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Updated: Jun 8, 2026

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
A protecting group-free synthesis of deazathiamine: a step toward inhibitor design
Hong Zhao1, Luiz Pedro S de Carvalho, Carl Nathan
1Organic Synthesis Core Facility, Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, PO Box 237, New York, NY 10065, United States.
Abstract:
The discovery of 3-deazathiamine diphosphate (deazaThDP) as a potent inhibitor analog of the cofactor thiamine diphosphate (ThDP) has highlighted the need for an efficient and scalable synthesis of deazaThDP. Such a method would facilitate development of analogs with the ability to inhibit individual ThDP-dependent enzymes selectively. Toward the goal of developing selective inhibitors of the mycobacterial enzyme 2-hydroxy-3-oxoadipate synthase (HOAS), we report an improved synthesis of deazaThDP without use of protecting groups. Tribromo-3-methylthiophene served as a versatile starting material whose selective functionalization permitted access to deazaThDP in five steps, with potential to make other analogs accessible in substantial amounts.
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