Human Cell Line MCF-7 Research Articles

The Anti-proliferative Effect, Apoptotic Induction, and Cell Cycle Arrest of Tetra Halo Ruthenate Nanocomposites in Different Human Cancer Cell Lines.

Chemotherapy is the most common cancer treatment, and metallic anticancer compounds have generated increasing amounts of interest since the discovery of cisplatin. More recently, scientists have focused on ruthenium-based compounds as alternatives for platinum compounds, which seem like ideal therapeutic anticancer alternatives to platinum derivatives. The present study aims to assess whether one or more of three Ruthenium-based nanocomposites, namely Ru+Lysine+CTAB (RCTL), Ru+CTAB (RCT), and Ru+Lysine (RL) exhibit pronounced anti-proliferative properties against different cancer cells. Three Ruthenium nanocomposites have been synthesized by standard chemical methods and characterized by Dynamic light scattering (DLS) and Transmission electron microscopy (TEM). The cytotoxic effect of the three composites has been evaluated by MTT in-vitro assay for different human cancer cell lines, namely MCF7, HepG2, A549, and PC3 versus normal human skin cell line (BJ1). The molecular underlying mechanisms of cytotoxicity have been assessed via qRT-PCR for pro-apoptotic makers P53 and Casp-3, and anti-apoptotic marker Bcl-2 as well as flow cytometric analysis of the cell cycle. Among the 3 nanocomposites, RCTL gave the best sensitivity and cytotoxicity especially on HepG2 with IC50 0.55 µg/ml but was still toxic on normal cell line with dose <12.5 µg/ml. RCTL and RCT nanocomposites have demonstrated a significant increase in the expression of P53 and Casp-3 markers versus untreated controls, but a significant reduction in the expression of Bcl-2. There was a direct correlation between the cytotoxic effect and the degree of apoptosis in the different cancer cell lines. The present study has also proved cell cycle arrest at G2-M and pre-G1 phases under the effect of IC50 of RCTL and RCT nanocomposites in different cancer lines with the best effect being achieved in HepG2 cells. Ruthenium nanocomposites seem to open a new avenue in cancer therapy.

Synthesis, anticancer activity, and mechanistic investigations of aryl-alkyl diorganotin arylformylhydrazone complexes

Diorganotin acylhydrazone complexes with mitochondrial targeting demonstrate significant potential as replacements for platinum-based complexes due to their potent anticancer properties. Twelve methylphenyltin arylformylhydrazone complexes have been synthesized by microwave “one-pot” reaction. The complexes have been characterized by FT-IR, multinuclear NMR (1H, 13C, and 119Sn), TGA, and HRMS. Crystal structures were determined for 10 out of the 12 complexes under study. Structures 1 through 8, 10 and 12 possessed a central symmetric structure of a di-nuclear Sn2O2 tetrahedral ring. All complexes were tested for their inhibitory activity against human cell lines NCI-H460, MCF-7, and HepG2. Complex 8 exhibited the most effective inhibitory effect on HepG2 cells, with an IC50 value of 1.34 ± 0.04 μM. Preliminary studies on the anticancer mechanism suggest that complex 8 induces apoptosis in HepG2 cells via the mitochondrial pathway, accompanied by G2/M phase cell cycle arrest.

Unveiling the anti-cancer potentiality of phthalimide-based Analogues targeting tubulin polymerization in MCF-7 cancerous Cells: Rational design, chemical Synthesis, and Biological-coupled Computational investigation

