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Synthesis of indole-substituted thiosemicarbazones as an aldose reductase inhibitor: an in vitro, selectivity and in silico study

Shehzad MT, Khan A, Halim SA, Hameed A, Imran A, Iqbal J, et al.

Future Med Chem, 2021 07;13(14):1185-1201.
PMID: 34148377 DOI: 10.4155/fmc-2020-0060

Aim: Indole is an important component of many drug molecules, and its conjugation with thiosemicarbazone moiety would be advantageous in finding lead compounds for the development of diabetic complications. Methodology: We have designed, synthesized and evaluated a series of 17 indole-thiosemicarbazones (3a-q) as aldose reductase (ALR2) and aldehyde reductase (ALR1) inhibitors. Results: After in vitro evaluation, all indole-thiosemicarbazones showed significant inhibition against both enzyme ALR1 and ALR2 with IC50 in range of 0.42-20.7 and 1.02-19.1 μM, respectively. The docking study was also carried out to consider the putative binding of molecules with the target enzymes. Conclusion: Compound 3f was found to be most active and selective for ALR2. The indole-thiosemicarbazones series described here has selective hits for diabetes-mellitus-associated complications.
Sulfonylhydrazones: Design, synthesis and investigation of ectonucleotidase (ALP & e5'NT) inhibition activities

Younus HA, Hameed A, Mahmood A, Khan MS, Saeed M, Batool F, et al.

Bioorg Chem, 2020 07;100:103827.
PMID: 32402802 DOI: 10.1016/j.bioorg.2020.103827

Medicinal importance of the sulfonylhydrazones is well-evident owing to their binding ability with zinc containing metalloenzymes. In the present study, we have synthesized different series of sulfonylhydrazones by using facile synthetic methods in good to excellent yield. All the successfully prepared sulfonylhydrazones were screened for ectonucleotidase (ALP & e5'NT) inhibitory activity. Among the chromen-2-one scaffold based sulfonylhydrazones, the compounds 7 was found to be most potent inhibitor for h-TNAP (human tissue non-specific alkaline phosphatase) and h-IAP (human intestinal alkaline phosphatase) with IC50 values of 1.02 ± 0.13 and 0.32 ± 0.0 3 µM respectively, compared with levamisole (IC50 = 25.2 ± 1.90 µM for h-TNAP) and l-phenylalanine (IC50 = 100 ± 3.00 µM for h-IAP) as standards. Further, the chromen-2-one based molecule 5a showed excellent activity against h-ecto 5'-NT (human ecto-5'-nucleotidase) with IC50 value of 0.29 ± 0.004 µM compared to standard, sulfamic acid (IC50 = 42.1 ± 7.8 µM). However, among the series of phenyl ring based sulfonylhydrazones, compound 9d was found to be most potent against h-TNAP and h-IAP with IC50 values of 0.85 ± 0.08 and 0.52 ± 0.03 µM, respectively. Moreover, in silico studies were also carried to demonstrate their putative binding with the target enzymes. The potent compounds 5a, 7, and 9d against different ectonucleotidases (h-ecto 5'-NT, h-TNAP, h-IAP) could potentially serve as lead for the development of new therapeutic agents.
Deep eutectic solvent mediated synthesis of 3,4-dihydropyrimidin-2(1H)-ones and evaluation of biological activities targeting neurodegenerative disorders

Saleem Khan M, Asif Nawaz M, Jalil S, Rashid F, Hameed A, Asari A, et al.

Bioorg Chem, 2022 01;118:105457.
PMID: 34798458 DOI: 10.1016/j.bioorg.2021.105457

