The reaction of 1-azabicyclo[3.3.1]nonan-4-one (I) with hydroxyamine gives the corresponding oxime (II), which is reduced with LiAlH4 in THF yielding 4-amino-1-azabicyclo [3.3.1]nonane (III). Finally, this compound is condensed with 4-amino-5-chloro-2-methoxybenzoylchloride (IV).

The reaction of 1-azabicyclo[3.3.1]nonan-4-one (I) with hydroxyamine gives the corresponding oxime (II), which is reduced with LiAlH4 in THF yielding 4-amino-1-azabicyclo [3.3.1]nonane (III). Finally, this compound is condensed with 4-amino-5-chloro-2-methoxybenzoylchloride (IV).

A new synthesis of renzapride has been described: The reaction of 1-azabicyclo[3.3.1]nonan-4-one (I) with hydroxylamine and pyridine in refluxing ethanol gives the corresponding oxime (II), which is reduced with Na in refluxing pentanol yielding a mixture of the exo- and endo-amines (IIIa and IIIb). The acylation of this mixture with 4-acetamido-5-chloro-2-methoxybenzoylchloride (IV) and triethylamine in toluene affords a mixture of the exo- and endo-amides (Va and Vb), which are separated by column chromatography over alumina. The endo-isomer (Va) is finally deacetylated with NaOH in refluxing ethanol. It is obtained as crystals, m.p. > 260 C.