The present study deals with an anti-cancer investigation of an array of phthalimide-1,2,3-triazole molecular conjugates with various sulfonamide fragments against human breast MCF-7 and prostate PC3 cancer cell lines. The targeted 1,2,3-triazole derivatives 4a-l and 6a-c were synthesized from focused phthalimide-based alkyne precursors using a facile click synthesis approach and were thoroughly characterized using several spectroscopic techniques (IR, 1H, 13C NMR, and elemental analysis). The hybrid click adducts 4b, 4 h, and 6c displayed cytotoxic potency (IC50 values of 1.49, 1.07, and 0.56 μM, respectively) against MCF-7 cells. On the contrary, none of the synthesized compounds showed apparent cytotoxic efficacy for PC3 cells (IC50 ranging from 9.87- >100 μM). As a part of the mechanism analysis, compound 6c demonstrated a potent inhibitory effect (78.3 % inhibition) of tubulin polymerization in vitro with an IC50 value of 6.53 µM. In addition, biological assays showed that compound 6c could prompt apoptotic cell death and induce G2/M cell cycle arrest in MCF-7 cells. Accordingly, compound 6c can be further developed as an anti-breast cancer agent through apoptosis-induction.

Synthesis, Structure, and Properties of a Copper(II) Binuclear Complex Based on Trifluoromethyl Containing Bis(pyrazolyl)hydrazone.

A new complex of copper(II) with methyl-5-(trifluoromethyl)pyrazol-3-yl-ketazine (H2L) was synthesized with the composition [Cu2L2]∙C2H5OH (1). Recrystallization of the sample from DMSO yielded a single crystal of the composition [Cu2L2((CH3)2SO)] (2). The coordination compounds were studied by single-crystal X-ray diffraction analysis, IR spectroscopy, and static magnetic susceptibility method. The data obtained indicate that the polydentate ligand is coordinated by both acyclic nitrogen and heterocyclic nitrogen atoms. The cytotoxic activity of the ligand and complex 1 was investigated on human cell lines MCF7 (breast adenocarcinoma), Hep2 (laryngeal carcinoma), A549 (lung carcinoma), HepG2 (hepatocellular carcinoma), and MRC5 (non-tumor lung fibroblasts). The complex was shown to have a pronounced dose-dependent cytotoxicity towards these cell lines with LC50 values in the range of 0.18-4.03 μM.

Pharmacological investigation of new niclosamide-based isatin hybrids as antiproliferative, antioxidant, and apoptosis inducers

A group of Niclosamide-linked isatin hybrids (Xo, X1, and X2) was created and examined using IR, 1HNMR, 13C NMR, and mass spectrometry. These hybrids' cytotoxicity, antioxidant, cell cycle analysis, and apoptosis-inducing capabilities were identified. Using the SRB assay, their cytotoxicity against the human HCT-116, MCF-7, and HEPG-2 cancer cell lines, as well as VERO (African Green Monkey Kidney), was evaluated. Compound X1 was the most effective compound. In HCT-116 cells, compound X1 produced cell cycle arrest in the G1 phase, promoted cell death, and induced apoptosis through mitochondrial membrane potential breakdown in comparison to niclosamide and the control. Niclosamide and compound X1 reduced reactive oxygen species generation and modulated the gene expression of BAX, Bcl-2, Bcl-xL, and PAR-4 in comparison to the control. Docking modeling indicated their probable binding modalities with the XIAP BIR2 domain, which selectively binds caspase-3/7, and highlighted their structural drivers of activity for further optimization investigations. Computational in silico modeling of the new hybrids revealed that they presented acceptable physicochemical values as well as drug-like characteristics, which may introduce them as drug-like candidates. The study proved that compound X1 might be a novel candidate for the development of anticancer agents as it presents antiproliferative activity mediated by apoptosis.

Antiproliferative potential of Plinia edulis leaves

Plinia edulis, popularly known as ‘cambucá’, is used in Brazilian folk medicine to treat several conditions. The aim of this study was to evaluate the mutagenicity and cytotoxicity of cambucá leaf extract, as well as its antioxidant activity. The ‘Ames’ test and Orac assay were used to evaluate the mutagenicity and antioxidant activity, respectively, and the phytochemical analysis of the ethanol leaf extract (LE) was performed by chromatographic and spectrometric methods. The in vitro cytotoxicity was tested on CHO (Chinese Hamster Ovary) cells and on nine human tumor cell lines. Phytochemical analysis of LE has revealed the presence of triterpenes and flavonoids. The LE did not show mutagenicity at the concentration of 20 mg plate-1 and exhibited high antioxidant activity, with Orac value of 3948 µmol TE g-1. The LE and its fractions (ethyl acetate; methanol) showed antiproliferative activity against cancer cell lines and proliferative activity in normal cells. The ethyl acetate fraction was the most active extract, presenting antiproliferative activity against strains of breast cancer, prostate cancer, colon cancer, lung cancer, melanoma and leukemia (GI50 0.01-8.57 µg mL-1), being more effective than the reference drug (doxorubicin) against human breast adenocarcinoma MCF-7 cell line. These results suggest P. edulis as a potential adjuvant in cancer therapy and chemoprevention.