Substitution of hazardous and often harmful organic solvents with "green" and "sustainable" alternative reaction media is always desirous. Ionic liquids (IL) have emerged as valuable and versatile liquids that can replace most organic solvents in a variety of syntheses. However, recently new types of low melting mixtures termed as Deep Eutectic Solvents (DES) have been utilized in organic syntheses. DES are non-volatile in nature, have sufficient thermal stability, and also have the ability to be recycled and reused. Hence DES have been used as alternative reaction media to perform different organic reactions. The availability of green, inexpensive and easy to handle alternative solvents for organic synthesis is still scarce, hence our interest in DES mediated syntheses. Herein we have investigated Biginelli reaction in different DES for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones. Monoamine oxidases and cholinesterases are important drug targets for the treatment of various neurological disorders such as Alzheimer's disease, Parkinson's disease, depression and anxiety. The compounds synthesized herein were evaluated for their inhibitory potential against these enzymes. Some of the compounds were found to be highly potent and selective inhibitors. Compounds 1 h and 1c were the most active monoamine oxidase A (MAO A) (IC50 = 0.31 ± 0.11 µM) and monoamine oxidase B (MAO B) (IC50 = 0.34 ± 0.04 µM) inhibitors respectively. All compounds were selective AChE inhibitors and did not inhibit BChE (<29% inhibition). Compound 1 k (IC50 = 0.13 ± 0.09 µM) was the most active AChE inhibitor.
Exploring chromone sulfonamides and sulfonylhydrazones as highly selective ectonucleotidase inhibitors: Synthesis, biological evaluation and in silico study

Younus HA, Saeed M, Mahmood A, Jadoon MSK, Hameed A, Asari A, et al.

Bioorg Chem, 2023 May;134:106450.
PMID: 36924652 DOI: 10.1016/j.bioorg.2023.106450

Ectonucleotidases, a well-known superfamily of plasma membrane located metalloenzymes plays a central role in mediating the process of purinergic cell signaling. Major functions performed by these enzymes include the hydrolysis of extracellular nucleosides and nucleotides which are considered as important cell-signaling molecules. Any (patho)-physiologically induced disruption in this purinergic cell signaling leads to several disorders, hence these enzymes are important drug targets for therapeutic purposes. Among the major challenges faced in the design of inhibitors of ectonucleotidases, an important one is the lack of selective inhibitors. Access to highly selective inhibitors via a facile synthetic route will not only be beneficial therapeutically, but will also lead to an increase in our understanding of intricate interplay between members of ectonucleotidase enzymes in relation to their selective activation and/or inhibition in different cells and tissues. Herein we describe synthesis of highly selective inhibitors of human intestinal alkaline phosphatase (h-IAP) and human tissue non-specific alkaline phosphatase (h-TNAP), containing chromone sulfonamide and sulfonylhydrazone scaffolds. Compound 1c exhibited highest (and most selective) h-IAP inhibition activity (h-IAP IC50 = 0.51 ± 0.20 µM; h-TNAP = 36.5%) and compound 3k showed highest activity and selective inhibition against h-TNAP (h-TNAP IC50 = 1.41 ± 0.10 µM; h-IAP = 43.1%). These compounds were also evaluated against another member of ectonucleotidase family, that is rat and human ecto-5'-nucleotidase (r-e5'NT and h-e5'NT). Some of the compounds exhibited excellent inhibitory activity against ecto-5'-nucleotidase. Compound 2 g exhibited highest inhibition against h-e5'NT (IC50 = 0.18 ± 0.02 µM). To rationalize the interactions with the binding site, molecular docking studies were carried out.
Fulltext Mechanical and Thermal Properties of Montmorillonite-Reinforced Polypropylene/Rice Husk Hybrid Nanocomposites

Majeed K, Ahmed A, Abu Bakar MS, Indra Mahlia TM, Saba N, Hassan A, et al.

