Synthesis of fluconazole analogues with focusing on resistant strains Candida
Fungal infections, particularly those caused by resistant strains like Candida auris and Candida glabrata, pose a significant threat to global health. The widespread use of azole antifungals, such as fluconazole, has driven the emergence of multidrug-resistant strains, undermining the efficacy of existing treatments. These challenges necessitate the development of novel antifungal agents with enhanced activity and reduced resistance profiles. To address resistance mechanisms, we designed and synthesized hybrid molecules combining triazole and thiazolidine-2,4-dione (TZD) pharmacophores. This strategy leverages dual mechanisms of action: inhibiting fungal CYP51, a key enzyme in ergosterol biosynthesis, and disrupting fungal cell wall integrity. The structural versatility of hybrid molecules allows for targeted modifications to enhance antifungal potency, binding specificity, and pharmacokinetics. Using a stepwise synthetic approach, triazole-containing piperazine derivatives were first prepared and coupled with TZD-based carboxylic acids via optimized condensation reactions. The structures of the synthesized compounds were confirmed through advanced spectroscopic methods, including 1D/2D NMR and high-resolution mass spectrometry. The antifungal activity of these hybrids was evaluated in vitro against clinical and reference strains of Candida spp. and Aspergillus fumigatus. Among the synthesized compounds, 6a demonstrated notable activity against Candida parapsilosis (MIC 0.06 μg/mL), comparable to voriconazole. Compound 4b exhibited moderate activity against C. parapsilosis (MIC 1–2 μg/mL) and A. fumigatus (MIC 8 μg/mL). However, most compounds showed limited efficacy against highly resistant strains such as C. albicans 8R and C. krusei. This study highlights the potential of hybrid triazole-TZD molecules in overcoming resistance and improving antifungal efficacy. While promising, further optimization is required to broaden the spectrum of activity and enhance efficacy against multidrug-resistant pathogens. These findings contribute to the growing field of antifungal drug development, emphasizing hybrid approaches as a viable solution for combating fungal resistance.
Glass Coloring by the production of Colloidal Hydroxide
When doing an experiment to produce colloidal ferric hydroxide, the bottom of the beaker used was colored in yellow-brown with thin film interference. This phenomenon is well-known, but the cause has not been clearly studied. As a result of the research, the coloration on the bottom of the beaker is caused by β-FeOOH forming a thin film which is chemically bonded with Si-OH on the glass surface. Also, the amount of β-FeOOH depends on the number of experiments, the area of the bottom of the beaker, and the concentration of FeCl3 aq. We found that it can be possible to determine the amount of β-FeOOH from the formula m=knsc and the adhesion constant was found to be 6.8✕10-3 (L/m2). In addition, from machine learning we predicted that the thin film thickness becomes thicker as it moves away from the center.
Application of Carbon Aerogels in Lithium-Air Batteries
One of the main challenges with today’s batteries is their relatively low volumetric and specific capacities. The highest specific capacity can be achieved with lithium-air batteries, which use metallic lithium as the anode and typically some form of porous carbon as the cathode. To enhance performance, aerogels—among the world’s lightest solid materials—are ideal candidates for cathodes. Resorcinol-formaldehyde (RF)-based carbon aerogels, for example, serve this purpose well. In my work, I utilized two types of carbon aerogels as cathode materials: one derived from pyrolyzed resorcinol-formaldehyde polymer and the other a graphene-oxide-modified version of this carbon gel. I integrated the carbon aerogels I had pyrolyzed into lithium-air batteries to improve the cell’s performance, energy density, and capacity compared to cells using activated carbon. In my research, I examined the pore structure and surface properties of these materials in aqueous media using NMR (nuclear magnetic resonance) relaxometry and cryoporometry, exploring their impact on battery efficiency. I found that the graphene-oxide-containing sample's pores filled with water in a layered manner, indicating a more hydrophilic surface, which suggests a denser arrangement of oxygen-containing functional groups compared to the unmodified carbon aerogel. The pore sizes were reduced after adding graphene oxide, resulting in an increased specific surface area for the sample. Incorporating the reduced graphene-oxide-containing carbon aerogel enabled the creation of a more efficient, higher-capacity battery than with the RF carbon aerogel. This improved performance is likely due to the aerogel’s higher oxygen content and altered morphology. The increased oxygen content provides more active sites for oxygen reduction, meaning that a greater specific power output can be obtained from the battery.