Structural Characterization and Antimicrobial Activities of 7H-Benzo[h]chromeno[2,3-d]pyrimidine and 14H-Benzo[h]chromeno[3,2-e][1,2,4]triazolo[1,5-c] pyrimidine Derivatives

Base-Promoted Tandem Cyclization of 2-(Indol-3-yl)naphthoquinones with Benzamidines toward Polysubstituted Pyrimido[4,5-b]indoles

A novel and unique approach for the construction of polysubstituted pyrimido[4,5-b]indoles from 2-(indol-3-yl)naphthoquinones and benzamidines is described. Our strategy, promoted by an inorganic base, involves the ring opening and recyclization of naphthoquinone and produces three nitrogen heterocyclic rings via multiple C-N bond formations in one pot under transition-metal-free conditions.

Targeted potent antimicrobial and antitumor oxygen-heterocyclic-based pyran analogues: synthesis and computational studies

The process of creating a series of 3-amino-1-aryl-8-methoxy-1H-benzo[f]chromene-2-carbonitriles (4a-q) involved reacting 6-methoxynaphthalen-2-ol (1), the appropriate aromatic aldehydes (2a-q), and malononitrile (3) in an absolute ethanol/piperidine solution under Ultrasonic irradiation. However, the attempt to create 3-amino-1-aryl-1H-benzo[f]chromene-2,8-dicarbonitrile (6a, d, e) was unsuccessful when 6-cyanonaphthalen-2-ol (5) was stirred at room temperature, reflux, Microwave irradiation, or Ultrasonic irradiation. In addition, the target molecules were screened against Staphylococcus aureus (MRSA), Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Escherichia coli and Klebsiella pneumonia, as well as a panel of three human cancer cells lines such as MCF-7, HCT-116, HepG-2 and two normal cell lines HFL-1 and WI-38. The obtained results confirmed that the pyran derivatives (4 m, i, k) which have a double chlorine at 3,4/2,3/2,5-positions, a single halogen atom 3-Cl/4-Br (4c, e) and a double bromine at 3,5-positions with a single methoxy group at 2-position (4n), of phenyl ring, and, to a lesser extent, other pyran derivatives with monoihalogenated (4a, b, d, f), dihalogenated (4 g, h, j, l) or trisubstituent phenyl ring (4o, p, q). Furthermore, compounds 4b-e, g, i, j, m, and n showed negligible activity against the two normal cell lines, HFL-1 and WI-38. Moreover, compound 4 g exhibited the strongest antimicrobial activity among the other pyran derivatives (4a-f, g-q) when compared to Ciprofloxacin. The MIC was assessed and screened for compound 4 g, revealing bactericidal effects. Lastly, SAR and molecular docking were studied.

Design, synthesis and bioactivity study on oxygen-heterocyclic-based pyran analogues as effective P-glycoprotein-mediated multidrug resistance in MCF-7/ADR cell

P-glycoprotein (P-gp) imparts multi-drug resistance (MDR) on the cancers cell and malignant tumor clinical therapeutics. We report a class of newly designed and synthesized oxygen-heterocyclic-based pyran analogues (4a-l) bearing different aryl/hetaryl-substituted at the 1-postion were synthesized, aiming to impede the P-gp function. These compounds (4a-l) have been tested against cancerous PC-3, SKOV-3, HeLa, and MCF-7/ADR cell lines as well as non-cancerous HFL-1 and WI-38 cell lines to determine their anti-proliferative potency.The findings demonstrated the superior potency of 4a-c with 4-F, 2-Cl, and 3-Cl derivatives and 4h,g with 4-NO2, 4-MeO derivatives against PC-3, SKOV-3, HeLa, and MCF-7/ADR cell lines.Compounds 4a-c were tested for P-gp inhibition and demonstrated significant vigour against MCF-7/ADR cells with IC50 = 5.0-10.7 μM. The Rho123 accumulation assay showed that compounds 4a-c adequately inhibited P-gp function, as predicted. Furthermore, 4a or 4b administration resulted in MCF-7/ADR cell accumulation in the S phase, while compound 4c induced apoptosis by causing cell cycle arrest at G2/M. The molecular docking was applied to understand the likely modes of action and guide us in the rational design of more potent analogs. The investigate derivatives showed their good binding potential for p-gp active site with excellent docking scores and interactions. Finally, the majority of investigated derivatives 4a-c derivatives showed high oral bioavailability, but they did not cross the blood-brain barrier. These results suggest that they have favorable pharmacokinetic properties. Therefore, these compounds could serve as leads for designing more potent and stable drugs in the future.

