Analysis of sodium, potassium, calcium, and ammonium cation binding and selectivity in one- and two-armed nitrogenpivot lariat ethers

Arnold, Kristin A.; Hernandez, Jeanette C.; Li, Chensheng; Mallen, Jesus; Nakano, Akio; Schall, Otto F.; Trafton, John E.; Tsesarskaja, Mara; White, Brandyn; Gokel, George W.

doi:10.1080/10610279508029887

Cited by 29 publications

(15 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The equilibrium binding constant for sodium cation complexation in methanol solution in the former case was ∼12 000 compared to the urethane-linked compounds: K < 30. 30 Despite their overall similarity in structure to the alkyl derivatives, the two macrocycles having amide side chains (7 and 8) proved to be inactive to all three organisms tested in these studies.…”

Section: Hydrophobicity Of 1-8mentioning

confidence: 86%

See 1 more Smart Citation

Correlation of bilayer membrane cation transport and biological activity in alkyl-substituted lariat ethers

et al. 2005

Self Cite

View full text Add to dashboard Cite

Dialkyldiaza-18-crown-6 lariat ethers having twin n-octyl, n-decyl, n-dodecyl, n-tetradecyl, nhexadecyl, 1-oxodecyl and 1-oxododecyl side arms were prepared and studied. Cation transport in liposomes mediated by these compounds showed discontinuous activity that correlated with toxicity to the bacteria E. coli and B. Subtilis, and theyeast S. Cerevisiae. Transport, toxicity and membrane depolarization studies all suggest that side chain length affords very different interactions in a bilayer membrane compared with bulk phases. An explanation for activity in terms of carrier transport and restricted transverse relaxation is proposed.

show abstract

Section: Hydrophobicity Of 1-8mentioning

confidence: 86%

“…When the sidearms were propyl, butyl, hexyl, nonyl or dodecyl, the binding constants (log 10 K S ) were all 2.9 ± 0.1. 30 Based on the binding and hydrophobicity data, we anticipated that any change in biological activity would be small and gradual, if not linear.…”

Section: Hydrophobicity Of 1-8mentioning

confidence: 99%

Correlation of bilayer membrane cation transport and biological activity in alkyl-substituted lariat ethers

et al. 2005

Self Cite

View full text Add to dashboard Cite

show abstract

“…Crown ethers are, of course, cation selective and it was thought that some selectivity would be imposed on the system if cations used the crown as an entry portal. N,N'-Di-n-dodecyl-4,13-diaza-18-crown-6 binds Na + and K + in CH 3 OH solution with constants Ks (log Ks) of 980 (2.99) and 6300 (3.80) [52]. This is a selectivity of about 6:1 for K + >Na + .…”

Section: Design Criteria For Hydraphilesmentioning

confidence: 96%

Coordination and transport of alkali metal cations through phospholipid bilayer membranes by hydraphile channels

Gokel

Daschbach

2008

Coordination Chemistry Reviews

Self Cite

View full text Add to dashboard Cite

Hydraphiles are synthetic ionophores that were designed to mimic some properties of protein channels that conduct such cations as sodium. They use macrocyclic (crown) polyethers as amphiphilic headgroups and as entry and exit portals. Their overall length is controlled by covalent links between the two headgroups (distal macrocycles) and the "central relay" unit, typically also an azacrown. The hydraphiles insert in the bilayer membranes of synthetic phospholipid vesicles or vital cells and mediate the transport of cations. The hydraphiles were intended to be models but they are functional channels. Because they are symmetric, they are non-rectifying but they show open-close behavior characteristic of natural channels. Because they are non-rectifying, when they insert into a microbial membrane, they lead to a rapid change in osmotic balance that proves fatal to bacteria.

show abstract

“…Of course, when the amide is present in a sidearm that can serve as a lariat ether donor, the effect is favorable. 24…”

Section: Cation Binding Data For Macrocyclic Lactams and Lactonesmentioning

confidence: 99%

The influence of varied amide bond positions on hydraphile ion channel activity

et al. 2006

Self Cite

View full text Add to dashboard Cite

Hydraphile compounds have been prepared in which certain of the amine nitrogens have been replaced by amide residues. The amide bonds are present either in the sidearm, the side chain, or the central relay. Sodium cation transport through phospholipid vesicles mediated by each hydraphile was assessed. All of the amide-containing hydraphiles showed increased levels of Na + transport compared to the parent compound, but the most dramatic rate increase was observed for sidearm amine to amide replacement. We attribute this enhancement to stabilization of the sidearm in the bilayer to achieve a better conformation for ion conduction. Biological studies of the amide hydraphiles with E. coli and B. subtilis showed significant toxicity only with the latter. Further, the consistency between the efficacies of ion transport and toxicity previously observed for non-amidic hydraphiles was not in evidence.

show abstract

Analysis of sodium, potassium, calcium, and ammonium cation binding and selectivity in one- and two-armed nitrogenpivot lariat ethers

Cited by 29 publications

References 42 publications

Correlation of bilayer membrane cation transport and biological activity in alkyl-substituted lariat ethers

Correlation of bilayer membrane cation transport and biological activity in alkyl-substituted lariat ethers

Coordination and transport of alkali metal cations through phospholipid bilayer membranes by hydraphile channels

The influence of varied amide bond positions on hydraphile ion channel activity

Contact Info

Product

Resources

About