Environmentally benign synthesis, molecular properties prediction and anti-inflammatory activity of novel isoxazolo[5,4-d]isoxazol-3-yl-aryl-methanones via vinylogous Henry nitroaldol adducts as synthons

Novel thiazolones for the simultaneous modulation of PPARγ, COX-2 and 15-LOX to address metabolic disease-associated portal inflammation

A hybrid pharmacophore model, based on structural motifs previously identified by our team, was employed to generate ligands that simultaneously target COX-2, 15-LOX, and PPARγ in the context of metabolic dysfunction-associated fatty liver disease (MAFLD). Notable COX-2 inhibitory activities (IC50 = 0.065-0.24 μM) were observed relative to celecoxib (IC50 = 0.049 μM). The two most effective 15-LOX inhibitors, 2a and 2b, exhibited 69 % and 57 % of quercetin's action, respectively. Utilizing the rat hemi-diaphragm model to assess in vitro glucose uptake capacity, compounds 2a and 2b demonstrated significant glucose uptake potential in the absence of insulin, surpassing that of pioglitazone. Compound 2a activated PPARγ with an EC50 value of 3.4 μM in a Gal4-hybrid reporter gene assay, indicating partial agonistic action. Interesting binding interactions with targets of interest were identified by molecular docking studies. As well, the expression levels of 20-HETE, Il-1β and TNF-α were decreased in LPS-challenged RAW264.7 macrophages upon treatment with compound 2a. The pharmacokinetic analysis of 2a and assessment of its in vivo efficacy in addressing hepatic impairment in rat models of diabetes and pre-diabetes were carried out. Together, these findings may offer preliminary insights into the potential of these compounds for further refinement in the existing therapeutic arsenals for metabolic diseases.

In Vitro and In Silico Cytotoxic Activity of Isocordoin from Adesmia balsamica Against Cancer Cells

This study investigates the anticancer potential of isocordoin, a prenylated chalcone found in Adesmia balsamica. In vitro assays on colorectal (HT-29), breast (MCF-7) and prostate (PC-3) cancer cell lines, together with a non-cancerous colon cell line (CoN CCD841), revealed that isocordoin is cytotoxic, with PC-3 and MCF-7 cells showing the highest sensitivity. The selectivity index was higher for PC-3 (5.2) than for MCF-7 (3.7) and HT-29 (2.9). Isocordoin induced morphological changes suggestive of apoptosis in tumor cells. Mechanistic studies on HT-29 and MCF-7 lines indicated that isocordoin might possess antioxidant properties while promoting the loss of mitochondrial membrane potential and caspases activation. Molecular docking showed a favorable interaction of isocordoin with caspase-3, which could explain its apoptotic effects. In silico predictions suggest that isocordoin has drug-like properties, including good absorption and permeability to the blood-brain barrier. The presence of the prenyl chain in isocordoin appears crucial for cytotoxic activity, supported by its higher lipophilicity and better interaction with caspase-3 compared to non-prenylated 2',4'-dihydroxychalcone. Overall, isocordoin demonstrates promising anticancer activity, warranting further investigation as a potential therapeutic agent.

Design and application of intramolecular arylogous nitroaldol condensation to access 2-aryl-benzofuran and -indole derivatives and formal synthesis of saprisartan

This study presents the design and application of intramolecular arylogous nitroaldol (Henry) condensation. A transition metal-free, base-mediated reaction of ortho-heteroatom-substituted aryl aldehydes/ketones and 2-nitrobenzyl (pseudo)halides has been developed to access a wide range of 2-(2-nitroaryl)benzofuran/2-(2-nitroaryl)indole derivatives in high yields. The reaction appears to proceed through O-/N-benzylation and intramolecular arylogous nitroaldol condensation. The application potential of the presented strategy has been demonstrated in the formal synthesis of anti-hypertensive agent saprisartan through the efficient synthesis of an advanced key intermediate, which has been accomplished in a ten-fold high overall yield by using resourceful, inexpensive and less-toxic reagents compared to the known methods.