An assessment of EGFR and HER2 inhibitors with structure activity relationship of fused pyrimidine derivatives for breast cancer: a brief review

Epidermal growth factor receptor (EGFR) and its subtype human epidermal growth factor receptor 2 (HER2) gets activated when its endogenous ligand(s) bind to its ATP binding site of target receptors. In breast cancer (BC), EGFR and HER2 are two proteins are overexpressed which leads to overexpression of cells proliferation and decreases cell death/apoptosis. Pyrimidine is one of the most widely studied heterocyclic scaffolds for EGFR as well as HER2 inhibition. We gather some remarkable results for fused-pyrimidine derivatives on various cancerous cell lines (in-vitro) and animal (in-vivo) evaluation to highlight their potency. The heterocyclic (five, six-membered, etc.) moieties which are coupled with pyrimidine moiety are potent against EGFR and HER2 inhibitions. Hence structure-activity relationship (SAR) plays important role in study of heterocyclic moiety along pyrimidine and effects of substituents, groups for increase or decrease in the cancerous activity and toxicity. By thoughtful of fused pyrimidines SAR study, it facilitates in receiving excellent overview of the compounds by concerning of efficacy and potential summary for future EGFR inhibitors. Furthermore, we studied the in-silico interactions of synthesized compounds to evaluate binding affinity towards the key amino acids..Communicated by Ramaswamy H. Sarma.

Synthetic Methods for Various Chromeno-fused Heterocycles and their Potential as Antimicrobial Agents

Chromenes are a significant family of heterocyclic chemicals that have a wide range of biological applications, a simple chemical structure, and only mildly undesirable side effects. The synthesis of a wide range of chromene analogs that displayed unexpected behaviors via numerous mechanisms was investigated by a number of different research teams, which led to the discovery of multiple pathways for their synthesis. In addition, different chromene-fused heterocycles exhibit a wide variety of fascinating biological actions, including those that are anticancer, anticonvulsant, antibacterial, anticholinesterase, antituberculosis, and anti-diabetic. In light of this, the purpose of this study is to highlight the many synthesis techniques and antibacterial activity associated with chromene-fused heterocyclic compounds. Moreover, such research can open avenues for exploring other therapeutic applications of these compounds in various disease areas, as their biological activities extend beyond antibacterial effects.

Discovery of benzochromene derivatives first example with dual cytotoxic activity against the resistant cancer cell MCF-7/ADR and inhibitory effect of the P-glycoprotein expression levels

A series of 1H-benzo[f]chromene moieties (4a-z) were synthesised under Ultrasonic irradiation and confirmed with spectral analyses. Derivative 4i solely possessed an X-ray single crystal. The anti-proliferative efficacy of the desired molecules has been explored against three cancer cells: MCF-7, HCT-116, and HepG-2 with the cytotoxically active derivatives screened against MCF-7/ADR and normal cells HFL-1 and WI-38. Furthermore, compounds 4b-d, 4k, 4n, 4q, and 4w, which possessed good potency against MCF-7/ADR, were tested as permeability glycoprotein (P-glycoprotein [P-gp]) expression inhibitors. The attained data confirmed that 4b-d, 4q, and 4w exhibited strong expression inhibition against the P-gp alongside its cytotoxic effect on MCF-7/ADR. The western blot results and Rho123 accumulation assays showed that compounds 4b-d, 4q, and 4w effectively inhibited the P-gp expression and efflux function. Meanwhile, 4b-d, 4q, and 4w induced apoptosis and accumulation of the treated MCF-7/ADR cells in the G1 phase and 4k and 4n in the S phase of the cell cycle.

Copper-Catalyzed Synthesis of 3-Aryl-9H-imidazo[1,5-a]indol-9-ones Using Oxygen as the Sole Oxidant

A three-component strategy was developed for 3-phenyl-9H-imidazo[1,5-a]indol-9-one preparation from indole-2-carboxaldehydes, aromatic aldehydes, and ammonium acetate under copper catalysis conditions. In this process, a new five-membered ring was formed and the C3 position in the indole substrate was selectively oxidized into a ketone skeleton using oxygen as the sole oxidant and ammonium acetate as the nitrogen source. Furthermore, same products also could be achieved from indole-2-carboxaldehydes and benzyl amines under similar reaction conditions.

Synthesis of 9-Hydroxy-1H-Benzo[f]chromene Derivatives with Effective Cytotoxic Activity on MCF7/ADR, P-Glycoprotein Inhibitors, Cell Cycle Arrest and Apoptosis Effects

β-Enaminonitriles bearing 9-hydroxy-1H-benzo[f]chromene moiety was synthesized. The targeted compounds were evaluated for their anti-proliferative activity against three human tumor cell lines, PC-3, SKOV-3 and HeLa, and the active cytotoxic compounds were further evaluated against cancer cells, MCF-7/ADR, and two normal cell lines, HFL-1 and WI-38. Few compounds were assigned to be the most potent derivatives against PC-3, SKOV-3 and HeLa cell lines in comparison with Vinblastine and Doxorubicin. Several compounds possessed a relatively good potency against MCF-7/ADR cells as compared with Doxorubicin and were tested as a P-gp inhibitor. Moreover, the halogenated substituents, 2,4-F₂, 2,3-Cl₂, 2,5-Cl₂ and 3,4-Cl_2; have good potency against P-gp-mediated MDR in MCF-7/ADR as compared with Doxorubicin. Meanwhile, Rho123 accumulation assays revealed that few compounds effectively inhibited P-pg and efflux function. In addition, certain derivatives induced apoptosis and an accumulation of the treated MCF-7/ADR cells in the G1, S and G1/S phases.

Acid-controlled multicomponent selective synthesis of 2,4,6-triaryl pyridines and pyrimidines by using hexamethyldisilazane as a nitrogen source under microwave irradiation

An efficient and general protocol for the synthesis of functionalized 2,4,6-triaryl pyridines and pyrimidines was developed from commercially available aromatic ketones, aldehydes and hexamethyldisilazane (HMDS) as a nitrogen source under microwave irradiation. In this multicomponent synthetic route, Lewis acids play an important role in selectively synthesizing six-membered heterocycles, including pyridines (1N) and pyrimidines (2N), by involving [2 + 1 + 2 + 1] or [2 + 1 + 1 + 1 + 1] annulated processes.

The Crystal Structure of 3-Amino-1-(4-Chlorophenyl)-9-Methoxy-1H-Benzo[f]Chromene-2-Carbonitrile: Antimicrobial Activity and Docking Studies

Compound 3-amino-1-(4-chlorophenyl)-9-methoxy-1H-benzo[f]chromene-2-carbonitrile (4), was synthesized via the reaction of 7-methoxynaphthalen-2-ol (1), 4-chlorobenzaldehyde (2), and malononitrile (3) in an ethanolic piperidine solution under microwave irradiation. The synthesized pyran derivative 4 was asserted through spectral data and X-ray diffraction. The molecular structure of compound 4 was established unambiguously through the single crystal X-ray measurements and crystallized in the Triclinic, P-1, a = 8.7171 (4) Å, b = 10.9509 (5) Å, c = 19.5853 (9) Å, α = 78.249 (2)°, β = 89.000 (2)°, γ = 70.054 (2)°, V = 1717.88 (14) Å3, Z = 4. The target molecule has been screened for antibacterial and antifungal functionality. Compound 4 exhibited favorable antimicrobial activities that resembled the reference antimicrobial agents with an IZ range of 16–26 mm. In addition, MIC, MBC, and MFC were assessed and screened for molecule 4, revealing bactericidal and fungicidal effects. Lastly, a molecular docking analysis was addressed and conducted for this desired molecule.

A Review on Fused Pyrimidine Systems as EGFR Inhibitors and Their Structure–Activity Relationship

Epidermal growth factor receptor (EGFR) belongs to the family of tyrosine kinase that is activated when a specific ligand binds to it. The EGFR plays a vital role in the cellular proliferation process, differentiation, and apoptosis. In the case of cancer, EGFR undergoes uncontrolled auto-phosphorylation that results in increased cellular proliferation and decreased apoptosis, causing cancer promotion. From the literature, it shows that pyrimidine is one of the most commonly studied heterocycles for its antiproliferative activity against EGFR inhibition. The authors have collated some interesting results in the heterocycle-fused pyrimidines that have been studied using different cell lines (sensitive and mutational) and in animal models to determine their activity and potency. It is quite clear that the fused systems are highly effective in inhibiting EGFR activity in cancer cells. Therefore, the structure–activity relationship (SAR) comes into play in determining the nature of the heterocycle and the substituents that are responsible for the increased activity and toxicity. Understanding the SAR of heterocycle-fused pyrimidines will help in getting a better overview of the molecules concerning their activity and potency profile as future EGFR inhibitors.

The Crystal Structure of 2-Amino-4-(2,3-Dichlorophenyl)-6-Methoxy-4H-Benzo[h]chromene-3-Carbonitrile: Antitumor and Tyrosine Kinase Receptor Inhibition Mechanism Studies

The target compound, 2-amino-4-(2,3-dichlorophenyl)-6-methoxy-4H-benzo[h]chromene -3-carbonitrile (4), was synthesized via the reaction of 4-methoxynaphthalen-1-ol (1), 2,3-dichlorobenzaldehyde (2), and malononitrile (3) in an ethanolic piperidine solution under microwave irradiation. The synthesized β-enaminonitrile derivative (4) was characterized by spectral data and X-ray diffraction. The in vitro anti-proliferative profile was conducted against five cancer cell lines and was assessed for compound 4, which revealed strong and selective cytotoxic potency. This derivative showed promising inhibition efficacy against the EGFR and VEGFR-2 kinases in comparison to Sorafenib as a reference inhibitor. Lastly, the docking analysis into the EGFR and VEGFR-2 active sites was performed to clarify our biological findings.

Three-Component Synthesis of 2-Amino-3-cyano-4H-chromenes, In Silico Analysis of Their Pharmacological Profile, and In Vitro Anticancer and Antifungal Testing

Chromenes are compounds that may be useful for inhibiting topoisomerase and cytochrome, enzymes involved in the growth of cancer and fungal cells, respectively. The aim of this study was to synthesize a series of some novel 2-amino-3-cyano-4-aryl-6,7-methylendioxy-4H-chromenes 4a-o and 2-amino-3-cyano-5,7-dimethoxy-4-aryl-4H-chromenes 6a-h by a three-component reaction, and test these derivatives for anticancer and antifungal activity. Compounds 4a and 4b were more active than cisplatin (9) and topotecan (7) in SK-LU-1 cells, and more active than 9 in PC-3 cells. An evaluation was also made of the series of compounds 4 and 6 as potential antifungal agents against six Candida strains, finding their MIC₅₀ to be less than or equal to that of fluconazole (8). Molecular docking studies are herein reported, for the interaction of 4 and 6 with topoisomerase IB and the active site of CYP51 of Candida spp. Compounds 4a-o and 6a-h interacted in a similar way as 7 with key amino acids of the active site of topoisomerase IB and showed better binding energy than 8 at the active site of CYP51. Hence, 4a-o and 6a-h are good candidates for further research, having demonstrated their dual inhibition of enzymes that participate in the growth of cancer and fungal cells.

Targeted potent antimicrobial benzochromene-based analogues: Synthesis, computational studies, and inhibitory effect against 14α-Demethylase and DNA Gyrase

7H-Benzo[7,8]chromeno[2,3-d]pyrimidin-9(8H)-amine (6a,b) have been synthesized via hydrazinolysis of the imidates (5a,b). Polysubstituted chromenotriazolopyrimidine (7a-j), (12a,b) and Schiff base (8a,b) derivatives have also been prepared. The new heterocyclic derivatives were affirmed by spectral data. The target compounds have been screened for antibacterial and antifungal activity. Compounds 6a,b and 7a-c, g,h displayed the most favorable antimicrobial activities in resemblance to the reference antimicrobial agents by IZ range over 24 mm. In addition, MIC, MBC and MFC were also tested and screen for most active compound 6a by 6.25 µg/mL showing bactericidal effect. SAR study revealed that the antimicrobial vitality of the target compounds was safely influenced by the lipophilicity substituents and the calculated log P value. The potent compounds were subjected into in vitro enzyme screening (14α-Demethylase and DNA Gyrase) against both interesting targets and showed good inhibitory profile. Molecular modeling analyses were introduced and discussed focusing on the docking of active compounds into two essential targets, and their ADMET properties were studied.