1. A pharmaceutical composition comprising a compound of formula I, II, III or IV, or a combination thereof, in Compound I, the rectangle that surrounds the alkyl chain is labeled “-2H” to indicate that there are two carbon-carbon double bonds in the alkyl chain, and in Compound III, the rectangle that surrounds the alkyl chain is labeled + oxygen to indicate that a hydroxyl group is present in the alkyl chain, in admixture with a pharmaceutically acceptable adjuvant, diluent or carrier. The pharmaceutical composition according to claim 1, wherein the composition comprises Compound I.3. The pharmaceutical composition according to claim 1, wherein the composition comprises Compound II.4. The pharmaceutical composition according to claim 1, wherein the composition comprises Compound III.5. The pharmaceutical composition according to claim 1, where the composition contains Compound IV.6. A compound of the formula I, II, III or IV, for example, an isolated compound of the formula I, II, III or IV, where in the Compound I the rectangle that surrounds the alkyl chain is marked “-2H” to indicate that there are two carbon- carbon double bonds, and in Compound III, the rectangle that surrounds the alkyl chain is labeled + oxygen to indicate that a hydroxyl group is present in the alkyl chain； intended for use as a pharmaceutical. The compound of formula I, II, III or IV according to claim 6, intended for use in the treatment or prevention of organ or tissue transplant rejection or in the treatment or prevention of an autoimmune disease or inflammatory condition, for example multiple sclerosis. A method for treating or preventing rejection1. Фармацевтическая композиция, содержащая соединение формулы I, II, III или IV или их комбинациюгде в Соединении I прямоугольник, который окружает алкильную цепь, помечен надписью «-2Н» для указания того, что в алкильной цепи присутствуют две углерод-углеродные двойные связи, и в Соединении III прямоугольник, который окружает алкильную цепь
