The relationship between the crystal packing of powder samples and long-range (13)C-(13)C homonuclear dipolar couplings is presented and illustrated for the case of uniformly (13)C-enriched L-alanine and L-histidine·HCl·H2O. Dipolar coupling measurement is based on the partial reintroduction of dipolar interactions by spinning the sample slightly off-magic-angle, while the coupling of interest for a given spin pair is isolated with a frequency-selective pulse. A cost function is used to correlate the so-derived dipolar couplings to trial crystal structures of the samples under study. This procedure allowed for the investigation of the l-alanine space group and L-histidine·HCl·H2O space group and unit-cell parameters.
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http://dx.doi.org/10.1016/j.ssnmr.2014.12.003 | DOI Listing |
Acta Crystallogr C Struct Chem
February 2025
Institute of Applied Chemistry, Shanxi University, Wucheng, Taiyuan, Shanxi 030006, People's Republic of China.
Three bisferrocene-based bis(acylthiourea) positional isomers, namely, 1,2-bis(ferrocenylcarbonylthioureido)benzene (1), 1,3-bis(ferrocenylcarbonylthioureido)benzene (2) and 1,4-bis(ferrocenylcarbonylthioureido)benzene (3), all [Fe(CH)(CHNOS)], have been synthesized via facile nucleophilic addition reactions of 2.3 equivalents of ferrocenoyl isothiocyanate with o-, m- and p-phenylenediamine, respectively. The structures of the three new synthesized isomers were fully characterized by H NMR, C NMR, IR and UV-Vis spectroscopy, elemental analyses and cyclic voltammetry.
View Article and Find Full Text PDFJ Trace Elem Med Biol
January 2025
Center for Global Health Research (CGHR), Saveetha Medical College, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, India. Electronic address:
[CuL(tmen)] is a sequence of four ternary mononuclear Schiff base copper(II) complexes that are derived from L-valine, suitable 5'-substituted-2'-hydroxyacetophenones (where the substituents are -Cl for L, -Me for L, -OMe for L, and -H for L), and tmen (where tmen-N,N,N',N' tetramethyl ethylenediamine). Without isolating the Schiff base ligand or producing any other intermediate products, all of the complexes were synthesised. These compounds were identified using elemental analysis, molar conductance, UV-Vis, FTIR, EPR, VSM-RT, and CD spectra.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Chemistry and Centre for Processable Electronics, Imperial College London, London, W12 0BZ, UK.
Most current highly efficient organic solar cells utilize small molecules like Y6 and its derivatives as electron acceptors in the photoactive layer. In this work, a small molecule acceptor, SC8-IT4F, is developed through outer side chain engineering on the terminal thiophene of a conjugated 6,12-dihydro-dithienoindeno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene (IDTT) central core. Compared to the reference molecule C8-IT4F, which lacks outer side chains, SC8-IT4F displays notable differences in molecule geometry (as shown by simulations), thermal behavior, single-crystal packing, and film morphology.
View Article and Find Full Text PDFSmall
January 2025
Institute of Translational Medicine, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, China.
In this study, we present an ultrasensitive and specific multiplexed detection method for SARS-CoV-2 and influenza (Flu) utilizing CRISPR/Cas13a technology combined with a hydrogel-encapsulated photonic crystal (PhC) barcode integrated with hybridization chain reaction (HCR). The barcodes, characterized by core-shell structures, are fabricated through partial replication of periodically ordered hexagonally close-packed silicon dioxide beads. Consequently, the opal hydrogel shell of these barcodes features abundant interconnected pores that provide a substantial surface area for probe immobilization.
View Article and Find Full Text PDFOrg Lett
January 2025
Department of Materials Science, State Key Laboratory of Molecular Engineering of Polymers, Laboratory of Molecular Materials and Devices, Fudan University, Shanghai 200433, China.
Two series of polycyclic aromatic hydrocarbon isomers ( and , and and ) were designed and synthesized by isomerically fusing phenanthrene with thiophene and thieno[3,2-]thiophene, respectively. All of the new target molecules were confirmed by single-crystal X-ray analysis, and it was found that the solid-state packing can be effectively modulated through a combination of π-extended and isomeric fused strategies. Meanwhile, compared with thiophene ring-terminated isomers and , both having a V-shaped geometry and showing no obvious self-assembly behavior, π-extended unit thieno[3,2-]thiophene-terminated isomer displays a V-shaped structure with moderate self-assembly properties and isomer exhibits a C-shaped configuration with further enhanced self-assembly properties.
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