New N-amino-5-cyano-6-pyridones as antimicrobial small molecules endowed with DNA gyrase a inhibitory activity: design, one-pot synthesis, biological assessment and in silico insights

A set of innovative N-amino-5-cyano-6-pyridones derivatives was developed and produced using one-pot three-component procedures. The evaluated molecules were examined for their antimicrobial efficacy. Based on the acquired findings, most of the investigated compounds had promising antimicrobial properties. Out of these derivatives of 3-cyanopyridine, compounds 3d and 3e exhibited minimum inhibitory concentrations (MIC) of 3.91 µg/mL against E.coli. In vitro evaluation of DNA gyrase A displayed that molecule 3d exhibited promising potency as an inhibitor, with an IC50 value of 1.68 µg/mL compared to ciprofloxacin (IC50 = 0.45 µg/mL). Furthermore, it was observed that molecule 3e exhibited a moderate inhibitory effect, as indicated by its IC50 value of 3.77 µg/mL. A kinetics study conducted to assess the time required to kill E. coli bacteria demonstrated that gentamycin and compounds 3d and 3e exhibited bactericidal effects within a time frame of 90-120 min. Based on the ADME predictions, compounds 3d and 3e are expected to have favorable oral bioavailability and are unlikely to penetrate the blood-brain barrier. Computational mutagenicity and tumorigenicity studies were conducted on compounds 3d and 3e. The molecular docking investigation has conclusively demonstrated the binding of compounds 3d and 3e to the target DNA gyrase A enzyme, further reinforcing the existing data.

Synthesis of 4-sulfamoyl phenyl diazocarboxylic acid derivatives as novel non-classical inhibitors of human carbonic anhydrase II activity: an in vitro study

The first class of carbonic anhydrase inhibitors (CAIs) discovered was sulfonamides, but their clinical use is limited due to side effects caused by their inhibition of multiple CA isoforms. To overcome this, researchers have focused on developing isoform-selective CAIs. This study involved the synthesis and characterization of novel carboxylic acid/sulfonamide derivatives. We investigated the interaction between these compounds and the human carbonic anhydrase II (hCA II) isoform using spectroscopic and computational methods. The synthesized compounds were evaluated based on their IC50, Kd and Ki values, and it was found that the inhibitory potency and binding affinity of the compounds increased with the number of carboxylic acids zinc binding groups. Specifically, the compound C4, with three carboxylic acid groups, showed the strongest inhibitory potency. Fluorescence measurements revealed that all compounds quenched the intrinsic fluorescence of hCA II through a dynamic quenching process, and each compound had one binding site in the hCA II structure. Thermodynamic analysis indicated hydrogen bonds and van der Waals interactions played key roles in the binding of these compounds to hCA II. Docking studies showed that the carboxylic acid groups directly attached to the zinc ion in the active site, displacing water/hydroxide ions and causing steric hindrance. Overall, the strengthening of inhibitory activity and the binding power of these carboxylic acid derivatives for the hCA II makes these compounds interesting for designing novel hCA II inhibitors.

Synthesis, in-vitro inhibition of cyclooxygenases and in silico studies of new isoxazole derivatives

