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Bacterial strains that produce New Delhi metal-β-lactamase 1 (NDM-1) are a worldwide health threat. It remains a challenging task to find a potent NDM-1 inhibitor for clinical practice.Molecular docking and virtual screening of an in-house fungal natural product database for NDM-1 inhibitors were performed. Based on the screening results, the affinity and inhibition ability of potential NDM-1 inhibitors were determined using purified NDM-1. The efficacy of compounds in combination with four β-lactam antibiotics (meropenem, imipenem, ceftriaxone and ampicillin) was evaluated. Morphological changes in Klebsiella pneumoniae ATCC BAA-2146 after treatment with the compounds were visualised by transmission electron microscopy.In silico screening led to the identification of four fungal products as potential NDM-1 inhibitors. Emerione A (1), a methylated polyketide with bicyclo[4.2.0]octene and 3,6-dioxabicyclo[3.1.0]hexane functionalities, has significant activity in cells (KConsidering the low toxicity of emerione A (1), it may represent a potential lead compound for anti-NDM-1 drug development.

Septedine (2) is a hetidine type C20-diterpenoid alkaloid bearing an oxygenated heptacyclic scaffold. We have accomplished the first and asymmetric total synthesis of 2 and its 7-deoxy analogue 3. A functionalized tricyclic intermediate was prepared with excellent enantiopurity by using Carreira polyene cyclization. An unusual anionic Diels–Alder reaction was responsible for the construction of the bicyclo[2.2.2]octane. The α-methyl ketone was furnished by iridium-catalyzed allylic alcohol isomerization. Sanford Csp3–H oxidation was exploited to install the secondary hydroxy group of 2. The oxazolidinopiperidine was assembled by selective reductive amination and spontaneous N,O-ketalization at a final stage.

We have accomplished the asymmetric total synthesis of arcutinidine, arcutinine, and arcutine, three arcutine-type C20-diterpenoid alkaloids. A pentacyclic intermediate was rapidly assembled by using two Diels-Alder reactions. We developed a cascade sequence of Prins cyclization and Wagner-Meerwein rearrangement to construct the core of arcutinidine, which was then elaborated into an oxygenated pentacycle through a scalable route. Chemoselective reductive amination followed by spontaneous imine formation furnished the pyrroline motif in the final stage. We clarified the S configuration of the α-carbon of the acyl group within arcutine through chemical synthesis and crystallographic analysis.

We have accomplished the asymmetric total synthesis of arcutinidine and arcutinine, two arcutine-type C20-diterpenoid alkaloids. A pentacyclic intermediate was rapidly assembled by using two Diels−Alder reactions. A cascade sequence of Prins cyclization and Wagner−Meerwein rearrangement was then developed to construct the core of arcutinidine, which was further elaborated into an oxygenated pentacycle through a scalable route. Chemoselective reductive amination followed by spontaneous imine formation furnished the pyrroline motif at a final stage.

2020 is the last year of the 13th Five-Year Plan, and also the final year of building a well-off society in an all-round way. During the 13th Five-Year Plan, small and medium-sized rivers in this province have experienced large-scale treatment, playing an essential role in flood control and drainage, agricultural irrigation, disaster prevention and mitigation, and improvement of river ecological environment in addition to improving the currently weak water-conservancy infrastructure. However, local government still have problems in funding, land acquisition, segment-based management and treatment, project maintenance, and the balance between flood control and eco-system. Therefore, it is necessary to take effective measures and give the small and medium-sized rivers a greater role in flood control, drainage and eco-system apart from increasing investment in these fields.

We constructed a small library of indole terpenoid mimics using a hybridizing strategy to link various indole and α,β-unsaturated enone building blocks together. Prepared compounds were evaluated for the cytotoxicity against a panel of cancer cell lines. An indolyl ketone called JP18 was identified as a cell cycle regulator, and the underlying mechanism was investigated.

The first total synthesis of mycoleptodiscin A, a structurally unusual indolosesquiterpenoid possessing an ortho-benzoquinone motif, has been accomplished. A sulfone alkylation coupled two readily available fragments to give an aryl triene intermediate. The tetracyclic core of the molecule was assembled through a highly enantioselective iridium-catalyzed polyene cyclization. The benzylic homologation was achieved by a cationic cyanation. The indole motif was constructed via a copper-mediated intramolecular C-N bond formation at a late stage.

The chemical synthesis of indole terpenoids of structural and biological interests has attracted remarkable attention. Here we report an Eu(fod)3 -catalyzed indole conjugate addition reaction, which tolerates various acid-sensitive functional groups. A collection of indole terpenoid mimics have been prepared from natural product-derived α,β-unsaturated enones on the basis of this reaction. The further conversion of the indole adducts into more complex natural product-like molecules has also been demonstrated.

The mathematic relationship between the given orientations of two-prism groups and the corresponding pointing position of outgoing beam is the basic prerequisite needed in applications of achromatic risley prisms to steer beam in free space. Based on vectorial law of refraction, this paper finishes the derivation of the analytic formulae of the relationship wanted. Then the test samples obtained by the analytic formulae, the method of paraxial approximation and professional the optical software are compared respectively. The results prove the correctness of the analytic formulae, as well as its necessity and superiority in high-precision pointing solution when beam is steered over wide angular range.

The first total synthesis of mycoleptodiscin A, a structurally unusual indolosesquiterpenoid possessing an ortho-benzoquinone motif, has been accomplished. A sulfone alkylation coupled two readily available fragments to give an aryl triene intermediate. The tetracyclic core of the molecule was assembled through a highly enantioselective iridium-catalyzed polyene cyclization. The benzylic homologation was achieved by a cationic cyanation. The indole motif was constructed via a copper-mediated intramolecular CN bond formation at a late stage.

The first total syntheses of terpenoids taiwaniadducts B (I), C (II) and D (III) are described.

The first total syntheses of taiwaniadducts B, C, and D have been accomplished. Two diterpenoid segments were prepared with high enantiopurity, both through Ir-catalyzed asymmetric polyene cyclization. A sterically demanding intermolecular Diels–Alder reaction promoted by Er(fod)3 assembled the scaffold of taiwaniadducts B and C. A carbonyl-ene cyclization forged the cage motif of taiwaniadduct D at a late stage, providing over 200 mg of this compound.

A divergent approach was developed toward the total synthesis of taiwaniaquinoids. An advanced intermediate 5a with trans A/B ring junction was concisely assembled by employing a Bi(OTf)3-catalyzed cationic cyclization and a Wolff-type ring contraction as key steps. This common intermediate was readily converted to racemic taiwaniaquinones A and F and taiwaniaquinols B and D, respectively.