Synthesis of novel 2,3‐disubstituted quinazolin‐4(3H)‐one derivatives containing hydrazone skeleton as potent urease inhibitors and their antimicrobial activities

A new series of quinazolinones containing hydrazone moiety were synthesized, and their inhibitory activities on urease were assessed in vitro. Most of the compounds exhibited potent urease inhibitory activity. Among the synthesized compounds, molecule 4a bearing furan ring has the best inhibitory effect against urease with IC₅₀ = 2.90 ± 0.11 μg/mL. Compounds 4f , 4g , 4h , 4i , and 4j have hydroxy group on phenyl ring. Compound 4i is the most active inhibitor among these compounds with IC₅₀ = 5.01 ± 0.10 μg/mL, which has 3‐Cl and 4‐Br on phenyl ring. Also, newly synthesized compounds had been tested for their antimicrobial effects against three of Gram‐positive bacteria (Bacillus cereus 702 Roma, Staphylococcus aureus ATCC 25923, and Streptococcus pyogenes ATCC 19615) and three of Gram‐negative bacteria (Escherichia coli ATCC 25922, Proteus vulgaris ATCC 13315, and Pseudomonas aeruginosa ATCC 27853). Antimicrobial activity results show that compounds 4a , 4h , 4j , 4f , and 4l have the lowest minimum inhibitory concentration (MIC) value of 1000 μg/mL to all tested bacteria. The other compounds have the MIC value of >1000 μg/mL to all tested bacteria.     

Microwave‐Assisted Synthesis and Antituberculosis Screening of Some 4‐((3‐(Trifluoromethyl)‐5,6‐dihydro‐[1,2,4]triazolo[4,3‐a]pyrazin‐7(8H)‐l)methyl)benzenamine Hybrids

In the present investigation, a series of 4‐((3‐(trifluoromethyl)‐5,6‐dihydro‐[1,2,4]triazolo[4,3‐a]pyrazin‐7(8H)‐yl)methyl)benzenamine analogs 6a–o were synthesized and characterized by IR, NMR (¹H and ¹³C), and mass spectra. All newly synthesized compounds 6a–o were prepared under conventional and microwave irradiation methods. These compounds obtained in higher yields and in shorter reaction times in the microwave irradiation method when compared with the conventional method. Synthesized compounds 6a–o were inspected for their in vitro antitubercular activity against Mycobacterium tuberculosis H₃₇Ra using an established XTT reduction menadione assay. Among the screened compounds, 6i (IC₅₀: 1.82 μg/mL), 6j (IC₅₀: 1.02 μg/mL), and 6k (IC₅₀: 1.59 μg/mL) showed excellent activity. Furthermore, compound 6i showed MIC₉₀ value of 16.02 μg/mL. In summary, the results indicate the identification of some novel, selective, and specific inhibitors against M. tuberculosis that can be explored further for the potential antitubercular drug.     

Synthesis,Antimicrobial, and Anticancer Activities of a New Series of Thieno[2,3‐d] Pyrimidine Derivatives

A new series from thieno[2,3‐d] pyrimidine derivatives have been synthesized based on 2‐(ethylmercapto)‐4‐mercapto‐6‐phenyl‐5‐pyrimidine carbonitrile, these compounds used in the synthesis of many pyrimidothienopyrimidine derivatives and triazolo[1″,5″:1″,6″]pyrimido[4′,5′:4,5]thieno[2,3‐d] pyrimidine derivatives. The chemical composition of these compounds was confirmed by ¹H NMR, ¹³C NMR, and MS techniques. Some of the synthesized compounds were screened for their antimicrobial and anticancer agent. Compound ( 9b ) showed strong effect on Aspergillus Fumigatus (RCMB 2568), Candida albicans (RCMB 05036), Saphylococcus aureus (RCMB 010010), Bacillis subtilis (RCMB 010067), Salmonella sp. (RCMB 010043), and Escherichia coli (RCMB 010052). Compounds ( 2 ) and ( 5a – k ) were evaluated for their IC₅₀ values against two cancer cell lines (MCF‐7 and HeLa cells) in the presence of Paclitaxel as reference material. Compound ( 5g ) showed the highest cytotoxicity against MCF‐7 (IC₅₀ values about 18.87 ± 0.2 μg/mL) cells compared with Paclitaxel (IC₅₀ values about 40.37 ± 1.7 μg/mL). Also, compound ( 5d ) showed the highest cytotoxicity against HeLa (IC₅₀ values about 40.74 ± 1.7 μg/mL) cells compared with Paclitaxel (IC₅₀ values about 45.78 ± 0.8 μg/mL).     