Isoxazole belongs to the class of five-membered heterocyclic compounds. The process of developing new drugs has significantly gained attention due to inadequate pharmacokinetic and safety attributes of the available drugs. This study aimed to design a new diverse array of ten novel isoxazole derivatives via Claisen Schmidt condensation reaction. In vitro COX-1/2 anti-inflammatory assay, in silico molecular docking of potent compounds, Molecular docking simulation, and SwissADME pharmacokinetic profile were investigated in this research. The in vitro COX-1 and COX-2 enzyme inhibitory assay showed that almost all the tested compounds exhibited anti-inflammatory effects whereas C6, C5, and C3 were found to be the most potent COX-2 enzyme inhibitors among the tested compounds and are good candidates for selective COX-2 inhibitors. In silico molecular docking studies coupled with molecular dynamic simulation has been done to rationalize the time-evolved mode of interaction of selected inhibitor inside the active pockets of target COX-2. The binding orientations and binding energy results also showed the selectivity of compounds towards COX-2. Physicochemical properties, pharmacokinetic profile, lipophilicity, water solubility, drug metabolism, drug-likeness properties, and medicinal chemistry of the synthesized isoxazole derivatives were assessed. The SwissADME (absorption, distribution, metabolism, and excretion) database was used to assess the physicochemical properties and drug-likeness properties of the synthesized isoxazole derivatives. All the compounds were shown high GI absorption except Compound 7 (C7). Compound 1 (C1) and Compound 2 (C2) were found to cross the blood-brain barrier (BBB). Lipinski's rule of five is not violated by any of the ten synthesized isoxazole derivatives. It was predicted with the SwissADME database that C2, C5, C6, C7, and C8 are potent inhibitors of cytochrome (CYP) subtype CYP-2C19. A subtype of CYP-2C9 was inhibited by C4 and C7. The medicinal chemistry of all the compounds C1-C10 showed no PAIN (Pan assay interference compounds) alerts. The improved gastrointestinal (GI) absorption and BBB permeability of C1 and C2 can provide a future prospective for new researchers in the medicinal field to investigate the compounds for the management of chronic diseases. The synthesized isoxazole compounds showed excellent in vitro COX-1/2 enzymes anti-inflammatory investigations, in silico studies, good physicochemical properties, and improved pharmacokinetic profile which will be further investigated via in vivo anti-inflammatory activities. Moreover, to further support our findings of the computational research and in vitro studies, an in-vivo pharmacokinetic profile is suggested in the future.

Synthesis, reactions and application of chalcones: a systematic review

Chalcones are a group of naturally occurring compounds that have biological effects that include anti-inflammatory, anti-cancer, and antibacterial properties. Current chalcone research, including their synthesis, structure-activity relationships, and biological activities, is summarized herein. Along with their toxicity and safety profiles, the prospective usage of chalcones in medicinal research and development is discussed. This review emphasizes the need for additional research in order to fully examine the therapeutic potential of chalcones as therapeutic agents for the treatment of a variety of disorders.

Chiral spirocyclic phosphoric acid-catalyzed enantioselective synthesis of heterotriarylmethanes bearing an amino acid moiety

We present herein an enantioselective protocol for the chiral phosphoric acid-catalyzed addition of 3-arylisoxazol-5-amines to highly reactive 3-methide-3H-pyrroles to provide a diverse range of heterotriarylmethanes bearing an amino acid moiety in good yields (up to 97%) and high enantioselectivities (up to 93% ee) under mild conditions. The chiral spirocyclic phosphoric acid is crucial in converting the initial 1H-pyrrol-3-yl carbinols into reactive 3-methide-3H-pyrroles and obtaining the good enantiocontrol, thereby facilitating the desired enantioselective transformation.

Molecular Docking and Dynamic Simulation Revealed the Potential Inhibitory Activity of Opioid Compounds Targeting the Main Protease of SARS-CoV-2

Opioids are a class of chemicals, naturally occurring in the opium poppy plant, and act on the brain to cause a range of impacts, notably analgesic and anti-inflammatory actions. Moreover, an overview was taken in consideration for SARS-CoV-2 incidence and complications, as well as the medicinal uses of opioids were discussed being a safe analgesic and anti-inflammatory drug in a specific dose. Also, our article focused on utilization of opioids in the medication of SARS-CoV-2. Therefore, the major objective of this study was to investigate the antiviral effect of opioids throughout an in silico study by molecular docking study to fifteen opioid compounds against SARS-CoV-2 main protease (PDB ID 6LU7, M^pro). The docking results revealed that opioid complexes potentially inhibit the M^pro active site and exhibiting binding energy (-11.0 kcal/mol), which is comparably higher than the ligand. Furthermore, ADMET prediction indicated that all the tested compounds have good oral absorption and bioavailability and can transport via biological membranes. Finally, M^pro-pholcodine complex was subjected to five MD (RMSD, RMSF, SASA, Rg, and hydrogen bonding) and two MM-PBSA, and conformational change studies, for 100 ns, confirmed the stability of pholcodine, as a representative example, inside the active site of M^pro.

