Synthesis and biological activity of selective azasugar-based TACE inhibitors

Article abstract of DOI:10.1016/j.bmcl.2003.12.091

A series of azasugar-based hydroxamic acid derivatives bearing 2R,3R,4R,5R-configuration is described. Compound 4c with 4,5-O-acetonide group showed excellent in vitro potency against TACE, with high selectivity over MMP-1 and moderate selectivity over MM

Full text of DOI:10.1016/j.bmcl.2003.12.091

Bioorganic & Medicinal Chemistry Letters 14 (2004) 1569–1572
Synthesis and biological activity of selective azasugar-based
TACE inhibitors
Takahiro Tsukida,a,b,*,y Hideki Moriyama,a,b Yoshimasa Inoue,b Hirosato Kondo,b,y
Kohichiro Yoshinob and Shin-Ichiro Nishimurac,*
aJapan Bioindustry Association, Hokkaido Collaboration Center, N-21, W-12, Kita-Ku, Sapporo 001-0021, Japan
bR&D Laboratories, Nippon Organon K.K., 1-5-90, Tomobuchi-cho, Miyakojima-ku, Osaka 534-0016, Japan
cDivision of Biological Sciences, Graduate School of Science, Hokkaido University, N-21, W-11, Kita-Ku,
Sapporo 001-0021, Japan
Received 28 October 2003; accepted 20 December 2003
Abstract—A series of azasugar-based hydroxamic acid derivatives bearing 2R,3R,4R,5R-configuration is described. Compound 4c
with 4,5-O-acetonide group showed excellent in vitro potency against TACE, with high selectivity over MMP-1 and moderate
selectivity over MMP-3 and MMP-9.
# 2004 Elsevier Ltd. All rights reserved.
1. Introduction
inhibitors of TACE.8 Actually, several MMP/TACE
inhibitors have already entered clinical trials for the
treatment of RA and cancer.9 However, in order to
minimize detrimental side effects, such as muscle and
joint pains, successful design of selective TACE inhibi-
tors would be necessary. Recently, several TACE inhi-
bitors including compound 1 with selectivity over
MMP-1 bearing butyn-2-yloxy group have been repor-
ted (Fig. 1).10
Tumor necrosis factor a (TNF-a), a major immunomo-
dulatory and proinflammatory cytokine, has been
implicated in the pathogenesis of a number of inflam-
matory diseases including rheumatoid arthritis (RA),1
multiple sclerosis,2 type II diabetes,3 and other human
ailments. TNF-a is synthesized as
a membrane-
anchored 26 kD precursor and shed to a 17 kD soluble
form by a specific proteolytic cleavage.4 This processing
step is performed by a TNF-a converting enzyme
(TACE), a member of ADAM family of proteases clas-
sified as ADAM17.5 Therefore, agents that block
TACE, and thereby reduce levels of soluble TNF-a,
may be effective in the treatment of these diseases.6
Actually, data from human clinical trials have sup-
ported the therapeutic utility of anti-TNFa biologics,
such as Enbrel1 and Remicade1, in RA and Crohn’s
disease.7
We have already disclosed azasugar-based MMP/
TACE inhibitors 2 with four asymmetric centers. The
stereochemistry of C2-position is critical for showing
potent inhibitory activities against MMPs and TACE,
and needs to be fixed as R-configuration. Then there are
eight stereoisomers based on three chiral centers at C3,
C4 and C5-position (Fig. 2).11,12 We have already pre-
pared their several stereoisomers 3a–e with different
MMP/TACE inhibitory profiles, however, these comp-
ounds were not necessarily TACE selective inhibitors.
A large number of non-specific inhibitors of matrix
metalloproteases (MMPs) have been shown to be potent
* Corresponding authors. Tel.: +81-6-6401-8199 (T. T.); tel.: +81-11-
706-9043; fax: +81-11-706-9042 (S.-I. N.); e-mail: takahiro.tsukida@
shionogi.co.jp; shin@glyco.sci.hokudai.ac.jp
y
Present address: Manufacturing Technology R&D Laboratories,
Shionogi & Co., Ltd, 1-3 Kuise Terajima 2-chome, Amagasaki,
Hyogo 660-0813, Japan.
Figure 1. Representative TACE inhibitor.
0960-894X/$ - see front matter # 2004 Elsevier Ltd. All rights reserved.
doi:10.1016/j.bmcl.2003.12.091