Novel tetraaza macrocyclic Schiff base complexes of bivalent zinc: microwave-assisted green synthesis, spectroscopic characterization, density functional theory calculations, molecular docking studies, in vitro antimicrobial and anticancer activities.

In the present manuscript, novel macrocyclic Schiff base complexes [Zn(N4MacL1)Cl2-Zn(N4MacL3)Cl2] were synthesized by the reaction of ZnCl2 and macrocyclic ligands (N4MacL1-N4MacL3) derived from diketone and diamines under microwave irradiation method and conventional method. The structures of the obtained complexes were identified by various spectrometric methods such as Fourier transformation infra-red (FT-IR), nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HR-MS), powder X-ray diffraction, molar conductivity, and UV-vis. The structures of the synthesized compounds were optimized by using the def2-TZV/J and def2-SVP/J Coulomb fitting basis sets at B3LYP level in density functional theory (DFT) calculations. The macrocyclic Schiff base complexes exhibited higher activities against Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus), Gram-negative bacteria (Escherichia coli and Xanthomonas campestris), and fungal strains (Fusarium oxysporum and Candida albicans) in comparison to macrocyclic Schiff base ligands. Furthermore, the newly synthesized macrocyclic compounds were assessed for their anticancer activity against three cell lines: A549 (human alveolar adenocarcinoma epithelial cell line), HT-29 (human colorectal adenocarcinoma cell line), and MCF-7 (human breast adenocarcinoma cell line) using the MTT assay. The obtained results showed that the macrocyclic complex [Zn(N4MacL3)Cl2] displayed the highest cytotoxic activity (2.23 ± 0.25µM, 6.53 ± 0.28µM, and 7.40 ± 0.45µM for A549, HT-29, and MCF-7 cancer cell lines, respectively). Additionally, molecular docking investigations were conducted to elucidate potential molecular interactions between the synthesized macrocyclic compounds and target proteins. The results revealed a consistent agreement between the docking calculations and the experimental data.

Antiproliferative activity of syringic acid-loaded nanostructured lipid carriers against MCF-7 human breast carcinoma cells

Syringic acid (SA) is a phenolic herbal compound known to exert antiproliferative properties. However, its poor aqueous solubility and low bioavailability lead to limited therapeutic efficacy in treating breast cancer. Hence, to overcome the above problems, the current study aims to explore the quality by design (QbD) optimized syringic acid loaded nanostructured lipid carriers (SA-NLCs) to treat breast cancer. Here, SA-NLCs were formulated via the hot-melt emulsification method and optimized using the Box-Behnken design. The SA-NLCs exhibited spherical shapes with a particle size and zeta potential of 142.7 ± 4 nm and −14.5 ± 3.6 mV, respectively. The differential scanning calorimetry and powder XRD analyses showed the conversion of crystalline to amorphous form of SA after entrapping into NLCs. Also, the optimized SA-NLCs showed sustained drug release of 75.5 % and 97.6 % in pH 5.5 acetate buffer solution and pH 7.4 phosphate buffer saline respectively. The drug release kinetics study revealed that the optimized SA-NLCs exhibit the Weibull model with the Fickian drug release mechanism. Further, a significantly improved cytotoxicity of the optimized SA-NLCs (IC50: 3.8 ± 0.2 μg/mL) was observed as compared to free SA (IC50: 14.5 ± 1.2 μg/mL) on MCF-7 human breast carcinoma cell lines. Thus, the improved cytotoxicity of SA-NLCs on MCF-7 cell lines can be a suitable strategy for breast cancer treatment.

