The invention features methods for the preparation of naturally occurringtrihydroxy polyunsaturated eicosanoids and their structural analogs. Theinvention further provides new derivatives and analogs of trihydroxypolyunsaturated eicosanoids that can be prepared according to these methods.The invention also provides compositions and methods using trihydroxypolyunsaturated eicosanoid derivatives for the prevention, amelioration andtreatment of a variety of diseases or conditions associated with inflammationor inflammatory response, autoimmune diseases, rheumatoid arthritis,cardiovascular diseases, or abnormal cell proliferation or cancer.