6002-06-8Relevant academic research and scientific papers
Possible involvement of radical intermediates in the inhibition of cysteine proteases by allenyl esters and amides
Takeuchi, Yoshio,Fujiwara, Tomoya,Shimone, Yoshihito,Miyataka, Hideki,Satoh, Toshio,Kirk, Kenneth L.,Hori, Hitoshi
scheme or table, p. 6202 - 6205 (2009/08/07)
In order to investigate crystallographically the mechanism of inhibition of cysteine protease by α-methyl-γ,γ-diphenylallenecarboxylic acid ethyl ester 3, a cysteine protease inhibitor having in vivo stability, we synthesized N-(α-methyl-γ,γ-diphenylallenecarbonyl)-l-phenylalanin e ethyl ester 4. Reaction of 4 with thiophenol, the SH group of which has similar pKa value to that of cysteine protease, produced oxygen-mediated radical adducts 6 and 7 in ambient air but did not proceed under oxygen-free conditions. Catalytic activities of two thiol enzymes including cathepsin B were also lowered in the absence of oxygen. These results suggest that cysteine protease can act through an oxygen-dependent radical mechanism.