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T. Tsukida et al. / Bioorg. Med. Chem. Lett. 14 (2004) 1569–1572
of acetonide group of 5 was easily performed by the
cleavage and successive reprotection of 4,5-O-acetonide
in acidic condition to provide compound 6. Compound
6 was subjected to the treatment of methyl iodide in the
presence of silver oxide, to provide 7 in good yield. The
hydrogenolysis of 5, 6 and 7 with 10% Pd–C under
hydrogen, and then the corresponding phenolic hydroxyl
groups were alkylated with 1-bromo-2-butyne in the
presence of potassium carbonate in CH3CN to afford
compounds 8, 9 and 10, respectively. The aminolysis of
8, 9 and 10 with 50% hydroxylamine solution in the
presence of sodium cyanide in MeOH, gave target com-
pounds 4e, c and d in moderate yields, respectively.
Finally, the cleavage of acetonide groups of 4e and d
afforded the target compounds 4a and b in good
yield.13
Figure 2. Azasugar-based metalloproteinase inhibitors designed.
On the other hand, it was found that compounds bear-
ing 3R,4R,5R-configuration such as 3e were stable in
aqueous solution, compared to those bearing 3R,4R,5S-
configuration.12 In addition, azasugar-based inhibitors
including compound 3e could be expected to show good
water solubility, due to the hydroxyl group at C3, C4,
C5 position. These properties are desirable for adminis-
tration of drugs such as topical application and oral
administration. Therefore, in order to discover TACE
selective inhibitors successfully, we focused on the aza-
sugar compounds having 3R,4R,5R-configuration. In
this paper, we wish to report the systematic synthesis of
azasugar-based TACE inhibitors (4a–e) bearing butyn-
2-yloxy moiety and their TACE selectivity over MMPs.12
3. Discussion
Inhibitory activities toward MMP-1, MMP-3, MMP-9
and TACE of azasugar-based derivatives 4a–e were
summarized in Table 1.14 Although, compound 4a
bearing butyn-2-yloxy moiety exhibited potent inhibi-
tory activity toward TACE, it showed moderate-high
selectivity over MMPs: 242-fold over MMP-1, 6-fold
over MMP-3 and 27-fold over MMP-9, respectively.
Compound 4b having methoxy group at C3 position
showed less selectivities over MMP-1, 3, 9, compared to
4a.
2. Chemistry
According to Scheme 1, the target compounds 4a–e
were prepared from key intermediate 5.12 The exchange
Scheme 1. (a) Muromac1, MeOH, then 2,2-dimethoxypropane, p-TsOH, DMF; (b) MeI, Ag2O , CHCl2; (c) 10% Pd–C/H2, AcOEt, then
2
1-bromo-2-butyne, K2CO3, CH3CN; (d) 50% NH2OH, NaCN, MeOH; (e) Muromac1, MeOH.

