Nitrogen Containing Heterocycles as Anticancer Agents: A Medicinal Chemistry Perspective

Cancer is one of the major healthcare challenges across the globe. Several anticancer drugs are available on the market but they either lack specificity or have poor safety, severe side effects, and suffer from resistance. So, there is a dire need to develop safer and target-specific anticancer drugs. More than 85% of all physiologically active pharmaceuticals are heterocycles or contain at least one heteroatom. Nitrogen heterocycles constituting the most common heterocyclic framework. In this study, we have compiled the FDA approved heterocyclic drugs with nitrogen atoms and their pharmacological properties. Moreover, we have reported nitrogen containing heterocycles, including pyrimidine, quinolone, carbazole, pyridine, imidazole, benzimidazole, triazole, β-lactam, indole, pyrazole, quinazoline, quinoxaline, isatin, pyrrolo-benzodiazepines, and pyrido[2,3-d]pyrimidines, which are used in the treatment of different types of cancer, concurrently covering the biochemical mechanisms of action and cellular targets.

Novel Hydrazone Derivatives of 3-Bromopyruvate: Synthesis, Evaluation of the Cytotoxic Effects, Molecular Docking and ADME Studies

A series of 3-bromopyruvate (3-BP) derivatives were synthesized to develop new potent anticancer agents. The chemical structures of the compounds were characterized using FT-IR, ¹ H-, ¹³ C-NMR spectroscopy, and elemental analysis (CHN). Their cytotoxic activities were investigated against four cancer cell lines, including colon (SW1116), breast (MDA-MB-231), lung (A549), and liver (HepG2) cancer cell lines. Among the synthesized compounds, 3b showed promising cytotoxic activity compared to 3-BP, with IC₅₀ values of 16.3 μM, 19.1 μM, 27.8 μM, and 14.5 μM against A549, MDA-MB-231, SW1116 and, HepG2 cell lines, respectively. Furthermore, the effect of these compounds on MCF-10A (a normal breast cell lines) was investigated to determine their selectivity between tumorigenic and non-tumorigenic cells. Since the 3-BP inhibits hexokinase II (HK II), molecular docking of 3-BP derivatives was carried out using AutoDock 4.2. The binding energies of these derivatives were greater than 3-BP, indicating that they had a higher affinity for HK II. For validation of docking, a 40 ns MD simulation was performed. SwissADME was used to predict pharmacokinetics, drug-likeness, and ADME parameters of the screened compounds. The results demonstrated that these derivatives are suitable candidates for developing orally potent HK II inhibitors.

Antiproliferative activity and DNA binding studies of cyclometalated complexes of platinum(II) containing 2-vinylpyridine

The cytotoxic activity of four cyclometalated platinum(II) complexes [PtMe(vpy)(L)], containing 2-vinylpyridine (vpy) and the phosphine ligands (L) PMe₂Ph (1a), PPh₃ (1b), PMePh₂ (1c), and P(c-Hex)₃ (1d), were evaluated against human breast cancer (MDA-MB-231), human lung cancer (A549), human colon cancer (SW1116), and non-tumor epithelial breast (MCF-10 A) cell lines. The highest activity was found for 1c with IC₅₀ values of 21.10 µM, 23.36 µM, and 12.96 µM, compared to cisplatin, which was 10.12 µM, 47.57 µM, and 19.50 µM against the A549, SW1116, and MDA-MB-231 cell lines, respectively. 1a-d showed a higher selectivity index (SI) than cisplatin. Docking studies confirmed interaction to the DNA minor groove for all complexes. Genotoxicity studies on 1c showed interactions with the genomic content of malignant cells. Compared with cisplatin as a positive control, a slight shift was found in the electrophoresis mobility, which was utilized further to study the direct interaction of 1c with DNA.

Current status of carbazole hybrids as anticancer agents

The drug resistance and low specificity of current available chemotherapeutics to cancer cells are the main reasons responsible for the failure of cancer chemotherapy and remain dramatic challenges for cancer therapy, creating an urgent need to develop novel anticancer agents. Carbazole nucleus, widely distributed in nature, is a predominant feature of a vast array of biologically active compounds. Carbazole derivatives exhibited potential antiproliferative activity against different cancer cell lines by diverse mechanisms, inclusive of arrest cell cycle and induce apoptosis, and several anticancer agents are carbazole-based compounds. Thus, carbazole derivatives represent a fertile source for discovery of novel anticancer therapeutic agents. Over the past several years, a variety of carbazole hybrids have been developed as potential anticancer agents. The present review focuses on the recent progress, from 2016 until now, in knowledge on anticancer properties, structure-activity relationships and mechanisms of action of carbazole hybrids to provide a basis for development of relevant therapeutic agents.