Efficient Synthesis of Benzothiazinone Analogues with Activity against Intracellular Mycobacterium tuberculosis

8-Nitrobenzothiazinones (BTZs) are a promising class of antimycobacterial agents currently under investigation in clinical trials. Starting from thiourea derivatives, a new synthetic pathway to BTZs was established. It allows the formation of the thiazinone ring system in one synthetic step and is applicable for preparation of a wide variety of BTZ analogues. The synthetic procedure furthermore facilitates the replacement of the sulphur atom in the thiazinone ring system by oxygen or nitrogen to afford the analogous benzoxazinone and quinazolinone systems. 36 BTZ analogues were prepared and tested in luminescence-based assays for in vitro activity against Mycobacterium tuberculosis (Mtb) using the microdilution broth method and a high-throughput macrophage infection assay.     

The Influence of the Various Types of Binder on the burning characteristics of the magnesium-, boron-, and aluminum-based igniters

The behaviour of six different types of binders phenol-formaldehyde resin, shellac, polyvinylchloride, ethylcellulose, nitrocellulose, and fluorel was investigated in pyrotechnic compositions on the basis of magnesium, boron and aluminum. It has been found that the nature of the binder significantly influences the burning characteristics of the igniters. Correlation has been found between binder exothermicity and investigated characteristics. In addition, the influence of the contents of phenol-formaldehyde resin and of fluorel, in the range of 0% to 25% on the same performance characteristics was studied. Phenol-formaldehyde resin has been chosen as preferred binder for the investigated igniters in an amount of 5%.     

Probing the Mysterious Behavior of Tungsten as a Dopant Inside Pristine Cobalt-Free Nickel-Rich Cathode Materials

Nickel-rich cathode materials with small amounts of tungsten (W) dopants have attracted extensive attention in recent years. However, the chemical state, crystalline form, compound chemistry, and location of W in these layered cathodes are still not well-understood. In this study, these missing structural properties are determined through a combination of macro-, to atomic-sensitive characterization techniques and density functional theory (DFT). W-doped LiNiO₂ (LNO) particles, prepared with mechanofusion and coprecipitation methods, are used to probe changes in the structure and location of W-species. The results indicate that W is mainly distributed on the surfaces and inside grain boundaries of the secondary particles, regardless of the doping method. Electron energy loss spectroscopy (EELS) mapping confirms the simultaneous presence of W, O, with and without Ni in the grain boundaries as well as W- and O-rich regions on the very surface. The W-rich areas inside the grain boundaries are found to be in two forms, crystalline and amorphous. This paper suggests the presence of kinetically stabilized-Li_4+xNi_1-xWO₆ (x = 0, 0.1) with the possibility of Li_xW_yO_z phases in LNO which are consistent with the electron microscopy, X-ray absorption and diffraction data. The multiple roles of W in this complex microstructure are discussed considering the W distribution.