T. Tsukida et al. / Bioorg. Med. Chem. Lett. 14 (2004) 1569–1572
Table 1. Inhibitory activities against MMP-1, 3, 9 and TACE
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References and notes
1. Moreland, L. W.; Baumgartner, S. W.; Schiff, M. H.;
Tindall, E. A.; Fleischmann, R. M.; Weaver, A. L.;
Ettlinger, R. E.; Cohen, S.; Koopman, W. J.; Mohler, K.
N. Engl. J. Med. 1997, 337, 141.
2. Clements, J. M.; Cossins, J. A.; Wells, G. M.; Corkill,
D. J.; Helfrich, K.; Wood, L. M.; Pigott, R.; Stabler, G.;
Ward, G. A.; Gearing, A. J.; Miller, K. M. J. NeTACE
activity uroimmunol. 1997, 74, 85.
3. Morimoto, Y.; Nishikawa, K.; Ohashi, M. Life Sci. 1997,
61, 795.
4. (a) Aggarwal, B. B.; Kohr, W. J.; Hass, P. E.; Moffat, B.;
Spencer, S. A.; Henzel, W. J.; Bringman, T. S.; Nedwin,
G. E.; Goeddel, D. V.; Harkins, R. N. J. Biol. Chem.
1985, 260, 2345. (b) Tracy, K. J.; Cerami, A. Annu. Rev.
Med. 1994, 45, 491. (c) Aggarwal, B. B.; Natarajan, K.
Euro. Cytokine. Net. 1996, 7, 93. (d) Bemelmans, M. H. A.;
van Tits, L. J. H.; Buurman, W. A. Crit. Rev. Immunol.
1996, 16, 1.
Compd
rMMP-1
Ki (nM)a
rMMP-3
Ki (nM)a
rMMP-9
Ki (nM)a
TACE
Ki (nM)a
4a
4b
4c
4d
4e
128.22
90
>850
552.4
>850
3.30
0.43
29.60
11.5
58.05
14.24
12
77.75
98.2
118.37
0.53
1.85
0.57
0.84
1.85
5. (a) Moss, M.; Becherer, J. D.; Milla, M.; Pahel, G.;
Lambert, M.; Andrews, R.; Frye, S.; Haffner, C.; Cowan,
D.; Maloney, P.; Dixon, E. P.; Jansen, M.; Vitek, M. P.;
Mitchell, J.; Leesnitzer, T.; Warner, J.; Conway, J.; Bick-
ett, D. M.; Bird, M.; Priest, R.; Reinhard, J.; Lin, P. In
Metalloproteinases as Targets for Anti-inflammatory
Drugs; Bottomley, K. M. K., Bradshaw, D., Nixon, J. S.,
Eds.; Birkhauser: Basel, 1999; p187. (b) Killar, L.; White,
J.; Black, R.; Peschon, J. Ann. N. Y. Acad. Sci. 1999, 878,
442.
a See ref 13 for assay conditions.
Interestingly, TACE inhibitory activity of 4,5-O-acet-
onide analogue 4c was very potent and equal to that of
4c, in addition, much improved selectivity (>1491-fold)
over MMP-1 was found. Furthermore, its TACE inhi-
bition was 52-fold selective over MMP-3, and 136-fold
selective over MMP-9. Compound 4d having methoxy
group at C3 position also exhibited similar tendency as
compound 4c. This finding suggests that the difference
of conformation between monocyclic analogues 4a and
b, and bicyclic rigid analogues 4c and d would be
essential for TACE selectivity over MMPs. On the other
hand, 3,4-O-acetonide analogue 4e displayed 3-fold less
potent TACE inhibitory activity than 4c, while inhibi-
tory activities against MMPs of 4e were similar to those
of 4c. This result indicates that the conformation fixed
by 4,5-O-acetonide would be desirable for inhibitory
activity against TACE, compared to that fixed by 3,4-O-
acetonide.
6. Nelson, F. C.; Zask, A. Exp. Opin. Ther. Patents 1999, 8,
383.
7. Lorenz, H. M. Curr. Opin. Invest. Drugs 2000, 1, 188.
8. (a) McGeehan, G.; Becherer, J.; Bast, R.; Boyer, C.;
Champion, B.; Connolly, K.; Conway, J.; Furdon, P.;
Karp, S.; Kidao, S.; McElroy, A.; Nichols, J.; Pryz-
wansky, K.; Schoenen, F.; Sekut, L.; Truesdale, A.;
