The present invention, solvate or salt thereof, and a use of a compound of polyunsaturated fatty acids of formula (I) is (PUFA) derivatives include pharmaceutically acceptable mixture or racemate, the stereoisomer or stereoisomeric is in the form of things, wherein -Alk- is - (CH 2) 4 -CH (OR 2) - [trans] CH = CH- [cis] CH = CH -, - (CH 2) 4 - [cis] CH = CH- [trans] CH = CH-CH (OR 2) -, - CH (OR 2) - [trans] CH = CH- [cis] CH = CH-CH 2 - [cis] CH = CH- ( or [cis] CH = CH-, - - CH 2) 3 -, - (CH 2) 3 -CH (OR 2) - [trans] CH = CH- [cis] CH = CH-CH 2 (CH 2) R 1 is either hydrogen atom R 1 or is C 1 is a - 3 - [cis] CH = CH-CH 2 - [cis] CH = CH- [trans] CH = CH-CH (OR 2) 10-membered heterocyclic ring group 10-membered heteroaryl -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 6 -C 10 aryl, 5, 5 or C 3 -C 7 carbocycle or is R 1 is formula -CH 2 -CH (OR 3) -CH 2 - or a group of (OR 4), each independently a hydrogen atom or R 3 and R 4 - (C = O) or R 1 is a group is characterized in that it is an aliphatic group it is characterized by a -R 6, having 29 carbon atoms from 3 to R 6 is the formula - (CH 2 OCH 2) m A group OH, or a group and wherein m is an integer of from 1 to 200 has drug moiety or R 1 each independently each R 2 is identical or different and hydrogen atom, or a group - a (C = O) -R 5, R 5 is C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 6 -C 10 aryl, 5 or is an aliphatic group or of a 10-membered ring heterocyclic group heteroaryl, 5 or C 3 -C 7 to 10 carbon ring-membered ring, or having 29 carbon atoms from 3 to R 5, or R 5 groups wherein the There is a drug moiety formula or - a group (CH 2 OCH 2) n OH, groups, characterized in that n is an integer of from 1 to 200 represents a drug moiety or and C 1 -C 4 alkoxy and hydrogen and different, C 2 -C are the same or which is unsubstituted or substituted aliphatic group each a moiety of the alkyl, alkenyl, and alkynyl is identical or different and R "4 alkenyloxy, C 1 -C 4 haloalkyl, C 2 -C 4 haloalky
