Thiazole subunits

With the aim of studying the structure-biological activity relationship, many permutations of tiazofurin that comprised variations in both the sugar and thiazole subunits were prepared. Among the sugar-modified tiazofurins. 

Leucamide A, a bioactive cyclic hexapeptide first isolated from the Australian marine sponge Leucetta microraphis and stmc-turaUy confirmed by total synthesis. It contains an unique mixed 4,2-bis-heterocycle tandem pair consisting of methyloxazole and thiazole subunit showing moderate cytotoxicity toward several tumor cell lines [S. Kehraus et al., J. Org. 

Thiazole, (III), oxazole, imidazole, and pyrazole gyrase inhibitors prepared by Charifson (3) were effective against the bacterial DNA gyrase two B subunits and used in treating antibiotic resistance. 

Transketolase Reaction. Transketolase contains a tightly bound thiamine pyrophosphate as its prosthetic group. The enzyme transfers a two-carbon glycoaldehyde from a ketose donor to an aldose acceptor. The site of the addition of the two-carbon unit is the thiazole ring of TPR Transketolase is homologous to the Ej subunit of the pyruvate dehydrogenase complex (p. 478) and the reaction mechanism is similar (Figure 20.21). 

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