Novel alkanoic acid derivaties

摘要

There are provided according to the invention compounds of the formula (I) or a salt or solvate thereof, wherein: n represents an integer 1 to 6; N represents an integer 1 to 15; R<1 >represents (CO)xC1-9alkyl or (CO)xC1-9fluoroalkyl, which fluoroalkyl moiety contains at least 1 fluorine atom and not more than 3 consecutive perfluorocarbon atoms wherein x represents 0 or 1; and R<2 >and R<3 >independently represent C1-3alkyl or hydrogen. There are also provided pharmaceutical aerosol formulations employing said compounds as suspension stabilising agents.