Synthesis,in vitro urease inhibitory activity and molecular docking of 3,5‐disubstituted thiadiazine‐2‐thiones

A series of 3,5‐disubstituted‐tetrahydro‐thiadiazine‐2‐thione ( 1 ‐ 16 ) have been synthesized, characterized by elemental analysis, infrared (IR), UV‐visible, ¹H NMR, ¹³C NMR, and MS spectroscopic techniques, and screened against jack bean urease. Among 16 compounds, compounds ( 1 ), ( 2 ), ( 3 ), ( 4 ), ( 6 ), ( 7 ), and ( 9 ) demonstrated excellent urease inhibitory activity with IC₅₀ values (9.8 ± 0.5, 11.0 ± 0.6, 16.0 ± 1.5, 17.2 ± 0.5, 15.4 ± 0.5, 19.7 ± 0.4, and 15.8 ± 0.2μM), respectively, even better than the standard thiourea (IC₅₀ = 21 ± 0.01μM). However, compound ( 8 ) shows an almost same level of inhibition (IC₅₀ = 22.9 ± 0.3μM), as like standard. In this work, we reported for the first time urease inhibitory activity of thiadiazine thiones and its molecular docking studies.     

Evaluation of newly synthesized derivatives of bis(hydrazine‐1‐carbothioamide) and their metal complexes synthesized in bulk and nano size as potent anticancer agents

A series of new metal complexes were synthesized in both bulk and nano size using green methods, starting with the reaction of (E)‐N′‐[(E)‐2‐bromobenzylidene]‐4‐oxo‐4‐(piperidin‐1‐yl)but‐2‐enehydrazide with thiosemicarbazide and different metal halides such as CuI·2H₂O, CuCl₂·2H₂O, CoCl₂·2H₂O, and ZnCl₂·2H₂O, and metal nitrate such as Ga(NO₃)₃·2H₂O. Structures of these metal complexes were confirmed using different spectroscopic methods, elemental analysis, electronic spectra, and microanalytical methods (scanning electron microscopy and transmission electron microscopy) for nano complexes. The distorted octahedral geometry for all complexes was suggested based on magnetic moments and electronic spectral studies. The cytotoxic activity of the compounds was investigated against human hepatocellular carcinoma (HepG2) and human colorectal carcinoma (HCT‐116) cell lines. Most tested compounds had higher inhibitory activity than the standard vinblastine drug. Interestingly, the nano‐sized Ga(III) complex 11 was the most potent compound against the two tested cell lines, with 50% inhibitory concentration (IC₅₀) of 2.56 μg/mL for HepG2, compared with the reference drug vinblastine (IC₅₀ 15.6 μg/mL), and IC₅₀ 4.64 μg/mL for HCT‐116, compared with the standard (IC₅₀ 13.9 μg/mL). The bioassay results helped us identify new potent and selective anticancer agents.     

Large‐scale separation of acetylcholinesterase inhibitors from Zanthoxylum nitidum by pH‐zone‐refining counter‐current chromatography target‐guided by ultrafiltration high‐performance liquid chromatography with ultraviolet and mass spectrometry screening

