received: )Clarifying electronic and vibronic properties at individual molecule level provides key insights to future chemistry, nanoelectronics, and quantum information technologies. The single electron tunneling spectroscopy 1-4 has been used to study the charging/discharging process in single molecules. The obtained information was, however, mainly on static electronic properties, and access to their dynamical properties was very indirect. Here, we report on the terahertz (THz) spectroscopy of single fullerene molecules by using a single molecule transistor (SMT) geometry.From the time-domain THz autocorrelation measurements, we have obtained THz spectra associated with the THz-induced center-of-mass oscillation of the molecules. The observed peaks are finely split into two, reflecting the difference in the van der Waals potential profile experienced by the molecule on the metal surface when the number of electrons on the molecule fluctuates by one during the single electron tunneling process.Such an ultrahigh-sensitivity to the electronic/vibronic structures of a single molecule upon adding/removing a single electron has been

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Succinate dehydrogenase (SDH) is one of the most important molecular targets for the development of new fungicides. Carboxamide fungicides are a class of SDH inhibitors widely used to inhibit highly destructive plant pathogens. Although cases of resistance have been found in fungal pathogens due to the unrestricted use in recent years, there is still demand for new compounds with improved fungicidal activity. Therefore, a series of ester compounds were designed to investigate potential novel antifungal molecules. First, the antifungal activity of different benzyl alcohol compounds (A1–A21) was tested, and a highly active fragment (3,5-dichlorobenzyl alcohol) was found. Subsequently, various compounds were synthesized by esterification between different acids and 3,5-dichlorobenzyl alcohol, among which compound 5 exhibited remarkable antifungal activity against Botrytis cinerea and Rhizoctonia solani with EC50 values of 6.60 and 1.61 mg/L, respectively, which were comparable to those of commercial fungicide boscalid (EC50 = 1.24 and 1.01 mg/L). In vivo testing further demonstrated that compound 5 was effective in suppressing B. cinerea (200 mg/L, 50.9%). Moreover, SDH inhibition assays, fluorescence quenching analysis, and determination of mitochondrial membrane potential revealed that compound 5 has similar effects to boscalid. Furthermore, the fungicidal activity of target compounds can be maintained by modifying the amide bond to an ester bond. These results will provide basis for the development of novel fungicides.

Odorant-binding proteins (OBPs) play an important role as ligand-transfer filters in olfactory recognition in insects. (E)-β-farnesene (EBF) is the main component of the aphid alarm pheromone and could keep aphids away from crops to prevent damage. Computational insight into the molecular binding mode of EBF analogs containing a heterocycle based on the structure of Megoura viciae OBP 3 (MvicOBP3) was obtained by molecular docking and molecular dynamics simulations. The results showed that high affinity EBF analogs substituted with an aromatic ring present a unique binding conformation in the surface cavity of MvicOBP3. A long EBF chain was located inside the cavity and was surrounded by many hydrophobic residues, while the substituted aromatic ring was exposed to the outside due to limitations from the formation of multiple hydrogen bonds. However, the low activity EBF analogs displayed an exactly inverted binding pose, with EBF loaded on the external side of the protein cavity. The affinity of the recently synthesized EBF analogs containing a triazine ring was evaluated in silico based on the binding modes described above and in vitro through fluorescence competitive binding assay reported later. Compound N1 not only showed a similar binding conformation to that of the high affinity analogs but was also found to have a much higher docking score and binding affinity than the other analogs. In addition, the docking score results correlated well with the predicted logP values for these EBF analogs, suggesting highly hydrophobic interactions between the protein and ligand. These studies provide an in silico screening model for the binding affinity of EBF analogs in order to guide their rational design based on aphid OBPs.

Superatoms have been regarded as new building blocks for artificially synthesized electronic and magnetic materials and have been attracting great attention in nano-assembly and cluster science. 1,2 Upon the discovery of the superatom states in fullerene 3 and its derivatives 4 , particularly, endohedral metallofullerenes 5-7 (a positively charged core metal atom is surrounded by a negatively charged carbon cage), the superatom properties have become more attractive, because ultrafast motion of the trapped atom modifies the electron density distribution in a local area of a picometer-scale 8 . So far, the encapsulated atom position was imaged by scanning tunneling microscopy 9 (STM) or transmission electron microscopy 10 (TEM). However, they can image the encapsulated metal atom only in a time-averaged manner; the observation of ultrafast atom motion is very challenging because dynamical processes take place in the terahertz (THz) frequency range 11,12 in a picometer-scale. In the present work, a C82 fullerene molecule that encapsulates a Ce atom is placed in a sub-nm gap of metal electrodes and excited by THz radiation to investigate the ultrafast dynamics of the Ce atom. We have observed two THz-induced photocurrent peaks associated with the bending and stretching motions of the encapsulated Ce atom. Furthermore, by measuring the bias voltage dependence of the THz-induced photocurrent, we have found that the THz-induced photocurrent flows not only by the photoconductive effect but also by the