Heterocycles of biological importance. Part 5. The formation of novel biologically active pyrimido[1,2-a]benzimidazoles from allenic nitriles and aminobenzimidazoles

  title={Heterocycles of biological importance. Part 5. The formation of novel biologically active pyrimido[1,2-a]benzimidazoles from allenic nitriles and aminobenzimidazoles},
  author={P. F. Asobo and Helene Wahe and J. Mbafor and A. E. Nkengfack and Z. Fomum and Emmanuel F Sopbue and D. D{\"o}pp},
  journal={Journal of The Chemical Society-perkin Transactions 1},
The reaction of allenic nitriles with 2-aminobenzimidazoles gives 2-aminopyrimido[1,2-a]benzimidazoles 5 in very good yields. The pharmacological screening of compound 5a, 5d and 5i shows that they possess slight antibiotic and antiarrythmic properties. 
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