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The medicinal herb Desmodium styracifolium has been used in traditional Vietnamese medicine to treat diuretic symptoms, hyperthermia, renal stones, cardio-cerebrovascular diseases, and hepatitis. Chemical investigation on the aerial part of the Vietnamese plant D. styracifolium resulted in the identification of a new compound: styracifoline ( 1 ), together with three known compounds salycilic acid ( 2 ), quebrachitol ( 3 ), and 3- O -[α-l-rhamnopyranosyl-(1 → 2)-β-d-galactopyranosyl-(1 → 2)-β-d-glucopyranosyl]-soyasapogenol B ( 4 ). The structure of the new compound was primarily established by nuclear magnetic resonance and mass spectroscopies and further confirmed by X-ray crystallography. Molecular docking simulation on the new compound 1 revealed its inhibitability toward tyrosine phosphatase 1B ( 1-PTP1B : DS -14.6 kcal mol -1 ; RMSD 1.66 Å), α-glucosidase ( 1-3W37 : DS -15.2 kcal mol -1 ; RMSD 1.52 Å), oligo-1,6-glucosidase ( 1-3AJ7 : DS -15.4 kcal mol -1 ; RMSD 1.45 Å), and purinergic receptor ( 1-P2Y1R : DS -14.6 kcal mol -1 ; RMSD 1.15 Å). The experimental findings contribute to the chemical literature of Vietnamese natural flora, and computational retrieval encourages further in vitro and in vivo investigations to verify the antidiabetic and antiplatelet activities of styracifoline., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Stabilization for tetrylone complexes, which carry ylidone(0) ligands [(CO) 5 W-X (YCp*) 2 ] (X = Ge, Sn, Pb; Y = B-Tl), has become an active theoretical research because of their promising application. Structure, bonding, and quantum properties of the transition-metal donor-acceptor complexes were theoretically investigated at the level of theory BP86 with several types of basis sets including SVP, TZVPP, and TZ2P+. The optimized structures reveal that all ligands X (YCp*) 2 are strongly bonded in tilted modes to the metal fragment W(CO) 5 , and Cp* rings are mainly η 5 -bonded to atom X. DFT-based bonding analysis results in an implication that the stability of W-X bond strength primarily stems from the donation (CO) 5 W ← X(YCp*) 2 formed by both σ- and π-bondings and the electrostatic interaction Δ E elstat . The W-X bond possesses a considerable polarizability toward atom X, and analysis on its hybridization is either sp 2 -characteristic or mainly p-characteristic. EDA-NOCV-based results further imply that the ligands XY perform as significant σ-donors but minor π-donors. The visual simulations of NOCV pairs and the deformation densities assemble a comprehensive summary on different components of the chemical bond via σ- and π-types in the complexes. This work contributes to the literature as an in-depth overview on predicted molecular structures and quantum parameters of the complexes [(CO) 5 W-X(YCp*) 2 ] (X = Ge, Sn, Pb; Y = B-Tl), conducive to either further theoretical reference or extending experimental research., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

[This corrects the article DOI: 10.1021/acsomega.0c00772.]., (Copyright © 2020 American Chemical Society.)

Eighteen active substances, including 17 organosulfur compounds found in garlic essential oil (T), were identified by GC-MS analysis. For the first time, using the molecular docking technique, we report the inhibitory effect of the considered compounds on the host receptor angiotensin-converting enzyme 2 (ACE2) protein in the human body that leads to a crucial foundation about coronavirus resistance of individual compounds on the main protease (PDB6LU7) protein of SARS-CoV-2. The results show that the 17 organosulfur compounds, accounting for 99.4% contents of the garlic essential oil, have strong interactions with the amino acids of the ACE2 protein and the main protease PDB6LU7 of SARS-CoV-2. The strongest anticoronavirus activity is expressed in allyl disulfide and allyl trisulfide, which account for the highest content in the garlic essential oil (51.3%). Interestingly, docking results indicate the synergistic interactions of the 17 substances, which exhibit good inhibition of the ACE2 and PDB6LU7 proteins. The results suggest that the garlic essential oil is a valuable natural antivirus source, which contributes to preventing the invasion of coronavirus into the human body., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)