Showing papers by "Tomas Hudlicky published in 2022"

Enzymatic dihydroxylation of aromatic compounds: Nature's unique reaction and its impact on the synthesis of natural products

Abstract: The chemoenzymatic dihydroxylation of arenes by microbial organisms represents a unique reaction found in nature. The reaction is highly stereo-, regio-, and enantioselective and yields versatile metabolites that have been exploited in the synthesis of countless natural products and useful homochiral building blocks. This chapter provides a brief history of the discovery and development of the microbial diol metabolites, their synthetic utility, and evolving applications in total synthesis. An extensive table is included to depict the many natural products and related synthetic targets attained through syntheses starting from cis-dihydrocatechols. The authors hope to highlight the utility of these chiral synthons in the assembly of natural products and to demonstrate the importance of incorporating biological methods into enantioselective synthesis.

Conversion of Natural Narciclasine to Its C-1 and C-6 Derivatives and Their Antitumor Activity Evaluation: Some Unusual Chemistry of Narciclasine

Abstract: During the search for a general, efficient route toward the synthesis of C-1 analogues of narciclasine, natural narciclasine was protected and converted to its C-1 enol derivative using a novel semi-synthetic route. Attempted conversion of this material to its triflate in order to conduct cross-coupling at C-1 resulted in a triflate at C-6 that was successfully coupled with several functionalities. Four novel compounds were fully deprotected after seven steps and subjected to evaluation for cytotoxic activity against three cancer cell lines. Only one derivative showed moderate activity compared to that of narciclasine. Spectral and physical data are provided for all new compounds.