Metal complexes of thiosemicarbazones derived by 2-quinolones with Cu(I), Cu(II) and Ni(II); Identification by NMR, IR, ESI mass spectra and in silico approach as potential tools against SARS-CoV-2

Substituted thiosemicarbazones derived by 2-quinolone were synthesized to investigate their complexation capability towards Cu(I), Cu(II) and Ni(II) salts. The structure of the complexes was established by ESI, IR and NMR spectra in addition to elemental analyses. Monodetate Cu(I) quinoloyl-substituted ligands were observed, whereas Ni(II) and Cu(II) formed bidentate-thiosemicarbazone derived by 2-quinolones. Subsequently, molecular docking was used to evaluate each analog's binding affinity as well as the inhibition constant (ki) to RdRp complex of SARS-CoV-2. Docking results supported the ability of the tested complexes that potentially inhibit the RdRp of SARSCov-2 show binding energy higher than their corresponding ligands. Additionally, ADMET prediction revealed that some compounds stratify to Lipinski's rule, indicating a good oral absorption, high bioavailability good permeability, and transport via biological membranes. Therefore, these metals-based complexes are suggested to be potentially good candidates as anti-covid agents.

5-Amino-3-methyl-Isoxazole-4-carboxylic Acid as a Novel Unnatural Amino Acid in the Solid Phase Synthesis of α/β-Mixed Peptides

The hybrid peptides consisting of α and β-amino acids show great promise as peptidomimetics that can be used as therapeutic agents. Therefore, the development of new unnatural amino acids and the methods of their incorporation into the peptide chain is an important task. Here, we described our investigation of the possibility of 5-amino-3-methyl-isoxazole-4-carboxylic acid (AMIA) application in the solid phase peptide synthesis. This new unnatural β-amino acid, presenting various biological activities, was successfully coupled to a resin-bound peptide using different reaction conditions, including classical and ultrasonic agitated solid-phase synthesis. All the synthesized compounds were characterized by tandem mass spectrometry. The obtained results present the possibility of the application of this β-amino acid in the synthesis of a new class of bioactive peptides.

Evaluation of the Binding Relationship of the RdRp Enzyme to Novel Thiazole/Acid Hydrazone Hybrids Obtainable through Green Synthetic Procedure

The viral RNA-dependent RNA polymerase (RdRp) complex is used by SARS-CoV-2 for genome replication and transcription, making RdRp an interesting target for developing the antiviral treatment. Hence the current work is concerned with the green synthesis, characterization and docking study with the RdRp enzyme of the series of novel and diverse hydrazones and pyrazoles. 4-Methyl-2-(2-(1-phenylethylidene)hydrazineyl)thiazole-5-carbohydrazide was prepared and then condensed with different carbonyl compounds (aldehydes and ketones either carbocyclic aromatic or heterocyclic) afforded the corresponding hydrazide-hydrazones. The combination of the acid hydrazide with bifunctional reagents such as acetylacetone, β-ketoesters (ethyl acetoacetate and ethyl benzoylacetate) resulted in the formation of pyrazole derivatives. The synthesized compounds were all obtained through grinding method using drops of AcOH. Various analytical and spectral analyses were used to determine the structures of the prepared compounds. Molecular Operating Environment (MOE^®) version 2014.09 was used to estimate interactions between the prepared thiazole/hydrazone hybrids and RdRp obtained from the protein data bank (PDB: 7bv2) using enzyme-ligand docking for all synthesized derivatives and Remdesivir as a reference. Docking results with the RdRp enzyme revealed that the majority of the investigated drugs bind well to the enzyme via various types of interactions in comparison with the reference drug.

