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Bio-oil is a valuable liquid product obtained from pyrolysis of biomass and it contains tens of hundreds of compounds, which brings about difficulties for characterization with various analytical methods. C NMR has advantages over other detection methods as it can characterize the entire composition of bio-oil and distinguish different types of carbon. But various shortcomings limit the application of C NMR. This study was carried out to develop a quantitative C NMR method to determine different functional groups in pyrolysis bio-oils with short NMR time and good accuracy, and propose a simulation of C, H, and O content for pyrolysis oils based on C NMR analysis. In order to solve long-term NMR problems, relax reagent has been added and the results show that it is an effective way to shorten the NMR time. Moreover, the aging problem is not obvious in the short-term NMR test, so the effect of aging on the test results can be neglected. Three types of substances with different oxygen content have been employed to verify the feasibility of the C, H, and O calculation methods and the result errors of all elements are small, which shows it is reliable for the simulation data of C, H and O content.
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http://dx.doi.org/10.1039/d0ra02376k | DOI Listing |
Chem Biodivers
September 2025
Department of Clinical Pharmacy, College of Pharmacy, University of Sulaimani, Sulaimani, Iraq.
The global rise in antibiotic resistance demands the urgent development of new antibacterial agents. This study investigated the antibacterial potential of four synthesized methoxy and thiophene chalcone derivatives (designated 3a, 4a, 3b, and 4b) against clinically relevant bacterial pathogens. These compounds were prepared through Claisen-Schmidt condensation, while their chemical structures were verified through applying Fourier-transform infrared, mass spectrometry, H nuclear magnetic resonance (NMR), and C NMR.
View Article and Find Full Text PDFNeurol Neuroimmunol Neuroinflamm
November 2025
Departments of Neurology and Ophthalmology, NYU Grossman School of Medicine, NY; and.
Background And Objectives: While reductions in optical coherence tomography (OCT) pRNFL and ganglion cell-inner plexiform layer thicknesses have been shown to be associated with brain atrophy in adult-onset MS (AOMS) cohorts, the relationship between OCT and brain MRI measures is less established in pediatric-onset MS (POMS). Our aim was to examine the associations of OCT measures with volumetric MRI in a cohort of patients with POMS to determine whether OCT measures reflect CNS neurodegeneration in this patient population, as is seen in AOMS cohorts.
Methods: This was a cross-sectional study with retrospective ascertainment of patients with POMS evaluated at a single center with expertise in POMS and neuro-ophthalmology.
Chem Biodivers
September 2025
Department of Biotechnology, Yeungnam University, Gyeongsan, Gyeongbuk, Republic of Korea.
One of the most significant problems facing the scientific community in the 21st century is diabetes mellitus. There is an urgent need to create new powerful compounds that can fight this terrible disease because the number of instances of diabetes and drug-resistant diabetes is rising. We have synthesized a novel series of thiazole-derived thiadiazole-based Schiff base derivatives (1-10) in an effort to identify potential antidiabetic agents.
View Article and Find Full Text PDFChem Biodivers
September 2025
Key Lab of Natural Product Chemistry and Application at Universities of Education, Department of Xinjiang Uygur Autonomous Region, School of Chemistry and Chemical Engineering, Yili Normal University, Xinjiang, China.
The persistent threat posed by phytopathogenic fungi to agricultural systems underscores the critical need for novel fungicides. Here, we synthesized and characterized a series of novel acridospiroisoxazole derivatives (H1-H36) using H/C NMR and mass spectrometry. The absolute configuration of compound H23 was confirmed using single-crystal x-ray diffraction analysis.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States.
Among the different types of HIV-1 maturation inhibitors, those that stabilize the junction between the capsid protein C-terminal domain (CA) and the spacer peptide 1 (SP1) within the immature Gag lattice are promising candidates for antiretroviral therapies. Here, we report the atomic-resolution structure of CA-SP1 assemblies with the small-molecule maturation inhibitor PF-46396 and the assembly cofactor inositol hexakisphosphate (IP6), determined by magic angle spinning (MAS) NMR spectroscopy. Our results reveal that although the two PF-46396 enantiomers exhibit distinct binding modes, they both possess similar anti-HIV potency.
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