The β-glucuronidase, a lysosomal enzyme, catalyzes the cleavage of glucuronosyl-O-bonds. Its inhibitors play a significant role in different medicinal therapies as they cause a decrease in carcinogen-induced colonic tumors by reducing the level of toxic substances present in the intestine. Among those inhibitors, bisindole derivatives had displayed promising β-glucuronidase inhibition activity. In the current study, hydrazone derivatives of bisindolymethane (1-30) were synthesized and evaluated for in vitro β-glucuronidase inhibitory activity. Twenty-eight analogs demonstrated better activity (IC50 = 0.50-46.5 µM) than standard D-saccharic acid 1,4-lactone (IC50 = 48.4 ± 1.25 µM). Compounds with hydroxyl group like 6 (0.60 ± 0.01 µM), 20 (1.50 ± 0.10 µM) and 25 (0.50 ± 0.01 µM) exhibited the most potent inhibitory activity, followed by analogs with fluorine 21 (3.50 ± 0.10 µM) and chlorine 23 (8.20 ± 0.20 µM) substituents. The presence of hydroxyl group at the aromatic side chain was observed as the main contributing factor in the inhibitory potential. From the docking studies, it was predicted that the active compounds can fit properly in the binding groove of the β-glucuronidase and displayed significant binding interactions with essential residues.
In the title benzoyl-hydrazide derivative, C17H18N2O, the dihedral angle between the benzene rings is 88.45 (8)° and the azomethine double bond adopts an E conformation. In the crystal, mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen bonds, forming a chain along the b axis.
Diabetes is associated with neurodegeneration. Glycation ensues in diabetes and glycated proteins cause insulin resistance in brain resulting in amyloid plaques and NFTs. Also glycation enhances gliosis by promoting neuroinflammation. Currently there is no therapy available to target neurodegenration in brain therefore, development of new therapy that offers neuroprotection is critical. The objective of this study was to evaluate mechanistic effect of isatin derivative URM-II-81, an anti-glycation agent for improvement of insulin action in brain and inhibition of neurodegenration. Methylglyoxal induced stress was inhibited by treatment with URM-II-81. Also, Ser473 and Ser9 phosphorylation of Akt and GSK-3β respectively were restored by URM-II-81. Effect of URM-II-81 on axonal integrity was studied by differentiating Neuro2A using retinoic acid. URM-II-81 restored axonal length in MGO treated cells. Its effects were also studied in high fat and low dose streptozotocin induced diabetic mice where it reduced RBG levels and inhibited glycative stress by reducing HbA1c. URM-II-81 treatment also showed inhibition of gliosis in hippocampus. Histological analysis showed reduced NFTs in CA3 hippocampal region and restoration of insulin signaling in hippocampii of diabetic mice. Our findings suggest that URM-II-81 can be developed as a new therapeutic agent for treatment of neurodegenration.
Current study based on the synthesis of new thiazole derivatives via "one pot" multicomponent reaction, evaluation of their in vitro α-glucosidase inhibitory activities, and in silico studies. All synthetic compounds were fully characterized by (1)H NMR, (13)C NMR and EIMS. CHN analysis was also performed. These newly synthesized compounds showed activities in the range of IC50=9.06±0.10-82.50±1.70μM as compared to standard acarbose (IC50=38.25±0.12μM). It is worth mentioning that most of the compounds such as 1 (IC50=23.60±0.39μM), 2 (IC50=22.70±0.60μM), 3 (IC50=22.40±0.32μM), 4 (IC50=26.5±0.40μM), 6 (IC50=34.60±0.60μM), 7 (IC50=26.20±0.43μM), 8 (IC50=14.06±0.18μM), 9 (IC50=17.60±0.28μM), 10 (IC50=27.16±0.41μM), 11 (IC50=19.16±0.19μM), 12 (IC50=9.06±0.10μM), 13 (IC50=12.80±0.21μM), 14 (IC50=11.94±0.18μM), 15 (IC50=16.90±0.20μM), 16 (IC50=12.60±0.14μM), 17 (IC50=16.30±0.29μM), and 18 (IC50=32.60±0.61μM) exhibited potent inhibitory potential. Molecular docking study was performed in order to understand the molecular interactions between the molecule and enzyme. Newly identified α-glucosidase inhibitors except few were found to be completely non-toxic.
