ItemTowards the Synthesis of Neuroprotective Dictyoquinazol Derivatives(Kalamazoo College, 2023-03-01) Ankley, SamuelThe need for more efficacious neuroprotective pharmacophores has been in high demand during recent years with 795,000 people suffering from strokes every year in the United States alone. Dictyoquinazols may help lead to the answer of this demand as they have proven neuroprotective capabilities as seen in recent studies. These studies, however, are rather limited thus making this an area of research that needs to be looked into on a greater scale. This study looks deeper into the synthesis of Dictyoquinazol derivatives in an attempt to produce new neuroprotective compounds by working towards the synthesis of 2,6, and 4′ substituents. The reduction reactions of nitro benzaldehydes have also proven effective with yields upwards of 64%. The initial synthesis of quinazolinone derivatives has proven effective and leads to decently high yields with both phenyl (42-74%) as well as methyl (76-100%) substituents on carbon 6. Further synthetic analysis has proven difficult while attempting to convert the oxazinone moiety to that of a pyrimidinone while not only ensuring this substitution occurs but also verifying the recyclization of the pyrimidinone. ItemYersinia pestis Adhesins’ Role in Yop Delivery to Neutrophils and Bacterial Survival Using the Neutrophil-like Cell Line HL-60(Kalamazoo College, 2022-11-01) Thakur, AbhishekYersinia pestis is a gram-negative, bacillus bacteria that is the causative agent of the bubonic plague. This strain of Yersinia has been responsible for killing millions of people in history, most notably during the Justinian plague where 25% of the European population was killed. The deadly nature of Y. pestis can be traced to the mechanisms it utilizes. Y. pestis uses a type 3 secretion system (T3SS) to confer cytotoxicity by delivering Yersinia outer proteins (YOPs) to host cells via its needle-like apparatus. In addition to YOPs, Yersinia Pestis has adhesins that attach on the outer membrane and help in docking onto the host cell. The goal of this study was to understand the role of adhesins in the delivery of YOPs to a neutrophil-like cell line HL-60s. The adhesins of interest include Adhesion and Invasin locus (Ail), Plasminogen activator (Pla), and pH-6 antigen (PsaA). This study utilized fluorescence microscopy as well as image cytometry to analyze the effect these adhesins had on YOP delivery. The experiments conducted in this study showed that the adhesins had a positive effect on YOP delivery while having a diminished effect in the presence of serum. Results from this study and previous studies done on the role of adhesins in YOP delivery serve as basis for future studies regarding genetic manipulation and determining critical pathways that can provide clues on how to control Yersinia Pestis. ItemExploring a Sponge-Derived Leucobacter sp. as a Potential Source for Antibiotics(Kalamazoo College, 2023-01-01) Thakali, SujaAntibiotic resistance is a rising global health concern. Many of the current antibiotics produced by microorganisms are derived from well researched bacteria such as the genus Streptomyces. Though Streptomyces is a remarkable source of potential therapeutics and should be continued to be studied, studying predominantly this genus limits the diversity of chemical structures and scaffolds to be discovered. This urges a call to diversify the bacteria currently being studied to produce or inspire novel natural product scaffolds. In the current study, we isolated a Leucobacter sp. from a freshwater sponge in the Apostle Islands which was grown on a large scale and the secondary metabolites were extracted for compound isolation and characterization. As an understudied bacterial genus, which it is characterized as a genus with fewer than five papers that report a secondary metabolite, Leucobacter sp. has the potential to offer unique chemical scaffolds. Utilizing spectrometric techniques, we were able to dereplicate the secondary metabolites extracted using the DEREPLICATOR tool available on GNPS, which indicating no known antibiotics present. This suggests that there could be new antibacterial secondary metabolites that have not previously been discovered or studied. Analyzed LC/MS q-TOF data shows a molecule with the MW of 1268 m/z. HPLC and NMR spectroscopy experiments are currently in progress to isolate and characterize this compound and others present in the extract. We hope to obtain bioactivity data once isolation and characterizitaion is accomplished. This study into the Leucobacter isolate could exhibit new chemical spaces and broaden our knowledge of secondary metabolites and novel scaffolds derived from the Leucobacter sp. that can be used in the fight against antibiotic resistance. ItemSynthesis of Plasmenyl PC and PE Polar Lipids(Kalamazoo College, 2023-03-01) Rawlings, AbbyPlasmalogens are a type of polar lipid that are found naturally throughout the human body. These compounds are categorized as plasmalogens by a vinyl ether bond and an ester linked fatty acid chain. The plasmalogens in this study consist of the arachidonic, docosahexaenoic, and adrenic acid substituted species. Recent research has linked these plasmalogens to degenerative diseases which opens up their potential as biomarkers and new theraputics. This research synthesized each of these compounds in their glycerophosphoryl-ethanolamine (PE) and glycerophosphoryl-choline (PC) forms. Areas of this synthesis were explored, focusing on optimizing steps, success in the PC to PE conversion, and creating new plasmalogens. The PC to PE conversion step is notable because it uses an enzymatic reaction, transphosphatidylation, with phospholipase-D to cleave at the choline head and turn it into an ethanolamine head. This step was a concern with the low stability of the vinyl ether bond. This research proves this to be a promising method for the creation of these compounds. ItemMethods for the Separation of Acylated Surfactant Precursors from Fatty Acids(Kalamazoo College, 2023-03-01) Otgonjargal, GunzayaA widely used commercial surfactant, linear alkyl-benzene sulfonate surfactant (LAS), is produced from fossil fuel molecules and requires the incorporation of chelating agents such as metal chelants, increasing complexity and cost. Bio-renewable and biomass-derived oleo-furan surfactants allow replacing current commercial surfactants. One of the major precursors for oleofuran surfactants is alkyl furan ketone (AFK), which is produced from the indirect acylation of anhydride and furanic substrate. Post-indirect acylation products of AFK and fatty acid (FA) byproducts form a eutectic homogenous mixture due to their similar physical properties. Multiple steps of cooling crystallization using 75 wt% methanol as a solvent is the current purification method for Sironix. This is not an ideal separation method due to its succession of steps and poor atom efficiency resulting environmentally unfriendly approach. There are many proposed ways of separating eutectic-forming mixtures such as controlling the nucleation and seeding the crystal, but an efficient, simple and eco-friendly separating approach is still in search for the industry-scale mixtures. Therefore, a better separating method for AFK and FA is needed. In this project, different methods to purify oleofuran surfactant precursor, alkyl furan ketone has experimented with using the information of binary-phase diagrams and Differential Scanning Calorimetry experiments. As a result of this project, a combination of esterification of fatty acid with cooling crystallization was proposed as a possible better separation method.