A new strategy by converging ultrafiltration high‐performance liquid chromatography with ultraviolet and mass spectrometry and pH‐zone‐refining counter‐current chromatography was developed for the rapid screening and separation of potential acetylcholinesterase inhibitors from the crude alkaloidals extract of Zanthoxylum nitidum. An optimized two‐phase solvent system composed of chloroform/methanol/water (4:3:3, v/v) was used in this study. And, in the optimal solvent system, 45 mM hydrochloric acid was added to the aqueous stationary phase as the retainer, while 5 mM triethylamine was added to the organic mobile phase as the eluter. As a result, with the purity of over 95%, five alkaloids including jatrorrhizine ( 1 , 340 mg), columbamine ( 2 , 112 mg), skimmianine ( 3 , 154 mg), palmatine ( 4 , 226 mg), and epiberberine ( 5 , 132 mg) were successfully purified in one step from 3.0 g crude alkaloidals extract. And their structures were identified by ultraviolet, mass spectrometry, ¹H and ¹³C NMR spectroscopy. Notably, compounds 2 , 4 and 5 were firstly reported in Z. nitidum. In addition, acetylcholinesterase inhibitory activities of compounds 1–5 were evaluated, and compounds 3, 4 and 5 exhibited stronger acetylcholinesterase inhibitory activity (IC₅₀ values at 8.52 ± 0.64, 14.82 ± 1.21 and 3.12 ± 0.32 μg/mL, respectively) than berberine (IC₅₀ value at 32.86 ± 2.14 μg/mL, positive control). The results indicated that the proposed method is an efficient technique to rapidly screen acetylcholinesterase inhibitors from complex samples, and could be served as a large‐scale preparative technique for separating ionizable active compounds.     

A Facile One‐pot Synthesis and Anticancer Evaluation of Interesting Pyrazole and Pyrimidinthione via Heterocyclic Interconversion

Design and synthesis of new pyrazole, pyrimidinthione, and triazepinthione derivatives via heterocyclic ring opening of azacoumarin were promoted with grinding and ultrasonic reaction conditions. Efficient solventless one‐pot synthesis can be well progressed to afford the good yield of new heterocyclic products that were characterized by IR, ¹H‐NMR, MS, and microanalytical data. Anticancer evaluation for the synthesized compounds exhibited moderate to good cytotoxicity such as pyrazole derivatives 5 , 9 , and 14 that displayed best cytotoxic activities with IC₅₀ 8.16 ± 1.1, 7.02 ± 0.6, and 5.12 ± 0.41 μg/mL and 9.28 ± 0.7, 6.45 ± 0.9, and 5.85 ± 0.26 μg/mL for MCF‐7 and WI cells, respectively. Pyrimidine derivatives 6 , 11 , and 15 exhibited strong cytotoxicity with IC₅₀ 8.9 ± 0.62, 7.16 ± 0.5, and 7.72 ± 0.41 μg/mL against MCF‐7.     

Synthesis,in vitro Antimicrobial,and Cytotoxic Activities of New 1,3,4‐Oxadiazin‐5(6H)‐one Derivatives from Dehydroabietic Acid

A series of new 1,3,4‐oxadiazin‐5(6H)‐one derivatives ( 6a–n ) of dehydroabietic acid were designed and synthesized as potential antimicrobial and antitumor agents. Their structures were characterized by IR, ¹H NMR, ¹³C NMR, MS, and elemental analyses. All the title compounds were evaluated for their antimicrobial activity against four bacterial and three fungal strains using the serial dilution method. Among them, compound 6e showed the highest antibacterial activity against Bacillus subtilis with a minimum inhibitory concentration (MIC) value of 1.9 μg/mL. In addition, the in vitro cytotoxic activities of the title compounds were also assayed against three human carcinoma cell lines (MCF‐7, SMMC‐7721, and HeLa) through the MTT colorimetric method. As a result, compounds 6b , 6g , 6k, and 6m exhibited significant inhibition against at least one cell line with IC₅₀ values below 10 μM. Compound 6m was especially found to be the most potent derivative with IC₅₀ values of 2.26 ± 0.23, 0.97 ± 0.11, and 1.89 ± 0.31 μM against MCF‐7, SMMC‐7721, and HeLa cells, respectively, comparable to positive control etoposide.     

Novel 5‐Methyl‐2‐[(un)substituted phenyl]‐4‐{4,5‐dihydro‐ 3‐[(un)substituted phenyl]‐5‐(1,2,3,4‐tetrahydroisoquinoline‐2‐yl)pyrazol‐1‐yl}‐oxazole Derivatives: Synthesis and Anticancer Activity

Eleven novel 5‐methyl‐2‐[(un)substituted phenyl]‐4‐{4,5‐dihydro‐3‐[(un)substituted phenyl]‐5‐(1,2,3,4‐tetrahydroisoquinoline‐2‐yl)pyrazol‐1‐yl}‐oxazole derivatives were synthesized and characterized by elemental analysis, ESI‐MS, ¹H NMR and ¹³C NMR. All of the compounds have been screened for their antiproliferative activities against PC‐3 cell (human prostate cancer) and A431 cell (human epidermoid carcinoma cancer) lines in vitro. The results revealed that compounds 4g , 4j and 4k exhibited the strong inhibitory activities against the PC‐3 cell lines (with IC₅₀ values of 2.8±0.11, 3.1±0.10 and 3.0±0.06 μg/mL, respectively).     

