Abstract: The subject of the present invention are specific phospholipidesters of clofarabine and the use of such lipidesters in the treatment of tumors.

Abstract: The subject of the present invention is specific lipidesters of halogenated nucleotides of the following formula wherein R1, R2, R3, X and Y are defined as described herein and salts thereof, said compounds have anti-cancer properties; pharmaceutical compositions containing the compounds, a method of synthesizing the compounds, and a method of using the compounds for treating malignant tumors.

Abstract: A membranous enzyme not yet described in the state-of-the-art can be extracted from cellular membrane fractions of blood leukocytes or monocytes/macrophages. Also disclosed is the use of substrates of this enzyme to prepare medicaments that contain these substrates as pharmaceutical active substance. These medicaments are useful to direct pharmacologically active substances to target cells and to enrich target cells with said substances. Also disclosed are in-vitro research systems containing this enzyme used to detect other substrates of this enzyme.