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This paper describes the syntheses, crystallization, characterization and energetic properties (calorimetry) of closo-dodecahydroborate salts with guanidinium and aminotetrazolium based cations. The salts were readily produced in good yields by metathesis (ion exchange) reactions depending on the water solubility of the dodecahydroborate salts. Water insoluble salts can be synthesized from the potassium or sodium salts by a simple metathesis reaction with the corresponding halide of the desired organic cation. Water soluble salts can be prepared via two consecutive metathesis reactions: the halide is first converted to the corresponding sulfate, which is reacted in turn with barium dodecahydroborate, yielding the water soluble organic closo(B12H12)2− salt and the insoluble BaSO4. The product salt is conveniently isolated by water evaporation. The aminotetrazolium salt 12d gives nice crystals when recrystallized from DMF and NMP but incorporate solvent. Guanidinium salt 15a recrystallizes from nicely from water as a monohydrate. Thermogravimetric analyses established the thermal stabilities of these compounds. The enthalpies of combustion of representative salts were determined using a constant volume bomb calorimetry. The data shows that these salts possess relatively high heats of combustion (ΔUc, ca. 35 kJ·g−1), and have the potential to serve as green high-energy materials.

Similarly to other transition metal sulfides, nickel sulfide nanocrystals can be potentially used for functional device applications. However, controlling morphology and stoichiometry to target specific applications is a synthesis challenge. In this work we developed a rapid, one-step, chemical vapor deposition synthesis of nickel sulfide dendritic nanostructures with fractal geometry. Microtome-EDS compositional analysis of the mature crystal indicates a trend of decreasing sulfur and increasing nickel concentration towards the tip of the mature crystals. Following thorough investigation of these nanocrystals at different stages of their nucleation and growth by means of XRD, HR-SEM, HR-TEM, and Raman spectroscopy, we suggest possible kinetic mechanisms for the crystal formation and development. This work contributes to the understanding of growth mechanisms of dendritic structures with complex morphology.

TLR4, a member of the Toll-like receptor (TLR) family, serves as a pattern recognition receptor in the innate immune response to microbial pathogens. TLR4 also regulates the inflammatory reaction to ischemic injury in the heart. The TRIF-related adaptor molecule (TRAM) is an adapter that recruits the Toll/interleukin 1 receptor (TIR) domain, which contains adapter-inducing IFN-β (TRIF), to activate TLR4, following TRIF-dependent cytokine gene transcription. On the basis of a known TRAM-derived decoy peptide, 10 of its peptidomimetics were synthesized. One of them, 1-benzyl-5-methyl-4-( n-octylamino)pyrimidin-2(1 H)-one (21), exhibited high potency and efficacy in vitro. In vitro results and in silico analysis provided evidence for the possible direct interaction of 21 with the TLR4 complex. Administered in mice, 21 was able to block the pathophysiological manifestation of MI, restoring the concomitant tissue damage, with a 100% survival rate. Thus, inhibition of TLR4-mediated inflammation in postischemic myocardium could be used as an approach for developing cardioprotective drugs.