Design,Synthesis and Antifungal Evaluation of N‐Substituted‐1‐(3‐chloropyridin‐2‐yl)‐N‐(pyridin‐4‐yl)‐5‐(trifluoromethyl)‐1H‐pyrazole‐4‐carboxamide Derivatives

A series of 1‐(3‐chloropyridin‐2‐yl)‐5‐(trifluoromethyl)‐1H‐pyrazole‐4‐carboxamide derivatives which have di‐substituents on nitrogen were designed and synthesized. Bioassay results showed that all the synthetic compounds exhibited lower antifungal activities against Gibberella zeae, Cytospora mandshurica, and Fusarium oxysporum than T ₃ (14.7, 21.1, and 32.7 μg/mL), but some of them exhibited better activities against Botrytis cinerea, Phytophthora infestans, and Sclerotinia sclerotiorum than T ₃ (>200, >200, and >200 μg/mL); the EC₅₀ values of 7d and 7c against B. cinerea were 94.9 and 56.2 μg/mL, respectively. The EC₅₀ values of 7a , 7d , and 7c against S. sclerotiorum were 73.5, 78.7, and 68.5 μg/mL, respectively.     

4‐Chlorothiazole‐5‐carbaldehydes as Potent Precursors for Synthesis of Some New Pendant N‐heterocyces Endowed with Anti‐Tumor Activity

In our approach to synthesize bioactive molecules, a series of novel N‐heterocycles were synthesized and evaluated for their in vitro antitumor activity against a panel of three human cancer cell lines, namely, human breast cancer cell line (MCF‐7), human cervical cancer cell line (HeLa), and human prostate cancer PC‐3. The majority of the tested compounds exhibited significant cytotoxic activity toward the tested tumor cell lines. Analogues 33 , 34 , 31 , 38 , 21 , 23 , 22 , and 20 exhibited considerable cytotoxic activities comparable with standard drug 5‐fuorouracil. Compound 33 displayed superior cytotoxicity with IC₅₀ value of 4.12 ± 1.21 μg/mL against HeLa tumor cell line.     

Synthesis and Ameliorative Effect of Isatin–Mesalamine Conjugates on Acetic Acid‐induced Colitis in Rats

A series of new isatin–mesalamine conjugates ( 9a – g ) were synthesized via conjugation of isatin ( 3a ) and its derivatives ( 3b – 3d , 4 , 5 , and 6 ) with mesalamine ( 7 ) by using chloroacetyl chloride as a bifunctional linker. Compounds 3a – 3d were prepared by employing Sandmeyer reaction. Compounds 4 , 5 , and 6 were obtained from isatin ( 3a ) via previously reported methods. The synthesized compounds were characterized by IR, mass, ¹H NMR, and ¹³C NMR spectral techniques. Synthesized compounds ( 3a – d , 4 , 5 , 6 , and 9a – g ) were evaluated for in vitro antioxidant activity by DPPH assay method using ascorbic acid as standard. Hybrids 9b (IC₅₀ = 368.6 ± 3.5 μM) and 9f (IC₅₀ = 335.1 ± 2.9 μM) showed better antioxidant activity than its parent compounds such as 3a (IC₅₀ = 556.8 ± 2.9 μM), 5 (IC₅₀ = 511.9 ± 3.6 μM), and 7 (IC₅₀ = 768.9 ± 2.7 μM). Acetic acid‐induced ulcerative colitis in rat model was chosen to examine the antioxidant potential of the synthesized hybrids ( 9b and 9f ) in the amelioration of ulcerative colitis. Colonic myeloperoxidase and malondialdehyde enzymes were used as biomarkers of anti‐ulcerative colitis activity. In the present study, hybrids 9b and 9f reduced the levels of colonic myeloperoxidase and malondialdehyde enzymes significantly (p < 0.05) when compared with control (colitic), at a dose (0.03 mM/12.5 mg/kg b.w. p.o.) (50%) less than that of its parent moieties mesalamine (0.16 mM/25 mg/kg) and isatin (0.16 mM/25 mg/kg). Thus, the molecular hybridization was proved to be significant in enhancing the activity of hybrids 9b and 9f by reducing the dose.     

