Cysteine derivatives with reactive groups as potential antitumor agents
作者:B. Paul、W. Korytnyk
DOI:10.1021/jm00230a004
日期:1976.8
Cysteinederivatives having diazo ketone and chloro ketone functions have been prepared. In order to effect adequate protection for modifying the carboxyl group, cysteine was converted to a thiazolidine derivative I, which was then converted to the N-acetyl derivative VII. The active ester method or activation with DCC yielded the diazo ketone derivative VIII. Similar treatment of the parent compound
Disulphide bonds are formed at the sulphur atom of Cys(R) sulphoxides intermolecularly as well as intramolecularly, following liberation of the SH group from the co-reactant, Cys(R′), by a suitable acid.
The S-1-adamantyl (Ad) group of cysteine is more stable to TFA treatment than the S-p-methoxybenzyl (MBzl) group, but is cleavable by 1 M trifluoromethanesulfonic acid-thioanisole in trifluoroacetic acid at 0°C within 60 min or by (CF3COO)3 Tl under similar conditions. S-Ad-cysteine is less susceptible to sulfoxide formation than the S-MBzl group. Trimethylphenyl-thiosilane is an effective reducing reagent of the sulfoxide.