Gradient Microstructure Design in Stainless Steel: A Strategy for Uniting Strength-Ductility Synergy and Corrosion Resistance.

Martensite transformation and grain refinement can make austenitic stainless steel stronger, but this comes at a dramatic loss of both ductility and corrosion resistance. Here we report a novel gradient structure in 301 stainless steel sheets, which enables an unprecedented combination of high strength, improved ductility and good corrosion resistance. After producing inter-layer microstructure gradient by surface mechanical attrition treatment, the sheet was annealed at high temperature for a short duration, during which partial reverse transformation occurred to form recrystallized austenitic nano-grains in the surface layer, i.e., introducing extra intra-layer heterogeneity. Such 3D microstructure heterogeneity activates inter-layer and inter-phase interactions during deformation, thereby producing back stress for high yield strength and hetero-deformation induced (HDI) hardening for high ductility. Importantly, the recrystallized austenitic nano-grains significantly ameliorates the corrosion resistance. These findings suggest an effective route for evading the strength-ductility and strength-corrosion tradeoffs in stainless steels simultaneously.

Discovery of phenylpiperazine derivatives as IGF-1R inhibitor with potent antiproliferative properties in vitro.

A series of phenylpiperazine derivatives (3a-3q) were designed and synthesized. In vitro assays indicated that several phenylpiperazine derivatives had excellent antiproliferative properties against four cancer cell lines including multidrug-resistant cancer cell lines, with IC50 values in the low micromolar range. The average IC50 of the most active compound 3b is 0.024µM to the MCF-7 cell line. In addition, the mechanism of action of these new analogues was investigated by molecular docking studies, insulin-like growth factor 1-receptor (IGF-1R) kinase assay and apoptosis induced assay. These studies confirmed that these new phenylpiperazine derivatives maintain their mechanisms of action by disrupting IGF-1R kinase.

Aromatic diacylhydrazine derivatives as a new class of polo-like kinase 1 (PLK1) inhibitors.

A novel class of aromatic diacylhydrazine derivatives was designed as PLK1 inhibitors. All the 19 new synthesized compounds were assayed for antitumor activity against the respective cervical cancer cells. In which, nine compounds with better antitumor activities were further tested for their PLK1 inhibitory activity. Last, we have successfully found that compound 7k showed both the promising antitumor activity with IC50 of 0.17 µM against the cervical cancer cells, and also processed the most potent PLK1 inhibitory activity with IC50 of 0.03 µM. In addition, docking simulation also carried out in this study to give a potent prediction binding mode between the small molecule and PKL1 (PDB code: 1umw) protein.

Synthesis and antitumor activity of 1,3,4-oxadiazole possessing 1,4-benzodioxan moiety as a novel class of potent methionine aminopeptidase type II inhibitors.

A series of 1,3,4-oxadiazole derivatives containing 1,4-benzodioxan moiety (7a-7q) have been designed, synthesized and evaluated for their antitumor activity. Most of the synthesized compounds were proved to have potent antitumor activity and low toxicity. Among them, compound 7a showed the most potent biological activity against Human Umbilical Vein Endothelial cells, which was comparable to the positive control. The results of apoptosis and flow cytometry (FCM) demonstrated that compound 7a induce cell apoptosis by the inhibition of MetAP2 pathway. Molecular docking was performed to position compound 7a into MetAP2 binding site in order to explore the potential target.