3-Thiazolylcoumarin derivatives 1-14 were synthesized via one-pot two step reactions, and screened for in vitro α-glucosidase inhibitory activity. All compounds showed inhibitory activity in the range of IC50 = 0.12 ± 0.01-16.20 ± 0.23 μM as compared to standard acarbose (IC50 = 38.25 ± 0.12 μM), and also found to be nontoxic. Molecular docking study was carried out in order to establish the structure-activity relationship (SAR) which demonstrated that electron rich centers at one and electron withdrawing centers at the other end of the molecules showed strong inhibitory activity. All the synthesized compounds were characterized by spectroscopic techniques such as EI-MS, HREI-MS, (1)H NMR and (13)C NMR. CHN analysis was also performed.
Current study is based on the biology-oriented drug synthesis (BIODS) of 2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethyl aryl carboxylate derivatives 1-26, by treating metronidazole with different aryl and hetero-aryl carboxylic acids in the presence of 1,1'-carbonyl diimidazole (CDI) as a coupling agent. Structures of all synthetic derivatives were confirmed with the help of various spectroscopic techniques such as EI-MS, (1)H -NMR and (13)C NMR. CHN elemental analyses were also found in agreement with the calculated values. Synthetic derivatives were evaluated to check their β-glucuronidase inhibitory activity which revealed that except few derivatives, all demonstrated good inhibition in the range of IC50 = 1.20 ± 0.01-60.30 ± 1.40 μM as compared to the standard d-saccharic acid 1,4-lactone (IC50 = 48.38 ± 1.05 μM). Compounds 1, 3, 4, 6, 9-19, and 21-24 were found to be potent analogs and showed superior activity than standard. Limited structure-activity relationship is suggested that the molecules having electron withdrawing groups like NO2, F, Cl, and Br, were displayed better activity than the compounds with electron donating groups such as Me, OMe and BuO. To verify these interpretations, in silico study was also performed, a good correlation was observed between bioactivities and docking studies.
Benzothiazole and its natural or synthetic derivatives have been used as precursors for several pharmacological agents for neuroprotective, anti-bacterial, and anti-allergic activities. The objective of the present study was to evaluate effects of benzothiazole analogs (compounds 1-26) for their immunomodulatory activities. Eight compounds (2, 4, 5, 8-10, 12, and 18) showed potent inhibitory activity on PHA-activated peripheral blood mononuclear cells (PBMCs) with IC50 ranging from 3.7 to 11.9 μM compared to that of the standard drug, prednisolone <1.5 μM. Some compounds (2, 4, 8, and 18) were also found to have potent inhibitory activities on the production of IL-2 on PHA/PMA-stimulated PBMCs with IC50 values ranging between <4.0 and 12.8 μM. The binding interaction of these compounds was performed through silico molecular docking. Compounds 2, 8, 9, and 10 significantly suppressed oxidative burst ROS production in phagocytes with IC50 values between <4.0 and 15.2 μM. The lipopolysaccharide (LPS)-induced nitrites in murine macrophages cell line J774 were found to be inhibited by compounds 4, 8, 9, and 18 at a concentration of 25 μg/mL by 56%, 91%, 58%, and 78%, respectively. Furthermore, compounds 5, 8, 12, and 18 showed significant (P<0.05) suppressive activity on Th-2 cytokine, interleukin 4 (IL-4) with an IC50 range of <4.0 to 40.3 μM. Interestingly compound 4 has shown a selective inhibitory activity on IL-2 and T cell proliferation (naïve T cell proliferation stage) rather than on IL-4 cytokine, while compound 12 displayed an interference with T-cell proliferation and IL-4 generation. Moreover compound 8 and 18 exert non-selective inhibition on both IL-2 and IL-4 cytokines, indicating a better interference with stage leading to humoral immune response and hence possible application in autoimmune diseases.
Thiourea derivatives (1-38) were synthesized and evaluated for their urease inhibition potential. The synthetic compounds showed a varying degree of in vitro urease inhibition with IC50 values 5.53 ± 0.02-91.50 ± 0.08 μM, most of which are superior to the standard thiourea (IC₅₀ = 21.00 ± 0.11 μM). In order to ensure the mode of inhibition of these compounds, the kinetic study of the most active compounds has been carried out. Most of these inhibitors were found to be mixed-type of inhibitors, except compounds 13 and 30 which were competitive, while compound 19 was identified as non-competitive inhibitor with Ki values between 8.6 and 19.29 μM.
