Exploration of the cytotoxic and microtubule disruption potential of novel imidazo[1,5-]pyridine-based chalcones.

In continuation of our efforts to develop new anticancer compounds, a new series of imidazo[1,5-]pyridine-chalcone derivatives was designed, synthesized, characterized, and evaluated for its cytotoxicity against five human cancer cell lines, , breast (MDA-MB-231), colon (RKO), bone (Mg-63), prostate (PC-3), and liver (HepG2) cell lines, as well as a normal cell line (HEK). Among the synthesized compounds, two exhibited promising cytotoxicity against the MDA-MB-231 cell line with IC values of 4.23 ± 0.

Photodynamic Inactivation of Bacteria Using Nickel(II) Complexes with Catecholate and Phenanthroline Ligands.

Metal complexes activated by light can combat infections by triggering the photodynamic inactivation of bacteria. Herein, we report six mixed-ligand nickel(II) complexes with the formulation [Ni(NN)(L)] (1-6), where NN represents an N,N-donor phenanthroline ligand, specifically 1,10-phenanthroline (phen in 1, 2), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq in 3, 4), and dipyrido[3,2-a:2',3'-c]phenazine (dppz in 5, 6), while L is an O,O donor bidentate ligand derived from catechol (cat, in 1, 3, 5) or esculetin (esc, in 2, 4, 6). The paramagnetic d octahedral complexes demonstrated good dark and photostability in the solution phase and exhibited significant light absorption in the visible (400-700 nm) region.

A dipyridophenazine Ni(II) dithiolene complex as a dual-acting cancer phototherapy agent activatable within the phototherapeutic window.

A combination of photodynamic therapy (PDT) and photothermal therapy (PTT) within the phototherapeutic window (600-900 nm) can lead to significantly enhanced therapeutic outcomes, surpassing the efficacy observed with PDT or PTT alone in cancer phototherapy. Herein, we report a novel small-molecule mixed-ligand Ni(II)-dithiolene complex (Ni-TDD) with a dipyridophenazine ligand, demonstrating potent red-light PDT and significant near-infrared (NIR) light mild-temperature PTT activity against cancer cells and 3D multicellular tumour spheroids (MCTSs). The four-coordinate square planar complex exhibited a moderately intense absorption band (ε ∼ 3700 Mcm) centered around 900 nm and demonstrated excellent dark and photostability in an aqueous phase.

Exploration of mercaptoacetamide-linked pyrimidine-1,3,4-oxadiazole derivatives as DNA intercalative topo II inhibitors: Cytotoxicity and apoptosis induction.

The design and synthesis of a new series of mercaptoacetamide-linked pyrimidine-1,3,4-oxadiazole hybrids was accomplished. The in vitro cytotoxic potential of these new compounds was evaluated against lung cancer (A549), prostate cancer (PC-3, DU-145) and human embryonic kidney (HEK) cell lines. Compound 9p showed the highest potency on A549 cells with an IC value of 3.

Co-encapsulated nanoparticles of Erlotinib and Quercetin for targeting lung cancer through nuclear EGFR and PI3K/AKT inhibition.

Erlotinib-based EGFR targeted therapy has proven significant clinical improvement against non-small cell lung cancer (NSCLC). However, the anticancer activity of Erlotinib (Ertb) is limited by the development of Ertb resistance and possess a challenge to clinicians and patients. To explore a better therapeutic strategy, we evaluated Ertb in combinations with different natural products.

Synthesis and biological evaluation of novel imidazo[1,2-a]pyridine-oxadiazole hybrids as anti-proliferative agents: Study of microtubule polymerization inhibition and DNA binding.

Efforts towards the development of potential anticancer agents, a new series of imidazo[1,2-a]pyridine-oxadiazole hybrids were synthesized and evaluated for their in vitro anticancer activity against lung cancer (A549) and prostate cancer (PC-3, DU-145) cell lines. Amongst the compounds tested, 6d showed the highest potency on A549 cells with an IC value of 2.8 ± 0.

Design and synthesis of substituted (1-(benzyl)-1-1,2,3-triazol-4-yl)(piperazin-1-yl)methanone conjugates: study on their apoptosis inducing ability and tubulin polymerization inhibition.

A library of substituted (1-(benzyl)-1-1,2,3-triazol-4-yl)(piperazin-1-yl)methanone derivatives were designed, synthesized and screened for their cytotoxic activity against BT-474, HeLa, MCF-7, NCI-H460 and HaCaT cells by employing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Among all the synthesized analogues, compound displayed the highest cytotoxicity with the IC value of 0.99 ± 0.

A facile and metal-free domino reaction of TsDAM and 2-alkenylarylaldehyde: An easy access to 8-hydroxy-2,8-dihydro indeno [2,1-]pyrazoles.

An efficient straightforward metal free domino approach was developed for the synthesis of various 8-hydroxy-2,8-dihydroindeno[2,1-c]pyrazoles via [3 + 2] cycloaddition of substituted alkenes and TsDAM (TosylDiAzoMethane). The salient features of this protocol include high efficiency, mild reaction conditions, greener solvent, metal-free reaction, scalability and broad substrate scope along with high regioselectivity and yields.

