6533b86dfe1ef96bd12c952b

RESEARCH PRODUCT

Synthesis and activity of phosphinic tripeptide inhibitors of cathepsin C

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description

Phosphinic tripeptide analogues Gly-Xaaψ[P(O)(OH)CH2]-Gly have been developed as inhibitors of cathepsin C (DPP I), a lysosomal, papain-like cysteine protease. The target compounds were synthesised by addition of methyl acrylate to the appropriate phosphinic acids followed by the N-terminus elongation using mixed anhydride procedure. The latter step has been demonstrated to be a suitable method for N-terminal extension of the phosphinic pseudopeptide analogues without requirement of hydroxyphosphinyl protection. The title compounds appeared to be moderate inhibitors of the cathepsin C. However, although designed as transition state analogues, they surprisingly exhibited noncompetitive mode of binding to cathepsin C. Differences in kinetics of C-terminal acids and esters have been additionally observed. Phosphinic tripeptides were designed and synthesised as transition state analogue inhibitors of cathepsin C. Surprisingly, they revealed noncompetitive mode of binding with different kinetics for C-terminal acids comparing to the corresponding esters.