Design,synthesis of (Z)‐3‐benzyl‐5‐((1‐phenyl‐3‐(3‐((1‐ substituted phenyl‐1H‐1,2,3‐triazol‐4‐yl)methoxy)phenyl)‐1H‐pyrazol‐4‐yl)methylene)thiazolidine‐2,4‐dione analogues as potential cytotoxic agents

In an attempt to achieve promising cytotoxic agents, a series of new (Z)‐3‐benzyl‐5‐((1‐phenyl‐3‐(3‐((1‐substituted phenyl‐1H‐1,2,3‐triazol‐4‐yl)methoxy)phenyl)‐1H‐pyrazol‐4‐yl)methylene)thiazolidine‐2,4‐diones 10 a‐n were designed, synthesized, and characterized by ¹H NMR, ¹³C NMR, IR, and ESI‐MS techniques. These compounds synthesized from appropriate reaction procedures with better yields. All the novel synthesized compounds 10a‐n were evaluated for their cytotoxic activity against the MCF‐7 cell line (Human breast cancer cell line) at different concentrations of 0.625, 1.25, 2.5, 5, and 10 μM, respectively. The cytotoxic evaluation assay is presented in terms of IC₅₀ values and percentage cell viability reduction compared against standard drug cisplatin. Among all novel synthesized compounds 10a‐n , some of the representative analogues particularly 10g and 10e exhibit remarkable cytotoxic activity with IC₅₀ values 0.454 and 0.586 μM, comparable to that of the standard drug cisplatin, and some analogues 10d , 10f , 10k, and 10m also have shown significant activity.     

Synthesis,characterization, and hypoglycemic efficacy of nitro and amino acridines and 4-phenylquinoline on starch hydrolyzing compounds: an in silico and in vitro study

α-Amylase and α-Glucosidase are important therapeutic targets for type II diabetes. The present focus of our study is to elucidate the hypoglycemic activity of novel compounds through in vitro and in silico studies. Here, we synthesized the nitro acridines (3a–3c), amino acridines (4a–4c), and nitro phenylquinoline (3d) and amino phenylquinoline (4d) using a multi-step reaction protocol in good yields. All the above derivatives were screened for molecular docking, α-Amylase and α-Glucosidase inhibitory activities utilizing acarbose as standard drug. In silico studies were performed to explore the binding ability of compounds with the active site of α-Amylase and α-Glucosidase enzymes. The in vitro antihyperglycemic report of 3c exhibits the maximum inhibitory activity with IC₅₀ values of 200.61?±?9.71 μmol/mL and 197.76?±?8.22 μmol/mL against α-Amylase and α-Glucosidase, respectively. Similarly, the compound 3a exhibits IC₅₀ values of 243.78?±?13.25 μmol/mL and 296.57?±?10.66 μmol/mL, and 4c exhibits IC₅₀ values of 304.28?±?3.51 μmol/mL and 278.86?±?3.24 μmol/mL with a significant p?<?0.05 in both enzyme inhibitions. In addition, the presence of diverse functional moieties in synthesized compounds may provide a strong inhibitory action against the abovementioned enzymes compared with standard acarbose inhibition (IC₅₀, 58.74?±?3.68 μmol/mL and 49.39?±?4.94 μmol/mL). Also, the docking studies provided an excellent support for our in vitro studies. The outcome of these studies recommends that the tested compounds might be treated as potential inhibitors for the starch hydrolyzing enzymes in type II diabetes.

     

Synthesis and antitumor evaluation of some new derivatives and fused heterocyclic compounds derived from thieno[2,3‐b]pyridine

On the basis of the proven activity of thieno[2,3‐b]pyridines as anticancer, we have designed to synthesize a novel several heterocyclic compounds utilizing thieno[2,3‐b]pyridine as a skeleton through various chemical reactions. The synthesized compounds bear rings that are either directly attached to the thieno[2,3‐b]pyridine as in compounds 4 to 6 and 9 or connected through an amide bridge as compounds 2 , 3a ‐ b , 7 , and 8 . As well as, compounds 10 , 12 to 28 , 30 , 31 , and 33 to 36 bear fused rings to the thieno[2,3‐b]pyridine backbone. The newly synthesized compounds were screened for their antiproliferative activity in vitro against hepatocellular carcinoma (HepG‐2) and breast cancer (MCF‐7) compared with the standard drug (doxorubicin). Compounds 3b , 4 , 6 , 22 , and 28 exhibited promising growth inhibitory effect toward both HepG‐2 and MCF‐7 cell lines with IC₅₀ values ranging from 5.88 to 11.70 μg/mL and 9.64 to 15.10 μg/mL, respectively.     

