Cyclic ketal derivatives

摘要

Compounds are described of the formula (I) wherein R1 represents a hydrogen atom, a hydroxyl group or a group selected from -OCOCH=CHCH(CH3)(CH2)3CH3, -OCOCH=CHC(CH3)=CHCH(CH3)-CH2CH3, or -OCO-X-CH2CH(CH3)CH2CH3 [where X is -CH=CHCH(CH3)-, -CH2CH(OH)CH(CH3)-, -CH=CHC(OH)(CH3)-, -CH2CH(OH)CH2- or -CH2CH2CH(CH3)-)]; R2 represents a hydrogen atom or a hydroxyl group; R3 represents a group selected from -C(=CH2)CH(OR7)CH(CH3)CH2Ph (where R7 is a hydrogen atom or an acetyl group), -C(CH3)=CHCH(CH2R8)CH2Ph (where R8 is a hydrogen or a hydroxyl group), -C(CH2OH)=CHCH(CH3)CH2Ph, -C(=CH2)CH(OH)CH(CH2OH)CH2Ph, -C(=CH2)CH(NHCOCH3)CH(CH3)CH2Ph, -C(CH2NHCOCH3)=CHCH(CH3)CH2Ph or R4, R5 and R6 may each independently represent a hydrogen atom or a methyl group and salts thereof; with the proviso that when either of R1 and R2 represents a hydrogen atom R3 is a group selected from -C(=CH2)CH(OR7)CH(CH3)CH2Ph and -C(CH3)=CHCH(CH3)CH2Ph and when both of R1 and R2 represent hydrogen atoms R3 represents -C(CH3)=CHCH(CH3)CH2Ph. These compounds inhibit the enzyme squalene synthase and/or are intermediates for the preparation of compounds which inhibit the enzyme squalene synthase. Compounds of the invention may be formulated for use in a variety of conditions where a lowering of the level of blood plasma cholesterol in animals would be beneficial and for use in combating fungal infections in animals.