FIELD: chemistry of metalloorganic compounds, medicine, pharmacy. SUBSTANCE: invention describes a novel compound of platinum of the formula (I) 
where X means halogen atom; B means independently hydroxyl group or carboxylate group containing 1-6 carbon atoms; A means group 
-R where R is tricyclic hydrocarbon fragment containing 10-14 carbon atoms that can be optionally substituted in tricyclic ring with one or two alkyl group(s) being each contains 1-4 carbon atoms; inclusion complex of indicated complex of platinum with beta- or gamma- cyclodextrin that can be optionally substituted with hydroxyl groups containing 1-6 carbon atoms; method of synthesis of complex compound of the formula (I) based on oxidation of complex of bivalent platinum of the formula (II) indicated in the invention claim with hydrogen peroxide and optional substitution of hydroxyl groups in synthesized product with carboxylate groups by effect of acylating agent, and pharmaceutical composition. The disclosed complexes can be used as such or as component of pharmaceutical composition for treatment of oncological diseases. EFFECT: improved method of synthesis, valuable antitumor properties of compounds. 8 cl, 12 tbl, 11 ex
