Compounds of formula (I); ##STR00001## wherein R.sub.1 and R.sub.2 are
the same or different and may be selected from the group consisting of a
hydrogen atom, a hydroxy group, an alkyl group, a halogen atom, an alkoxy
group, an acyloxy group, an acyl group, an alkenyl group, an alkynyl
group, an aryl group, an alkylthio group, an alkoxycarbonyl group, an
alkylsulfinyl group, an alkylsulfonyl group, an amino group, and an
alkylamino group; and X represents a carboxylic acid group, a carboxylate
group, or a carboxamide group; or any pharmaceutically acceptable salt,
solvate, complex or pro-drug thereof, with the provisos that the compound
of formula (I) is not (all-Z)-4,7,10,13,16,19-docosahexaenoic acid (DHA),
alpha-methyl DHA, alpha-methyl DHA methyl ester, alpha-methyl DHA ethyl
ester or alpha-hydroxy DHA ethyl ester, are disclosed. A fatty acid
composition and a pharmaceutical composition comprising such compounds
are also disclosed. The use of such compounds as medicaments, in
particular for the treatment of diabetes type 2, is also disclosed.