Azodicarboxamides: A New Class of Cysteine Proteinase Inhibitor for Hepatitis A Virus and Human Rhinovirus 3C Enzymes
摘要:
Hepatitis A virus (HAV) 3C and human rhinovirus (HRV) 3C cysteine proteinases have been shown to be essential for viral maturation and infectivity through the cleavage of a viral polyprotein precursor. A number of bis-hydrazides (e.g., 11-14), analogous to nanomolar inhibitors of cathepsin K, were synthesized and tested for effectiveness against HAV 3C and HRV 3C proteinases, but these compounds showed no significant inhibition of the viral enzymes. However, oxidation of the bis-hydrazides to the corresponding azodicarboxamides gave potent, irreversible inhibitors with IC50's in the low micromolar range. These compounds probably act. by adding the active site thiol to the azo moiety in a Michael fashion to give a covalent complex, which was detected by electrospray mass spectrometry. Azodicarboxamide 16 was shown to have a rate constant (k(inact)/k(I)) of 35 644 M-1 min(-1).
Azodicarboxamides: A New Class of Cysteine Proteinase Inhibitor for Hepatitis A Virus and Human Rhinovirus 3C Enzymes
摘要:
Hepatitis A virus (HAV) 3C and human rhinovirus (HRV) 3C cysteine proteinases have been shown to be essential for viral maturation and infectivity through the cleavage of a viral polyprotein precursor. A number of bis-hydrazides (e.g., 11-14), analogous to nanomolar inhibitors of cathepsin K, were synthesized and tested for effectiveness against HAV 3C and HRV 3C proteinases, but these compounds showed no significant inhibition of the viral enzymes. However, oxidation of the bis-hydrazides to the corresponding azodicarboxamides gave potent, irreversible inhibitors with IC50's in the low micromolar range. These compounds probably act. by adding the active site thiol to the azo moiety in a Michael fashion to give a covalent complex, which was detected by electrospray mass spectrometry. Azodicarboxamide 16 was shown to have a rate constant (k(inact)/k(I)) of 35 644 M-1 min(-1).
Synthesis and testing of azaglutamine derivatives as inhibitors of Hepatitis A Virus (HAV) 3C proteinase
作者:Y Huang
DOI:10.1016/s0968-0896(99)00006-1
日期:1999.4
Hepatitis A virus (HAV) 3C proteinase is a picornaviral cysteine proteinase that is essential for cleavage of the initially synthesized viral polyprotein precursor to mature fragments and is therefore required for viral replication in vivo. Since the enzyme generally recognizes peptide substrates with L-glutamine at the P-1 site, four types of analogues having an azaglutamine residue were chemically synthesized: hydrazo-o-nitrophenylsulfenamides A (e.g. 16); frame-shifted hydrazo-o-nitrophenylsulfenamides B (e.g. 25-28); the azaglutamine sulfonamides C (e.g. 7, 8, 11, 12); and haloacetyl azaglutamine analogues 2 and 3. Testing of these compounds for inhibition of the HAV 3C proteinase employed a C24S mutant in which the non-essential surface cysteine was replaced with serine and which displays identical catalytic parameters to the wild-type enzyme. Sulfenamide 16 (type A) showed no significant inhibition. Sulfenamide 27 (type B) had an IC50 of ca 100 mu M and gave time-dependent inactivation of the enzyme due to disulfide bond formation with the active site cysteine thiol, as demonstrated by electrospray mass spectrometry. Sulfonamide 8 (type C) was a weak competitive inhibitor with an IC50 of approximately 75 mu M. The haloacetyl azaglutamine analogues 2 and 3 were time-dependent irreversible inactivators of HAV 3C proteinase with rate constants k(obs)[I] of 680 M-1 s(-1) and 870 M-1 s(-1), respectively, and were shown to alkylate the active site thiol. (C) 1999 Elsevier Science Ltd. All rights reserved.
Azodicarboxamides: A New Class of Cysteine Proteinase Inhibitor for Hepatitis A Virus and Human Rhinovirus 3C Enzymes
作者:Richard D. Hill、John C. Vederas
DOI:10.1021/jo9915123
日期:1999.12.1
Hepatitis A virus (HAV) 3C and human rhinovirus (HRV) 3C cysteine proteinases have been shown to be essential for viral maturation and infectivity through the cleavage of a viral polyprotein precursor. A number of bis-hydrazides (e.g., 11-14), analogous to nanomolar inhibitors of cathepsin K, were synthesized and tested for effectiveness against HAV 3C and HRV 3C proteinases, but these compounds showed no significant inhibition of the viral enzymes. However, oxidation of the bis-hydrazides to the corresponding azodicarboxamides gave potent, irreversible inhibitors with IC50's in the low micromolar range. These compounds probably act. by adding the active site thiol to the azo moiety in a Michael fashion to give a covalent complex, which was detected by electrospray mass spectrometry. Azodicarboxamide 16 was shown to have a rate constant (k(inact)/k(I)) of 35 644 M-1 min(-1).