Potential of Tryptamine Derivatives as Multi-Target Directed Ligands for Alzheimer's Disease: AChE, MAO-B, and COX-2 as Molecular Targets.

Extensive research has been dedicated to develop compounds that can target multiple aspects of Alzheimer's disease (AD) treatment due to a growing understanding of AD's complex multifaceted nature and various interconnected pathological pathways. In the present study, a series of biological assays were performed to evaluate the potential of the tryptamine analogues synthesized earlier in our lab as multi-target-directed ligands (MTDLs) for AD. To assess the inhibitory effects of the compounds, various in vitro assays were employed. Three compounds, SR42, SR25, and SR10, displayed significant AChE inhibitory activity, with IC50 values of 0.70 µM, 0.17 µM, and 1.00 µM, respectively. These values superseded the standard drug donepezil (1.96 µM). In the MAO-B inhibition assay, SR42 (IC50 = 43.21 µM) demonstrated superior inhibitory effects as compared to tryptamine and other derivatives. Moreover, SR22 (84.08%), SR24 (79.30%), and SR42 (75.16%) exhibited notable percent inhibition against the COX-2 enzyme at a tested concentration of 100 µM. To gain insights into their binding mode and to validate the biological results, molecular docking studies were conducted. Overall, the results suggest that SR42, a 4,5 nitro-benzoyl derivative of tryptamine, exhibited significant potential as a MTDL and warrants further investigation for the development of anti-Alzheimer agents.

Revealing analgesic and anxiolytic potentials of synthetic benzimidazole analogues: An in-vivo and in-silico study.

Certain drugs have potential to affect and alter individual's behavior. On the other hand, pain is a complex phenomenon with various treatment options; analgesic medicines are the primary source. Therefore, this study was based on examining some of the benzimidazole analogues for their analgesic as well as behavioral potential following Tail immersion test and Open field test respectively. In addition, molecular docking was performed to find the interaction of these compounds with the active site using AutoDock Vina which was further visualized through Discovery Studio Visualizer. It was seen that the cyano-methyl benzimidazole derivatives (CMB1-CMB3) showed relief in pain as compared to benzimidazole derivatives (BI1-BI3), CMB2 demonstrated highly potent analgesic effect. Likewise, all structures except BI1 displayed increase locomotion during open field test and can be offered as anxiolytic compounds. Almost all derivatives showed improve binding energies for the tested proteins where the high analgesic action of CMB2 might be correlated to its high binding affinity and interaction at µOR. It was also noticed that all structures except BI showed possible binding interaction with GABAA receptor and hence possessed anxiolytic like potential. Thus, this study offered benzimidazole analogues for further drug development of analgesic and anxiolytic like compounds.

Determination of ionization constant and drug-likeness prediction of synthetic isoniazid derivatives.

Determination of ionization constant, commonly termed pKa is of prime interest in a wide range of pharmaceutical Research fields. The pKa of a compound is critical as it influences on its physicochemical parameters in biological and environmental systems. The study of pKa is also essential not only for the formulation of drugs and optimization of a variety of novel analytical methods, establishing new pharmaceutical dosage forms yet the exploration of the mechanism of action of drugs. In this research work, we have determined pKa values of isoniazid (INH) derivatives; N'-[(4-methyl benzoyl)] pyridine-4-carbohydrazide (I) and [2-oxo-2-(4-phenyl phenyl) ethyl] (pyridine-4-yl formamido) azanium bromide (II) through UV- spectrophotometry, a method is known for the accuracy and precision of results. These two compounds (I and II) were synthetically prepared in our lab by derivatizing INH and reported by Naeem et al in the year 2014. The mean pKa values for compounds I and II were experimentally determined as 7.37 and 3.76 respectively. The study is helpful in understanding the physicochemical behavior of these compounds in a biological system. Different pharmacokinetic parameters were also predicted using online web tools which ensured significant drug-likeness for both compounds.

New series of hydrazinyl thiazole derivatives of piperidin-4-one: Synthesis, structural elucidation, analgesic activity and comparative structure activity relationship.

