Abstract: A 4-fluorobiphenyl derivative of formula (I), which is useful as a cholesterol lowering agent or a lipid lowering agent because of its strong inhibitory effect on HMG-CoA reductase), and which is also useful as an intermediate for producing the above-mentioned cholesterol lowering agent or lipid lowering agent: ##STR1## wherein A is a .omega.-oxycarbonyldihydroxybutyl group, a tetrahydropyranyl group, a .omega.-oxycarbonyl-3-oxobutyl group, a formyl group, or a cyano group; R.sup.1 is a halogen atom, an alkyl group, or a group represented by R.sup.5 O--, wherein R.sup.5 is a hydrogen atom, or an alkyl group; R.sup.2 is a hydrogen atom, an alkyl group; R.sup.3 is a hydrogen atom, or an alkyl group; R.sup.5 and R.sup.2 may form a five-membered ring or a six-membered ring in combination with the oxygen atoms to which R.sup.5 and R.sup.2 are respectively bonded, and R.sup.5 and R.sup.3 may form a five-membered ring or a six-membered ring in combination with the oxygen atom to which R.sup.5 is bonded.

Abstract: A 4-fluorobiphenyl derivative of formula (I): ##STR1## wherein A is a .omega.-oxycarbonyldihydroxybutyl group of formula (II): ##STR2## wherein R.sup.2 is a hydrogen atom, an alkyl group, an alkaline metal or an alkaline earth metal; a tetrahydropyranyl group of formula (III): ##STR3## or a .omega.-oxycarbonyl-3-oxobutyl group of formula (IV): ##STR4## wherein R.sup.3 is an alkyl group; R.sup.1 is an alkyl group. This 4-fluorobiphenyl derivative is useful as an effective component for a cholesterol or lipid lowering agent.

Abstract: 4-hydroxytetrahydropyran-2-one and 3,5-Dihydroxyheptanoic acid derivatives of formula (I) and formula (II) have an inhibition effect on HMG-CoA reductase, a cholesterol value reduction effect, and an antioxidation function, thus serving as cholesterol reducing agent or lipid reducing agents: ##STR1## wherein R.sup.1 represents hydrogen, a nitro group, or -N(R.sup.4)R.sup.5 in which R.sup.4 and R.sup.5 each represent an alkyl group, an alkenyl group, an aryl group, an aralkyl group; an acyl group, an aroyl group, a carbamoyl group, or a thiocarbamoyl group, and R.sup.4 and R.sup.5 may be combined to form a cyclic amino group; and R.sup.2 and R.sup.3 each represent hydrogen or an alkyl group; and R.sup.6 represents hydrogen, an alkyl group, an alkali metal, or an alkaline earth metal.