MLKL regulates radiation-induced death in breast cancer cells: an interplay between apoptotic and necroptotic signals.

Resistance to caspase-dependent apoptosis is often responsible for treatments failure in cancer. Necroptosis is a type of programmed necrosis that occurs under caspase-deficient conditions that could overcome apoptosis resistance. Our purpose was to investigate the interrelationship between apoptotic and necroptotic death pathways and their influence on the response of breast cancer cells to radiotherapy in vitro. Human BC cell lines MCF-7 and MDA-MB-231 were treated with ionizing radiation, and then several markers of apoptosis, necroptosis, and survival were assessed in the presence and absence of necroptosis inhibition. MLKL knockdown was achieved by siRNA transfection. Our main findings emphasize the role of necroptosis in cellular response to radiation represented in the dose- and time-dependent elevated expression of necroptotic markers RIPK1, RIPK3, and MLKL. Knockdown of necroptotic marker MLKL by siRNA led to a significant elevation in MDA-MB-231 and MCF-7 survival with a dose modifying factor (DMF) of 1.23 and 1.61, respectively. Apoptotic markers Caspase 8 and TRADD showed transitory or delayed upregulation, indicating that apoptosis was not the main mechanism by which cells respond to radiation exposure. Apoptotic markers also showed a significant elevation following MLKL knockdown, suggesting its role either as a secondary or death alternative pathway. The result of our study emphasizes the critical role of the necroptotic pathway in regulating breast cancer cells responses to radiotherapy and suggests a promising utilization of its key modulator, MLKL, as a treatment strategy to improve the response to radiotherapy.

Structural Design, Anticancer Evaluation, and Molecular Docking of Newly Synthesized Ni(II) Complexes with ONS-Donor Dithiocarbazate Ligands.

The current article reports the investigation of three new Ni(II) complexes with ONS-donor dithiocarbazate ligands: [Ni(L1)PPh3] (1), [Ni(L2)PPh3] (2), and [Ni(L2)Py] (3). Single-crystal X-ray analyses revealed mononuclear complexes with a distorted square planar geometry and the metal centers coordinated with a doubly deprotonated dithiocarbazate ligand and coligand pyridine or triphenylphosphine. The non-covalent interactions were investigated by the Hirshfeld surface and the results revealed that the strongest interactions were π⋅⋅⋅π stacking interactions and non-classical hydrogen bonds C-H···H and C-H···N. Physicochemical and spectroscopic methods indicate the same structures in the solid state and solution. The toxicity effects of the free ligands and Ni(II) complexes were tested on the human breast cancer cell line MCF-7 and non-malignant breast epithelial cell line MCF-10A. The half-maximal inhibitory concentration (IC50) values, indicating that the compounds were potent in inhibiting cell growth, were obtained for both cell lines at three distinct time points. While inhibitory effects were evident in both malignant and non-malignant cells, all three complexes demonstrated lower IC50 values for malignant breast cell lines than their non-malignant counterparts, suggesting a stronger impact on cancerous cell lines. Furthermore, molecular docking studies were performed showing the complex (2) as a promising candidate for further therapeutic exploration.

New bioactive titanium(IV) derivatives with their DFT, molecular docking, DNA/BSA interaction, antioxidant and in-vitro investigations

A set of four new metallacyclic complexes titanium(IV) associated with Schiff bases (SBs) (1a- 1d) obtained by the specific reactions of β-diketones such as acetylacetone (acacH) and benzyl acetone (bzacH) and aminophenol derivatives while treating Ti(OPri)4 and these SBs individually in 1:2 stoichiometry under 8 h reflux condition in anhydrous benzene to afford as reddish powder (2a-2d). These products have been purified in repeated washings of dry n-hexane afterwards, subjected to characterization by suitable spectroscopic techniques (NMR, IR, UV–Vis and HRMS). These hexacoordinated complexes appeared as distorted octahedral geometry from computational data studies. The synthesized titanium(IV) complexes were screened for their antioxidant abilities where 2c and 2d exhibited remarkable activity as IC50 values. The DNA & BSA binding properties of the complexes (2a-2d) have also been investigated through electronic absorption and molecular docking analysis. The obtained results indicated clearly that the complexes got bound with DNA via groove binding mode according to the intrinsic binding constant values (Kb = 1.5 × 104 M−1 to 7.5 × 105 M−1). Derivative 2c was examined in-vitro on a panel of cancerous cell line − breast cancer and human colon cell lines MCF-7 to reflect IC50 results as 53.92 μg/mL and HT-29 33.43 μg/mL, respectively.