Polymers (Basel), 2019 Sep 25;11(10).
PMID: 31557811 DOI: 10.3390/polym11101557

In recent years, there has been considerable interest in the use of natural fibers as potential reinforcing fillers in polymer composites despite their hydrophilicity, which limits their widespread commercial application. The present study explored the fabrication of nanocomposites by melt mixing, using an internal mixer followed by a compression molding technique, and incorporating rice husk (RH) as a renewable natural filler, montmorillonite (MMT) nanoclay as water-resistant reinforcing nanoparticles, and polypropylene-grafted maleic anhydride (PP-g-MAH) as a compatibilizing agent. To correlate the effect of MMT delamination and MMT/RH dispersion in the composites, the mechanical and thermal properties of the composites were studied. XRD analysis revealed delamination of MMT platelets due to an increase in their interlayer spacing, and SEM micrographs indicated improved dispersion of the filler(s) from the use of compatibilizers. The mechanical properties were improved by the incorporation of MMT into the PP/RH system and the reinforcing effect was remarkable as a result of the use of compatibilizing agent. Prolonged water exposure of the prepared samples decreased their tensile and flexural properties. Interestingly, the maximum decrease was observed for PP/RH composites and the minimum was for MMT-reinforced and PP-g-MAH-compatibilized PP/RH composites. DSC results revealed an increase in crystallinity with the addition of filler(s), while the melting and crystallization temperatures remained unaltered. TGA revealed that MMT addition and its delamination in the composite systems improved the thermal stability of the developed nanocomposites. Overall, we conclude that MMT nanoclay is an effective water-resistant reinforcing nanoparticle that enhances the durability, mechanical properties, and thermal stability of composites.
Fulltext Physio-chemical characterization of indigenous agricultural waste materials for the development of potting media

Kiran S, Iqbal J, Danish S, Bakhsh A, Bukhari SIUS, Bibi F, et al.

Saudi J Biol Sci, 2021 Dec;28(12):7491-7498.
PMID: 34867054 DOI: 10.1016/j.sjbs.2021.08.058

Organic residues are an important factor that directly affects fruiting tree seedlings' health at earlier stages. It provides a suitable environment for seedling growth by providing better nutrient ions, water, and aeration. However, low organic contents and high shrinkage of most organic materials mostly deteriorate ideal potting media characteristics. Low aeration, high water, and nutrients leaching decrease seedling growth and cause a significant loss of valuable resources. That is why the current study was conducted to screen out the best indigenous materials based on particle size to produce good characteristics bearing potting media. For that, eight different ingredients, i.e., "sugarcane", "coconut coir", "wheat straw", "rice straw", "corn cob", "leaf litter", "farmyard manure", and "sunflower heads" were collected. Initially, all the materials were air-dried and processes as per requirement. After grinding, three particles size (fine = < 2 mm, medium = 3 mm and coarse = 5 mm) were separated by sieving. Results showed that decreasing particle size in "rice straw", "corn cob", "farmyard manure," and "sunflower head" decreased leachate pH. Higher EC in leachates was negatively correlated with particle size in all potting media ingredients. Except for farmyard manure, fine particle size increases the water-holding ability of potting media ingredients. However, air-filled porosity was associated with a decrease in particle size of potting media in gradients. In conclusion, farmyard manure, "sunflower heads", "leaf litter" and "sugarcane" should be incorporated while making a combination for potting media. More investigations are suggested by mixing different particle size ingredients to prepare potting media.
Ten-year survival in women with primary stage IV breast cancer

Eng LG, Dawood S, Sopik V, Haaland B, Tan PS, Bhoo-Pathy N, et al.

Breast Cancer Res Treat, 2016 11;160(1):145-152.
PMID: 27628191

PURPOSE: To evaluate breast cancer-specific survival at 10 years in patients who present with primary stage IV breast cancer, and to determine whether survival varies with age of diagnosis.
METHODS: We retrieved the records of 25,323 women diagnosed with primary stage IV breast cancer in the surveillance, epidemiology, and end results 18 registries database from 1990 to 2012. For each case, we extracted information on age at diagnosis, tumour size, nodal status, oestrogen receptor status, progesterone receptor status, ethnicity, cause of death and date of death. The Cox proportional hazards model was used to estimate the unadjusted and adjusted hazard ratio (HR) of death due to stage IV breast cancer, according to age group.
RESULTS: Among 25,323 women with stage IV breast cancer, 2542 (10.0 %) were diagnosed at age 40 or below, 5562 (22.0 %) were diagnosed between ages 41 and 50 and 17,219 (68.0 %) were diagnosed between ages 51 and 70. After a mean follow-up of 2.2 years, 16,387 (64.7 %) women died of breast cancer (median survival 2.3 years). The ten-year actuarial breast cancer-specific survival rate was 15.7 % for women ages 40 and below, 14.9 % for women ages 41-50 and 11.7 % for women ages 51 to 70 (p
Fulltext A Novel Design and Development of a Strip-Fed Circularly Polarized Rectangular Dielectric Resonator Antenna for 5G NR Sub-6 GHz Band Applications

Illahi U, Iqbal J, Irfan M, Ismail Sulaiman M, Khan MA, Rauf A, et al.

