An efficient one-pot synthesis, characterization and antibacterial activity of novel chromeno-pyrimidine derivatives

Sulfoxidation of pyrimidine thioate derivatives and study their biological activities

In a quest to innovate biologically active molecules, the benzoylation of 4,6-dimethylpyrimidine-2-thiol hydrochloride (1) with benzoyl chloride derivatives was employed to produce a series of pyrimidine benzothioate derivatives (2-5). Subsequent sulfoxidation of these derivatives (2-5) using hydrogen peroxide and glacial acetic acid yielded a diverse array of pyrimidine sulfonyl methanone derivatives (6-9). In parallel, the sulfoxidation of pyrimidine sulfonothioates (10-12) yielded sulfonyl sulfonyl pyrimidines (13-15), originating from the condensation of compound 1 with sulfonyl chloride derivatives. The newly synthesized compounds underwent characterization via FT-IR, NMR, mass spectrometry, and elemental analyses. Biological screenings unveiled interesting properties: compounds 1 and 6 exhibited significant antimicrobial potency against S. epidermidis and S. haemolyticus, whereas compound 11 showed distinct insensitivity. Excitingly, compounds 12 and 6 showcased robust antioxidant activity by efficiently scavenging DPPH• radical, underscoring their potential in oxidative stress mitigation. Notably, compounds 10 and 12 displayed promising anti-tumor effects, with compound 12 demonstrating superior efficacy against the MCF-7 breast cancer cell line compared to compound 10. The study revealed a spectrum of biological activities across the synthesized derivatives, with modifications often resulting in diminished bioactivity compared to the parent compound 1. These findings shed light on the intricate relationship between chemical modifications and biological properties, offering valuable insights for future drug discovery endeavors.

The link between relative stability constant of DNA- and BSA-chromenopyrimidine complexes and cytotoxicity towards human breast cancer cells (MCF-7)

In this study, we synthesized and characterized ten chromenopyrimidine derivatives using analytical and spectroscopic methods. Studies on DNA and albumin binding affinity, as well as cytotoxicity tests on human breast cancer (MCF-7) cells, of the chromenopyrimidines, were conducted. The natural logarithm of the relative stability constant of DNA- and BSA-chromenopyrimidine complexes [ln(K_DNA/K_BSA)] was used as a criterion for selecting compounds for cytotoxicity studies. We found that ln(K_DNA/K_BSA) was inversely related to IC₅₀ values of the compounds in MCF-7 cells. The antiproliferative effects of the compounds were found to induce apoptosis in MCF-7 cells, which is a desired mechanism of cell death. Correlations between the DNA and albumin binding affinities of chromenopyrimidines were established. We propose that this relationship approach can, for a given set of compounds, assist in predicting the cytotoxicity of potential drug candidates towards MCF-7 cells based on their experimentally determined CT-DNA and BSA binding affinities.

Synthesis, characterization, thermal behavior, and antitumor activities of an Ag(I) complex based on 4-(2-hydroxyphenyl)-2-methylpyrimidine

A new Ag(I) coordination complex, Ag(C11H10N2O)2·NO3 (C11H10N2O = 4-(2-hydroxyphenyl)-2-methylpyrimidine) is successfully synthesized and characterized by infrared spectroscopy, elemental analysis, and single-crystal X-ray diffraction analysis. This complex features a three-dimensional framework consisting of hydrogen bonds, π–π stacking interactions, coordination interactions, and electrostatic interactions. Moreover, the thermal stability and non-isothermal thermal decomposition reaction kinetics of the complex are well investigated by the methods of Kissinger and Ozawa. Finally, the antitumor ability of the complex is evaluated against human lung cancer cells (NCI-H460), human hepatocellular cancer cells (HepG2), and human breast cancer cells (MCF7). The complex exhibits potent antitumor activities against HepG2 and MCF7 cancer cells.

