We report the synthesis of -symmetric cryptophanes decorated with three aromatic amine groups on the same CTB cap and their interaction with xenon. The relative stereochemistry of these two stereoisomers and was assessed thanks to the determination of the X-ray structure of an intermediate compound. As previously observed with the tris-aza-cryptophanes analogs - and - (. , , 11, 7648-7658), both compounds - and - show a slow in-out exchange dynamics of xenon at 11.7 T. Our work supports the idea that the presence of nitrogen atoms grafted directly onto the cryptophane backbone has a strong impact on the in-out exchange dynamics of xenon whatever their stereochemistry. This result contrasts with the case of other cryptophanes decorated solely with methoxy substituents. Finally, we demonstrate that these new derivatives can be used to design new / cryptophanes bearing suitable ligands in order to constitute potent Xe NMR-based sensors. An example is reported here with the synthesis of the tris-iodo derivatives - and - from compounds - and -.
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http://dx.doi.org/10.1021/acs.joc.1c02774 | DOI Listing |
Polymers (Basel)
December 2024
Key Laboratory for Special Area Highway Engineering of Ministry of Education, Chang'an University, South 2nd Ring Road Middle Section, Xi'an 710064, China.
Studying the mechanisms and effects of rejuvenators on SBS-modified bitumen is crucial for repairing degraded SBS and recycling aged SBS-modified bitumen (ASMB), thereby contributing to the sustainable development of bitumen pavements. This research examines the roles of mono-epoxy Alkyl (C12-C14) glycidyl ether (AGE) and di-epoxy 1,6-Hexanediol diglycidyl ether (HDE) under the catalysis of N,N-dimethyl benzyl amine (BDMA) in repairing degraded SBS chains. Aromatic oil (ORSMB)-, AGE-aromatic oil (ARSMB)-, and HDE-aromatic oil (HRSMB)-rejuvenated bitumen are analyzed for their chemical structures, physical properties, and rheological properties.
View Article and Find Full Text PDFEnviron Monit Assess
January 2025
Department of Civil and Environmental Engineering, Babol Noshirvani University of Technology, Babol, Iran.
Water contamination by polycyclic aromatic hydrocarbons (PAHs), particularly naphthalene, is a serious environmental concern due to its persistence, bioaccumulation, and toxicity. This study explores the adsorption behavior of naphthalene using organobentonite (OBt), synthesized by intercalating cetyltrimethylammonium bromide (CTAB) into sodium bentonite (SBt) with varying cation exchange capacities (CECs). The effectiveness of OBt in naphthalene adsorption was evaluated by analyzing key parameters, including CEC, contaminant concentration, and contact time.
View Article and Find Full Text PDFFood Res Int
January 2025
School of Food Science and Engineering, Ministry of Education Engineering Research Center of Starch and Protein Processing, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510640, China; Modern Industrial Technology Research Institute, South China University of Technology, Zhongshan 528437, China. Electronic address:
Our previous research discovered that myricetin could effectively inhibit the formation of heterocyclic aromatic amines (HAAs) in cantonese baked foods by trapping phenylacetaldehyde to form adducts. However, the structure and biological activity of these adducts were still unknown. In this study, we identified two myricetin-phenylacetaldehyde adducts from cantonese mooncakes, BYQ-2 and BYQ-3, using pre-HPLC.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
January 2025
Oligometrics, Inc., 2510 47th Street, Suite 208, Boulder, CO, 80301, USA.
The X-ray crystal structure of a multi-aromatic substituted 1,2,3-triazole is presented, which shows an extensive three-dimensional hydrogen-bonding network involving two water mol-ecules and two aceto-nitrile mol-ecules. The structure of 4-{[(4-{[1-({[(3,4-di-meth-oxy-phen-yl)meth-yl](3-acetamido-phen-yl)carbamo-yl}meth-yl)-1-1,2,3-triazol-4-yl]meth-oxy}-3-meth-oxy-phen-yl)meth-yl]amino}-benzoic acid-aceto-nitrile-water (1/2/2), CHNO·2CHN·2HO, features amine-linked aromatic groups that have a variety functionality including a carb-oxy-lic acid, an acetamido group, and meth-oxy ethers. All -H groups, and seven out of ten heteroatoms with available lone-pair electrons, participate in hydrogen bonding, with the aid of dimer-bridging water mol-ecules and aceto-nitrile mol-ecules whose methyl groups form close contacts with oxygen atoms.
View Article and Find Full Text PDFChem Asian J
January 2025
University of Kerala, Department of Chemistry, Kariavattom Campus, 695581, Thiruvananthapuram, INDIA.
Crystallinity, stability, and complexity are significant factors to consider in the design and development of covalent organic frameworks (COFs). Among various building blocks used, 1,3,5-triformylphloroglucinol (Tp) is notable for enhancing both crystallinity and structural stability in COFs. Tp facilitates the formation of β-ketoenamine-linked COFs through keto-enol tautomerism when reacted with aromatic amines.
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