Modulating bioactivities of primary ammonium-tagged antimicrobial aliphatic polycarbonates by varying length, sequence and hydrophobic side chain structure

2019 ◽  
Vol 7 (6) ◽  
pp. 2288-2296 ◽  
Author(s):  
Kazuki Fukushima ◽  
Kohei Kishi ◽  
Keita Saito ◽  
Kazuki Takakuwa ◽  
Shunta Hakozaki ◽  
...  

A highly antimicrobial, biocompatible, and fast biodegradable polycarbonate has been developed by incorporating primary ammonium and monoether side chains.

Biochemistry ◽  
1999 ◽  
Vol 38 (10) ◽  
pp. 2947-2955 ◽  
Author(s):  
Hassane S. Mchaourab ◽  
Tamás Kálai ◽  
Kálmán Hideg ◽  
Wayne L. Hubbell

Biochemistry ◽  
2001 ◽  
Vol 40 (13) ◽  
pp. 3828-3846 ◽  
Author(s):  
Linda Columbus ◽  
Támás Kálai ◽  
József Jekö ◽  
Kálmán Hideg ◽  
Wayne L. Hubbell

2015 ◽  
Vol 3 (13) ◽  
pp. 7077-7085 ◽  
Author(s):  
Jianyu Yuan ◽  
Wanli Ma

The number of conjugated side chains on the donor polymer can greatly affect the performance of all-polymer solar cells.


1958 ◽  
Vol 36 (10) ◽  
pp. 1037-1045 ◽  
Author(s):  
D. Wright ◽  
Stewart A. Brown ◽  
A. C. Neish

A number of aromatic compounds having carbon side chains of varying length and substitution have been studied as lignin precursors. p-Hydroxybenzaldehyde was poorly utilized, indicating that the formation of C6,C3 units from a condensation of C6,C1, and C2 fragments is of very limited significance. The C6,C2 compound, mandelic acid, was not converted to lignin. DL-Phenyllactic acid was incorporated into lignin with much lower dilution than either DL-erythro- or DL-threo-phenylglyceric acids, and with appreciably lower dilution than DL-phenylhydracrylic acid, supporting the concept that lignin monomers are formed via 2-hydroxylated phenylpropane intermediates. Wheat utilized the D-form of phenylalanine less readily than the L-form. Although three monocotyledons tested could utilize (+)- and (−)-phenyllactic acid to a comparable degree, two dicotyledons showed a marked preference for the (−)-form, suggesting that in dicotyledons the enzyme system specific for the (−)-form is predominant.


RSC Advances ◽  
2015 ◽  
Vol 5 (83) ◽  
pp. 67718-67726 ◽  
Author(s):  
Shang-Che Lan ◽  
Chiao-Kai Chang ◽  
Yueh-Hsin Lu ◽  
Shu-Wei Lin ◽  
Alex K.-Y. Jen ◽  
...  

Small molecules with alkyl side chains of different lengths were prepared with 2,2′-bithiophene, terthiophene and thiobarbituric acid as the central core, spacer and end-cap. Uniform, shorter chain lengths gave stronger intermolecular interactions, favoring crystallization.


1958 ◽  
Vol 36 (1) ◽  
pp. 1037-1045 ◽  
Author(s):  
D. Wright ◽  
Stewart A. Brown ◽  
A. C. Neish

A number of aromatic compounds having carbon side chains of varying length and substitution have been studied as lignin precursors. p-Hydroxybenzaldehyde was poorly utilized, indicating that the formation of C6,C3 units from a condensation of C6,C1, and C2 fragments is of very limited significance. The C6,C2 compound, mandelic acid, was not converted to lignin. DL-Phenyllactic acid was incorporated into lignin with much lower dilution than either DL-erythro- or DL-threo-phenylglyceric acids, and with appreciably lower dilution than DL-phenylhydracrylic acid, supporting the concept that lignin monomers are formed via 2-hydroxylated phenylpropane intermediates. Wheat utilized the D-form of phenylalanine less readily than the L-form. Although three monocotyledons tested could utilize (+)- and (−)-phenyllactic acid to a comparable degree, two dicotyledons showed a marked preference for the (−)-form, suggesting that in dicotyledons the enzyme system specific for the (−)-form is predominant.


