98%
921
2 minutes
20
Control of the formation of liquid crystalline 3̄ gyroid phases and their nanostructures is critical to advance materials chemistry based on the structural feature of three-dimensional helical networks. Here, we present that introducing methyl side-group(s) and slight non-symmetry into aryloyl-hydrazine-based molecules is unexpectedly crucial for their formation and can be a new design strategy through tuning intermolecular interactions: the two chemical modifications in the core portion of the chain-core-chain type molecules effectively lower and extend the 3̄ phase temperature ranges with the increased twist angle between neighboring molecules along the network. The detailed analyses of the aggregation structure revealed the change in the core assembly mode from the double-layered core mode of the mother molecule (without methyl groups) to the single-layered core mode. Such changes are explained in terms of modified intermolecular interactions in those phases employing quantum chemical calculations.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1039/d4cp03919j | DOI Listing |
J Chem Phys
July 2025
Center for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India.
Protamine, an arginine-rich protein, compacts DNA more tightly than histones in somatic cells, yet its sequence-specific binding remains unclear. Using all-atom MD simulations with an arginine-rich short cationic peptide that mimics the protamine characteristics, we discovered distinct sequence preferences: the peptide binds preferentially to GC-rich sequences in the major groove and AT-rich sequences in the minor groove. Our structural analysis reveals that GC-rich binding induces significant DNA bending, narrowing the major groove and enhancing peptide interactions.
View Article and Find Full Text PDFACS Chem Neurosci
July 2025
Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts 02115, United States.
We have characterized families of phenylpiperazine (PP) compounds, studying their relative activity with α7 and α9* nicotinic acetylcholine receptors (nAChRs) and focusing on the effects of side groups on the phenyl ring (R) and the effects of different alkyl groups on the base nitrogen. In this study, we evaluated the impact of methyl substitution on the piperazine ring, which introduced a chiral center, enabling the generation and separation of stereoisomers. Methyl groups were added to either the C2 or C3 positions on the piperazine of the α9α10 agonist/α7 partial agonist PA-EMPP.
View Article and Find Full Text PDFJ Am Chem Soc
April 2025
Hefei National Laboratory for Physical Science at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
The recognition and differentiation of organic amines are crucial for applications in drug analysis, food spoilage, biomedical assays, and clinical diagnostics. Existing luminescence-based recognition methods for amines predominantly rely on fluorescence quenching, limiting the scope of sensitive and selective detection. Here, we present a fluorochromic approach for rapidly distinguishing different organic amines based on their unique excited-state and ground-state interactions with a naphthalimide derivative under ultraviolet light.
View Article and Find Full Text PDFMacromol Rapid Commun
June 2025
Department of Materials Science and Engineering, School of Materials and Chemical Technology, Institute of Science Tokyo, S8-36 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8552, Japan.
Owing to their low dielectric constant (D), processability, and mechanical properties, siloxane-based polymers have attracted attention as insulating materials for next-generation communication. However, a major challenge regarding siloxane-containing materials is their high dielectric loss tangent (dissipation factor) (D). A polymer is designed and synthesized by combining polysiloxanes with phenyl side groups on the main chain and a polyimide structure (polysiloxane-imide) to improve the D value.
View Article and Find Full Text PDFBiomacromolecules
April 2025
School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300350, China.
Controlling ice growth is crucial during the cryopreservation of cells, but the current application of small molecules as cryoprotectants still remains a challenge. Inspired by structures of natural antifreeze (glyco)proteins, in this work, functionalized poly(l-methionine)s (PMets) are synthesized with different side groups including hydroxyl, threonine-mimetic with both methyl and hydroxyl groups (PMet-MOH), zwitterion with carboxyl and sulfonium (PMet-COOH), glycerol, and trehalose pendants. Results suggest that these functionalized PMets tend to self-assemble into 100-300 nm nanoparticles with positive charges in water.
View Article and Find Full Text PDF