The area of covalent inhibitors is gaining momentum due to recently introduced clinical drugs, but libraries of these compounds are scarce. Multicomponent reaction (MCR) chemistry is well known for its easy access to a very large and diverse chemical space. Here, we show that MCRs are highly suitable to generate libraries of electrophiles based on different scaffolds and three-dimensional shapes and highly compatible with multiple functional groups. According to the building block principle of MCR, acrylamide, acrylic acid ester, sulfurylfluoride, chloroacetic acid amide, nitrile, and α,β-unsaturated sulfonamide warheads can be easily incorporated into many different scaffolds. We show examples of each electrophile on 10 different scaffolds on a preparative scale as well as in a high-throughput synthesis mode on a nanoscale to produce libraries of potential covalent binders in a resource- and time-saving manner. Our operational procedure is simple, mild, and step economical to facilitate future covalent library synthesis.
A robust, safe and magnetically recoverable palladium catalyst was synthesized by anchoring Pd(II) onto ethylenediaminetetraacetic acid-coated Fe 3 O 4 (Fe 3 O 4 @EDTA) magnetic nanoparticles. The Fe 3 O 4 magnetic nanoparticle-supported Pd(II)-EDTA complex catalyst thus obtained was characterized using scanning and transmission electron microscopies, thermogravimetric analysis, vibrating sample magnetometry, X-ray diffraction, and inductively coupled plasma atomic emission and Fourier transform infrared spectroscopies. Fe 3 O 4 @EDTA-Pd(II) was screened for the Suzuki reaction and reduction of nitro compounds in water. The Pd content of the catalyst was measured to be 0.28 mmol Pd g À1 . In addition, the Fe 3 O 4 @EDTA-Pd catalyst can be easily separated and recovered with an external permanent magnet. The anchored solid catalyst can be recycled efficiently and reused five times with only a very slight loss of catalytic activity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.