A series of di- and triorganotin 3,6-dioxaheptanoates and 3,6,9-trioxadecanoates were synthesized and
characterized by H1, C13 and S117n NMR, electrospray mass and S119mn Mössbauer spectroscopy, as well as
elemental analysis. Their in vitro antitumour activity against seven tumoural cell lines of human origin, two
breast cancers (MCF-7, EVSA-T), a colon carcinoma (WiDr), an ovarian cancer (IGROV), a melanoma (M 19
MEL), a renal cancer (A 498) and a non small cell lung cancer (H 226), is reported. They are characterized by
similar inhibition doses ID50 as the analogous di- and triorganotin derivatives of 4-carboxybenzo-15-crown-5
and -18-crown-6 and in some cases by much lower ID50 values than clinically used reference compounds such
as doxorubicine and methotrexate.