Synthesis and Evaluation of 2‑Substituted Quinazolin-4(3 H)‑ones as Potential Antileukemic Agents

Abstract

The increasing life expectancy and rising prevalence of cancer emphasize the need for innovative therapeutic strategies. Targeted therapies have revolutionized cancer treatment by offering greater specificity and reduced toxicity compared to traditional cytotoxic drugs. Acute leukemias, including acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML), remain aggressive malignancies with poor outcomes, particularly in elderly patients. Despite advancements, resistance to chemotherapy and adverse effects necessitate the discovery of novel antitumor compounds. Quinazolines, a versatile class of heterocyclic compounds, exhibit diverse biological activities, including anticancer properties. In this study, 20 derivatives of 2-substituted quinazolin-4-(3H)-ones were synthesized via condensation of 2-aminobenzamide with aldehydes in dimethyl sulfoxide. The compounds were characterized using IR, ¹H NMR, and ¹³C NMR spectroscopy. Biological evaluation revealed that compounds 6 and 17 exhibited potent cytotoxic effects against T cell ALL (jurkat cells) and AML of promyelocytic subtype (APL) NB4 cells, with compound 17 showing IC₅₀ values below 5 μM in both cell types. Compound 6 demonstrated selectivity for Jurkat cells. Further in vitro analyses, including apoptosis/cycle cell assays and pharmacokinetic predictions, confirmed their therapeutic potential. The data open new perspectives for "in vivo" studies concerning the application of quinazolin-4-(3H)-ones in treatment of acute leukemias of lymphoid and myeloid origins.

1

Drugs used in cancer treatment that have the quinazoline and quinazolin-4­(3H)-one rings.

2

Schematic representation of the reaction to obtain 2-substituted quinazolin-4­(3H)-ones.

3

Structures and yields of the 2-substituted quinazolin-4­(3H)-ones obtained.

4

Range of values observed in IR, ¹³C NMR and ¹H NMR spectra for the 2-substituted quinazolin-4-(3H)-ones.

5

Concentration- and time-dependent response curves for compounds 6 and 17 in Jurkat and NB4 cells. The Jurkat and NB4 leukemic cell lines were used to investigate the concentration-dependent response by MTT, and the 50% inhibitory concentration (IC₅₀) values are indicated for each cell line. The cells were treated with vehicle or with increasing concentrations of the compounds of interest for 24, 48, and 72 h. The results are expressed as a percentage in relation to the cells treated with vehicle and presented as a mean and standard deviation.

6

17 is highly effective at inducing apoptosis in Jurkat and NB4 cells. Apoptosis was measured by flow cytometry in Jurkat and NB4 cells treated with either vehicle or increasing concentrations of 6 or 17 (ranging from 0.6 to 10 μM) for 48 h. Representative dot plots are shown for each condition. The upper and lower right quadrants (Q2 plus Q3) cumulatively represent the apoptotic cell population (annexin V+ cells). Bar graphs show the mean ± SD of at least three independent experiments. The p-values and cell lines are indicated in the graphs; *p < 0.05, **p < 0.01, ***p < 0.0001; ANOVA with Bonferroni post-test.

7

Data expressed in these graphs are the results of 3 distinct experiments analyzed at 3 different times (12, 24, and 48 h) and both were subjected to ANOVA statistical analysis with Bonferroni post-test and the error bars are SD p < 0.05 for controls and p < 0.001 for the other bars.

8

Compounds 2, 6, 17 and 20 showed antileukemic activity against the Jurkat and NB4 cell lines. The drugs idelalisib, vincristine and doxorubicin were used for property prediction studies.