GC-MS analysis of metabolites from soxhlet extraction,ultrasound-assisted extraction and supercritical fluid extraction of Salacca zalacca flesh and its alpha-glucosidase inhibitory activity

Abstract

Different extraction processes were employed to extract bioactive metabolites from Salacca zalacca flesh by a range of aqueous and organic solvents. The highest extraction yield was obtained by 50% ethanol extract of SE (73.18?±?4.35%), whereas SFE_1 showed the lowest yield (0.42?±?0.08%). All extracts were evaluated for in vitro α-glucosidase inhibitory activity, measured by their IC₅₀ values in comparison to that of quercetin, the positive control (IC₅₀ = 2.7?±?0.7?μg/mL). The lowest α-glucosidase inhibitory activity was indicated by water extract of SE (IC₅₀ = 724.3?±?42.9?μg/mL) and the highest activity was demonstrated by 60% ethanol extract by UAE (IC₅₀ = 16.2?±?2.4?μg/mL). All extracts were analysed by GC-MS and identified metabolites like carbohydrates, fatty acids, organic acids, phenolic acids, sterols and alkane-based compounds etcetera that may possess the potential as α-glucosidase inhibitor and may attribute to the α-glucosidase inhibitory activity.     

An Expedient Method for the Synthesis of 1,2,4‐Triazolo‐fused 1,5‐Benzodiazepine, 1,5‐Benzoxazepine,and 1,5‐Benzothiazepine Scaffolds: A Novel Seven‐membered Ring System of Biological Interest

New heterocyclic compounds 1‐(3‐methyl‐9H‐dibenzo[b,f][1,2,4]triazolo[4,3‐d][1,4]diazepin‐6‐yl)ethanone 8a , 1‐(3‐methyldibenzo[b,f][1,2,4]triazolo[4,3‐d][1,4]oxazepin‐6‐yl)ethanone 8b , and 1‐(3‐methyldibenzo[b,f][1,2,4]triazolo[4,3‐d][1,4]thiazepin‐6‐yl)ethanone 8c are synthesized from benzodiazepinone, benzoxazepinone, and benzothiazepinone derivatives. These heterocyclic scaffolds have wide medicinal importance. Best results were obtained in antibacterial screening against Escherichia coli, Enterobacter cloacae, and Staphylococcus aureus and antifungal screening against Candida albicans and Fusarium oxysporum. 1,1‐Diphenyl‐2‐picrylhydrazyl radical scavenging activities of compounds 6c , 7c , and 8c were tested in doses 10, 20, 30, 40, and 50 μg/mL and were expressed as IC₅₀ values and percent of inhibition with means ± standard deviation of three different concentrations of synthesized compounds. The assignment of the structures of synthesized compounds was made by thin‐layer chromatography, elemental analysis, IR, ¹H‐NMR, ¹³C‐NMR, and liquid chromatography–mass spectrometry.     

Synthesis of Substituted Quinolinyl Ether‐based Inhibitors of PI3K as Potential Anticancer Agents