New imidazo[2,1-]thiazole-based aryl hydrazones: unravelling their synthesis and antiproliferative and apoptosis-inducing potential.

Herein, we have designed and synthesized new imidazo[2,1-]thiazole-based aryl hydrazones () and evaluated their anti-proliferative potential against a panel of human cancer cell lines. Among the synthesized compounds, and elicited promising cytotoxicity against the breast cancer cell line MDA-MB-231 with IC values of 1.65 and 1.

Design and synthesis of β-carboline linked aryl sulfonyl piperazine derivatives: DNA topoisomerase II inhibition with DNA binding and apoptosis inducing ability.

A series of new β-carboline linked aryl sulfonyl piperazine congeners have been synthesized by coupling various β-carboline acids with substituted aryl sulfonyl piperazines. Evaluation of their anticancer activity against a panel of human cancer cell lines such as colon (HT-29), breast (MDA-MB-231), bone osteosarcoma (MG-63), brain (U87 MG), prostate (PC- 3) and normal monkey kidney (Vero) cell line has been done. Among the series, compound 8ec and 8ed has shown most potent cytotoxicity with an IC values of 2.

Novel diindoloazepinone derivatives as DNA minor groove binding agents with selective topoisomerase I inhibition: Design, synthesis, biological evaluation and docking studies.

We present here-in the molecular design and chemical synthesis of a novel series of diindoloazepinone derivatives as DNA minor groove binding agents with selective topoisomerase I inhibition. The in vitro cytotoxicity of the synthesized compounds was evaluated against four human cancer cell lines including DU143, HEPG2, RKO and A549 in addition to non-cancerous immortalized human embryonic kidney cells (HEK-293). Compound 11 showed significant cytotoxicity against all the four human cancer cell lines with IC values ranging from 4.

Regioselective Ring Expansion of 3-Ylideneoxindoles with Tosyldiazomethane (TsDAM): A Metal-Free and Greener Approach for the Synthesis of Pyrazolo-[1,5-]quinazolines.

An efficient, metal-free approach to access pyrazolo-[1,5-]quinazolines with 3-ylideneoxindoles and tosyldiazomethane (TsDAM) under mild aqueous reaction conditions has been developed and the solvent involvement in the present reaction has also been explored for the first time. This greener approach involves 1,3-dipolar cycloaddition, regioselective ring expansion, followed by the elimination of tosyl group with aqueous base in a single operation, and the product can be isolated in high purity without column chromatographic separation. The method is also compatible with a large variety of functional groups, providing good to excellent yields in water, thus resulting in a decrease of environmental impact in the pharmaceutical industry.

Regioselective ring expansion followed by H-shift of 3-ylidene oxindoles: a convenient synthesis of N-substituted/un-substituted pyrrolo[2,3-] quinolines and marinoquinolines.

Herein, we report a simple and metal-free protocol for the synthesis of 4-oxo-4,5-dihydro-3-pyrrolo[2,3-]quinolines. The present method under mild reaction conditions with wide functional group compatibility gives several unexplored N-substituted/unsubstituted 4-oxo-4,5-dihydro-3-pyrrolo[2,3-]quinolines and marinoquinolines in good to excellent yields. Mechanistic insights for the synthesis of N-substituted pyrroloquinolines reveal the ring expansion of 3-ylideneoxindoles and H-shift as the key steps.

Solvent-Controlled, Tunable Domino Reaction of 3-Ylideneoxindoles with in Situ-Generated α-Aryldiazomethanes: A Facile Access to 3-Spirocyclopropyl-2-oxindole and Pyrazoloquinazolinone Scaffolds.

A mild and efficient solvent-controlled, metal-free switchable 1,3-dipolar cycloaddition/ring contraction or ring expansion domino reaction of 3-ylideneoxindoles with in situ-generated α-aryldiazomethanes has been developed. This domino reaction provided a series of aryl-substituted 3-spirocyclopropyl-2-oxindoles and pyrazoloquinazolinones with excellent regio- and diastereoselectivity from common substrates under varying solvent conditions.

Discovery of certain benzyl/phenethyl thiazolidinone-indole hybrids as potential anti-proliferative agents: Synthesis, molecular modeling and tubulin polymerization inhibition study.

A series of certain benzyl/phenethyl thiazolidinone-indole hybrids were synthesized for the study of anti-proliferative activity against A549, NCI-H460 (lung cancer), MDA-MB-231 (breast cancer), HCT-29 and HCT-15 (colon cancer) cell lines by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). We found that compound G37 displayed highest cytotoxicity with IC value of 0.92 ± 0.

Synthesis of new triazole fused imidazo[2,1-b]thiazole hybrids with emphasis on Staphylococcus aureus virulence factors.