Design, synthesis and mechanistic studies of novel arylformylhydrazone butylphenyltin complexes as potential anticancer agents

Many diorganotin complexes with various alkyl groups exhibit excellent in vitro anticancer activity. However, most diorganotin is the same alkyl group, and the asymmetric alkyl R group has been rarely reported. Hence, in this paper, twenty butylphenyl mixed dialkyltin arylformylhydrazone complexes have been synthesized by microwave “one-pot” reaction with arylformylhydrazine, substituted α-keto acid or its sodium salt and butylphenyltin dichloride. The crystal structures of nine complexes were determined, indicating that the complexes C1, C2, C11, C12, and C16 ∼ C19 possessed a central symmetric structure of a dinuclear Sn2O2 tetrahedral ring; while the complex C9 is a trinuclear tin-oxygen cluster with a 6-membered ring encased in a 12-membered macrocyclic structure. The inhibiting activity of complexes was tested against the human cell lines NCI-H460, MCF-7, HepG2, Huh-7 and HL-7702. Complex C2 demonstrated the optimal inhibitory effect on HepG2 cells, with an IC50 value of 0.82 ± 0.03 μM. Cellular biology experiments revealed that complex C2 could induce apoptosis and G2/M phase cell cycle arrest in HepG2 and Huh-7 cells. The complex also caused the collapse of the mitochondrial membrane potential and increased intracellular reactive oxygen species in HepG2 and Huh-7 cells. Western blot analysis further clarified that complex C2 could induce cell apoptosis through the mitochondrial pathway along with the release of reactive oxygen species.

Synthesis, crystal structure, Hirshfeld, DFT, molecular docking, dynamics studies, and anti-cancer activity of 1-substituted-2-(4-(diethylamino)-2-hydroxyphenyl)- 1H-benzo[d]imidazole-5-ethyl carboxylates

In our present work, a novel series of 1-substituted-2–2-(4-(diethylamino)-2-hydroxyphenyl)- 1H-benzo[d]imidazole-5-ethyl carboxylates were synthesized by an efficient “one-pot” nitro reductive cyclization method using sodium dithionite is reported as potential anticancer agents. IR, 1H & 13C NMR and Mass spectral data confirmed the synthesized compounds' structure. Compound 6a and 6j were confirmed by their single crystal XRD studies. The Hirshfeld surfaces computational method was applied to visualize and analyse the intermolecular interactions within the crystal structure. All the synthesized compounds were assessed for in vitro anticancer activity towards human lung adenocarcinoma A549 cells and breast cancer MCF-7 cell lines. Compound 6j showed a promising activity with an IC50 value 42.7 μg/mL and 89.63 μg/mL against A549 and MCF-7 cell lines respectively. The potent compounds were assessed for cytotoxicity study on human embryonic kidney HEK 293 cell line and found to be non-toxic. Also, apoptosis study indicated compound 6j induced early apoptosis in the A549 lung adenocarcinoma and MCF-7 breast cancer cells. Molecular docking and dynamic simulation studies were carried out on human estrogen receptor protein (PDB: 3ERT).