A new strategy for the preparation of 8‐quinolyl ethers 3 ( a – g ), 5 ( a – g ), and 7 ( a – d ) was studied by copper (II)‐catalyzed methodology in the presence of Cs₂CO₃ and acetone–water mixture (1:1). Screening of quinolinyl‐8‐ethers was investigated against anticancer expressive studies to validate new chemical entity in medicinal chemistry. Approaches were evaluated against breast cancer (MCF‐7), skin cancer (G‐361), and colon cancer (HCT 116) cell lines. Inhibitory potentials against phosphoinositide‐3‐kinase (PI3K) enzyme responsible for cancer development have been evaluated by competitive ELISA studies. In PI3K assay, 3a – c were inactive (IC₅₀ > 5 μM), while 3e – g , 5a , 5c – e , 5g , 7a , and 7d showed a moderate activity (IC₅₀ ≥ 0.05 μM). Compounds ( 5b , 5f , 7b , and 7c ) showed significant activity (IC₅₀ < 1.0 μM); thus, their anticancer activities were carried out. Anticancer activity was found to be selective towards breast cancer (MCF‐7); 5b , 5f , 7b , and 7c showed predominant relative percentage activities of 74.12%, 79.04%, 72.56%, and 78.47%, with IC₅₀ values of 5b (2.27 ± 0.88 μM), 5f (1.38 ± 0.60 μM), 7b (2.64 ± 0.86 μM), and 7c (1.87 ± 0.68 μM) compared with the standard doxorubicin 73.14% inhibition (IC₅₀ = 1.98 ± 0.75 μM). Docking study also conducted to find out the binding interactions with p110α (PDB ID: 3T8M) enzyme. Compounds 5b , 5f , 7b , and 7c showed best docking score into the active site of PI3K 12.59, 10.51, 56.52, and 8.61 nM. Structure–activity relationship studies demonstrated that the synthesized compounds are the potential PI3K inhibitors to treat various cancer‐related diseases.     

Synthesis,spectral, structural characterization and biological activity of new palladium(II) complexes containing 3‐acetyl‐8‐methoxy‐2H‐chromen‐2‐one derived Schiff bases

Four different mononuclear palladium(II) complexes of 3‐acetyl‐8‐methoxycoumarin Schiff bases were synthesized and characterized by spectrochemical techniques. Further analysis through X‐ray crystallography confirmed the structures of the complexes. Their interactive ability with Calf Thymus DNA and protein (Bovine Serum Albumin and Human Serum Albumin) were investigated by means of absorption and emission methods. The intercalative mode of binding with DNA was supported by EB displacement studies and viscosity measurements. Configurational changes that occurred in the proteins have been analysed with the help of 3D fluorescence studies. The complexes were shown to have good antimicrobial activity against the tested bacterial and fungal pathogens. In addition, antiproliferative activity of the complexes was evaluated on A549 and MCF‐7 cell lines and the complexes were comparatively more active than the standard drug cisplatin. Among the compounds, complex 3 was the most effective against MCF‐7 (IC₅₀ value of 5.20 ± 0.15 μM) and A549 (5.09 ± 0.13 μM) compared with the other complexes 1 (6.48 ± 0.17 μM; 5.98 ± 0.09 μM), 2 (5.53 ± 0.12 μM; 5.85 ± 0.11 μM), 4 (6.73 ± 0.19 μM; 6.63 ± 0.16 μM) and cisplatin (16.79 ± 0.08 μM; 15.10 ± 0.05 μM) respectively. LDH and NO release assays confirmed the cytotoxic potential of the synthesized complexes.     

Physiochemical properties and novel biological applications of Callistemon viminalis‐mediated α‐Cr2O3 nanoparticles

We report an eco‐friendly synthesis of α‐Cr₂O₃ nanoparticles (NPs) using Callistemon viminalis (Bottle Brush) flower extracts as an efficient reducing and capping agent. NPs of sizes 15 nm and 17 nm were synthesized by annealing them at 400°C and 500°C, respectively, which were characterized by X‐ray diffraction, UV–Vis, Fourier transform‐infrared, high‐resolution‐transmission electron microscopy/scanning electron microscopy, SAED, energy‐dispersive X‐ray spectroscopy and SQUID. Microplate‐based assay was used for examining antibacterial potential against 12 pathogenic bacterial strains, and their minimum inhibitory concentrations were calculated. MTT cytotoxic assay was accomplished on Leishmania tropica amastigotes and promastigotes, which revealed IC₅₀ values of 44 μg/ml and 10.56 μg/ml, respectively. An IC₅₀ value of 46.32 μg/ml was obtained for HepG2 cancer cells. Enzyme inhibition studies indicated good acetylcholinesterase, moderate butyrylcholinesterase and low alpha‐glucosidase inhibition. Hemolytic assay indicated hemocompatibility at low concentration. In addition, good DPPH radical scavenging and moderate reducing power and total antioxidant potential was revealed by α‐Cr₂O₃ NPs.