A series of new triazole fused imidazo[2,1-b]thiazole hybrids (9a-u) were designed, synthesized and evaluated as antimicrobial agents. Compounds 9c, 9d, 9e, 9j and 9l showed promising broad spectrum antimicrobial activity. Further, compound 9c exhibited significant anti-biofilm activity with single and mixed biofilm disruption demonstrated by Field Emission Scanning Electron Microscope (FE-SEM).

A Comprehensive Review on the Therapeutic Versatility of Imidazo [2,1-b]thiazoles.

Background: Imidazo[2,1-b]thiazole, a well-known fused five-membered hetrocycle is one of the most promising and versatile moieties in the area of medicinal chemistry. Derivatives of imidazo[2,1-b]thiazole have been investigated for the development of new derivatives that exhibit diverse pharmacological activities. This fused heterocycle is also a part of a number of therapeutic agents.

Design, synthesis, and antimicrobial evaluation of 1,4-dihydroindeno[1,2-]pyrazole tethered carbohydrazide hybrids: exploring their ADMET, ergosterol inhibition and ROS inducing potential.

A series of new 1,4-dihydroindeno[1,2-]pyrazole tethered carbohydrazide hybrids () were designed, synthesized and evaluated for their antimicrobial activity. Compounds , , , and demonstrated significant activity against the entire panel of test pathogens. Further, compounds and exhibited significant anti- activity.

Synthesis and biological evaluation of new bisindole-imidazopyridine hybrids as apoptosis inducers.

A series of diindolylmethanes (5a-t) were designed, synthesized, and examined for their cytotoxicity against four human cancer cell lines like prostate (DU-145), lung (A549), breast (MCF-7) and cervical cancer (HeLa). These results revealed that among all the hybrids, two (5k and 5r) were identified and exhibited significant cytotoxic effect against A549 cancer cells with IC values of 1.65 ± 0.

Nimbolide protects against endotoxin-induced acute respiratory distress syndrome by inhibiting TNF-α mediated NF-κB and HDAC-3 nuclear translocation.

Acute respiratory distress syndrome (ARDS) is characterized by an excessive acute inflammatory response in lung parenchyma, which ultimately leads to refractory hypoxemia. One of the earliest abnormalities seen in lung injury is the elevated levels of inflammatory cytokines, among them, the soluble tumor necrosis factor (TNF-α) has a key role, which exerts cytotoxicity in epithelial and endothelial cells thus exacerbates edema. The bacterial lipopolysaccharide (LPS) was used both in vitro (RAW 264.

LC/QTOF/MS/MS characterization, molecular docking and in silico toxicity prediction studies on degradation products of anagliptin.

Pharmaceutical drugs are potential molecules with specific biological activity. However, long-term use of these chemical molecules can affect the human physiological system because of their increased levels in the human body. Therefore, identification and structure elucidation of impurities or degradation products should be taken into consideration in order to assure drug safety.

Regioselective Ring Expansion of Isatins with In Situ Generated α-Aryldiazomethanes: Direct Access to Viridicatin Alkaloids.

A novel efficient one-pot regioselective ring-expansion reaction of isatins with in situ generated α-aryl/heteroaryldiazomethanes for the construction of viridicatin alkaloids has been described under metal-free conditions. The utility of this protocol is further demonstrated in the synthesis of naturally occurring viridicatin, viridicatol, and substituted 3- O-methyl viridicatin and their scale up.

Synthesis, molecular modeling and evaluation of α-glucosidase inhibition activity of 3,4-dihydroxy piperidines.

Biological evaluation of 3,4-dihydroxy piperidines as α-glucosidase inhibitors is being reported for the first time. Forty-five derivatives (amides, di-amides and sulfonamides) were made using cis and trans 3,4-dihydroxy piperidines to evaluate their α-glucosidase inhibition activity. Polar groups (-OH, -NH) on phenyl ring having derivatives 5i, 5l, 7g, 7i &12j showed excellent activity compared to standard references.

Curcumin inspired 2-chloro/phenoxy quinoline analogues: Synthesis and biological evaluation as potential anticancer agents.

Synthesis of twenty new curcumin inspired 2-chloro/phenoxy quinoline derivatives is outlined in this study. The obtained new chemical entities were screened in vitro for their cytotoxic activity towards various tumor cell lines. Of the compounds screened, 6c and 9d exhibited significant activity and the most active analogue 6c displayed promising cytotoxicity against PC-3 (IC of 3.

Synthesis and biological evaluation of longanlactone analogues as neurotrophic agents.

Longanlactone analogues were synthesized using a route featuring Friedel-Crafts acylation, Sonogashira coupling and 1,3-dipolar cycloaddition reactions. Structure-activity relationships were investigated for neurotrophic activity. Compound 6 was found to have the most potent neurotrophic activity among all the synthesized analogues in Neuro2a cells as evidenced by a battery of in vitro/cell based assays for assessment of neurogenic and potential neurotrophic activity including neurite outgrowth assay and real time PCR for popular markers of augmented neurotrophic activity.