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Distichochlamys citreaM.F. Newman, a genus endemic to Vietnam, has been known by folk experiences for its biological potential, including antidiabetics. The essential oil was extracted and characterized by gas chromatography‐mass spectrometry for compositional specificity. The data was used as input for computational predictions. Gas chromatography‐mass spectrometry analysis revealed the presence of 23 natural components in the essential oil (C1‐C23); major constituents: α‐citral (C16; 21.19%), cineole (C7; 16.11%), β‐citral (C14; 16.03%), geranyl acetate (C20; 15.97%), geraniol (C15; 10.74%). Density functional theory calculation suggests C14and C15highly promising for intermolecular interactions by on their electronic configurations. Molecular docking simulation predicts the most effective inhibitors against PDB‐3AJ7 (oligo‐1,6‐glucosidase) into the order of ligand‐protein complexes: C15‐3AJ7(DS ‐11.9 kcal.mol‐1) ≈ C14‐3AJ7(DS ‐11.8 kcal.mol‐1) > C12‐3AJ7(DS ‐11.5 kcal.mol‐1) > C11‐3AJ7(DS ‐11.2 kcal.mol‐1) > C9‐3AJ7(DS ‐11.0 kcal.mol‐1). All the components are expected to be biocompatible (by QSARIS physical properties) and safe for medicinal use (by ADMET pharmacokinetics and pharmacology). Altogether, the results encourage further consideration of D. citreaM.F. Newman essential oil for further wet antidiabetic tests, especially the specification on C14(aka. β‐Citral) and C15(aka. Geraniol).

Flavonoidal derivatives sinensetin (F1), isoorientin (F2), naringenin (F3), morin (F4), daidzein (F5) were experimentally demonstrated with effectiveness against Helicobacter pylori, thus speculated for their inhibitory effects towards structures of mucin‐5AC protein (UniProtKB‐P98088) and urease (PDB‐1E9Z),and subjected for in silicoinvestigations. Their quantum properties were examined using density functional theory (DFT). The ligand‐protein inhibitability was evaluated using molecular docking simulation. Physicochemical properties were obtained from QSARIS‐based analysis in reference to Lipinski's rule of five. Pharmacokinetic parameters were assessed by ADMET‐based analysis. DFT calculations indicate that there are no abnormal bonding constraints observed. NBO analysis suggests F2and F4possessing favourable electric configurations for intermolecular inhibition. Regarding ligand‐P98088, the order for static inhibitability is F2‐P98088> F4‐P98088> F3‐P98088> F5‐P98088> F1‐P98088. Regarding ligand‐1E9Z, the corresponding order follows: F2‐1E9Z≈ F4‐1E9Z> F5‐1E9Z> F3‐1E9Z≈ F1‐1E9Z. QSARIS‐based analysis reveals that all the candidates are highly bio‐compatible. ADMET‐based analysis specifies F2as being safe and suitable for the use as orally administrated drugs. The results encourage further investigations for more in‐depth mechanisms and experimental validations, such as in vitroenzyme assays or clinical trials.

Baloxavir marboxil (D1), Baricitinib (D2), Galidesivir (D3), Nitazoxanide (D4), and Oseltamivir (D5) are well‐known performing broad‐spectrum activity against a variety of viruses, thus holding high potentiality towards SARS‐CoV‐2. Quantum properties were examined using density functional theory (DFT). The inhibitability of the drugs towards Angiotensin‐converting enzyme 2 (ACE2) and SARS‐CoV‐2 main protease (6LU7) was evaluated by molecular docking simulation, while their bio‐compatibility was justified by physicochemical properties obtained from QSARIS‐based analysis in reference to Lipinski's rule of five. Quantum analysis suggests that the compounds are highly favourable for intermolecular interaction towards protein structures. Given ligand‐ACE2 systems, the inhibitory effectiveness follows the order D3‐ACE2> D4‐ACE2> D2‐ACE2> D5‐ACE2> D1‐ACE2; and the corresponding order for ligand‐6LU7 systems is D2‐6LU7> D4‐6LU7> D3‐6LU7> D5‐6LU7> D1‐6LU7. Galidesivir is predicted as the most effective inhibitor towards both targeted protein structures (DSaverage‐13.1 kcal.mol‐1) and the most bio‐compatible molecule (Mass 264.9 amu; LogP ‐0.9; Polarisability 26.8 Å3). The theoretical screening suggests all drugs, especially Galidesivir (D3), promising for treatment of SARS‐CoV‐2 infection and encourages in‐related clinical trials.

