A novel method for preparing Eligulstat through chiral resolution.

Eliglustat is a ceramide glucosyltransferase inhibitor work as first line oral therapy for adults with Gaucher disease type 1 (a rare disease) at present. Although the eliglustat in enantiomerically pure forms is obtained by asymmetric syntheses, the reported methods suffer from many limits when it comes to industrial applications. Therefore, the preparation of a racemic mixture followed by resolution can still be a viable and straightforward alternative, especially when it could be adapted to large scale. Herein, we developed an effective and practical synthetic route to prepare stereoisomers mixture of eliglustat, and a novel chiral resolution method to prepare eliglustat. Using 1,1'-Binaphthyl-2,2'-diyl -hydrogenphosphate (BNDHP) as resolution reagent, optical pure eliglustat (e.e. >99%, 13.97% total yield) could be obtained after recrystallization.

Ag/Pyridine Co-Mediated Oxidative Arylthiocyanation of Activated Alkenes.

An efficient Ag/pyridine co-mediated oxidative arylthiocyanation of activated alkenes via radical addition/cyclization cascade process was developed. This reaction could be carried out under mild conditions to provide biologically interesting 3-alkylthiocyanato-2-oxindoles in good to excellent yields. Mechanistic studies suggested a unique NCS• radical addition path and clarified the dual roles of catalytic pyridine as base and crucial ligand to accelerate the oxidation of Ag(I) to Ag(II), which is likely oxidant responsible for the formation of NCS• radical. These mechanistic results may impact the design and refinement of other radical based reactions proceeding through catalytic oxidations mediated by Ag(I)-pyridine/persulfate. The chemical versatility of thiocyanate moiety was also highlighted via SCN-tailoring chemistry in post-synthetic transformation for new S-C(sp³/sp²/sp), S-P, and S-S bonds constructions. The protocol provides an easy access to many important bioisosteres in medicinal chemistry and an array of sulfur-containing 2-oxindoles that are difficult to prepare by other approaches.

Investigation on Microstructure of Beetle Elytra and Energy Absorption Properties of Bio-Inspired Honeycomb Thin-Walled Structure under Axial Dynamic Crushing.

The beetle elytra requires not only to be lightweight to make a beetle fly easily, but also to protect its body and hind-wing from outside damage. The honeycomb sandwich structure in the beetle elytra make it meet the above requirements. In the present work, the microstructures of beetle elytra, including biology layers and thin-walled honeycombs, are observed by scanning electron microscope and discussed. A new bionic honeycomb structure (BHS) with a different hierarchy order of filling cellular structure is established. inspired by elytra internal structure. Then the energy absorbed ability of different bionic models with the different filling cell size are compared by using nonlinear finite element software LS-DYNA (Livermore Software Technology Corp., Livermore, CA, USA). Numerical results show that the absorbed energy of bionic honeycomb structures is increased obviously with the increase of the filling cell size. The findings indicate that the bionic honeycomb structure with second order has an obviously improvement over conventional structures filled with honeycombs and shows great potential for novel clean energy absorption equipment.

Energy absorption characteristics of bio-inspired honeycomb column thin-walled structure under impact loading.

Beetles have developed the elytra that are interesting and impressive strategy for thriving in their native environments. The elytra, although formed from simple biopolymer constituents, take on many effective designs. In present work, internal structure of elytra is discussed and three bionic structures named as the bio-inspired honeycomb column thin-walled structure (BHTS) are proposed. Then the crushing behavior and energy absorption characteristics of the BHTS under axial impact loading are investigated by numerical simulation. This study reveals not only the relationship between the adding mode and energy absorption characteristics, but also the influence of column diameter on the BHTS. The findings show that the BHTS represents a significant improvement over honeycomb structures and show potential applications in the field of protective equipment.

Effects of micro-structure on aerodynamics of Coccinella septempunctata elytra (ladybird) in forward flight as assessed via electron microscopy.

The effects of micro-structure on aerodynamics of Coccinella septempunctata (Coleoptera: Coccinellidae) elytra in forward flight were investigated. The micro-structure was examined by a scanning electron microscope and a digital microscope. Based on the experimental results, five elytron models were constructed to separately investigate the effects of the camber and the local corrugation in both leading edge and trailing edge on aerodynamics. Computational fluid dynamic simulations of five elytron models were conducted by solving the Reynolds-Averaged Navier-Stokes equations with the Reynolds number of 245. The results show that camber and the local corrugation in the leading edge play significant roles in improving the aerodynamic performance, while the local corrugation in the trailing edge has little effect on aerodynamics.

Functional morphology and structural characteristics of wings of the ladybird beetle, Coccinella septempunctata (L.).

In recent years, the surface morphology and microstructure of ladybird (Coccinella septempunctata) wings have been used to help design the flapping-wing micro air vehicle (FWMAV). In this study, scanning electron microscopy (SEM) was used to verify the functional roles of the ladybird forewing and hindwing. Surface morphology and the cross-sectional microstructure of the wings are presented. Detailed morphology of ladybird forewings was observed using atomic force microscopy (AFM) and the composition of the wings was characterized using Fourier transformed infrared spectroscopy (FTIR). The ladybird forewing may possess different performance characteristics than the beetle, Allomyrina dichotoma. Additionally, the circular holes in the forewing might be important for decreasing the weight of the forewing and to satisfy requirements of mechanical behavior. Microsc. Res. Tech. 79:550-556, 2016. © 2016 Wiley Periodicals, Inc.