Bs. Orlek et al., DESIGN AND SYNTHESIS OF NOVEL MUSCARINIC AGONISTS CONTAINING THE 1,2,4-TRIAZINE RING AS AN ESTER BIOISOSTERE, Bioorganic & medicinal chemistry letters, 4(12), 1994, pp. 1411-1414
Replacement of the ester group in methyl quinuclidine-3-carboxylate 1
with a 1,2,4-triazine ring afforded the high affinity muscarinic parti
al agonist 6a. Analogues 7a, 7b and 7d which incorporate the 1-azabicy
clo[2.2.1]heptane ring also display high affinity for muscarinic recep
tors.