Unveiling the regioselective synthesis of antiviral 5-isoxazol-5-yl-2´-deoxyuridines from the perspective of a molecular electron density theory

The regioselective synthesis of a potent antiviral sugar nucleoside isoxazole analogue in the [3+2] cycloaddition (32CA) reaction of acetonitrile- -N-oxide (ANO) and acetyl-protected 5-ethynyl-2?-deoxyuridine (EDU) has been studied at the MPWB1K/6-311G(d,p) level within perspective of the molecular electron density theory (MEDT). From an electron localization function (ELF) analysis, ANO is classified as a zwitterionic species devoid of any pseudoradical or carbenoid centre. The ortho regioisomer is energetically preferred over the meta one by the activation enthalpy of 21.7?24.3 kJ mol-1, suggesting complete regioselectivity in agreement with the experiment. The activation enthalpy increases from 53.9 kJ mol-1 in the gas phase to 71.5 kJ mol-1 in water, suggesting more facile reaction in low polar solvents. The minimal global electron density transfer (GEDT) at the TSs suggests non-polar character and the formation of new covalent bonds has not been started at the located TSs, showing non-covalent intermolecular interactions from an atoms-in- -molecules (AIM) study and in the independent gradient model (IGM) isosurfaces. The AIM analysis shows more accumulation of electron density at the C?C interacting region relative to the C?O one, and earlier C?C bond formation is predicted from a bonding evolution theory (BET) study.

Preclinical evaluation from in-silico to in-vivo study of polyherbal microsponge sunscreen gel

BACKGROUND

Electromagnetic spectrum of the UV region predominantly becomes the reason for skin's detrimental effects that give the genesis of innumerable skin ailments; because of this reason, the sunscreen products are required before condition in day to day lifestyle; products such as moisturizers, lotions, creams, shampoos, and other hair and skin preparations are accessible and accompanied by sunscreen properties, but they do not provide extended effect, also causes side effects due to harsh chemicals.

AIM

The present study focuses on the effects of polyherbal extracts containing Microsponge gel for the protection of skin from ultraviolet rays.

MATERIALS AND METHODS

In the present research, already prepared Microsponge gel through quasi-emulsion solvent diffusion (QESD) technique was used for the HPLC, in-silico, in-vitro antioxidant activity, and in-vivo study. AdmetSAR software tool was utilized for the in-silico study, whereas for the in-vivo study, UV radiations are given on Albino rats using solarimeter.

RESULTS

Results shown the active constituents are non-carcinogenic and non-toxic; IC50 values show good antioxidant activity and minimal effect of UV radiations after application of the gel formulation on animal skin.

DISCUSSION

The results manifest prominent effects on animal skin further test for presence of ascorbic acid level and total protein in blood further verify the efficacy of the formulation.

CONCLUSION

The study consequently established a strong ground for further extensive clinical studies.

Design, synthesis, biological assessment and in silico ADME prediction of new 2-(4-(methylsulfonyl) phenyl) benzimidazoles as selective cyclooxygenase-2 inhibitors

A novel series of benzimidazole derivatives wherein 4-(methylsulfonyl) phenyl pharmacophore attached via its C-2 position was designed and synthesized. These compounds were evaluated in vitro as cyclooxygenase-1(COX-1)/cyclooxygenese-2(COX-2) inhibitors. Furthermore, the synthesized compounds were also in vivo evaluated for their anti-inflammatory activity and ulcerogenic liability. Examination of histopathological lesions was also performed to evaluate the cariogenic effect of most active compounds. In silico prediction of physicochemical properties, ADME, and drug-likeness profiles were also studied. Several compounds as 11b, 11k, 12b, and 12d showed selective inhibition to (COX-2) isozyme. Compound 11b showed the most potent (COX-2) inhibitory activity with (IC₅₀ = 0.10 μM) and selectivity index (SI = 134); the tested compounds also have shown good anti-inflammatory activity. Regarding the ulcerogenic liability, compound 11b was also safest one (Ulcer Index) (UI = 0.83). The results of the molecular docking studies is closely related to the results of the in vitro COX-2 inhibitory activities.