Insights into the recent progress in the medicinal chemistry of pyranopyrimidine analogs

Heterocycles containing the pyranopyrimidine motif have attracted the interest of researchers in recent decades due to their ability to synthesize and explore at a large scale to explore the biological diversity. Therefore, this review highlights the biological characteristics and synthetic approaches adopted to prepare pyranopyrimidine analogs in the last five years. Several novel preparation procedures have been summarized to synthesize these compounds using ionic, basic, or nanocatalysts or catalyst-free conditions to obtain these compounds in good yields. Pyranopyrimidines could also be used as ligands in the preparation of metal complexes with increased biological potency. The different sections include the antimicrobial, antitubercular, antimalarial, antiviral "SARS-CoV-2 inhibitors", antidiabetic, antitumor, cytotoxic, antiinflammatory, antioxidant, anticoagulant, urease inhibitory activities, and tyrosine inhibitors. The results are discussed based on the structure-activity relationships (SARs) and the mechanism of action.

Microwave Assisted Synthesis, Crystal Structure and Hirshfeld Surface Analysis of Some 2-Formimidate-3-carbonitrile Derivatives Bearing 4H-Pyran and Dihydropyridine Moieties

Two 4H-pyran- and four dihydropyridine-based 2-formimidate-3-carbonitrile derivatives were synthesized via the conventional solvothermal and microwave radiation methods. The use of the latter technique led to the formation of the desired products in the order of minutes as compared to the former. The formation of the 2-formimidate-3-carbonitrile derivatives was confirmed using spectroscopic techniques whilst the molecular geometry and intermolecular interactions were investigated using single-crystal X-ray diffraction. The formimidate functional group was found to adopt an E configuration in all compounds and this coincides with those of closely related compounds on the Cambridge Structural Database (CSD). Classical but weak intermolecular C—H…O, C—H…N and C—H…π hydrogen bonds were observed in the crystal lattice. According to the Hirshfeld surface analysis, the C—H…π hydrogen bonds contributed the most towards the Hirshfeld surface (14.3–23.9%) than the other two hydrogen bonding types (9.6–12.7%).

Synthesis and Biological Evaluation of 3-cyano-4H-chromene Derivatives Bearing Carbamate Functionality

Background:

2-Aminochromene derivatives display important pharmacological properties, including mainly antibiotic and anticancer activities.

Objective:

The study aims to synthesize new chromene derivatives via a new approach using Grignard reagents, for the evaluation of their antibiotic and antifungal properties.

Method:

A series of novel 3-cyano-4-aminochromene derivatives bearing alkyl substituents at the 4-position was prepared for biological evaluation.

Results:

These compounds were obtained by the addition of various Grignard reagents into Nethoxycarbonyl- 3-cyanoiminocoumarines in moderate to good yields (72-96%). The reaction is completely regioselective. The new chromene derivatives were screened for their in vitro antimicrobial activities against a panel of six bacterial and three fungal strains using agar dilution method.

Conclusion:

The antibacterial activity of the chromene derivatives was more pronounced on Gram-positive bacteria than on Gram-negative bacteria with a significant activity observed against Staphylococcus aureus. An interesting antifungal activity against Fusarium sp. and Fusarium oxysporum was also noticed.

Synthesis of dibenzothiazepine analogues by one-pot S-arylation and intramolecular cyclization of diaryl sulfides and evaluation of antibacterial properties

Dibenzothiazepine analogues containing lactam, amidine and imine moieties were prepared from 2-aminophenyl disulfides via one-pot S-arylation. The S-arylation involved cleavage of an S-S bond of disulfides and SNAr reaction in aqueous ammonia solution of L-cysteine to afford diaryl sulfides. Dibenzothiazepine analogues having lactam and amidine moieties were obtained by cyclization of the corresponding diaryl sulfides under acidic conditions. One-pot S-arylation of 2-bromo-5-nitrobenzaldehyde gave dibenzothiazepine analogues with an imine moiety in one step through intramolecular cyclization. Compounds with antibacterial activities against Staphylococcus aureus and Escherichia coli were obtained.