Sulfonylureas derivatives were demonstrated to be effective inhibitors towards α‐glucosidase, thus also expected possessing inhibitory potentiality towards tyrosine phosphatase structure 1B. Five new sulfonylureas derivatives (S1‐S5), exhibiting α‐glucosidase inhibition activity, were selected for in silicoscreening for inhibitability towards UniProtKB‐PTP1B structure. Density functional theory confirms their existence; natural bond orbital analysis infers their stability; electronic transferability suggests their capability regarding intermolecular interaction. Docking‐based investigation interprets the inhibitory potentiality of the compounds into the order of complexes: S3‐PTP1B> S4‐PTP1B> S1‐PTP1B> S5‐PTP1B> S2‐PTP1B. QSARS‐based analysis specifies S4as the most physicochemically and pharmaceutically compatible candidate for the general application as a protein inhibitor (Molecular mass: 213.9 amu; Dispersion coefficient: LogP 4.01; DSaverage: 11.9 kcal.mol‐1). The computer‐based findings encourage further confirmation from experiment‐based researches and development for a versatile inhibitor towards diabetes‐related protein structures (aka. α‐glucosidase and tyrosine phosphatase structure 1B).

From the leaves and barks of Dolichandrone spathaceacollected in the mangrove forest of Hue province, three iridoids {6‐O‐[(E)‐4‐methoxy cinnamoyl]catalpol (1), 6‐O‐[(E)‐3,4‐dimethoxy cinnamoyl]catalpol (2), nemoroside (3)} and three ursane‐type triterpenoids [ursolic acid (4), pomolic acid (5), uncaric acid (6)] were isolated and structurally elucidated. Besides, succrose octaacetate (7), daucosterol tetraacetate (8) and 1‐hentriacontanol (9) were identified from the fruits of this mangrove species. It is the first time compounds 6, 7, 9were isolated from Dolichandrone spathacea. The main constituents of this plant, iridoids 1and 2, were tested for the inhibition of IL‐6, TNF‐α factors and NO production. The anti‐inflammatory activity as well as the phytochemistry of the fruits of this species are reported for the first time.

Piper nigrumL. (black pepper) is highly susceptible to many infectious diseases, especially foot rot caused by Phytophthora capsici andyellow disease caused by Fusarium sporotrichioides. The inhibitability of silver‐carbene Ag‐NHCand di‐silver‐carbene Di‐Ag‐NHCcomplexes on protein 6KD3 in Phytophthora capsiciand protein 1JFA in Fusarium sporotrichioideswas theoretically investigated using molecular docking simulation. The results reveal that both Ag‐NHCand Di‐Ag‐NHCperforming strong inhibitory effects towards both proteins. Docking score energy values regarding [Ag‐NHC]‐6KD3and [Di‐Ag‐NHC]‐6KD3are ‐11.2 and ‐11.7 kcal.mol‐1. The corresponding figures for [Ag‐NHC]‐1JFAand [Di‐Ag‐NHC]‐1JFAare ‐11.1 and ‐13.4 kcal.mol‐1. Also, analysis on hydrogen bonding, interaction distance, and van der Waals interactions formed in the inhibitory systems indicates good site‐site binding between amino acids of the targeted proteins and the carbene molecules. This study introduces Ag‐NHCand Di‐Ag‐NHCcomplexes as potential candidates for prevention of infection caused by Phytophthora capsiciand Fusarium sporotrichioides, thus mitigate the impacts on the production of black pepper.