The synthetic indole Mannich bases 1-13 have been investigated for their ability to modulate immune responses measured in vitro. These activities were based on monitoring their affects on T-lymphocyte proliferation, reactive oxygen species (ROS), IL (interleukin)-2, IL-4, and nitric oxide production. Compound 5 was found to be the most potent immunomodulator in this context. Four of the synthesized compounds, 5, 11, 12, and 13, have significant potent inhibitory effects on T-cell proliferation, IL-4, and nitric oxide production. However, none of the thirteen indole compounds exerted any activity against ROS production.
Aim: To synthesize pyrrolopyridine-based thiazolotriazoles as a novel class of α-amylase and α-glucosidase inhibitors and to determine their enzymatic kinetics. Methodology: Pyrrolopyridine-based thiazolotriazole analogs (1-24) were synthesized and characterized through proton nuclear magnetic resonance, carbon-13 nuclear magnetic resonance and high-resolution electron ionization mass spectrometry. Results: All synthesized analogs displayed good inhibitory potential of α-amylase and α-glucosidase ranging 17.65-70.7 μM and 18.15-71.97 μM, respectively, compared with the reference drug, acarbose (11.98 μM and 12.79 μM). Analog 3 was the most potent among the synthesized analogs, having α-amylase and α-glucosidase inhibitory activity at 17.65 and 18.15 μM, respectively. The structure-activity relationship and binding modes of interactions between selected analogs were confirmed via docking and enzymatic kinetics studies. The compounds (1-24) were tested for cytotoxicity against the 3T3 mouse fibroblast cell line and were observed to be nontoxic.
In an effort to develop new antibacterial drugs, some novel bisindolylmethane derivatives containing Schiff base moieties were prepared and screened for their antibacterial activity. The synthesis of the bisindolylmethane Schiff base derivatives 3-26 was carried out in three steps. First, the nitro group of 3,3'-((4-nitrophenyl)-methylene)bis(1H-indole) (1) was reduced to give the amino substituted bisindolylmethane 2 without affecting the unsaturation of the bisindolylmethane moiety using nickel boride in situ generated. Reduction of compound 1 using various catalysts showed that combination of sodium borohydride and nickel acetate provides the highest yield for compound 2. Bisindolylmethane Schiff base derivatives were synthesized by coupling various benzaldehydes with amino substituted bisindolylmethane 2. All synthesized compounds were characterized by various spectroscopic methods. The bisindolylmethane Schiff base derivatives were evaluated against selected Gram-positive and Gram-negative bacterial strains. Derivatives having halogen and nitro substituent display weak to moderate antibacterial activity against Salmonella typhi, S. paratyphi A and S. paratyphi B.
Naegleria fowleri and Balamuthia mandrillaris are protist pathogens that infect the central nervous system, causing primary amoebic meningoencephalitis and granulomatous amoebic encephalitis with mortality rates of over 95%. Quinazolinones and their derivatives possess a wide spectrum of biological properties, but their antiamoebic effects against brain-eating amoebae have never been tested before. In this study, we synthesized a variety of 34 novel arylquinazolinones derivatives (Q1-Q34) by altering both quinazolinone core and aryl substituents. To study the antiamoebic activity of these synthetic arylquinazolinones, amoebicidal and amoebistatic assays were performed against N. fowleri and B. mandrillaris. Moreover, amoebae-mediated host cells cytotopathogenicity and cytotoxicity assays were performed against human keratinocytes cells in vitro. The results revealed that selected arylquinazolinones derivatives decreased the viability of B. mandrillaris and N. fowleri significantly (P < 0.05) and reduced cytopathogenicity of both parasites. Furthermore, these compounds were also found to be least cytotoxic against HaCat cells. Considering that nanoparticle-based materials possess potent in vitro activity against brain-eating amoebae, we conjugated quinazolinones derivatives with silver nanoparticles and showed that activities of the drugs were enhanced successfully after conjugation. The current study suggests that quinazolinones alone as well as conjugated with silver nanoparticles may serve as potent therapeutics against brain-eating amoebae.
