5174
M. Tanaka et al. / Bioorg. Med. Chem. Lett. 14 (2004) 5171–5174
Derian, S. A.; Addo, M. F.; Andrade-Gordon, P.;
(2H, t, J = 4.0Hz), 6.71–6.80 (4H, m), 6.85–7.03(4H, m),
7.13–7.18 (4H, m), 7.42 (1H, s), 7.54–7.61 (2H, m). Anal.
Calcd for C24H21N5O2: C, 70.06; H, 5.14; N, 17.02.
Found: C, 69.89; H, 5.38; N, 17.07.
Eckardt, A. J.; Conway, B. R.; Westover, L.; Xu, J. Z.;
Look, R.; Demarest, K. T.; Emanuel, S.; Maryanoff, B. E.
Bioorg. Med. Chem. Lett. 2003, 13, 3049.
4. Milton, R.; Aiello, L.; Davis, M.; Sheetz, M. J.; Arora, V.;
Vignati, L. Diabetes 2003, 52(Suppl. 1), Abst 544.
5. Faul, M. M.; Gillig, J. R.; Jirousek, M. R.; Ballas, L. M.;
Schotten, T.; Kahl, A.; Mohr, M. Bioorg. Med. Chem.
Lett. 2003, 13, 1857.
6. (a) Goekjian, P. G.; Jirousek, M. R. Expert Opin. Inv.
Drug. 2001, 10, 2117; (b) Van Gijn, R.; Zuidema, X.; Bult,
A.; Beijnen, J. H. J. Oncol. Pharm. Pract. 1999, 5, 166.
7. Davis, P. D.; Hill, C. H.; Lawton, G.; Nixon, J. S.;
Wilkinson, S. E.; Hurst, S. A.; Keech, E.; Turner, S. E. J.
Med. Chem. 1992, 35, 177.
8. 3-Anilino-4-arylmaleimides were reported as GSK-3 selec-
tive inhibitors, but there was no mention of PKCb
inhibition or of anilino-monoindolylmaleimides: Smith,
D. G.; Buffet, M.; Fenwick, A. E.; Haigh, D.; Ife, R. J.;
Saunders, M.; Slingsby, B. P.; Stacey, R.; Ward, R. W.
Bioorg. Med. Chem. Lett. 2001, 11, 635.
13. Prade, L.; Engh, R. A.; Girod, A.; Kinzel, V.; Huber, R.;
Bossemeyer, D. Structure 1997, 5, 1627.
14. PKC enzyme assay system (Amersham Biosciences) and
[c-32P]-ATP were used for enzyme assay. All PKC
isozymes (recombinant human PKC a, b1, b2, c, and e)
were purchased from EMD Biosciences. The assay mix-
ture (final volume 21lL) contained 1.2mM calcium
acetate for PKC a, b1, b2, and c or 0.1mM EGTA for
PKCe, 0.6lg L-a-phosphatidyl-L-serine, 0.05lg phorbol
12-myristate 13-acetate (PMA), 3mM dithiothreitol,
0.1mM ATP, 7mM MgCl2, 2.5kBq [c-32P]-ATP, 90mM
substrate peptide (RKRTLRRL-OH), enzyme (PKC a:
0.9mU, b1: 0.4mU, b2: 9.5mU, c: 28.7mU, e: 5.1mU),
and compound dissolved in DMSO (final concentration
4.8%). Assay mixture was incubated for 15min at 37°C,
and reaction was stopped by addition of 300mM H3PO4.
Assay mixture was blotted onto phosphocellulose paper
(Whatman), washed with 75mM H3PO4 and evaluated by
IP-autoradiography (Fujifilm). The IC50 value was calcu-
lated in a semi-logarithmic proportional manner from the
two points enclosing 50% inhibition.
15. Aliphatic amine derivatives were reported as micromolar
PKC inhibitors: He, M.; Buisine, E.; Tartar, A.; Sergh-
eraert, C. Bioorg. Med. Chem. Lett. 1994, 4, 2845.
16. Neither compound 1 nor 4c inhibited PKA up to the
concentration of 10lM. MESACUP protein kinase assay
kit (Medical & Biological Laboratories) was used for PKA
enzyme assay. PKCe was chosen as a representative of
calcium-independent PKCs to discuss the selectivity since
this isozyme possesses the highest degree of overall
identity with PKCb among this type of PKCs.
9. (a) Rooney, C. S.; Randall, W. C.; Streeter, K. B.; Ziegler,
C.; Cragoe, E. J.; Schwam, H.; Michelson, S. R.; William,
H. W.; Eichler, E.; Duggan, D. E.; Ulm, E. H.; Noll, R.
J. Med. Chem. 1983, 26, 700; (b) Neel, D. A.; Jirousek,
M. R.; McDonald, J. H., III Bioorg. Med. Chem. Lett.
1998, 8, 47.
10. All compounds gave appropriate physical spectra data (1H
NMR, IR, and elemental analysis and/or FAB-MS).
11. 3-Anilino-4-(1H-indol-3-yl)-1H-pyrrole-2,5-dione (4c): H
1
NMR (300MHz, DMSO-d6) d 6.64–6.95 (6H, m), 7.22
(2H, d, J = 8.1Hz), 7.32 (2H, d, J = 8.0Hz), 9.04 (1H, s),
10.60 (1H, s), 11.16 (1H, br s). Anal. Calcd for
C18H13N3O2: C, 71.28; H, 4.32; N, 13.85. Found: C,
71.10; H, 4.70; N, 13.86.
12. 3-[1-(3-Imidazol-1-ylpropyl)-1H-indol-3-yl]-4-anilino-1H-
pyrrole-2,5-dione (6l): 1H NMR (300MHz, CDCl3) d 2.20
(2H, quintet, J = 4.0Hz), 3.77 (2H, t, J = 4.0Hz), 3.97
17. Davis, P. D.; Elliott, L. H.; Harris, W.; Hill, C. H.; Hurst,
S. A.; Keech, E.; Kumar, M. K. H.; Lawton, G.; Nixon,
J. S.; Wilkinson, S. E. J. Med. Chem. 1992, 35, 994.