Aminopyridine carbamic acid esters: synthesis and potential as acetylcholinesterase inhibitors and acetylcholine releasers

J Pharm Sci. 1992 Apr;81(4):380-5. doi: 10.1002/jps.2600810419.

Abstract

4-Amino-3-pyridyl carbamates (2a-c) were synthesized as potential acetylcholinesterase inhibitors and acetylcholine releasers on the basis of the reported activity of the analogous N-(4-amino-3-pyridyl)-N',N'-dimethylurea (1). Although 4-amino-3-pyridyl N,N-dimethylcarbamate (2b) showed good cholinesterase inhibition [concentration that elicited a 50% reduction in the maximal enzyme response (IC50) was 13.4 microM], it had no effect on the stimulated release of [3H]acetylcholine from rat striatal slices. 4-[[(Dimethylamino)methylene]amino]-3-pyridyl N,N-dimethylcarbamate (7a), an intermediate in the synthesis of 2b, demonstrated surprisingly good cholinesterase inhibition (IC50 was 9.4 microM) but showed no activity as a release. A precursor to 7a, N-(3-hydroxy-4-pyridyl)-N',N'-dimethylformamidine (6a), showed some activity in release but was not an esterase inhibitor, whereas the precursor to 6a, 4-amino-3-pyridinol (5a), was a potent releaser. A new synthesis of 5a, based on an ortho-directed lithiation strategy, is also reported.

MeSH terms

  • Acetylcholine / metabolism*
  • Aminopyridines / chemical synthesis*
  • Aminopyridines / pharmacology
  • Animals
  • Carbamates / chemical synthesis*
  • Carbamates / pharmacology
  • Cholinesterase Inhibitors / chemical synthesis*
  • Cholinesterase Inhibitors / pharmacology
  • Corpus Striatum / drug effects
  • Corpus Striatum / metabolism
  • Male
  • Rats
  • Rats, Inbred Strains

Substances

  • Aminopyridines
  • Carbamates
  • Cholinesterase Inhibitors
  • Acetylcholine