Surface‐enhanced Raman spectroscopy (SERS), a surface‐sensitive technique, allows the practicability of detecting chemical compounds in ultra‐low concentration. In this work, a chemical enhancement mechanism of SER process of Thiram pesticide adsorbed on copper nanomaterial surface was proposed based on density functional theory (DFT) approaches. Structural and electronic properties of Thiram and Thiram‐Cu20complexes were optimized using PBE method with LanL2DZ basis set for copper atoms and cc‐pVDZ basis set for the non‐metal atoms. In the most stable adsorption configuration, Thiram interacted with Cu20cluster viatwo S(sp2)atoms. The main peaks on normal Raman spectrum of Thiram were characterized at 371, 576, 1414 and 1456 cm‐1responsible for the stretching vibrations of C–S, C=S, S–C–S and C–N groups, respectively. Otherwise, the main peaks of Thiram‐Cu20SERS spectrum were found at 534, 874, 982, 1398 and 1526 cm‐1corresponding to the stretching vibrations of S–S, C‐S, S–C–S, C–N and CH3–N bonds, respectively. The SERS chemical enhancement of Thiram by Cu20cluster was about 2 and 6 times stronger than those obtained from Ag20and Au20cluster, respectively. The chemical enhancement mechanism was also explained by analyzing HOMO and LUMO energies gap and density of states.

In this study, we developed the hybrid QSAR models (HQSAR) for a set of benzamide derivatives by combining genetic algorithms with multivariate regression and support vector machine learning techniques. The genetic algorithm has assisted the selecting process of 2D and 3D molecular descriptors to get a globally optimal HQSARGA‐MLRmodel with k= 7. The hybrid support vector regression model (HQSARGA‐SVR) received from the selected descriptors of the multivariable regression model (HQSARGA‐MLR) has been operated to predict the pIC50activity of validation and prediction groups with MARE% of 0.8492 % and 2.8411 %. The hybrid support vector technique has improved the efficiency of the predictability of the multivariate regression model. The predicted activities pIC50of benzamide derivatives resulting from the HQSARGA‐SVRmodel are reliable enough and in good agreement with experimental data.

The structure and bonding of complexes containing subvalent group‐14 elements [E(PPh3)2→ SiH2]2+(Si‐EP) with E = C to Pb have been researched using charge‐ and EDA‐NOCV methods. The optimized equilibrium geometries for complexes have the most stable structure which has been found for carbone ligand CPas the nearly end‐on bonded form in Si‐CP. In contrast to this, the heavier ligands SiPto PbPin the heavier complexes Si‐SiPto Si‐PbPexhibit strongly side‐on manners. Bond dissociation energies, ‐De(kcal.mol‐1), increase from Si‐CPto the stronger bonded complexes Si‐SiPto Si‐PbP. EDA‐NOCV calculations revealed that the donation [E(PPh3)2→ SiH2]2+displays the significant σ‐interactions of the ligands while the π‐electron sharing exhibits the charges transfer between E(PPh3)2and SiH22+. Bonding analysis indicated that the Si‐E bond results from the decrease in the donation [E(PPh3)2→ SiH2]2+and electrostatic attraction. The investigated complexes possessed E(PPh3)2→ SiH22+strong σ‐donors and E(PPh3)2↔ SiH22+π‐π electrons shared between the two fragments.

Six stable geometrical structures of the interaction between CH3CHS and H2O were observed on potential energy surface at the MP2/ aug‐cc‐pVDZ level of theory. Interaction energies corrected by both ZPE and BSSE for all the complexes at the MP2/aug‐cc‐pVTZ//MP2/aug‐cc‐pVDZ high level of theory range from ‐12.0 to ‐61.4 kJ.mol‐1. When adding water molecule to CH3CHS, stability of interacting system and cooperative capacity of complexes are increased. In general, the strength of complexes is contributed by O–H∙∙∙O/S and C–H∙∙∙O hydrogen bonds, and their stability decreases in the order of O–H∙∙∙O > O–H∙∙∙S > C–H∙∙∙O. Interestingly, a larger contraction and a stronger increase of stretching frequency of Csp2–H bond as compared to Csp3–H bond are observed following complexation although the Csp2–H∙∙∙O H‐bonds are stronger than the Csp3–H∙∙∙O counterparts. This detective result is mainly determined by a decrease in the electron density of the σ*(C − H) orbital.