Seven new hydrazinyl thiazole derivatives of piperidin-4-one (PE3-PE9) have been synthesized by cyclization of intermediate thiosemicarbazone derivative (PE2). Parent molecule (PE1) was synthesized by one pot total synthesis using Mannich condensation reaction. Percent yield of most of the compounds found in between 70-85%. Compounds were identified by spectroscopic analysis. In vivo analgesic activity was examined using tail flick method. One-way ANOVA was used to compare the mean latency time of synthesized derivatives with control and standard. Analgesic activity was discussed in terms of structural differences between compounds. Among allthe derivatives thiosemicarbazone derivative showed good analgesic activity (195.24%). Methoxy (-OCH3) and bromo (-Br) containing thiazole derivative also showed good pain reducing property (167.62%, 203%) at a dose of 30mg/kg.

1,3-di-4-piperidylpropane derivatives as potential acetyl cholinesterase antagonists: Molecular docking, synthesis, and biological evaluation.

Acetylcholine esterase (AChE) is a key biological target responsible for the management of cholinergic transmission, and its inhibitors are used for the therapy of Alzheimer's disease. In the present study, a small library of molecules with 1,3-di-4-piperidylpropane nucleus were docked on AChE. The selected compounds were synthesized and evaluated for their enzyme inhibition. P25 and P17 expressed significantly higher AChE inhibition than standards with IC50 values of 0.591µM and 0.625µM, respectively. Binding mode of derivatives in the active site of AChE revealed dual binding of molecules in peripheral anionic site (PAS) and catalytic anionic site (CAS) of enzyme cavity.

In-silico determination of pKa and logp values of some isoniazid synthetic analogues using Marvin software.

Among the physicochemical properties, pKa and LogP values help us in studying drug parameters like ADME and could be predicted to some extent. With this view, here we wish to predict these two properties of our previously synthesized biologically active derivatives of isoniazid using on-line available program Marvin, a Java-based chemical software application frequently used for chemical modeling. According to Marvin, pKa values predicted 99.99% unionized states of INH and some derivatives at physiological pH 7.4. Marvin calculated LogP values estimated good oral absorption for all the synthesized compounds. Therefore it can be said that the findings of the study emerged in an ideal region that permits the formulation of these derivatives. Since this was just a theoretical study, it demands more experimentation to determine accurate situation.

Molecular docking, synthesis and biological evaluation of phenacyl derivatives of 9-aminoacridine as anti-Alzheimer's agent.

Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder mainly characterized by progressive deterioration of memory and impaired cognitive function. The most promising approach for symptomatic relief of AD is to inhibit acetylcholinesterase (AChE). On the basis of this approach in-house library of 9-aminoacridine derivatives were constructed and allowed to docked against human acetylcholinesterase (hAChE) (PDB ID: 4EY7), using MOE 2018.01 and PyRx 0.9.2 (AutoDock Vina). Top ranked and best fitted molecules were synthesized by targeting the 9-amino group of aminoacridine with substituted phenacyl halides. Anti-Alzheimer's potential was checked by in vitro AChE inhibition, antioxidant activity (DPPH scavenging ability) and fibril disaggregation. Subjected ligands suggested as promising multitargeted candidate with pronounced results in term of IC50 values (AChE inhibition 2.400-26.138µM), however, none of them showed potential towards fibril inhibition.

MeCP2_E1 N-terminal modifications affect its degradation rate and are disrupted by the Ala2Val Rett mutation.

