A convenient synthesis of unsymmetrically substituted terphenyls of biologically active stilbenes via a double Suzuki cross-coupling protocol
作者:Daniele Simoni、Giuseppe Giannini、Pier Giovanni Baraldi、Romeo Romagnoli、Marinella Roberti、Riccardo Rondanin、Riccardo Baruchello、Giuseppina Grisolia、Marcello Rossi、Danilo Mirizzi、Francesco Paolo Invidiata、Stefania Grimaudo、Manlio Tolomeo
DOI:10.1016/s0040-4039(03)00447-7
日期:2003.3
A double Suzuki cross-coupling protocol has been devised as a practical route to a variety of terphenyls. Good chemoselectivity was observed. Unsymmetrically substituted triphenylenes were also easily prepared.
Two new series of combretastatin (CA-4) analogues have been prepared. The alkenyl motif of CA-4 was replaced either by a five-membered heterocyclic (isoxazoline or isoxazole) or by a six-membered ring (pyridine or benzene). The new compounds have been evaluated for their effects on tubulin assembly and for cytotoxic and apoptotic activities. Five compounds (18b, 20a, 21a, 34b, and 35b) demonstrated an attractive profile of cytotoxicity (IC50 < 1 muM) and apoptosis-inducing activity but poor antitubulin activity. The isoxazoline derivatives 18b, 20a, and 21a, demonstrated potent apoptotic activity different from that of natural CA-4. Their ability to block most cells in the G2 phase suggests that these compounds could act on targets different from the mitotic spindle. This would indicate activation of both the intrinsic and the extrinsic apoptotic pathways. The data suggest unambiguously that structural alteration of the stilbene motif of CA-4 can be extremely effective in producing potent apoptosis-inducing agents.