A novel series of benzimidazole derivatives wherein 4-(methylsulfonyl) phenyl pharmacophore attached via its C-2 position was designed and synthesized.

Rapid Sequentially Palladium Catalyzed Four-Component Synthesis of Novel Fluorescent Biaryl-Substituted Isoxazoles

A series of novel 3- and 5-biaryl-substituted isoxazoles was prepared by a rapid microwave-assisted four-component three-step synthesis: concatenating Sonogashira coupling, cyclocondensation, and Suzuki coupling in a one-pot fashion. The Pd-catalyst was successfully employed in the sense of a sequentially catalyzed process, i.e., without the addition of further catalyst loading. Biaryl-substituted isoxazoles with donor–acceptor decoration possess remarkable photophysical properties, such as high fluorescence quantum yields in solution up to ΦF = 0.86 and large Stokes shifts up to 10,000 cm−1. The experimental absorption and emission characteristics can be reproduced and rationalized by computations on the DFT (density functional theory) and TDDFT (time-dependent density functional theory) level of theory.

Design, Synthesis, Molecular Docking, Antiapoptotic and Caspase-3 Inhibition of New 1,2,3-Triazole/Bis-2(1H)-Quinolinone Hybrids

A series of novel 1,2,3-triazoles hybridized with two quinolin-2-ones, was designed and synthesized through click reactions. The structures of the synthesized compounds were elucidated by NMR, IR, and mass spectra in addition to elemental analysis. The synthesized compounds were assessed for their antiapoptotic activity in testis, as testicular torsion is the main cause of male infertility. This effect was studied in light of decreasing tissue damage induced by I/R in the testis of rats using N-acetylcysteine (NAC) as an antiapoptotic reference. Compounds 6a-c were the most active antiapoptotic hybrids with significant measurements for malondialdehyde (MDA) and total antioxidant capacity (TAC) and the apoptotic biomarkers (testicular testosterone, TNFα, and caspase-3) in comparison to the reference. A preliminary mechanistic study was performed to improve the antiapoptotic activity through caspase-3 inhibition. A compound assigned as 6-methoxy-4-(4-(((2-oxo-1,2-dihydroquinolin-4-yl)oxy)methyl)-1H-1,2,3-triazol-1-yl)quinolin-2(1H)-one (6c) was selected as a representative of the most active hybrids in comparison to NAC. Assay of cytochrome C for 6c revealed an attenuation of cytochrome C level about 3.54 fold, comparable to NAC (4.13 fold). In caspases-3,8,9 assays, 6c was found to exhibit more potency and selectivity toward caspase-3 than other caspases. The testicular histopathological investigation was carried out on all targeted compounds 6a-g, indicating a significant improvement in the spermatogenesis process for compounds 6a-c if compared to the reference relative to the control. Finally, molecular docking studies were done at the caspase-3 active site to suggest possible binding modes. Hence, it could conceivably be hypothesized that compounds 6a-c could be considered good lead candidate compounds as antiapoptotic agents.

New cyanopyridine-based scaffold as PIM-1 inhibitors and apoptotic inducers: Synthesis and SARs study

Two novel series of 6-(4-benzamido-/4-phthalimido)-3-cyanopyridine derivatives were designed and synthesized as inhibitors of PIM-1 kinase. Based on cytotoxicity results via MTT assay against prostate carcinoma PC3, human hepatocellular carcinoma HepG2 and breast adenocarcinoma MCF-7 cell lines, the most potent cytotoxic cyanopyridine hits, 6, 7, 8, 12 and 13 were 1.5-3.3 times more inhibitor of cell proliferation than the reference standard, 5-FU. Selectivity profile of the latter compounds on normal human cells (WI-38), was executed, indicating that they are highly selective (IC₅₀ > 145 μM) in their cytotoxic effect. The promising compounds were further evaluated as PIM-1 kinase inhibitors. These compounds elicited remarkable inhibition of PIM-1 kinase (76.43-53.33%). Extensive studies on apoptosis were conducted for these compounds; they enhanced caspase-3 and boosted the Bax/Bcl-2 ratio 27-folds in comparison to the control. Molecular docking study of the most potent compound, 13 in PIM-1 kinase active site was consistent with the in vitro activity. Finally, prediction of chemo-informatic properties released compound 13 as the most promising ligand.

