Takuya Uchida

Synthesis and evaluation of N-substituted 1,4-oxazepanyl sordaricins as selective fungal EF-2 inhibitors

Sordaricin analogues possessing 6-methoxy-7-methyl-1,4-oxazepane moiety instead of the sugar part were synthesized and evaluated. It was found that N-substituents on the oxazepane ring had influence on biological activity. In particular, N-(2-methylpropenyl) derivative 12p exhibited potent in vitro antifungal activity. Furthermore, 12p maintained significant activity (MIC 0.25 microg/mL) against Candida albicans SANK51486 even in the presence of 20% horse serum.

Synthesis of Sordaricin Analogues as Potent Antifungal Agents against Candida albicans

Sordaricin derivatives possessing a cyclohexane ring appendage attached via an ether, thioether, amine, oxime, ester or amide linkage were synthesized and their antifungal activity was evaluated in vitro. Compounds containing a thioether bond or an oxime bond as a linkage exhibited potent MICs (< or = 0.125 microg/mL) against four Candida albicans strains including azole-low-susceptible strains. They were also active (MIC < or = 0.125 microg/mL) against Candida glabrata. Their in vivo efficacy was confirmed in a murine intravenous infection model with Candida albicans.

Anionic [3,3], [2,3] and [1,2] rearrangements of aliphatic and aromatic acyl hydrazines with NN bond cleavage

Abstract N-Acyl-N′-phenylhydrazines rearrange under basic conditions to afford o-aminophenyl-acetamides. This reaction can be rationalized in terms of [3,3] sigmatropic shifts of enolized intermediates. The Sommelet-Hauser-type and Stevens-type rearrangements of both aromatic and aliphatic acylhydrazines compete with the [3,3] rearrangement.