28950-57-4Relevant articles and documents
Controlling Dual Molecular Pumps Electrochemically
Pezzato, Cristian,Nguyen, Minh T.,Kim, Dong Jun,Anamimoghadam, Ommid,Mosca, Lorenzo,Stoddart, J. Fraser
, p. 9325 - 9329 (2018)
Artificial molecular machines can be operated using either physical or chemical inputs. Light-powered motors display clean and autonomous operations, whereas chemically driven machines generate waste products and are intermittent in their motions. Herein, we show that controlled changes in applied electrochemical potentials can drive the operation of artificial molecular pumps in a semi-autonomous manner—that is, without the need for consecutive additions of chemical fuel(s). The electroanalytical approach described in this Communication promotes the assembly of cyclobis(paraquat-p-phenylene) rings along a positively charged oligomeric chain, providing easy access to the formation of multiple mechanical bonds by means of a controlled supply of electricity.
The ionic hydrogen/deuterium bonds between diammoniumalkane dications and halide anions
Demireva, Maria,Oomens, Jos,Berden, Giel,Williams, Evan R.
, p. 995 - 1004 (2013)
Halide-anion binding to 1,12-dodecanediammonium, tetramethyl-1,12- dodecanediammmonium, and tetramethyl-1,7-heptanediammonium has been investigated with infrared multiple-photon dissociation (IRMPD) spectroscopy in the 1000-2250cm-1 spectral region and with theory. Both charged ammonium groups in these diammonium compounds interact with the halide anion resulting in an ionic hydrogen bond (IHB) stretching frequency outside of the spectral frequency range that can be measured with the free-electron laser (FEL). This frequency is shifted into the spectral range upon exchanging all of the labile hydrogen atoms with deuterium atoms, thus making measurement of the ionic deuterium bond (IDB) stretching frequency possible. The IDB stretching frequency shifts to higher values with increasing halide-anion size, methylation of the ammonium groups, and alkane chain length, consistent with the halide-anion-deuterium bond strength decreasing with decreasing gas-phase basicity of the halide anion and the increasing gas-phase basicity of the ammonium groups. The IDB stretching frequency also depends on the alkane chain length owing to constraints on the angle of the bonds between the halide anion and the two ammonium groups. There are additional bands in the IDB stretching feature in the IRMPD spectra, which are attributed to Fermi resonances and arise from coupling with overtone or combination bands that can be identified from theory and depend on the halide-anion identity and alkane chain length.
NOVEL TRISCATIONIC AMPHIPHILE COMPOUNDS, COMPOSITIONS, AND METHODS FOR MAKING SAME
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Paragraph 0170, (2017/06/12)
The inventive subject matter relates to compounds of Formula I and Formula II, compositions thereof, and processes for making such compounds as presently claimed and further described herein. The inventive compounds and compositions have antimicrobial properties and are useful as environmental disinfectants, topical cleansers such as topical personal care compositions, sanitizers, preservatives, in water treatment, as permanent or erodible coatings for medical devices and appliances, and in therapeutics.
Cleavable cationic antibacterial amphiphiles: Synthesis, mechanism of action, and cytotoxicities
Hoque, Jiaul,Akkapeddi, Padma,Yarlagadda, Venkateswarlu,Uppu, Divakara S. S. M.,Kumar, Pratik,Haldar, Jayanta
, p. 12225 - 12234 (2012/11/07)
The development of novel antimicrobial agents having high selectivity toward bacterial cells over mammalian cells is urgently required to curb the widespread emergence of infectious diseases caused by pathogenic bacteria. Toward this end, we have developed a set of cationic dimeric amphiphiles (bearing cleavable amide linkages between the headgroup and the hydrocarbon tail with different methylene spacers) that showed high antibacterial activity against human pathogenic bacteria (Escherichia coli and Staphylococcus aureus) and low cytotoxicity. The Minimum Inhibitory Concentrations (MIC) were found to be very low for the dimeric amphiphiles and were lower or comparable to the monomeric counterpart. In the case of dimeric amphiphiles, MIC was found to decrease with the increase in the spacer chain length (n = 2 to 6) and again to increase at higher spacer length (n > 6). It was found that the compound with six methylene spacers was the most active among all of the amphiphiles (MICs = 10-13 μM). By fluorescence spectroscopy, fluorescence microscopy, and field-emission scanning electron microscopy (FESEM), it was revealed that these cationic amphiphiles interact with the negatively charged bacterial cell membrane and disrupt the membrane integrity, thus killing the bacteria. All of the cationic amphiphiles showed low hemolytic activity (HC50) and high selectivity against both gram-positive and gram-negative bacteria. The most active amphiphile (n = 6) had a 10-13-fold higher HC50 than did the MIC. Also, this amphiphile did not show any cytotoxicity against mammalian cells (HeLa cells) even at a concentration above the MIC (20 μM). The critical micellar concentration (CMC) values of gemini surfactants were found to be very low (CMC = 0.30-0.11 mM) and were 10-27 times smaller than the corresponding monomeric analogue (CMC = 2.9 mM). Chemical hydrolysis and thermogravimetric analysis (TGA) proved that these amphiphiles are quite stable under both acidic and thermal conditions. Collectively, these properties make the newly synthesized amphiphiles potentially superior disinfectants and antiseptics for various biomedical and biotechnological applications.