Soft Matter ◽  
2016 ◽  
Vol 12 (7) ◽  
pp. 1983-1988 ◽  
Author(s):  
Sunyoung Lee ◽  
Yooseong Yang ◽  
Sunchul Kwon ◽  
Youngsuk Jung

The side chain structure plays a critical role in the orientation propagation of an aligned seed layer into the bulk of the polyfluorene film by heating into its nematic melt state.


2020 ◽  
Author(s):  
Julian Keupp ◽  
Johannes P. Dürholt ◽  
Rochus Schmid

The prototypical pillared layer MOFs, formed by a square lattice of paddle-<br>wheel units and connected by dinitrogen pillars, can undergo a breathing phase<br>transition by a “wine-rack” type motion of the square lattice. We studied this not<br>yet fully understood behavior using an accurate first principles parameterized force<br>field (MOF-FF) for larger nanocrystallites on the example of Zn 2 (bdc) 2 (dabco) [bdc:<br>benzenedicarboxylate, dabco: (1,4-diazabicyclo[2.2.2]octane)] and found clear indi-<br>cations for an interface between a closed and an open pore phase traveling through<br>the system during the phase transformation [Adv. Theory Simul. 2019, 2, 11]. In<br>conventional simulations in small supercells this mechanism is prevented by periodic<br>boundary conditions (PBC), enforcing a synchronous transformation of the entire<br>crystal. Here, we extend this investigation to pillared layer MOFs with flexible<br>side-chains, attached to the linker. Such functionalized (fu-)MOFs are experimen-<br>tally known to have different properties with the side-chains acting as fixed guest<br>molecules. First, in order to extend the parameterization for such flexible groups,<br>1a new parametrization strategy for MOF-FF had to be developed, using a multi-<br>structure force based fit method. The resulting parametrization for a library of<br>fu-MOFs is then validated with respect to a set of reference systems and shows very<br>good accuracy. In the second step, a series of fu-MOFs with increasing side-chain<br>length is studied with respect to the influence of the side-chains on the breathing<br>behavior. For small supercells in PBC a systematic trend of the closed pore volume<br>with the chain length is observed. However, for a nanocrystallite model a distinct<br>interface between a closed and an open pore phase is visible only for the short chain<br>length, whereas for longer chains the interface broadens and a nearly concerted trans-<br>formation is observed. Only by molecular dynamics simulations using accurate force<br>fields such complex phenomena can be studied on a molecular level.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1789
Author(s):  
Dmitry Tolmachev ◽  
George Mamistvalov ◽  
Natalia Lukasheva ◽  
Sergey Larin ◽  
Mikko Karttunen

We used atomistic molecular dynamics (MD) simulations to study polyelectrolyte brushes based on anionic α,L-glutamic acid and α,L-aspartic acid grafted on cellulose in the presence of divalent CaCl2 salt at different concentrations. The motivation is to search for ways to control properties such as sorption capacity and the structural response of the brush to multivalent salts. For this detailed understanding of the role of side-chain length, the chemical structure and their interplay are required. It was found that in the case of glutamic acid oligomers, the longer side chains facilitate attractive interactions with the cellulose surface, which forces the grafted chains to lie down on the surface. The additional methylene group in the side chain enables side-chain rotation, enhancing this effect. On the other hand, the shorter and more restricted side chains of aspartic acid oligomers prevent attractive interactions to a large degree and push the grafted chains away from the surface. The difference in side-chain length also leads to differences in other properties of the brush in divalent salt solutions. At a low grafting density, the longer side chains of glutamic acid allow the adsorbed cations to be spatially distributed inside the brush resulting in a charge inversion. With an increase in grafting density, the difference in the total charge of the aspartic and glutamine brushes disappears, but new structural features appear. The longer sides allow for ion bridging between the grafted chains and the cellulose surface without a significant change in main-chain conformation. This leads to the brush structure being less sensitive to changes in salt concentration.


Sign in / Sign up

Export Citation Format

Share Document