Tags: Organic Seminar

Fischer carbene complexes with six valence electrons, characterized by a singlet carbene center, demonstrate an amphiphilic nature.1 The transition metal carbene complexes share similarities with Fischer carbene complexes, potentially functioning as both nucleophiles and electrophiles.2 This duality enables chemists to accomplish intricate transformations, such as C-H bond insertion or cyclopropanation. Despite their utility, the synthetic…
The concept of click chemistry was first introduced by Sharpless and his coworkers in 20011 , with the copper-mediated azide-alkyne cycloaddition (CuAAC) being the first click reaction to be introduced. Although a robust and precise reaction, ligating azides with terminal alkynes to afford 1,4-disubstituted triazoles, CuAAC was inherently limited due to its utilization of toxic copper metal as well as its limiting requirement for pre-…
Current batch enzymatic processes to important semi-synthetic beta-lactam antibiotics, such as amoxicillin and cephalexin, suffer from yield and selectivity limitations, owing to primary and secondary hydrolysis side reactions (see Figure). Through continuous flow and reactive crystallization of the beta-lactam product, we sought to suppress primary hydrolysis and prevent secondary hydrolysis. Indeed, we found higher yields than in homogenous…
Thioglycosides and thiasugars both have a long history in bioorganic and medicinal chemistry 1-7 but it is widely considered that they are less “active” than the parent sugars. In our research, we sought to rationalize an application of thioglycosides, thiasugar glycosides, and their dithia-analogs in bio-organic and medicinal chemistry.We were driven by our discovery that the dithiasugar analogs of the short β-(1→3)-glucan, laminaritriose…
Peptide cyclization methods are useful in the development of therapeutic peptide leads with improved metabolic stability properties. To develop residue-selective peptide cyclization strategies, we draw inspiration from cyclic and lassoed peptide natural product scaffolds that exhibit diverse biological activities. For example, the reactive phenolic linkages found in both the arylomycin and vancomycin families of antibacterial natural products…
The high prevalence of aromatics in natural products and potential drug candidates makes them intriguing candidates for continued development of C-H functionalization reactions that proceed with high positional selectivity. Achieving site-selectivity can be a steep challenge as when there is a lack of appropriate directing groups or substitution patterns, more than one product isomer is commonly produced. Therefore, the development of aromatic C…