Abstract: There is provided compounds of formula I, wherein R1, R2, R3, R41 to R46, X, Y and Z have meanings given in the description, which compounds are useful in the prophylaxis and in the treatment of arrhythmias, in particular atrial and ventricular arrhythmias.

Abstract: There is provided a process for the preparation of a sulfonic acid salt of formula I, or a solvate thereof, which process comprises hydrogenating a sulfonic acid salt of formula II, or a solvate thereof; in the presence of a solvent system consisting essentially of water, a C3-5 secondary alkyl alcohol and no more than 15% v/v of another organic solvent, wherein the sulfonic acid salt of formula I is optionally, without isolation, converted to a compound of formula IX, or a pharmaceutically-acceptable derivative thereof, wherein R1, R2, R3, R6, R7, R8, A, B and D have meanings given in the description.

Abstract: There is provided processes for the preparation of various compounds, including compounds of formulae I, IV and VII, or salts and/or solvates thereof, which compounds are useful intermediates in the synthesis of certain oxabispidines having antiarrhythmic activity, such as compounds of formula XI wherein R1?, R15?, R16?, R18? and D have meanings given in the description.

Abstract: There is provided compounds of formula I, wherein R1, R2, R3, R41 to R46, X, Y and Z have meanings given in the description, which compounds are useful in the prophylaxis and in the treatment of arrhythmias, in particular atrial and ventricular arrhythmias.