# Schiff Bases: Interesting Scaffolds with Promising Antitumoral Properties
## 2 Schiff Bases as Antiproliferative Agents
### Mono-Schiff Bases
(2020) synthesized and studied two Schiff bases (**54** and **55**) for different biological activities, among them the antitumor one, against MCF-7 human breast cancer cell line. The IC\({}_{50}\) values were 6.70, 2.20, and \(<\)0.1 mM for **54**; 1.00, 0.30, and 0.14 mM for **55** for 24, 48, and 72 h, respectively. The higher activity of compound containing 10-chloroanthracene **55** than that containing 8-hydroxyquinoline **54** was in agreement with theoretical calculations obtained by various spectroscopic analyses and single-crystal X-ray diffraction and Hirshfeld surface analysis and fingerprint plots of the two compounds. [PERSON] et al. (2020) [PERSON] et al. (2020) [PERSON] et al. (2020) [PERSON] et al. (2020) synthesized two Schiff bases (**56** and **57**) and evaluated their antiproliferative activity against MCF-7 cells, obtaining IC\({}_{50}\) values of 80.19 uM for compound **56** and 44.12 uM for compound **57** (doxorubicin: IC\({}_{50}\) = 2.05 uM). Molecular docking studies were also carried out against six different active sites [PERSON] et al. (2020) [PERSON] et al. (2020) [PERSON] et al. (2020) studied several Schiff bases containing a benzothiazole nucleus and studied the DNA binding interaction with pBR322 plasmid DNA by means of electrophoretic mobility shift assay [PERSON] et al. (2020). The anticancer study was performed using the MTT assay. Imine **58** showed 85.82% inhibition of MCF-7 cancer cell lines at a concentration of 200 ug/mL. It was less toxic to normal cells at the concentration required to produce the anticancer effect (IC\({}_{50}\) = 973 ug/mL). \begin{table}
\begin{tabular}{c c c} \hline \hline \(\text{LD}_{50}=16\) mg/kg. & [PERSON] et al., 2010 [50] \\ \(\text{LD}_{4}\) & 14 \\ (PHP) & \\ \hline \(\text{LD}_{50}=15.5\) mg/kg; maximum percentage cell growth inhibition = 93\% (\text{EAC}). & [PERSON] et al., 2010 [50] \\ \(\text{LC}_{50}=0.186\)\(\text{uM}\) (HeLa). & [PERSON] et al., 2011 [51] \\ \(\text{LC}_{50}=4.73\) (HeLa), 9.23 (MCF-7, metastatic). & [PERSON] et al., 2011 [52] \\ \(\text{LC}_{50}=3.24\)\(\text{uM}\) (HeLa), 15.27\(\text{uM}\) (MCF-7, metastatic). & [PERSON] et al., 2011 [52] \\ \(\text{LC}_{50}=1\)–10 mg/mL (HepG2, HCT-116 and MCF-7). & [PERSON] et al., 2011 [53] \\ \(\text{LC}_{50}=0.08\) mg/mL (HT-29 cell line). & [PERSON] et al., 2012 [54] \\ \ \begin{table}
\begin{tabular}{c c c} \hline \hline IC\({}_{50}\) = 50.12 \(\upmu\)M (KYSE 150), 158.49 \(\upmu\)M (KYSE30), 111.2 \(\upmu\)M (KYSE 270). & [PERSON] et al., 2013 [57] \\ \hline \hline \(\upmu\)M & IC\({}_{50}\) = 0.44 \(\upmu\)M (SK OV-3). & [PERSON] et al., 2013 [58] \\ \hline \(\upmu\)M & IC\({}_{50}\) = 0.09 nM (U937), IC\({}_{50}\) = 0.45 nM (GOTO), IC\({}_{50}\) = 0.64 nM (NB-1), & [PERSON] et al., 2013 [58] \\ \(\upmu\)M & IC\({}_{50}\) = 0.54 nM (HT1080). & [PERSON] et al., 2013 [58] \\ \hline \(\upmu\)M & IC\({}_{50}\) = 0.54 \(\upmu\)M (KB), IC\({}_{50}\) = 0.30 nM (CNS, SF-268), IC\({}_{50}\) = 0.43 nM (K-562), & [PERSON] et al., 2013 [58] \\ \(\upmu\)M & IC\({}_{50}\) = 0.09 nM (HepG2), IC\({}_{50}\) = 6.60 nM (NCI H460). & [PERSON] et al., 2013 [58] \\ \hline \(\upmu\)M & IC\({}_{50}\) = 6.20 \(\upmu\)M (HEPG2), IC\({}_{50}\) = 7 \(\upmu\)g/mL (MCF-7). & [PERSON] et al., 2015 [59] \\ \(\upmu\)M & IC\({}_{50}\) = 4.02 \(\upmu\)M (MCF-7). & [PERSON] et al., 2013 [60] \\ \(\upmu\)M & IC\({}_{50}\) = 7.55 \(\upmu\)M (MCF-7). & [PERSON] et al., 2013 [60] \\ \(\upmu\)M & IC\({}_{50}\) = 8.51 \(\upmu\)M (MCF-7). & [PERSON] et al., 2013 [60] \\ \(\upmu\)M & IC\({}_{50}\) = 38.73 \(\upmu\)M (L1210). & [PERSON] et al., 2013 [60] \\ \(\upmu\)M & IC\({}_{50}\) = 0.15 \(\upmu\)g/mL (potato disc). & [PERSON] et al., 2013 [61] \\ \(\upmu\)M & IC\({}_{50}\) = 0.15 \(\upmu\)g/mL (potato disc). & [PERSON] et al., 2013 [61] \\ \hline \hline \end{tabular}
\end{table} 
Table 1: \(Cont.\)  
\begin{table}
\begin{tabular}{c c c} \hline \hline \(\mathrm{IC_{50}}\) = 8.03 \(\mathrm{\SIUnitSymbolMicro g}\)/mL (potato disc).