Two novel norcantharidin acylamide acids (HL1=N-pyrimidine norcantharidin acylamide acid, C12H13N3O4; HL2=N-pyridine norcantharidin acylamide acid, C13H14N2O4) were synthesized by a reaction of norcantharidin(NCTD) with 2-aminopyrimidine and 2-aminopyridine, respectively. Their structures were characterized by elemental analysis, IR, UV and 1 H NMR. Fluorescence titration and viscosity measurements indicated that HL1, HL2 and HL3 (HL3=N-phenyl norcantharidin acylamide acid, C14H15NO4) can bind calf thymus DNA via partial intercalation. The liner Stern-Volmer quenching constant Ksv values for HL1, HL2 and HL3 were 2.05 × 104 L mol−1, 1.15 × 104 L mol−1 and 8.30×103 L mol−1, respectively. Two compounds containing heterocycle of HL1 and HL2 have been found to cleave pBR322 plasmid DNA at physiological pH and temperature. The test of antiproliferation activity showed that the compounds had moderate to strong antiproliferative ability against the tested cell lines except of HL3 against the SMMC7721 cell line. The results indicated that the heterocycle attached to the norcantharidin was favorable to antiproliferative activity. This result was consistent with the DNA binding experiment. <alternatives> [...] </alternatives>
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
SYNAT - “Interdisciplinary System for Interactive Scientific and Scientific-Technical Information”.