As part of a research programme aimed at the synthesis of compounds with antiviral, antibacterial and antitumor properties and their spectroscopic characterization, new thiosemicarbazones deriving from natural aldehydes have been investigated. These substances contain in the same molecule both a chain with nucleophilic centres N, S with tubercolostatic activity, and a glycosidic or alkyl moiety (modified glycosides and nucleosides have recently received a great deal of attention in the fields of neoplastic diseases and viral infections). In this paper the synthesis and the characterization of these compounds by means of 1H NMR, IR, and MS techniques is reported. Biological studies have involved both inhibition of cell proliferation and apoptosis tests on human leukemia cell line U937.