Isolation and structure determination of a new bisabolane-type sesquiterpenoid with cytotoxicity from Penicillium oxalicum MZY-202312-521

Endophytic fungi can produce attractive secondary metabolites with various biological activities that have contributed significantly to pharmacotherapy. In this study, three bisabolane-type sesquiterpenoids, including a new one, namely, inonotic acid C (1), together with previously reported compounds (S)-(+)-11-dehydrosydonic acid (2) and sydonic acid (3), were isolated from a marine algal-derived endophytic fungus Penicillium oxalicum MZY-202312-521. Their structures were determined by means of extensive spectroscopic analyses. The absolute configurations of inonotic acid C (1) were established by single-crystal X-ray diffraction method. In vitro cytotoxic experiments on human A549, MCF-7, HeLa, and HepG2 carcinoma cell lines were carried out. The new compound inonotic acid C (1) was found to possess strong inhibitory activity against the MCF-7 cell line, with an IC50 value of 7.7 μM.

The Synthesis and Analysis of the Cytotoxicity of Al2O3-Supported Silver Nanoparticles Prepared by the Plasma Chemical Process Initiated by Pulsed MW Radiation in the Al2O3-Ag Powder Mixtures.

An original plasma chemical process initiated by microwave discharge in a mixture of metal and dielectric powders was applied to prepare specific materials, which consisted of microsized spherical particles of aluminum oxide covered with silver nanoparticles. The prepared materials are highly uniform in shape, size distribution, and composition. Their cytotoxicity was investigated using the human cell lines MCF7, HEK293T, A549, and VA-13 and the bacterial strains E. coli JW5503 (ΔtolC) and E. coli K12. Their cytotoxicity was found not to exceed the cytotoxicity of the starting materials. Thus, the prepared materials can be considered highly promising for catalysis and biotechnology applications.

Cytotoxic potential and metabolomic profiling of alkaloid rich fraction of Tylophora indica leaves

Tylophora indica (Burm f.) Merrill, belong to family Asclepiadaceae, is considered to be a natural remedy with high medicinal benefits. The objective of this work is to assess the metabolomic profile of T. indica leaves enriched in alkaloids, as well as to evaluate the in vitro cytotoxicity of these leaves using the MTT assay on human breast MCF-7 and liver HepG2 cancer cell lines. Dried leaves of T. indica were extracted by sonication, using methanol containing 2 % (v/v) of acetic acid and obtained fraction was characterized by HPTLC and UPLC-MS. The UPLC-MS study yielded a preliminary identification of 32 metabolites, with tylophorine, tylophorine B, tylophorinine, and tylophorinidine being the predominant metabolites. The cytotoxicity of the extract of T. indica was evaluated on HepG2 and MCF-7 cell lines, yielding inhibitory concentration (IC50) values of 75.71 μg/mL and 69.60 μg/mL, respectively. Data suggested that the phytochemical screening clearly showed presence of numerous secondary metabolites with moderate cytotoxic efficacy. In conclusion, the future prospects of T. indica appear promising for the advancement of phytopharmaceutical-based anticancer medications, as well as for the design of contemporary pharmaceuticals in the field of cancer chemotherapy.

Synthesis, characterisation and in vitro anticancer activity of conjugated protease inhibitor-silver nanoparticles (AgNPs-PI) against human breast MCF-7 and prostate PC-3 cancer cell lines.

The conjugated silver nanoparticles using biomolecules have attracted great attention of researchers because physical dimensions and surface chemistry play important roles in toxicity and biocompatibility of AgNPs. Hence, in the current study, synthesis of bio-conjugated AgNPs with protein protease inhibitor (PI) isolated from Streptomyces spp. is reported. UV-visible spectra of PI and AgNPs showed stronger peaks at 280 and 405nm, confirming the synthesis of conjugated AgNPs-PI. TEM and SEM images of AgNPs-PI showed spherical-shaped nanoparticles with a slight increase in particle size and thin amorphous layer around the surface of silver nanomaterial. Circular dichroism, FT-IR and fluorescence spectral studies confirmed AgNPs-PI conjugation. Conjugated AgNPs-PI showed excellent anticancer potential than AgNPs and protease inhibitor separately on human breast MCF-7 and prostate PC-3 cell lines. The findings revealed that surface modification of AgNPs with protein protease inhibitor stabilised the nanomaterial and increased its anticancer activity.