A rare but lethal central nervous system disease known as granulomatous amoebic encephalitis (GAE) and potentially blinding Acanthamoeba keratitis are diseases caused by free-living Acanthamoeba. Currently, no therapeutic agent can completely eradicate or prevent GAE. Synthetic compounds are a likely source of bioactive compounds for developing new drugs. This study synthesized seventeen 1,4-benzothiazine derivatives (I -XVII) by a base-catalyzed one-pot reaction of 2-amino thiophenol with substituted bromo acetophenones. Different spectroscopic techniques, such as EI-MS, 1H-, and 13C NMR (only for the new compounds), were used for the structural characterization and conformation of compounds. These compounds were assessed for the first time against Acanthamoeba castellanii. All compounds showed anti-amoebic potential in vitro against A. castellanii, reducing its ability to encyst and excyst at 100 μM. Compounds IX, X, and XVI showed the most potent activities among all derivatives and significantly reduced the viability to 5.3 × 104 (p
This study reports synthesis of flavone hydrazide Schiff base derivatives with diverse functionalities for the cure of diabetic mellitus and their a-glucosidase inhibitor and in silico studies. In this regard, Flavone derivatives 1-20 has synthesized and characterized by various spectroscopic techniques. These compounds showed significant potential towards a-glucosidase enzyme inhibition activity and found to be many fold better active than the standard Acarbose (IC50 = 39.45 ± 0.11 µM). The IC50values ranges 1.02-38.1 µM. Among these, compounds 1(IC50 = 4.6 ± 0.23 µM), 2(IC50 = 1.02 ± 0.2 µM), 3(IC50 = 7.1 ± 0.11 µM), 4(IC50 = 8.3 ± 0.34 µM), 5(IC50 = 7.4 ± 0.15 µM), 6(IC50 = 8.5 ± 0.27 µM) and 18 (IC50 = 1.09 ± 0.26 µM) showed highest activity. It was revealed that the analogues having -OH substitution have higher activity than their look likes. The molecular docking analysis revealed that these molecules have high potential to interact with the protein molecule and have high ability to bind with the enzyme. Furthermore, in silico pharmacokinetics, physicochemical studies were also performed for these derivatives. The bioavailability radar analysis explored that of all these compounds have excellent bioavailability for five (5) descriptors, however, the sixth descriptor of instauration is slightly increased in all compounds.Communicated by Ramaswamy H. Sarma.
Trillium govanianum is a high-value medicinal herb, having multifunctional traditional and culinary uses. The present investigation was carried out to evaluate the phytochemical, biological and toxicological parameters of the T. govanianum Wall. ex D. Don (Family: Trilliaceae) roots collected from Azad Kashmir, Pakistan. Phytochemical profiling was achieved by determining total bioactive contents (total phenolic and flavonoid contents) and UHPLC-MS analysis. For biological evaluation, antioxidant activities (DPPH, ABTS, FRAP, CUPRAC, phosphomolybdenum, and metal chelation assays) and enzyme inhibition activities (against AChE, BChE, glucosidase, amylase, and tyrosinase) were performed. Moreover, cytotoxicity was assessed against three human carcinoma cell lines (MDA-MB-231, CaSki, and DU-145). The tested extract was found to contain higher total phenolics (7.56 mg GAE/g dry extract) as compared to flavonoid contents (0.45 mg RE/g dry extract). Likewise, for the antioxidant activity, higher CUPRAC activity was noted with 39.84 mg TE/g dry extract values. In the case of enzyme assays, higher activity was pointed out against the cholinesterase, glucosidase and tyrosinase enzymes. The plant extract displayed significant cytotoxicity against the cell lines examined. Moreover, the in-silico studies highlighted the interaction between the important phytochemicals and tested enzymes. To conclude, the assessed biological activity and the existence of bioactive phytochemicals in the studied plant extract may pave the way for the development of novel pharmaceuticals.
Benzothiazole analogs (1-20) have been synthesized, characterized by EI-MS and (1)H NMR, and evaluated for urease inhibition activity. All compounds showed excellent urease inhibitory potential varying from 1.4±0.10 to 34.43±2.10μM when compared with standard thiourea (IC50 19.46±1.20μM). Among the series seventeen (17) analogs 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, and 18 showed outstanding urease inhibitory potential. Analogs 15 and 19 also showed good urease inhibition activity. When we compare the activity of N-phenylthiourea 20 with all substituted phenyl derivatives (1-18) we found that compound 15 showed less activity than compound 20 having 3-methoxy substituent. The binding interactions of these active analogs were confirmed through molecular docking.
