The present invention relates to a compound having the formula XXX or wherein R 1 is a C 5 or greater branched or straight chain alkyl group R 2 is hydrogen, a C 1 -C 15 branched or straight chain alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted cycloalkyl group, or R 1 and R 2 collectively form a substituted or unsubstituted fused aryl group and R 3 is one or more groups comprising, independently, hydrogen, a C 1 -C 15 branched or straight chain alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted cycloalkyl group R 6 and R 7 are, independently, hydrogen, a C 1 -C 15 branched or straight chain alkyl group, or a substituted or unsubstituted cycloalkyl group R 11 is hydrogen or a C 1 -C 15 branched or straight chain alkyl group and n is from 0 to 3, wherein one or more carbon atoms in the ring in formula XXX can optionally be replaced with a heteroatom, or the pharmaceutically-acceptable salt or ester thereof, wherein the compound is not (2E,4E,6Z,8E)-8-(3,4-dihydro-1(2H-naphthalen-1-ylidene))-3,7-dimethyl-2,4,6-octatrienoic acid or an ester thereof (2E,4E,6E,8E)-8-(3,4-dihydro-1(2H-naphthalen-1-ylidene))-3,7-dimethyl-2,4,6-octatrienoic acid or an ester thereof (2E,4E,6Z,8E)-8-(3,4-dihydro-4methyl-1(2H-naphthalen-1-ylidene))-3,7-dimethyl-2,4,6-octatrienoic acid or an ester thereof and (2E,4E,6Z,8E)-8-(3,4-dihydro-5,7-dimethyl-1(2H-naphthalen-1-ylidene))-3,7-dimethyl-2,4,6-octatrienoic acid or an ester thereof.
