The synthesis and the comparative preliminary biol. evaluation of a new pyrazole analog, (±)-5-benzyl-2-(tert-butyloxycarbonyl)-1,2,8,8a-tetrahydrocyclopropa[c]pyrazo[4,3-e]indol-4-one (I), of the CC-1065 alkylating unit (CPI) are described. I showed low cytotoxicity against L1210 murine leukemia (IC50 3064 nM) with respect to ref. compd., but contrarily to literature data, was found to be more stable to solvolysis than the natural deriv. (±)-N-Boc-CPI (pH 3, t1/2 = 212 h vs. 37 h). The results of such investigation showed that alkylation of the pyrazole nitrogen caused a loss of cytotoxic activity in vitro against tumor cells. This exptl. observation allowed us to confirm the importance of free N-H for the anticellular activity.
Synthesis, solvolytic stability and cytotoxicity of a modified derivative of CPzI, a pyrazole analog of the alkylation subunit of the antitumor agent CC-1065: Effect of the nitrogen substitution on the functional reactivity
BARALDI, Pier Giovanni;CACCIARI, Barbara;ROMAGNOLI, Romeo;
1997
Abstract
The synthesis and the comparative preliminary biol. evaluation of a new pyrazole analog, (±)-5-benzyl-2-(tert-butyloxycarbonyl)-1,2,8,8a-tetrahydrocyclopropa[c]pyrazo[4,3-e]indol-4-one (I), of the CC-1065 alkylating unit (CPI) are described. I showed low cytotoxicity against L1210 murine leukemia (IC50 3064 nM) with respect to ref. compd., but contrarily to literature data, was found to be more stable to solvolysis than the natural deriv. (±)-N-Boc-CPI (pH 3, t1/2 = 212 h vs. 37 h). The results of such investigation showed that alkylation of the pyrazole nitrogen caused a loss of cytotoxic activity in vitro against tumor cells. This exptl. observation allowed us to confirm the importance of free N-H for the anticellular activity.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.