Thiadiazole derivatives 1-24 were synthesized via a single step reaction and screened for in vitro β-glucuronidase inhibitory activity. All the synthetic compounds displayed good inhibitory activity in the range of IC50=2.16±0.01-58.06±1.60μM as compare to standard d-saccharic acid 1,4-lactone (IC50=48.4±1.25μM). Molecular docking study was conducted in order to establish the structure-activity relationship (SAR) which demonstrated that thiadiazole as well as both aryl moieties (aryl and N-aryl) involved to exhibit the inhibitory potential. All the synthetic compounds were characterized by spectroscopic techniques (1)H, (13)C NMR, and EIMS.
The present study describes several novel 2,5-biaryl-3-hexylthiophene derivatives (3a-i) synthesized via a Pd(0)-catalyzed Suzuki cross-coupling reaction in moderate to good yields. The novel compounds were also analyzed for their anti-thrombolytic, haemolytic, and biofilm inhibition activities. In addition, the anti-tumor activity was also evaluated in vitro for newly-synthesized compounds, where 3-hexyl-2,5-bis(4-(methylthio)phenyl)thiophene exhibited the best anti-tumor activity against 4T1 cells with IC50 value of 16 μM. Moreover, 2,5-bis(4-methylphenyl)-3-hexylthiophene showed the highest activity against MCF-7 cells with an IC50 value of 26.2 μM. On the other hand, the compound 2,5-bis(4-chloropheny)-3-hexylthiophene exhibited excellent biofilm inhibition activity. Furthermore, the compound 2,5-bis(3-chloro-4-fluorophenyl)-3-hexylthiophene also exhibited better anti-thrombolytic and hemolytic activity results as compared to the other newly-synthesized compounds.
A variety of dihydroquinazolin-4(1H)-one derivatives (1-37) were synthesized via "one-pot" three-component reaction scheme by treating aniline and different aromatic aldehydes with isatoic anhydride in the presence of acetic acid. Chemical structures of compounds were deduced by different spectroscopic techniques including EI-MS, HREI-MS, 1H-, and 13C-NMR. Compounds were subjected to α-amylase and α-glucosidase inhibitory activities. A number of derivatives exhibited significant to moderate inhibition potential against α-amylase (IC50 = 23.33 ± 0.02-88.65 ± 0.23 μM) and α-glucosidase (IC50 = 25.01 ± 0.12-89.99 ± 0.09 μM) enzymes, respectively. Results were compared with the standard acarbose (IC50 = 17.08 ± 0.07 μM for α-amylase and IC50 = 17.67 ± 0.09 μM for α-glucosidase). Structure-activity relationship (SAR) was rationalized by analyzing the substituents effects on inhibitory potential. Kinetic studies were implemented to find the mode of inhibition by compounds which revealed competitive inhibition for α-amylase and non-competitive inhibition for α-glucosidase. However, in silico study identified several important binding interactions of ligands (synthetic analogues) with the active site of both enzymes.
Over-expression of α-amylase enzyme causes hyperglycemia which lead to many physiological complications including oxidative stress, one of the most commonly associated problem with diabetes mellitus. Marketed α-amylase inhibitors such as acarbose, voglibose, and miglitol used to treat type-II diabetes mellitus, but also linked to several harmful effects. Therefore, it is essential to explore new and nontoxic antidiabetic agents with additional antioxidant properties. In this connection, a series of new N-sulfonohydrazide substituted indazoles 1-19 were synthesized by multistep reaction scheme and assessed for in vitro α-amylase inhibitory and radical (DPPH and ABTS) scavenging properties. All compounds were fully characterized by different spectroscopic techniques including 1H, 13C NMR, EI-MS, HREI-MS, ESI-MS, and HRESI-MS. Compounds showed promising α-amylase inhibitory activities (IC50 = 1.23 ± 0.06-4.5 ± 0.03 µM) as compared to the standard acarbose (IC50 1.20 ± 0.09 µM). In addition to that all derivatives were found good to moderate scavengers of DPPH (IC50 2.01 ± 0.13-5.3 ± 0.11) and ABTS (IC50 = 2.34 ± 0.07-5.5 ± 0.07 µM) radicals, in comparison with standard ascorbic acid having scavenging activities with IC50 = 1.99 ± 0.09 µM, and IC50 2.03 ± 0.11 µM for DPPH and ABTS radicals. In silico molecular docking study was conducted to rationalize the binding interaction of α-amylase enzyme with ligands. Compounds were observed as mixed type inhibitors in enzyme kinetic characterization.