Structure-activity relationships of anthraquinone derivatives derived from bromaminic acid as inhibitors of ectonucleoside triphosphate diphosphohydrolases (E-NTPDases)

Younis Baqi, Stefanie Weyler, Jamshed Iqbal, Herbert Zimmermann, Christa E. Müller

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38 Citations (Scopus)


Reactive blue 2 (RB-2) had been characterized as a relatively potent ectonucleoside triphosphate diphosphohydrolase (E-NTPDase) inhibitor with some selectivity for NTPDase3. In search for the pharmacophore and to analyze structure-activity relationships we synthesized a series of truncated derivatives and analogs of RB-2, including 1-amino-2-sulfo-4- ar(alk)ylaminoanthraquinones, 1-amino-2-methyl-4-arylaminoanthraquinones, 1-amino-4-bromoanthraquinone 2-sulfonic acid esters and sulfonamides, and bis-(1-amino-4-bromoanthraquinone) sulfonamides, and investigated them in preparations of rat NTPDase1, 2, and 3 using a capillary electrophoresis assay. Several 1-amino-2-sulfo-4- ar(alk)ylaminoanthraquinone derivatives inhibited E-NTPDases in a concentration-dependent manner. The 2-sulfonate group was found to be required for inhibitory activity, since 2-methyl-substituted derivatives were inactive. 1-Amino-2-sulfo-4-p-chloroanilinoanthraquinone (18) was identified as a nonselective competitive blocker of NTPDases1, 2, and 3 (Ki16-18 μM), while 1-amino-2-sulfo-4- (2-naphthylamino)anthraquinone (21) was a potent inhibitor with preference for NTPDase1 (Ki 0.328 μM) and NTPDase3 (Ki 2.22 μM). Its isomer, 1-amino-2-sulfo-4- (1-naphthylamino)anthraquinone (20), was a potent and selective inhibitor of rat NTPDase3 (Ki 1.5 μM).

Original languageEnglish
Pages (from-to)91-106
Number of pages16
JournalPurinergic Signalling
Issue number1
Publication statusPublished - 2009



  • Anthraquinone
  • E-NTPDase
  • Inhibitor
  • Reactive blue 2
  • Synthesis

ASJC Scopus subject areas

  • Cell Biology
  • Molecular Biology
  • Cellular and Molecular Neuroscience

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