Synthesis, crystal structure and in vitro antitumor activity of di-n-butyltin 4′-(7-oxabicyclo [2,2,1]-5-heptane-2,3-dicarboximide) benzoates

Dibutyltin(IV) oxide reacts with the cantharidin analogue, 4′-(7-oxabicyclo [2,2,1]-5-heptane-2,3-dicarboximide) benzoic acid, A, to give the complexes [(p-C8H8NO3–C6H4–COOBu2Sn)2O]2 (1) and (p-C8H8NO3–C6H4–COO)2SnBu2 (2) which had been characterized by IR and 1H, 13C, 119Sn NMR. Single X-ray crystal structure analysis has been determined for compound (1), which was analogue to most other [(RCOOBu2Sn)2O]2. The dimer features central of Bu4Sn2O2 unit with the two Bu2Sn groups being linked via bridging oxygen atom. Each tin atom adopts distorted trigonal bipyramidal structures via two carbons from a dibutyl moiety and three oxygen atoms from cantharidin derivative and bridging oxygen atom. In vitro tests show compounds 1 and 2 exhibit high cytotoxicity against P388 and HL-60.

Graphical abstractThe carboxylic acid reacts with the di-n-butyltin oxide yielding two different compounds depending on molar ratio acid/tin engaged in the reaction:bis[di-n-butyl(carboxylato)tin]oxide (compound 1) for a 1:1 ratio and di-n-butyltindi(carboxylate) (compound 2) for a 2:1 ratio. in vitro test shows that compound 1 and 2 exhibit high cytotoxicity against P388 and HL-60Figure optionsDownload full-size imageDownload as PowerPoint slide