Y. Aoyama et al. / Bioorg. Med. Chem. Lett. 11 (2001) 1691–1694
5. Richter, R.; Ulrich, H. Synthesis 1975, 463.
1693
6. Kuhn, N.; Schwarz, W.; Schmidt, A. Chem. Ber. 1977, 110,
1130.
7. The structures of compound 1 and 4–10 were confirmed by
1
IR, H NMR, and mass spectrometric analysis.
8. The human chymase assay was performed as follows. First,
human chymase was purified according to the method of
Takai (Takai, S.; Siota, N.; Sakaguchi, M.; Muraguchi, H.;
Matsumura, E., Miyazaki, M. Clin. Chim. Acta 1997, 265, 13).
The purified chymase was preincubated with test compounds
dissolved in DMSO at 37 ꢀC for 30 min in 0.1 M Tris–HCl (pH
8.0) containing 1.8 M NaCl, after then the chymase reaction
was started by adding succinyl-Ala-Ala-Pro-Phe-p-nitroani-
lides (Sigma Chemical Co.). The change of absorbance was
measured at 405 nm after 2 h incubation at 37 ꢀC. The IC50
value was calculated from the inhibition of p-nitroaniline for-
mation at each concentration of the test compound.
9. The inhibitory effects of compounds 1, 7, and 10 on the
enzymatic activities of seven serine proteases were evaluated
using the purified enzymes and chromogenic substrates. The
enzymes and substrates used here were as follows: N-succinyl-
Ala-Ala-Pro-Phe-pNA (Bachem) for bovine pancreatic a-chy-
motrypsin (Sigma) and human cathepsin G (Wako); Chromo-
zyme TH (Boehringer Mannheim) for human thrombin
(Sigma); N-succinyl-Ala-Ala-Phe-Arg-pNA (Bachem) for
bovine pancreatic trypsin (Sigma); N-succinyl-Ala-Ala-Val-
pNA (Bachem) for human neutrophil elastase (Athens
Research and Technology, Inc.); Chromozym PL (Boehringer
Mannheim) for human plasmin (Sigma). The assay buffer used
here was as follows: 50 mM Tris–HCl (pH=8.0) containing 2
mM CaCl2 for a-chymotrypsin, trypsin and elastase; 50 mM
Tris–HCl (pH=7.5) containing 2 mM CaCl2 for cathepsin G;
50 mM Tris–HCl (pH=7.5) containing 50 mM NaCl for
plasmin; 0.1 M Tris–HCl (pH=8.0) containing 10 mM CaCl2
and 0.1 M NaCl for thrombin.
Figure 1.
Table 3. Calculation of ring strain energies, atomic charge, and
LUMO coefficients of compounds 1 and 11
Compd
Strain energy
(kcal/mol)
Atomic charge
PM3/AM1
LUMO
coefficients
PM3/AM1
PM3/AM1
1
11
10.4/33.6
18.1/33.3
0.303/0.425
0.281/0.321
ꢁ0.0547/ꢁ0.583
ꢁ0.0049/ꢁ0.0049
10. The nomenclature of Schechter and Berger is used t0o des-
0
ignate the individual amino acid residues (P2, P1, P1 , P2 , etc.)
of0 a peptide substrate and the corresponding subsites (S2, S1,
0
0
S1 , S2 , etc.) of the enzyme. The scissile bond is the P1–P1
peptide bond. (Schechter, I.; Berger, A. Biochem. Biophys. Res.
Commun. 1967, 27, 157).
11. Kinoshita, A.; Urata, H.; Bumpus, F. M.; Husain, A. J.
Biol. Chem. 1991, 266, 19192.
12. Tanaka, T.; Minematsu, Y.; Reilly, C. F.; Travis, J.;
Powers, J. C. Biochemistry 1985, 24, 2040.
Figure 2.
13. Stein, R. L.; Strimpler, A. M.; Mori, H.; Powers, J. C.
Biochemistry 1987, 26, 1301.
14. 1,2,5-Thiadiazolidin-3-one-1,1-dioxide has been reported
as a scaffold for the mechanism-based inhibition of serine
proteases. (He, S.; Kuang, R.; Venkataraman, R.; Tu, J.;
Truong, T. M.; Chan, H.-K.; Groutas, W. C. Bioorg. Med.
Chem. 2000, 8, 1713).
Acknowledgements
The authors with to thank Prof. M. Miyazaki, Osaka
Medical College, for the kind gift of human chymase.
15. Compound 11 was prepared as follows: (a) ref 20; (b)
PhSH, NaOH, H2O–acetone; (c) TBSCl, Et3N, CH2Cl2 (83%
from 13); (d) BnBr, LDA, THF (87%); (f) n-Bu3SnH, AIBN,
PhH (92%); (g) BnBr, NaH, DMF (84%).
References and Notes
1. Aoyama, Y.; Uenaka, M.; Konoike, T.; Iso, Y.; Nishitani,
Y.; Kanda, A.; Naya, N.; Nakajima, M. Bioorg. Med. Chem.
Lett. 2000, 10, 2397. Aoyama, Y.; Uenaka, M.; Konoike, T.;
Iso, Y.; Nishitani, Y.; Kanda, A.; Naya, N.; Nakajima, M.
Bioorg. Med. Chem. Lett. 2000, 10, 2403.
2. Ihara, M.; Urata, H.; Kinoshita, A.; Suzumiya, J.; Sasa-
guri, M.; Kikuchi, M.; Ideishi, M.; Arakawa, K. Hypertension
1999, 33, 1399.
3. Kofford, M. W.; Schwartz, L. B.; Schechter, N. M.; Yager,
D. R.; Diegelmann, R. F.; Graham, M. F. J. Biol. Chem. 1997,
272, 7127.
4. Shioiri, T.; Ninomiya, K.; Yamada, S. J. Am. Chem. Soc.
1972, 94, 6203.
16. The chemical stability assay was performed as follows. To
1 mL of sodium methoxide, 10 mM solution in methanol was
added 1 mmol of compound 1 or 11 and the solution was stir-
red at 21 ꢀC. Aliquots were removed at intervals of 2 h, and