Abstract: The invention relates to a compound, and pharmaceutically acceptable salts, having the formula I: wherein: R represents an alkyl or alkynyl group having 1-4 carbon atoms, or a phenyl group optionally substituted by C1-4 alkyl, alkylthio, alkoxy, halogen, nitro, acylamino, methylsulfonyl or methylenedioxy, or represents tetrahydronaphthyl, R1 represents hydrogen, trifluoro (C1-4) alkyl, alkyl or alkynyl, X represents hydrogen, alkyl having 1-4 carbon atoms, alkoxy, trifluoroalkyl, hydroxy, halogen, methylthio or aralkoxy, R2 represents: a C1-C10 alkyl group, a phenyl group optionally substituted by one or more of the following groups: a C1-C10 alkyl group, a halogen group, a nitro group, hydroxy group, and/or an alkoxy group.

Abstract: A compound or composition comprising N-formyl paroxetine of formula (1) is useful as a pharmaceutical and as a synthetic intermediate. The N-formyl paroxetine can be an impurity in paroxetine substances and methods of assaying for such an impurity are also useful.

Abstract: The synthesis of paroxetine can be made more convenient by using a solvent system comprising an aliphatic alcohol and a hydrocarbon co-solvent. The solvent system is used particularly in the hydrolysis of paroxetine phenylcarbamate and preferably uses butanol and toluene as the system.

Abstract: Paroxetine salt compositions having improved stability are formed by controlling the pH to 6.5 or less. The compositions can be made with the aide of water without significant coloration problems. The paroxetine salts include paroxetine hydrochloride salts but preferably use paroxetine sulfonate salts such as paroxetine methane sulfonate.