Supported ionic-liquid films (SILF) of nanometric thickness containing bis(oxazoline)-copper complexes can be used as recoverable catalysts for enantioselective cyclopropanation reactions. When a thin film of ionic liquid is supported on a clay, the system behaves as a nearly two-dimensional nanoreactor in which the restrictions in rotational mobility and the close proximity to the surface support produce variations in the stereo- and enantioselectivities, leading to a complete reversal of the overall selectivity of the reaction. As an example, the cyclopropanation of styrene changes from a preference for the (1S,2S)-trans isomer in bulk solution to the (1R,2S)-cis isomer in the SILF. This variation is strongly dependent on both the thickness of the film and the nature of the support. Only layered solids with negative charges in the layers (clays) give rise to this type of behaviour, showing that the formation of ion pairs may be a decisive factor. This unexpected effect also shows the existence of differences between bulk and supported ionic liquids.
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Int J Pharm
January 2025
School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 51006 China. Electronic address:
Androgenic alopecia (AGA), the most prevalent type of progressive hair loss, currently lacks an effective topical treatment regimen. In this study, we synthesized an ionic liquid (IL) to co-solubilize minoxidil (MXD) and finasteride (FIN) and subsequently formulated them into an in situ thermosensitive ionic liquid/cyclodextrin/poloxamer hydrogel (ICPG), termed M + F@ICPG. M + F@ICPG was developed for the transdermal co-delivery of these two drugs, aiming to provide a multipath therapeutic approach for AGA while avoiding the adverse effects commonly associated with oral FIN and topical MXD tincture.
View Article and Find Full Text PDFBiosensors (Basel)
January 2025
Department of Chemistry and Materials, Faculty of Textile Science and Technology, Shinshu University, 3-15-1 Tokida, Ueda 386-8567, Nagano, Japan.
Nitrogen-based fertilizers are crucial in agriculture for maintaining soil health and increasing crop yields. Soil microorganisms transform nitrogen from fertilizers into NO3--N, which is absorbed by crops. However, some nitrogen is converted to nitrous oxide (NO), a greenhouse gas with a warming potential about 300-times greater than carbon dioxide (CO).
View Article and Find Full Text PDFOrg Biomol Chem
January 2025
Department of Chemistry, Rabindranath Tagore University, Hojai 782435, Assam, India.
The synthesis of triazoles plays an important role in drug discovery research. 1,2,4-triazoles are considered significant scaffolds among several bioactive heterocycles due to their extensive use in the pharmaceutical and agrochemical sectors. Consequently, the importance of the synthesis of 1,2,4-triazoles a sustainable method has increased.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh, 11451, Saudi Arabia.
Growing emission of environmentally-hazardous greenhouse pollutants (especially CO) has motivated the researchers to apply gas-liquid membrane contactors as an easy-to-operate and cost-effective technique for increasing their separation efficiency from different sources. In the current decades, ionic liquids (ILs) have shown their potential in the gas separation industry owing to their noteworthy advantages such as great capacity, excellent adjustability and suitable thermal/chemical stability compared to commonly-employed amine absorbents. This investigation aims to analytically/numerically determine the separation yield of CO from CO₂/N gaseous flow using novel -Ethyl-3-methylimidazolium dicyanamide ([emim][CN]) IL inside the gas-liquid contactor.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Institute of Advanced Wear & Corrosion Resistant and Functional Materials, Jinan University, Guangzhou 510632, China.
As a type of century-old catalyst, the use of iron-based materials runs through the Haber-Bosch process and electrochemical synthesis of ammonia because of its excellent capability, low cost, and abundant reserves. How to continuously improve its catalytic activity and stability for electrochemical nitrogen fixation has always been a goal pursued by scientific researchers. Herein, we develop a free-standing iron-based catalyst, i.
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