration is controlled by the intramolecular hydrogen bonding pattern. The compound can be used as a mid‐nanomolar photoswitchable fluorescent sensor for zinc and cadmium ions, applicable to monitor environmental pollution in real time.

show abstract

Photoswitchable Ion Receptors

Cited by 2 publications

References 69 publications

Cooperativity in Photofoldamer Chloride Double Helices Turned On with Sequences and Solvents, Around with Guests, and Off with Light

Cooperativity in Photofoldamer Chloride Double Helices Turned On with Sequences and Solvents, Around with Guests, and Off with Light

Heterocyclic Hemipiperazines: Multistimuli‐Responsive Switches and Sensors for Zinc or Cadmium Ions

Contact Info

Product

Resources

About