Difluoroisoxazolacetophenone: A Difluoroalkylation Reagent for Organocatalytic Vinylogous Nitroaldol Reactions of 1,2-Diketones

Difluoroisoxazolacetophenone (DFIO) is developed as a new difluoroalkylation reagent that can be easily prepared from inexpensive starting materials. In situ remote C-C bond cleavage of DFIO affords γ,γ-difluoroisoxazole nitronate that undergoes base-catalyzed vinylogous nitroaldol additions to isatins, benzothiophene-2,3-dione, unsaturated-α-ketoesters, and cyclic 1,2-diketones. This organocatalytic debenzoate vinylogous nitroaldol reaction provides a new and mild approach for the preparation of various difluoroisoxazole-substituted 3-hydroxy-2-oxindoles.

Annular oxygenation and rearrangement products of cryptotanshinone by biotransformation with marine-derived fungi Cochliobolus lunatus and Aspergillus terreus

Structural modification of natural products by biotransformation with fungi is an attractive tool to obtain novel bioactive derivatives. In the present study, cryptotanshinone (1), a quinoid abietane diterpene from traditional Chinese medicine Salvia miltiorrhiza (Danshen), was transformed by two marine-derived fungi. By using Cochliobolus lunatus TA26-46, one new oxygenated and rearranged product (2), containing a 5,6-dihydropyrano[4,3-b]chromene moiety, together with one known metabolite (10), were obtained from the converted broth of cryptotanshinone (1) with the isolated yields of 1.0% and 2.1%, respectively. While, under the action of Aspergillus terreus RA2905, seven new transformation products (3-9) as well as 10 with the fragments of 2-methylpropan-1-ol and oxygenated p-benzoquinone were produced and obtained with the isolated yields of 0.1%-1.3%. The structures of the new compounds were elucidated by comprehensive spectroscopic analysis including High Resolution Electrospray Ionization Mass Spectroscopy (HRESIMS), Nuclear Magnetic Resonance (NMR) and Electronic Circular Dichroism (ECD). The metabolic pathways of cryptotanshinone by these two fungi were presumed to be the opening and rearrangement of furan ring, and/or oxygenation of cyclohexane ring. Cryptotanshinone (1) and its metabolites displayed anti-inflammatory activities against NO production in LPS-stimulated BV-2 cells and antibacterial activities towards methicillin-resistant Staphylococcus aureus. These findings revealed the potential of marine fungi to transform the structures of natural products by biotransformation.

Quinoline-3-carboxylate Derivatives: A New Hope as an Antiproliferative Agent

BACKGROUND

The quinoline scaffold has been an attraction due to its pharmacological activities such as anti-HIV, anti-neoplastic, anti-asthmatic, anti-tuberculotic, anti-fungal, and anti-bacterial.

OBJECTIVE

The designed quinoline-3-carboxylate derivatives were synthesized through a two-step reaction and evaluated for antiproliferative activity against MCF-7 and K562 cell lines.

METHODS

Synthesized compounds were characterized by modern analytical techniques like NMR, 2DNMR, mass, and IR. Moreover, the purity of compounds was analyzed through the HPLC. In the progress of biological results, all synthesized compounds were evaluated for antiproliferative activity against MCF-7 and K562 cell lines.

RESULTS

The synthesized compounds exhibited micromolar inhibition in all over the ranges, however, some of the compounds showed better activity than the standard anticancer drug such, as 4m and 4n with the IC50 value of 0.33μM against the MCF-7 cell line, and the compounds 4k and 4m showed potential activity against the K562 cell line with the IC50 value of 0.28μM. The anti-cancer activities of compounds were found to be through the up-regulation of intrinsic apoptosis pathways.

