The Biginelli reaction was combined with the Passerini reaction for the first time in a sequential multicomponent tandem reaction approach. After evaluation of all possible linker components and a suitable solvent system, highly functionalized dihydropyrimidone-α-acyloxycarboxamide compounds were obtained in good to excellent yields. In a first reaction step, different 3,4-dihydropyrimidin-2(1)-one acids were synthesized, isolated and fully characterized. These products were subsequently used in a Passerini reaction utilizing a dichloromethane/dimethyl sulfoxide solvent mixture. By variation of the components in both multicomponent reactions, a large number of structurally diverse compounds could be synthesized. In addition, a one-pot Biginelli-Passerini tandem reaction was demonstrated. All products were carefully characterized via 1D and 2D NMR as well as IR and HRMS.
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http://dx.doi.org/10.3762/bjoc.13.7 | DOI Listing |
J Am Chem Soc
January 2025
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China.
Chirality epitomizes the sophistication of chemistry, representing some of its most remarkable achievements. Yet, the precise synthesis of chiral structures from achiral building blocks remains a profound and enduring challenge in synthetic chemistry and materials science. Here, we demonstrate that achiral colloidal nanocrystals, including Au and Ag nanocrystals, can assemble into long-range-ordered helical assemblies with the assistance of chiral molecules.
View Article and Find Full Text PDFMicrosc Res Tech
January 2025
School of Electrical & Control Engineering, Shenyang Jianzhu University, Shenyang, China.
The atomic force microscope (AFM) image will be inclined and bent due to the tilt angle between the probe and the sample surface. When the least squares fitting method is used to correct the horizontal distortion of the AFM image, the shape structure that is lower or higher than the sample base will affect the final fitting correction result. In view of the limitations of existing methods and the diversity of AFM images, an AFM image level distortion correction method based on automatic feature marking is proposed.
View Article and Find Full Text PDFMol Ecol
January 2025
ECNU-Alberta Joint Lab for Biodiversity Study, Tiantong Forest Ecosystem National Observation and Research Station, School of Ecology and Environmental Sciences, East China Normal University, Shanghai, China.
Plant microbiomes have a major influence on forest structure and functions, as well as tree fitness and evolution. However, a comprehensive understanding of variations in fungi along the soil-plant continuum, particularly within tree seedlings, under global warming is lacking. Here, we investigated the dynamics of fungal communities across different compartments (including bulk soil and rhizosphere soil) and plant organs (including the endosphere of roots, stems and leaves) of Schima superba seedlings exposed to experimental warming and drought using AccuITS absolute quantitative sequencing.
View Article and Find Full Text PDFBiochem Mol Biol Educ
January 2025
Heritage University, Toppenish, Washington, USA.
The impact of Covid-19 pandemic has dramatically shifted the education landscape between recent college and university graduates and pathways to graduate degrees. In my perspective article, I wish to share the challenges, reflections, and a call-to-action framework in ways we can support and advocate for postbaccalaureate persons excluded because of their ethnicity of race, or from a structurally marginalized community or PEERS through the lens of mindfulness, humility, reflection, and deep listening. Through cross-institutional community network support, culturally responsive mentoring of postbaccalaureate PEERS is one of the key dimensions in empowering communities toward health, environmental, and social justice.
View Article and Find Full Text PDFBiosci Microbiota Food Health
August 2024
Central Research Institute, Itoen Ltd., 21 Mekami, Sagara-cho, Haibara-gun, Shizuoka, Japan.
Probiotics exert their beneficial effects by improving the intestinal environment. Heat-inactivated probiotics may show similar effects. However, whether multi-strain mixtures (MSM) are better than single strains, irrespective of whether the bacteria are alive or dead, is unknown.
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