Engineered Biosynthesis and Anticancer Studies of Ring-Expanded Antimycin-Type Depsipeptides.

Respirantins are 18-membered antimycin-type depsipeptides produced by Streptomyces sp. and Kitasatospora sp. These compounds have shown extraordinary anticancer activities against a panel of cancer cell lines with nanomolar levels of IC50 values. However, further investigation has been impeded by the low titers of the natural producers and the challenging chemical synthesis due to their structural complexity. The biosynthetic gene cluster (BGC) of respirantin was previously proposed based on a bioinformatic comparison of the four members of antimycin-type depsipeptides. In this study, we report the first successful reconstitution of respirantin in Streptomyces albus using a synthetic BGC. This heterologous system serves as an accessible platform for the production and diversification of respirantins. Through polyketide synthase pathway engineering, biocatalysis, and chemical derivatization, we generated nine respirantin compounds, including six new derivatives. Cytotoxicity screening against human MCF-7 and Hela cancer cell lines revealed a unique biphasic dose-response profile of respirantin. Furthermore, a structure-activity relationship study has elucidated the essential functional groups that contribute to its remarkable cytotoxicity. This work paves the way for respirantin-based anticancer drug discovery and development.

Cytotoxic indole diterpenoids and rare pyridoxatin atropisomers from the endophytic fungus Tolypocladium sp. SHJJ1

Phytochemical investigation on the extract of endophytic fungus Tolypocladium sp. SHJJ1 resulted in the identification of a pair of previously undescribed pyridoxatin atropisomers [1 (M/P)] and three new indole diterpenoids (3–5), together with a pair of known pyridoxatin atropisomers [2 (M/P)] and ten known indole diterpenoids (6–15). Their structures, including their absolute configurations were elucidated by extensive spectroscopic analysis, quantum chemical calculations, and X-ray diffraction. Among the undescribed natural products, [1 (M/P)] that two rapidly interconverting atropisomers are the third example to report in the pyridoxatin atropisomers. Except for compounds 1 (M/P) and 2 (M/P), all other compounds were tested for their cytotoxicity using HepG2, A549, and MCF-7 human cell lines. Compound 9 displayed moderate cytotoxicity against the HepG2, A549, and MCF-7 cell lines with IC50 values of 32.39 ± 1.48 μM, 26.06 ± 1.14 μM, and 31.44 ± 1.94 μM, respectively, which was similar to the positive drug cisplatin (with IC50 values of 32.55 ± 1.76 μM, 18.40 ± 1.43 μM, and 27.31 ± 1.22 μM, respectively).

A pyridyl-benzimidazole based ruthenium(II) complex as optical sensor: Targeted cyanide detection and live cell imaging applications

An extreme toxicity of cyanide (CN−) ion in diverse environmental media has encouraged significant attention for scheming well-organised molecular probes for its selective and sensitive detection. Keeping in mind, we present here a monometallic Ru(II) complex (Ru-1) based on 2-(pyridin-2-yl)-1H-benzo[d]imidazole moiety acting as a highly selective luminescent probe for CN− recognition in pure water. Besides, Ru-1 also acted as an efficient sensor for F−, AcO− and H2PO4− ions along with CN− when acetonitrile was chosen as solvent system. The binding constant (Kb) and detection limit (LoD) for CN− have been depicted as 3.05 × 106 M−1 and 12.8 nM, respectively, in water. The close proximity of N-H site with Ru(II) centre along with its remarkable acidity were identified as mainly responsible for the high selectivity of Ru-1 toward CN− in water. Job’s plot and DFT analyses were carried out to support the anion binding mechanism. Furthermore, the time-resolved fluorescence (TRF) spectroscopy was performed to assess the cyanide-induced emission lifetime change of Ru-1 in aqueous medium. In order to investigate applied potential, the probe Ru-1 was notably developed into paper-based strips that could readily detect CN− ion in mM range via naked eye under 365 nm light illumination, and also adequately employed to detect CN− in human breast cancer MCF-7 cell lines and natural food sources (such as apple seeds and sprouting potatoes).