Medicinal Chemistry Research

, Volume 22, Issue 9, pp 4069–4074 | Cite as

Benzothiazole Schiff-bases as potential imaging agents for β-amyloid plaques in Alzheimer’s disease

  • Changsheng Gan
  • Lin Zhou
  • Zhenzhen Zhao
  • Haoshu Wang
Original Research


A series of benzothiazole Schiff-bases as potential diagnostic imaging agents targeting β-amyloid (Aβ) plaques in Alzheimer’s disease (AD) were synthesized and evaluated. When in vitro binding studies using AD homogenate with [125I] 6-iodo-2-(4′-dimethyl- amino)-phenyl-imidazo[1,2-α]pyridine ([125I]IMPY) as the reference ligand were carried out with the derivatives, the compounds showed high to low binding affinities for AD homogenate at the K i values ranged from 4.38 to 514.65 nM, depending on the substitution on the phenyl ring. Fluorescent staining in vitro showed that one compound with a N,N-dimethylamino group intensely stained Aβ plaques within brain sections of postmortem AD patients. The results strongly suggest that these derivatives are worthy of further study and may be a useful amyloid imaging agents for early detection of amyloid plaques in the brain of AD.

Graphical Abstract


Alzheimer’s disease Amyloid plaques Benzothiazole Schiff-bases Binding affinity 



We are grateful to the Key Laboratory of Brain Function and Disease, Chinese Academy of Sciences for financial support.


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • Changsheng Gan
    • 1
  • Lin Zhou
    • 1
  • Zhenzhen Zhao
    • 1
  • Haoshu Wang
    • 1
  1. 1.Engineering Research Center of Bio-process of Ministry of EducationHefei University of TechnologyHefeiPeople’s Republic of China

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