CONCLUSION

The biological data of all compounds in both cell lines were utilized for the structural activity relationship of the quinoline-3-carboxylate pharmacophore. The active lead was further validated through rigorous in silico studies for the drug-likeness (QED) and Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) properties. Here in the present research is utilized for the demonstration of an important pharmacophore, which could be utilized for further development to become a lead as an anticancer agent with minimal toxicity.

Design, synthesis, mechanistic studies and in silico ADME predictions of benzimidazole derivatives as novel antifungal agents

Herein, novel three series of benzimidazole scaffold bearing hydrazone, 1,2,4-triazole and 1,3,4-oxadiazole moieties 1-3, 4a-j, 6a-c and 7 derivatives were designed, synthesized and evaluated for their antimicrobial activity. The structures of the prepared compounds were assigned using different spectroscopic techniques such as IR, ¹H NMR, ¹³C NMR and elemental analyses. Compounds 3, 4a, 4e and 4f exhibited remarkable antifungal activity against C. albicans and C. neoformans var. grubii with MIC values ranging from 4 to 16 μg/mL. Furthermore, they were not cytotoxic against red blood cells and human embryonic kidney cells at concentration up to 32 μg/mL. The study was expanded to forecast the mechanism of action of the prepared compounds and determine sterol quantitation method (SQM) by spectrophotometric assay. On the other hand, compound 4e showed the highest inhibitory activity against lanosterol 14α-demethylase (CYP51) with IC₅₀ value = 0.19 μg/mL compared to fluconazole as reference IC₅₀ value = 0.62 μg/mL. Also, compounds 4d and 4f exhibited mild to moderate antibacterial activity. Moreover, molecular docking of the active target compound 4e in active site of lanosterol 14α-demethylase (CYP51) revealed that docking scores and binding mode are comparable to that of co-crystallized ligand confirming their antifungal activity. In silico ADME prediction investigations also forecasting the drug-like characters of these compounds.

Synthesis, Molecular Properties Prediction and Antimicrobial Activity of Imidazolyl Schiff Bases, Triazoles and Azetidinones

Benzylidenehydrazinyl imidazoles (3) are prepared from 2-hydrazinyl imidazoles (2) on treatment with hydrazine. The imine functionality in 3 is utilized to develop 5'-aryl-N-(4-aryl-1H-imidazol-2-yl)-1H-1,2,3-triazol-1-amines (5) by 1,3-dipolar cycloaddition of diazomethane followed by aromatization with I₂ in DMSO. Compounds 3 are also explored to prepare 4'-aryl-1-(4-aryl-1H-imidazol-2-ylamino)-3-chloroazetidin-2-ones (6) on treatment with chloroacetyl chloride. The Molinspiration calculations predicted that 3, 5 and 6 have molecular hydrophobicity, conformational flexibility, good intestinal absorption and bioactivity scores. The chloro, bromo and nitro substituted imidazolyl azetidinones (6c, 6d, 6f) and nitro substituted imidazolyl triazole (5f) exhibited excellent antibacterial activity on B. subtilis, whereas chloro and nitro substituted imidazolyl triazoles (5c, 5f) showed prominent antifungal activity on A. niger.

The synthetic and therapeutic expedition of isoxazole and its analogs

Isoxazole, constituting an important family of five-membered heterocycles with one oxygen atom and one nitrogen atom at adjacent positions is of immense importance because of its wide spectrum of biological activities and therapeutic potential. It is, therefore, of prime importance that the development of new synthetic strategies and designing of new isoxazole derivatives should be based on the most recent knowledge emerging from the latest research. This review is an endeavor to highlight the progress in the chemistry and biological activity of isoxazole derivatives which could provide a low-height flying bird's eye view of isoxazole derivatives to the medicinal chemists for the development of clinically viable drugs using this information.