Synthesis of 4-Thiazolidinone Small Molecules as Potential Inhibitors of the Arp2/3 Complex

Life-essential cellular processes such as endocytosis, motility, and division rely on a cell’s ability to precisely regulate construction of actin filaments in response to external factors and signals. Intrinsically involved in this process is the Actin Related Protein 2/3 (Arp2/3) Complex, a seven-subunit ATPase that functions by nucleating a daughter branch of actin from the side of a pre-existing microfilament. Active Arp2/3 complex is necessary for the proliferation of certain metastatic cancers, and inhibition of Arp2/3 complex is emerging as a potentially useful treatment strategy for such cancers. We describe synthesis and in vitro assays of 4-thiazolidinones predicted by computational methods to inhibit of Arp2/3 Complex strongly, and therefore serve as potential lead compounds for drug development. Known Arp2/3 inhibitor CK-869 serves as the starting point for derivative synthesis. We discuss the efforts towards the synthesis of new compounds and the biochemical data collected about their potency

Synthesis of Small Molecule Derivatives of CK-666 as Potential Inhibitors of the Arp2/3 Complex

The Actin-Related Protein (Arp) 2/3 Complex is an actin nucleating factor intrinsically involved in cellular regulation of actin networks during life-essential processes such as motility. Overexpression of the Arp2/3 complex has indicated as a factor allowing the proliferation of certain metastatic cancers. This work describes the synthesis and in vitro biochemical testing of several molecules predicted by computational docking to be inhibitors of Arp2/3 Complex, and therefore of potential interest in clinical applications. The molecules are designed based off of the structure of known Arp2/3 inhibitor CK-666, which was discovered via high-throughput screening. Details of the synthesis of the tryptamine derivatives are discussed, and the bulk actin polymerization assay used to determine potency of the new compounds is discussed

\u3cem\u3eIn Vitro\u3c/em\u3e Determination of Potency of Small Molecule Inhibitors of Arp2/3 Complex

Actin is a key protein building block of actin microfilaments, which are constructed and deconstructed in response to cellular signaling pathways to regulate cellular processes such as motility, division, and endocytosis. Arp2/3 Complex is a 7-subunit protein complex that is in involved in cellular construction of branched actin networks, functioning by attaching to the side of a pre-existing actin filament and nucleating a daughter branch. Overexpression of Arp2/3 complex has been linked to the ability of certain metastatic cancers to proliferate. This work describes the synthesis and in vitro biochemical testing of several molecules predicted by computational docking to be inhibitors of Arp2/3 Complex, and therefore of potential interest in clinical applications. A bulk actin polymerization assay is used as the key method to determine the potency of inhibitor candidates. Structure-activity relationships derived from these results are also discussed

Firefly Luciferase and Rluc8 Exhibit Differential Sensitivity to Oxidative Stress in Apoptotic Cells

Over the past decade, firefly Luciferase (fLuc) has been used in a wide range of biological assays, providing insight into gene regulation, protein-protein interactions, cell proliferation, and cell migration. However, it has also been well established that fLuc activity can be highly sensitive to its surrounding environment. In this study, we found that when various cancer cell lines (HeLa, MCF-7, and 293T) stably expressing fLuc were treated with staurosporine (STS), there was a rapid loss in bioluminescence. In contrast, a stable variant of Renilla luciferase (RLuc), RLuc8, exhibited significantly prolonged functionality under the same conditions. To identify the specific underlying mechanism(s) responsible for the disparate sensitivity of RLuc8 and fLuc to cellular stress, we conducted a series of inhibition studies that targeted known intracellular protein degradation/modification pathways associated with cell death. Interestingly, these studies suggested that reactive oxygen species, particularly hydrogen peroxide (H2O2), was responsible for the diminution of fLuc activity. Consistent with these findings, the direct application of H2O2 to HeLa cells also led to a reduction in fLuc bioluminescence, while H2O2 scavengers stabilized fLuc activity. Comparatively, RLuc8 was far less sensitive to ROS. These observations suggest that fLuc activity can be substantially altered in studies where ROS levels become elevated and can potentially lead to ambiguous or misleading findings

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Current and emerging developments in subseasonal to decadal prediction

