Compounds of formula I
 wherein R¹, R², Q, X and Y have various significances,
in free acid form, or in the form of an ester or δ-lactone thereof, or in salt form as appropriate, are described.
They are indicated for use as hypolipoproteinemic and anti-atherosclerotic agents. They may be obtained by reduction, hydrolysis, deprotection or oxidation of appropriate starting compounds, and variously interconverted by e.g. hydrolysis, salt formation, esterification and/or lactonisation.  
                            式I中的化合物,其中R¹、R²、Q、X和Y具有不同的含义,在
游离酸形式中,或者以其酯或δ-内酯的形式,或者以盐的形式描述。它们被指定用作降低脂蛋白和
抗动脉粥样硬化药物。它们可以通过还原、
水解、去保护或氧化适当的起始化合物获得,并通过
水解、盐形成、酯化和/或内酯化等方法进行各种互变。