Verghese, M.; Warner, J.; Ways, J. Nature 1994, 370, 558.
(b) Gearing, A.; Beckett, M.; Christodoulou, M.;
Churchill, M.; Clements, J.; Davidson, A.; Drummond,
A.; Galloway, W.; Gilbert, R.; Gordon, J.; Leber, T.;
Mangan, M.; Miller, K.; Nayee, P.; Owens, K.; Patel, S.;
Thomas, W.; Wells, G.; Wood, L.; Wooly, K. Nature
1994, 370, 555.
9. (a) Rasmunssen, H. S.; McCann, P. P. Pharmacol. Ther.
1997, 75, 69. (b) Beckett, R. P.; Davidson, A. H.; Drum-
mond, A. H.; Huxley, P.; Whittaker, M. Drug Disc. Today
1996, 1, 16. (c) Santos, O.; McDermott, C. D.; Daniels,
R. G.; Appelt, K. Clin. Exp. Metastasis 1997, 15, 499. (d)
Zook, S. E.; Dagnino, R., Jr.; Deason, M. E.; Bender, S.
L.; Melnick, M. J. PCT Int. Appl. WO97/20824.
10. James, M. C.; Guixian, J.; Amy, S.; Jeremy, I. L. Bioorg.
Med. Chem. Lett. 2002, 12, 1195.
11. (a) Moriyama, H.; Tsukida, T.; Inoue, Y.; Kondo, H.;
Yoshino, K.; Nishimura, S.-I. Bioorg. Med. Chem. Lett.
2003, 13, 2737. (b) Moriyama, H.; Tsukida, T.; Inoue, Y.;
Kondo, H.; Yoshino, K.; Nishimura, S.-I. Bioorg. Med.
Chem. Lett. 2003, 13, 2741.
4. Conclusion
In conclusion, we have succeeded in synthesizing a series of
azasugar-based TACE inhibitors bearing 2R,3R,4R,5R-
configuration, which exhibited excellent selectivity over
MMP-1 and moderate selectivity over MMP-3 and
MMP-9. Especially, compound 4d with 4,5-O-acetonide
group demonstrated very potent TACE inhibitory
activity and good selectivity against MMPs compared
to monocyclic compound 4a. Now in order to obtain a
better understanding about the difference of inhibitory
activity profile of 4a, c and e, docking study of these
compounds with MMPs and TACE using computer
technique is in progress.
12. Moriyama, H.; Tsukida, T.; Inoue, Y.; Yokota, K.;
Yoshino, K.; Kondo, H.; Miura, N.; Nishimura, S.-I. J.
Med. Chem., in press.
13. All new compounds obtained satisfactory characteristics
data. Characteristics are given for a representative com-
1
pound: 4c: H NMR (DMSO-d6) d: 1.17 (s, 3H), 1.23 (s,
Acknowledgements
3H), 1.84 (t, 3H, J=2.1 Hz), 3.44 (bs, 1H), 4.07 (d, 1H,
J=6.0 Hz), 4.11 (dd, 1H, J=6.4, 7.1 Hz), 4.3–4.35 (m,
1H), 4.84 (q, 2H, J=2.1 Hz), 5.63 (bs, 1H), 7.15 (d, 2H,
J=9.1 Hz), 7.71 (d, 2H, J=9.1 Hz), 8.92 (s, 1H), 10.78 (s,
1H). MALDI-TOF: 463 (M+Na+), 479 (M+K+).
This work was supported by
‘Glycocluster Project’ from NEDO. We specially thank
Ms. E. Ishibushi for expert technical assistance.
a grant for the

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14. (a) Recombinant human collagenase-1 (MMP-1), strome-
lysin-1 (MMP-3), gelatinase B (MMP-9) and TNF-a con-
verting enzyme (TACE) were used in our studies. Assay
conditions were referred as below: Sawa, M.; Kiyoi, T.;
Kurokawa, K.; Kumihara, H.; Yamamoto, M.; Miya-
saka, T.; Ito, Y.; Hirayama, R.; Inoue, T.; Kirii, Y.;
Nishiwaki, E.; Ohmoto, H.; Maeda, Y.; Ishibushi, E.;
Inoue, Y.; Yoshino, K.; Kondo, H. J. Med. Chem. 2002,
45, 919. (b) Yoshiizumi, K.; Yamamoto, M.; Miyasaka,
T.; Ito, Y.; Kumihara, H.; Sawa, M.; Kiyoi, T.; Yama-
moto, T.; Nakajima, F.; Hirayama, R.; Kondo, H.; Ishi-
bushi, E.; Ohmoto, H.; Inoue, Y.; Yoshino, K. Bioorg.
Med. Chem. 2003, 11, 433.