The invention relates to a method for reducing inflammation in a subject by administering to the subject an effective amount of the compound having the structure I or II: wherein, R1 is C1-C10 branched or straight chain alkyl, aryl, an amino acid, or a peptide; and R2 is hydrogen or lower C1-C5 branched or straight alkyl, or the salt or ester thereof, wherein the stereochemistry about the carbon-carbon double bond is trans. The invention further relates to a method of inducing an analgesic effect by administering to a subject an effective amount of the compound having the structure I or II. The invention further relates to a compound having the structure II, wherein, R1 is an N-acyl amino acid or peptide, or the salt or ester thereof.