Synthesis, β-haematin inhibition, and in vitro antimalarial testing of isocryptolepine analogues: SAR study of indolo[3,2-c]quinolines with various substituents at C2, C6, and N11
摘要:
A series of indolo[3,2-c]quinolines were synthesized by modifying the side chains of the omega-aminoalkylamines at the C6 position and introducing substituents at the C2 position, such as F, Cl, Br, Me, MeO and NO2, and a methyl group at the N11 position for an SAR study. The in vitro antiplasmodial activities of the derivative agents against two different strains (CQS: NF54 and CQR: K1) and the cytotoxic activity against normal L6 cells were evaluated. The test results showed that compounds 6k and 6l containing the branched methyl groups of 3-aminopropylamino at C6 with a Cl atom at C2 exhibited a very low cytotoxicity with IC50 values above 4000 nM, high antimalarial activities with IC50 values of about 11 nM for CQS (NF54), IC50 values of about 17 nM for CQR (K1), and RI resistance indices of 1.6. Furthermore, the compounds were tested for beta-haematic inhibition, and QSAR revealed an interesting linear correlation between the biological activity of CQS (NF54) and three contributing factors, namely solubility, hydrophilic surface area, and beta-haematin inhibition for this series. In vivo testing of 6l showed a reduction in parasitaemia on day 4 with an activity of 38%. (C) 2014 Elsevier Ltd. All rights reserved.
Synthesis, β-haematin inhibition, and in vitro antimalarial testing of isocryptolepine analogues: SAR study of indolo[3,2-c]quinolines with various substituents at C2, C6, and N11
摘要:
A series of indolo[3,2-c]quinolines were synthesized by modifying the side chains of the omega-aminoalkylamines at the C6 position and introducing substituents at the C2 position, such as F, Cl, Br, Me, MeO and NO2, and a methyl group at the N11 position for an SAR study. The in vitro antiplasmodial activities of the derivative agents against two different strains (CQS: NF54 and CQR: K1) and the cytotoxic activity against normal L6 cells were evaluated. The test results showed that compounds 6k and 6l containing the branched methyl groups of 3-aminopropylamino at C6 with a Cl atom at C2 exhibited a very low cytotoxicity with IC50 values above 4000 nM, high antimalarial activities with IC50 values of about 11 nM for CQS (NF54), IC50 values of about 17 nM for CQR (K1), and RI resistance indices of 1.6. Furthermore, the compounds were tested for beta-haematic inhibition, and QSAR revealed an interesting linear correlation between the biological activity of CQS (NF54) and three contributing factors, namely solubility, hydrophilic surface area, and beta-haematin inhibition for this series. In vivo testing of 6l showed a reduction in parasitaemia on day 4 with an activity of 38%. (C) 2014 Elsevier Ltd. All rights reserved.
A series of 6-amino-11H- indolo[3,2-c]quinoline derivatives with various substituents on the quinoline ring were synthesized. A methyl group introduced to N-11 of the intermediate 4 to elaborate novel analog 7. The cytotoxic effect of these 6-amino-substituted 11H- and 11-methyl-indolo[3,2-c]quinoline derivatives in vitro were tested against MV4-11 (human leukemia), A549 (non-small cell lung cancer) and HCT116 (colon cancer) and BALB/3T3 (normal murine fibroblasts). All the N-11 methylated compounds significantly increased the cytotoxicity. Compound 7p was most active with the IC50 value of 0.052 mu M against the MV4-11 cell line, and also exhibited a selective activity against A549, HCT116 and BALB/3T3 cell line, with the respective IC50 values of 0.112, 0.007 and 0.083 mu M, which were higher or comparable to those of the anticancer drug doxorubicin HCl. The binding constants of 5g and 7h to salmon fish sperm DNA were also evaluated using UV-vis absorption spectroscopy, indicating intercalation binding with constants of 1.05 x 10(6) L/mol and 4.84 x 10(6) L/mol. (C) 2014 Elsevier Masson SAS. All rights reserved.