Methyl CpG-binding protein 2 (MeCP2), the mutated protein in Rett syndrome (RTT), is a crucial chromatin-modifying and gene-regulatory protein that has two main isoforms (MeCP2_E1 and MeCP2_ E2) due to the alternative splicing and switching between translation start codons in exons one and two. Functionally, these two isoforms appear to be virtually identical; however, evidence suggests that only MeCP2_E1 is relevant to RTT, including a single RTT missense mutation in exon 1, Ala2Val. Here, we show that N-terminal co- and post-translational modifications differ for MeCP2_E1 and MeCP2_E1-Ala2Val, which result in different protein degradation rates in vitro. We report complete N-methionine excision (NME) for MeCP2_E1 and evidence of excision of multiple alanine residues from the N-terminal polyalanine stretch. For MeCP2_E1-Ala2Val, we observed only partial NME and N-acetylation (NA) of either methionine or valine. The localization of MeCP2_E1 and co-localization with chromatin appear to be unaffected by the Ala2Val mutation. However, a higher proteasomal degradation rate was observed for MeCP2_E1-Ala2Val compared with that for wild type MeCP2_E1. Thus, the etiopathology of Ala2Val is likely due to a reduced bio-availability of MeCP2 because of the faster degradation rate of the unmodified defective protein. Our data on the effects of the Ala2Val mutation on N-terminal modifications of MeCP2 may be applicable to Ala2Val mutations in other disease genes for which no etiopathological mechanism has been established.

Pharmacophoric screening of newly synthesized isoniazid derivatives and their antimycobacterial activity.

Mycobacterium tuberculosis is clinically recognized as a causative agent of Tuberculosis. Keeping in view, this study was endeavored to screen our previously synthesized seventeen INH analogues for their antimycobacterial potential using proportion method. During this process, INH and all the seventeen compounds were examined at different concentrations of 0.05, 0.1 and 0.2µg/mL which were prepared using Lowenstein-Jensen (LJ) base. For drug susceptibility test, three Mycobacterial strains ATCC H37Rv, known INH-sensitive and INH-resistant strains were selected, sub-cultured on LJ Medium and serial diluted to achieve 1:10, 1:100, 1:1000 and 1:10000 from calibrated bacterial suspension Mcfarland No. 1. Dilutions of 1:100 and 1:10000 were added to drug free medium and 1:100 bacterial suspension was added to each of the test concentrations and finally incubated for 4-6 weeks at 37°C. It was observed that only compounds II and XI were active against MTb. Compounds III, IX and X also showed activity but were less potent. Ligand Scout 3.02[il_10] was used to perform pharmacophore-based screening where important pharmacophoric features were identified in the structures of these compounds which could be related to their observed antimycobacterial activity.

Synthesis, characterization and SAR of novel Bezimidazole derivatives as Nematicidal agents.

Six novel analogues were prepared by reacting benzimidazole molecules (BM and CMB) propiophenone and benzoyl chlorides respectively. The structures of newly synthesized compounds were determined with the help of spectroscopic techniques. The compounds were subjected to in-vitro screening for their activity against nematodes. It was observed that the benzimidazole (BM) derivatives possessed more nematicidal activity as compared to that of cyanomethyl-benzimidazole (CMB) for Meloidogyne incognita. Among them, the propiophenone substituted benzimidazole derivative B3 was found to be the most active compound and can be further studied as lead molecule for development of anthelmintic drugs.

Cytotoxic and acute toxicity studies of isoniazid derivatives.

Cancer is ultimately the result of cells that hysterically grow and do not die. Cells can experience uncontrolled growth if there are mutations to DNA, and therefore, alterations to the genes involved in cell division. Cancer occurs when a cell's gene mutations make the cell unable to correct DNA damage and is unable to destroy itself. There are over 100 different types of cancer each classified by the type of initially affected cell. Isoniazid, a well-known antitubercular agent has been reported to exhibit some cytotoxic activity. This finding prompt us to carry out this study where isoniazid and its sixteen derivatives were studied for any possible cytotoxic activity against Human astrocytoma SNB-19 cells, human Dukes' type C colorectal adenocarcinoma HCT-15 cells, human Dukes' type D colorectal adenocarcinoma COLO-205 cells, and human prostate adenocarcinoma (grade IV) PC-3 cells. Among the test compounds, SN-07 (a phenacyl derivative with para phenyl substitution) demonstrated slight cytotoxic effects on two types of human colorectal adenocarcinoma cells HCT-15 and COLO-205. Moreover, the acute toxicity of the compounds was also estimated in which some compounds were evaluated with more LD50 values than isoniazid.

Analgesic activity of alkyl piperidine derivatives.