Weather and climate variations of subseasonal to decadal timescales can have enormous social, economic and environmental impacts, making skillful predictions on these timescales a valuable tool for decision makers. As such, there is a growing interest in the scientific, operational and applications communities in developing forecasts to improve our foreknowledge of extreme events. On subseasonal to seasonal (S2S) timescales, these include high-impact meteorological events such as tropical cyclones, extratropical storms, floods, droughts, and heat and cold waves. On seasonal to decadal (S2D) timescales, while the focus remains broadly similar (e.g., on precipitation, surface and upper ocean temperatures and their effects on the probabilities of high-impact meteorological events), understanding the roles of internal and externally-forced variability such as anthropogenic warming in forecasts also becomes important. The S2S and S2D communities share common scientific and technical challenges. These include forecast initialization and ensemble generation; initialization shock and drift; understanding the onset of model systematic errors; bias correct, calibration and forecast quality assessment; model resolution; atmosphere-ocean coupling; sources and expectations for predictability; and linking research, operational forecasting, and end user needs. In September 2018 a coordinated pair of international conferences, framed by the above challenges, was organized jointly by the World Climate Research Programme (WCRP) and the World Weather Research Prograame (WWRP). These conferences surveyed the state of S2S and S2D prediction, ongoing research, and future needs, providing an ideal basis for synthesizing current and emerging developments in these areas that promise to enhance future operational services. This article provides such a synthesis

Synthesis and Testing of Azaindole Inhibitors of Arp2/3 Complex

We worked towards designing new candidate molecules for synthesis in collaboration with Dr. Zoe Cournia at the Bioacademy of Athens. We provided her with some new molecule designs we are interested in—specifically “azaindole” molecules, meaning molecules incorporating a nitrogen as an important element in a particular molecular framework. We continue to exchange information and results that help move our synthesis project forward. The two students on this project spent the majority of their time performing organic synthesis, which is the process of building relatively complex molecules from simpler molecular building blocks. Emily Tiedemann worked primarily on applying the synthesis techniques that had worked previously in our group on the “non-azaindole” family of molecules to the new “azaindole” family. She found that several of the reactions worked equally as well as before, but had to change the chemicals and approaches used to succeed in other synthesis attempts. Natalie Wade focused on scaling up an aspect of the routine synthesis we do in our lab with the goals of making our lab activities cheaper, safer, and more environmentally friendly. Both students synthesized many new molecules and analyzed them for purity using our department’s instrumentation. Neither student got to a “final compound” stage during the summer 2019 period of work, meaning that we do not have biochemical activity results yet for the new molecules we are working towards. However, both students are very close to a final compound and will almost certainly have some interesting biochemistry results following a trip to Eugene during this spring semester, and hopefully those will be able to be presented for the first time at the Linfield College Student Symposium in May 2020

Progress Towards Synthesis of Azaindole Derivatives of Arp2/3 Complex Inhibitor CK-666

The primary objective of this research is synthesize a derivative of 2-methyl-7-azaindole and to determine its potency of inhibition of the Actin Related Protein (Arp 2/3) complex. A potent Arp2/3 inhibitor may be of interest in clinical anti-cancer and anti-tumor applications. Additionally, an Arp2/3 inhibitor with nanomolar potency could be used to advance basic actin dynamics research. Herein the organic synthetic efforts towards the 2-methyl-7-azaindole derivative of the known Arp2/3 inhibitor CK-666 are described. Spectroscopy as it informs our continuing efforts to synthesize our target is discussed. Further synthesis plans are discussed as they relate to successfully reaching our target compound

A Boron Protecting Group Strategy for 1,2-Azaborines

Upon reaction with either molecular oxygen or di-<i>tert</i>-butylperoxide in the presence of a simple copper­(I) salt and an alcohol, a range of 1,2-azaborines readily exchange <i>B</i>-alkyl or <i>B</i>-aryl moieties for <i>B</i>-alkoxide fragments. This transformation allows alkyl and aryl groups to serve for the first time as removable protecting groups for the boron position of 1,2-azaborines during reactions that are not compatible with the easily modifiable <i>B</i>-alkoxide moiety. This reaction can be applied to synthesize a previously inaccessible BN isostere of ethylbenzene, a compound of interest in biomedical research. A sequence of epoxide ring opening using N-deprotonated 1,2-azaborines followed by an intramolecular version of the boron deprotection reaction can be applied to access the first examples of BN isosteres of dihydrobenzofurans and benzofurans, classes of compounds that are important to medicinal chemistry and natural product synthesis

Oregon vegetable digest ; Vol. 17 No. 4

Published October 1968. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo