Design, synthesis, molecular modeling, and biological evaluation of novel α-aminophosphonates based quinazolinone moiety as potential anticancer agents: DFT, NBO and vibrational studies

Green Synthetic and Pharmacological Developments in the Hybrid Quinazolinone Moiety: An Updated Review

Bicyclic quinazolinone constitutes an important class of organic framework enveloping numerous biological properties which enthused organic and medicinal chemists to explore green synthetic strategies for the construction of quinazolinone hybrids with significantly improved pharmacodynamics and pharmacokinetic profiles. In this perspective, the present review summarizes the most recent green synthetic strategies, biological properties, structure-activity relationship, and molecular docking studies of the 4-quinazolinone-based scaffold. This review provides deeper insight into the hit-to-lead synthesis of quinazolinone derivatives in the development of clinically important therapeutic candidates.

6-Bromo quinazoline derivatives as cytotoxic agents: design, synthesis, molecular docking and MD simulation

Based on unselectively, several side effects and drug resistance of available anticancer agents, the development and research for novel anticancer agents is necessary. In this study, a new series of quinazoline-4(3H)-one derivatives having a thiol group at position 2 of the quinazoline ring (8a-8 h) were designed and synthesized as potential anticancer agents. The Chemical structures of all compounds were characterized by 1H-NMR, 13C-NMR, and Mass spectroscopy. The antiproliferative activity of all derivatives were determined against two cancer cell lines (MCF-7 and SW480) and one normal cell lines (MRC-5) by the MTT method. Cisplatin, Erlotinib and Doxorubicin were used as positive controls. The results of in vitro screening showed that 8a with an aliphatic linker to SH group was the most potent compound with IC50 values of 15.85 ± 3.32 and 17.85 ± 0.92 µM against MCF-7 and SW480 cell lines, respectively. 8a indicated significantly better potency compared to Erlotinib in the MCF-7 cell line. The cytotoxic results obtained from testing compound 8a on the normal cell line, revealing an IC50 value of 84.20 ± 1.72 µM, provide compelling evidence of its selectivity in distinguishing between tumorigenic and non-tumorigenic cell lines. Structure-activity relationship indicated that the variation in the anticancer activities of quinazoline-4(3H)-one derivatives was affected by different substitutions on the SH position. Molecular docking and MD simulation were carried out for consideration of the binding affinity of compounds against EGFR and EGFR-mutated. The binding energy of compounds 8a and 8c were calculated at -6.7 and - 5.3 kcal.mol- 1, respectively. Compounds 8a and 8c were found to establish hydrogen bonds and some other important interactions with key residue. The DFT analysis was also performed at the B3LYP/6-31 + G(d, p) level for compounds 8a, 8c and Erlotinib. Compound 8a was thermodynamically more stable than 8c. Also, the calculated theoretical and experimental data for the IR spectrum were in agreement. The obtained results delineated that the 8a can be considered an appropriate pharmacophore to develop as an anti-proliferative agent.

Design, synthesis, docking, and antiviral evaluation of some novel pyrimidinone-based α-aminophosphonates as potent H1N1 and HCoV-229E inhibitors

Dialkyl/aryl aminophosphonates, 3a-g and 4a-e were synthesized using the LiClO4 catalyzed Kabachnic Fields-type reaction straightforwardly and efficiently. The synthesized phosphonates structures were characterized using elemental analyses, FT-IR, 1H NMR, 13C NMR, and MS spectroscopy. The new compounds were subjected to in-silico molecular docking simulations to evaluate their potential inhibition against Influenza A Neuraminidase and RNA-dependent RNA polymerase of human coronavirus 229E. Subsequently, the compounds were further tested in vitro using a cytopathic inhibition assay to assess their antiviral activity against both human Influenza (H1N1) and human coronavirus (HCoV-229E). Diphenyl ((2-(5-cyano-6-oxo-4-phenyl-1,6-dihydropyrimidin-2-yl) hydrazinyl) (furan-2-yl) methyl) phosphonate (3f) and diethyl ((2-(5-cyano-6-oxo-4-phenyl-1,6-dihydropyrimidin-2-yl) hydrazinyl) (1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl) methyl) phosphonate (4e) were demonstrated direct inhibition activity against Influenza A Neuraminidase and RNA-dependent RNA polymerase. This was supported by their highly favorable binding energies in-silico, with top-ranked values of -12.5 kcal/mol and -14.2 kcal/mol for compound (3f), and -13.5 kcal/mol and -9.89 kcal/mol for compound (4e). Moreover, they also displayed notable antiviral efficacy in vitro against both viruses. These compounds demonstrated significant antiviral activity, as evidenced by selectivity indices (SI) of 101.7 and 51.8, respectively against H1N1, and 24.5 and 5.1 against HCoV-229E, respectively.

Anticancer activity, DFT study, ADMET prediction, and molecular docking of novel α-sulfamidophosphonates

A series of novel α-sulfamidophosphonate derivatives (3a-3 g) were synthesized and evaluated for anticancer activity against different human cancer cell lines (PRI, K562, and JURKAT). The antitumor activity of all compounds using the MTT test remains moderate compared to the standard drug chlorambucil. Compounds 3c and 3 g were found to be more active anticancer agent against PRI and K562 cells with IC50 value 0.056-0.097 and 0.182-0.133 mM, respectively. Molecular docking study related to binding affinity and binding mode analysis showed that synthesized compounds had potential to inhibit glutamate carboxypeptidase II (GCPII). Furthermore, computational analysis was performed through Density Functional Theory (DFT) utilizing the B3LYP 6-31 G (d, p) basis set and the theoretical results were correlated with experimental data. The ADME/toxicity analyses carried out by Swiss ADME and OSIRIS software show that all synthesized molecules exhibited good pharmacokinetics, bioavailability, and had no toxicity profile.

Synthesis, Docking, and DFT Studies on Novel Schiff Base Sulfonamide Analogues as Selective COX-1 Inhibitors with Anti-Platelet Aggregation Activity

Selective COX-1 inhibitors are preferential therapeutic targets for platelet aggregation and clotting responses. In this study, we examined the selective COX-1-inhibitory activities of four newly synthesized compounds, 10-13, along with their abilities to inhibit platelet aggregation against ADP and collagen. The target compounds 10-13 were synthesized using the conventional method, sonication, and microwave-assisted methods. Microanalytical and spectral data were utilized to elucidate the structures of the new compounds 10-13. Additionally, a spectral NMR experiment [NOESY] was conducted to emphasize the configuration around the double bond of the imine group C=N. The obtained results revealed no observed correlation between any of the neighboring protons, suggesting that the configuration at the C=N double bond is E. Biological results revealed that all the screened compounds 10-13 might serve as selective COX-1 inhibitors. They showed IC50 values ranging from 0.71 μM to 4.82 μM against COX-1 and IC50 values ranging from 9.26 μM to 15.24 μM against COX-2. Their COX-1 selectivity indices ranged between 2.87 and 18.69. These compounds show promise as promising anti-platelet aggregation agents. They effectively prevented platelet aggregation induced by ADP with IC50 values ranging from 0.11 μM to 0.37 μM, surpassing the standard aspirin with an IC50 value of 0.49 μM. Additionally, they inhibited the platelet aggregation induced by collagen with IC50 values ranging from 0.12 μM to 1.03 μM, demonstrating superior efficacy compared to aspirin, which has an IC50 value of 0.51 μM. In silico molecular modeling was performed for all the target compounds within the active sites of COX-1 and COX-2 to rationalize their selective inhibitory activities towards COX-1. It was found that the binding interactions of the designed compounds within the COX-1 active site had remained unaffected by the presence of celecoxib. Molecular modeling and DFT calculations using the B3LYP/6-31+G (d,p) level were performed to study the stability of E-forms with respect to Z-forms for the investigated compounds. A strong correlation was observed between the experimental observations and the quantum chemical descriptors.

Synthesis of Indole-Linked Thiadiazoles and their Anticancer Action against Triple-Negative Breast Cancer

With a lack of targeted therapy and significantly high metastasis, heterogeneity, and relapse rates, Triple-Negative Breast Cancer (TNBC) offers substantial treatment challenges and demands more chemotherapeutic interventions. In the present study, indole-endowed thiadiazole derivatives have been synthesized and screened for antiproliferative potency against the triple-negative breast cancer MDA-MB-231 cell line. Compound 4 h, possessing chlorophenyl moiety, displays the best anticancer potency (IC50: 0.43 μM) in the cell viability assay. The title compounds demonstrate substantial docking competency against the EGFR receptor (PDB ID: 3POZ), validating their in-vitro ant proliferative action. With a high docking score (-9.9 to -8.7 kcal/mol), the indole hybrids display significant binding propensity comparable to the co-crystallized ligand TAK-285 and occupy a similar strategic position in the active domain of the designated receptor. The quantum and electronic properties of the integrated templates are evaluated through DFT, and optimal values of the deduced global reactivity indices, such as energy gap, electronegativity, ionization potential, chemical potential, electrophilicity, etc., suggest their apt biochemical reactivity. The indole hybrids show near-appropriate pharmacokinetic efficacy and bioavailability in the in-silico studies, indicating their candidacy for potential drug usage. Promising in-vitro anticancer action and binding interfaces project indole conjugates as potential leads in addressing the TNBC dilemma.

Computational studies on potential new anti-Covid-19 agents with a multi-target mode of action

A compound that could inhibit multiple targets associated with SARS-CoV-2 infection would prove to be a drug of choice against the virus. Human receptor-ACE2, receptor binding domain (RBD) of SARS-CoV-2 S-protein, Papain-like protein of SARS-CoV-2 (PLpro), reverse transcriptase of SARS-CoV-2 (RdRp) were chosen for in silico study. A set of previously synthesized compounds (1-5) were docked into the active sites of the targets. Based on the docking score, ligand efficiency, binding free energy, and dissociation constants for a definite conformational position of the ligand, inhibitory potentials of the compounds were measured. The stability of the protein-ligand (P-L) complex was validated in silico by using molecular dynamics simulations using the YASARA suit. Moreover, the pharmacokinetic properties, FMO and NBO analysis were performed for ranking the potentiality of the compounds as drug. The geometry optimizations and electronic structures were investigated using DFT. As per the study, compound-5 has the best binding affinity against all four targets. Moreover, compounds 1, 3 and 5 are less toxic and can be considered for oral consumption.

Hydroxy- and Amino-Phosphonates and -Bisphosphonates: Synthetic Methods and Their Biological Applications

Phosphonates and bisphosphonates are stable analogs of phosphates and pyrophosphates that are characterized by one and two carbon–phosphorus bonds, respectively. Among the various phosphonates and bisphosphonates, hydroxy and amino substitutes are of interest as effective in medicinal and industrial chemistry. For example, hydroxy bisphosphonates have proven to be effective for the prevention of bone loss, especially in osteoporotic disease. On the other hand, different substitutions on the carbon atom connected to phosphorus have led to the synthesis of many different hydroxy- and amino-phosphonates and -bisphosphonates, each with its distinct physical, chemical, biological, therapeutic, and toxicological characteristics. Dialkyl or aryl esters of phosphonate and bisphosphonate compounds undergo the hydrolysis process readily and gave valuable materials with wide applications in pharmaceutical and agriculture. This review aims to demonstrate the ongoing preparation of various classes of hydroxy- and amino-phosphonates and -bisphosphonates. Furthermore, the current review summarizes and comprehensively describes articles on the biological applications of hydroxyl- and amino-phosphonates and -bisphosphonates from 2015 until today.

Selective electrophilic di- and mono-fluorinations for the synthesis of 4-difluoromethyl and 4-fluoromethyl quinazolin(thi)ones by Selectfluor-triggered multi-component reaction

A simple and efficient domino protocol for the selective synthesis of 4-difluoromethyl and 4-fluoromethyl quinazolin(thi)ones was established from readily available 2-aminoacetophenones and iso(thio)cyanates mediated by Selectfluor. The reaction outcomes are...

Molecular Iodine-Mediated Synthesis of 2-Azaanthraquinones from [3.3.3]Propellanes via a Metal-Free Rearrangement

A novel iodine-mediated rearrangement of heterocyclic [3.3.3]propellanes under green conditions is described. This metal-free transformation for the straightforward synthesis of substituted 2-azaanthraquinones proceeds via ring opening/dissociation of C–O and C–N bonds/intramolecular C(sp3)–C(sp3) bond formation/ring expansion/aza-ring closure/1,3-N to N alkyl migration. High atom-efficiency, synthetically useful yields, easily accessible starting materials, and mild reaction conditions are advantages of this process.

Synthesis of α-Aminophosphonates and Related Derivatives; the Last Decade of the Kabachnik-Fields Reaction

The Kabachnik-Fields reaction, comprising the condensation of an amine, oxo compound and a P-reagent (generally a >P(O)H species or trialkyl phosphite), still attracts interest due to the challenging synthetic procedures and the potential biological activity of the resulting α-aminophosphonic derivatives. Following the success of the first part (Molecules 2012, 17, 12821), here we summarize the synthetic developments in this field accumulated in the last decade. The procedures compiled include catalytic accomplishments as well as catalyst-free and/or solvent-free "greener" protocols. The products embrace α-aminophosphonates, α-aminophosphinates, and α-aminophosphine oxides along with different bis derivatives from the double phospha-Mannich approach. The newer developments of the aza-Pudovik reactions are also included.

Octahydroquinoxalin-2(1H)-One-Based Aminophosphonic Acids and Their Derivatives-Biological Activity Towards Cancer Cells

In the search for new antitumor agents, aminophosphonic acids and their derivatives based on octahydroquinoxalin-2(1H)-one scaffold were obtained and their cytotoxic properties and a mechanism of action were evaluated. Phosphonic acid and phosphonate moieties increased the antiproliferative activity in comparison to phenolic Mannich bases previously reported. Most of the obtained compounds revealed a strong antiproliferative effect against leukemia cell line (MV-4-11) with simultaneous low cytotoxicity against normal cell line (mouse fibroblasts-BALB/3T3). The most active compound was diphenyl-[(1R,6R)-3-oxo-2,5-diazabicyclo[4.4.0]dec-4-yl]phosphonate. Preliminary evaluation of the mechanism of action showed the proapoptotic effect associated with caspase 3/7 induction.

A comparison between observed and DFT calculations on structure of 5-(4-chlorophenyl)-2-amino-1,3,4-thiadiazole

The crystal and molecular structure of 5-(4-chlorophenyl)-2-amino-1,3,4-thiadiazole 3 was reported, which was characterized by various spectroscopic techniques (FT-IR, NMR and HRMS) and single-crystal X-ray diffraction. The crystal structure 3 (C₈H₆ClN₃S) crystallized in the orthorhombic space group Pna2₁ and the unit cell consisted of 8 asymmetric molecules. The unit cell parameters were a = 11.2027(2) Å, b = 7.6705(2) Å, c = 21.2166(6) Å, α = β = γ = 90°, V = 1823.15(8) ų, Z = 8. In addition, the structural geometry (bond lengths, bond angles, and torsion angles), the electronic properties of mono and dimeric forms of compound 3 were calculated by using the density functional theory (DFT) method at B3LYP level 6-31+ G(d,p), 6-31++ G(d,p) and 6-311+ G(d,p) basis sets in ground state. A good correlation was found (R² = 0.998) between the observed and theoretical vibrational frequencies. Frontier molecular orbitals (HOMO and LUMO) and Molecular Electrostatic Potential map of the compound was produced by using the optimized structures. The NBO analysis was suggested that the molecular system contains N-H…N hydrogen bonding, strong conjugative interactions and the molecule become more polarized owing to the movement of π-electron cloud from donor to acceptor. The calculated structural and geometrical results were in good rational agreement with the experimental X-ray crystal structure data of 1,3,4-thiadiazol-2-amine, 3. The compound 3 exhibited n→π* UV absorption peak of UV cutoff edge, and great magnitude of the first-order hyperpolarizability was observed. The obtained results suggest that compound 3 could have potential application as NLO material. Therefore, this study provides valuable insight experimentally and theoretically, for designing new chemical entities to meet the demands of specific applications.

A Simple Metal-Free Cyclization for the Synthesis of 4-Methylene-3-Substituted Quinazolinone and Quinazolinthione Derivatives: Experiment and Theory

A new series of 3-substituted 4-methylene-quinazolinthiones and 4-methylene-quinazolinones were synthesized in moderate to excellent yield through a simple reaction of 2-aminoacetophenones with isocyanates or isothiocyanates. The reaction shows good tolerance of many important functional groups in the presence of air and water under metal-free conditions. Only water is produced as a coproduct, rendering this “green” methodology a highly versatile and eco-friendly alternative to the existing methods for the construction of the quinazolinone/quinazolinthione framework. We have interpreted the reaction mechanism by use of quantum chemical calculations on the basis of state-of-the-art computational methods SMD-B3LYP-D3(BJ)/BS1//B3LYP/BS1.

Novel Phosphorylated Penta-1,4-dien-3-one Derivatives: Design, Synthesis, and Biological Activity

A series of novel phosphorylated penta-1,4-dien-3-one derivatives were designed and synthesized. The structures of all title compounds were determined by ¹H-NMR, ¹³C-NMR, ³¹P-NMR, and high-resolution mass spectrometry (HRMS). Bioassay results showed that several of the title compounds exhibited remarkable antibacterial and antiviral activities. Among these, compound 3g exhibited substantial antibacterial activity against Xanthomonas oryzae pv. Oryzae (Xoo), with a 50% effective concentration (EC₅₀) value of 8.6 μg/mL, which was significantly superior to bismerthiazol (BT) (58.8 µg/mL) and thiodiazole-copper (TC) (78.7 μg/mL). In addition, compound 3h showed remarkable protective activity against tobacco mosaic virus (TMV), with an EC₅₀ value of 104.2 μg/mL, which was superior to that of ningnanmycin (386.2 μg/mL). Furthermore, the microscale thermophoresis and molecular docking experiments on the interaction of compounds 3h and 3j with TMV coat protein (TMV CP) were also investigated. Compounds 3h and 3j bound to TMV CP with dissociation constants of 0.028 and 0.23 μmol/L, which were better than that of ningnanmycin (0.52 μmol/L). These results suggest that novel phosphorylated penta-1,4-dien-3-one derivatives may be considered as an activator for antibacterial and antiviral agents.