Piperidine is the most significant scaffold which reveals therapeutic potential because of its conformationally flexible nature. During the course of present investigations synthetic quaternary salts of alkyl piperidine with various phenacyl bromides were explored for their possible analgesic activity. Compounds I analogs (1a-1f) and compound II analogs (IIa-IIf) showed varying degree of analgesic activity when compared with pethidine as standard and its duration by tail immersion method.

Antimicrobial and antioxidant screening of N¢-substituted sulphonyl and benzoyl derivatives of 4-Pyridine carboxylic acid hydrazide.

In this research program, the antibacterial, antifungal and antioxidant activities of six N'-substituted sulfonyl and benzoyl derivatives of lead molecule PCH were reported. Out of these compounds, sulphonyl derivatives 2,3 and benzoyl derivative 5 showed moderate to good activity against different strains of gram-positive and gram-negative bacteria including B. cereus, B. subtilis, B. thruingiensis and S. pyogenes, S. fecalis and E. coli ATCC 8739. Moreover, upon antifungal screening, the compound, N¢-[(2,4,6-trimethylbenzene) sulfonyl]pyridine-4-carbohydrazide possessed good antifungal activity against Candida species, a causative agent of systemic fungal infections. Antioxidant study demonstrated more than 50% inhibition in DPPH assay for sulphonyl derivative 2 indicating its potential as antioxidant while the other derivatives expressed low level of radical scavenging property.

Physicochemical characteristics, functional properties, and nutritional benefits of peanut oil: a review.

The legume Arachis hypogaea, commonly known as peanut or groundnut, is a very important food crop throughout the tropics and subtropics. Peanut is one of the most widely used legumes due to its nutrition and taste, and it occupies a rank of major oilseed crop in the world. It has been recognized as a functional food due to its role in a health promoting effect. Peanut oil contains a well-balanced fatty acid and antioxidant profile that provide protection against harmful substances especially free radicals. This paper gives an overview of scientific literature available on phytochemical and functional properties of peanut oil. Owing to its unique organoleptic properties associated with its cardioprotective and anti-inflammatory properties, peanut oil has found, recently, its place on the highly competitive international edible oil market.

Chitosan and chitosan-co-poly(epsilon-caprolactone) grafted multiwalled carbon nanotube transducers for vapor sensing.

Vapor sensitive transducer films consisting of chitosan grafted (CNT-CS) and chitosan-co-polycaprolactone grafted (CNT-CS-PCL) multiwalled carbon nanotubes were prepared using a spray layer-by-layer technique. The synthesized materials (CNT-CS and CNT-CS-PCL) were characterized by Fourier transform infrared spectroscopy, 13C CP/MAS solid state nuclear magnetic resonance spectroscopy and thermogravimetric analysis. Both CNT-CS and CNT-CS-PCL transducers were analyzed for the response of volatile organic compounds and toluene vapors. The ranking of the relative resistance (A(r)) for both chitosan based transducers were as follows: toluene < chloroform < ethanol < methanol. The CNT transducer (CNT-CS) was correlated selectively with an exponential law to the inverse of Flory-Huggins interaction parameters, chi12. Dosing the films on the interdigitated electrodes with methanol, ethanol, chloroform and toluene vapors increased the film resistance of CNT-CS but decreased the resistance of CNT-CS-PCL compared to that of the reported transducers.

Synthesis of novel derivatives of 4-pyridine carboxylic acid hydrazide and their activity on central nervous system.

Six novel derivatives (2-7) of 4-Pyridine carboxylic acid hydrazide (PCH) were synthesized by treating this lead molecule with substituted arylsulphonyl and benzoyl chlorides. The molecular structures of the newly derived products were characterized by the help of UV Visible, IR, FAB, 1HNMR spectroscopy and CHN analysis. During the preliminary pharmacological screening, it was observed that the synthesized compounds induced noticeable changes on motor activity of the animals. Interesting structure activity relationship was also observed among the synthesized molecules. Because of the interesting affect on motor activity, the newly synthesized derivatives can further be evaluated for their effects on CNS.

Determination of pKa values of new phenacyl-piperidine derivatives by potentiometric titration method in aqueous medium at room temperature (25±0.5oC).

Dissociation constant (pKa) of ten novel phenacyl derivatives of piperidine were determined by potentiometric titration method in aqueous medium at room temperature (25 ±0.5°C). The sample solutions were prepared in deionized water with ionic strength 0.01M and titrated with 0.1M NaOH solution. In addition, ΔG values were also calculated. Different prediction software programs were used to calculate pKa values too and compared to the experimentally observed pKa values. The experimental and theoretical values were found in close agreement. The results obtained in this research would help to predict the good absorption of the studied compounds and can be selected as lead molecules for the synthesis of CNS active agents because of their lipophilic nature especially compound VII.

Nitrite reductase NirBD is induced and plays an important role during in vitro dormancy of Mycobacterium tuberculosis.

Mycobacterium tuberculosis is one of the strongest reducers of nitrate among all mycobacteria. Reduction of nitrate to nitrite, mediated by nitrate reductase (NarGHJI) of M. tuberculosis, is induced during the dormant stage, and the enzyme has a respiratory function in the absence of oxygen. Nitrite reductase (NirBD) is also functional during aerobic growth when nitrite is the sole nitrogen source. However, the role of NirBD-mediated nitrite reduction during the dormancy is not yet characterized. Here, we analyzed nitrite reduction during aerobic growth as well as in a hypoxic dormancy model of M. tuberculosis in vitro. When nitrite was used as the sole nitrogen source in the medium, the organism grew and the reduction of nitrite was evident in both hypoxic and aerobic cultures of M. tuberculosis. Remarkably, the hypoxic culture of M. tuberculosis, compared to the aerobic culture, showed 32- and 4-fold-increased expression of nitrite reductase (NirBD) at the transcription and protein levels, respectively. More importantly, a nirBD mutant of M. tuberculosis was unable to reduce nitrite and compared to the wild-type (WT) strain had a >2-log reduction in viability after 240 h in the Wayne model of hypoxic dormancy. Dependence of M. tuberculosis on nitrite reductase (NirBD) was also seen in a human macrophage-based dormancy model where the nirBD mutant was impaired for survival compared to the WT strain. Overall, the increased expression and essentiality of nitrite reductase in the in vitro dormancy models suggested that NirBD-mediated nitrite reduction could be critical during the persistent stage of M. tuberculosis.

Development of insecticide resistance in field populations of Brevicoryne brassicae (Hemiptera: Aphididae) in Pakistan.

Cabbage aphid Brevicoryne brassicae (L.) (Hemiptera: Aphididae) is a serious pest of crucifers in Pakistan. After incidences of poor control by recommended insecticides, the current study was undertaken to find out the status of insecticide resistance in Pakistani B. brassicae. Apterous adult aphids were bioassayed from 2006 to 2010 for their response to 12 insecticides using an adult immersion method. No or very low levels of resistance was found to endosulfan; and the organophosphates: chlorpyrifos and profenofos. Resistance to methomyl; emamectin benzoate; the pyrethroids: cypermethrin, lambdacyhalothrin, bifenthrin and deltamethrin; and the neonicotinoids: imidacloprid, acetamiprid, and thiamethoxam; increased progressively in concurrence with their regular use on vegetables. B. brassicae resistance to these insecticides remained very low to low in 2007 and 2008, but then it increased to moderate to high levels in 2009 (except cypermethrin and bifenthrin) and 2010. Under heavy infestations of this aphid, the application of insecticides having no, very low and low resistance is recommended in rotation.

Synthesis and cytotoxic activity of some derivatives of alkyl piperidine.

Synthesis of novel phenacyl derivatives of alkyl piperidine as cytotoxic agents via simple and single step reaction procedure is going to be reported here. Twelve new compounds were successfully synthesized in moderate yield and in solid form. Their synthesis was confirmed by TLC, melting point, CHN analysis and through different spectral studies such as UV, IR, Mass and proton NMR. The advantages of this synthetic route are simple operation, mild reaction conditions and good yields. These newly synthesized derivatives were extensively explored for their cytotoxicity by brine shrimp lethality assay.