Sensors (Basel), 2022 Jul 25;22(15).
PMID: 35898037 DOI: 10.3390/s22155531

In this article, a rectangular dielectric resonator antenna (RDRA) with circularly polarized (CP) response is presented for 5G NR (New Radio) Sub-6 GHz band applications. A uniquely shaped conformal metal feeding strip is proposed to excite the RDRA in higher-order mode for high gain utilization. By using the proposed feeding mechanism, the degenerate mode pair of the first higher-order, i.e., TEδ13x at 4.13 GHz and TE1δ3y, at 4.52 GHz is excited to achieve a circularly polarized response. A circular polarization over a bandwidth of ~10%, in conjunction with a wide impedance matching over a bandwidth of ~17%, were attained by the antenna. The CP antenna proposed offers a useful gain of ~6.2 dBic. The achieved CP bandwidth of the RDRA is good enough to cover the targeted 5G NR bands around 4.4−4.8 GHz, such as n79. The proposed antenna configuration is modelled and optimized using computer simulation technology (CST). A prototype was built to confirm (validate) the performance estimated through simulation. A good agreement was observed between simulated and measured results.
Frequency and evaluation of the perceptions towards caesarean section among pregnant women attending public hospitals in Pakistan and the implications

Ishaq R, Baloch NS, Iqbal Q, Saleem F, Hassali MA, Iqbal J, et al.

Hosp Pract (1995), 2017 Aug;45(3):104-110.
PMID: 28490205 DOI: 10.1080/21548331.2017.1328250

OBJECTIVES: There is increasing prevalence of caesarean sections (CS) worldwide; however, there are concerns about their rates in some countries, including potential fears among mothers. Consequently, we aimed to determine the frequency of CS, and explore patient's perception towards CS attending public hospitals in Pakistan, to provide future guidance.
METHODS: A two-phased study design (retrospective and cross sectional) was adopted. A retrospective study was conducted to assess the frequency of CS over one year among four public hospitals. A cross sectional study was subsequently conducted to determine patients' perception towards CS attending the four tertiary care public hospitals in Quetta city, Pakistan, which is where most births take place.
RESULTS: Overall prevalence of CS was 13.1% across the four hospitals. 728 patients were approached and 717 responded to the survey. Although 78.8% perceived CS as dangerous, influenced by education (p = 0.004), locality (p = 0.001) and employment status (p = 0.001), 74.5% of patients were in agreement that this is the best approach to save mother's and baby's lives if needed. 62% of respondents reported they would like to avoid CS if they could due to post-operative pain, and 58.9% preferred a normal delivery. There was also a significant association with education (p = 0.001) and locality (p = 0.001) where respondents considered normal vaginal delivery as painful.
CONCLUSION: The overall frequency of CS approximates to WHO recommendations, although there is appreciable variation among the four hospitals. When it comes to perception towards CS, women had limited information. There is a need to provide mothers with education during the antenatal period, especially those with limited education, to accept CS where needed.
Exploring antidiabetic potential of adamantyl-thiosemicarbazones via aldose reductase (ALR2) inhibition

Shehzad MT, Hameed A, Al-Rashida M, Imran A, Uroos M, Asari A, et al.

Bioorg Chem, 2019 11;92:103244.
PMID: 31541804 DOI: 10.1016/j.bioorg.2019.103244

The role of aldose reductase (ALR2) in diabetes mellitus is well-established. Our interest in finding ALR2 inhibitors led us to explore the inhibitory potential of new thiosemicarbazones. In this study, we have synthesized adamantyl-thiosemicarbazones and screened them as aldehyde reductase (ALR1) and aldose reductase (ALR2) inhibitors. The compounds bearing phenyl 3a, 2-methylphenyl 3g and 2,6-dimethylphenyl 3m have been identified as most potent ALR2 inhibitors with IC50 values of 3.99 ± 0.38, 3.55 ± 0.26 and 1.37 ± 0.92 µM, respectively, compared with sorbinil (IC50 = 3.14 ± 0.02 μM). The compounds 3a, 3g, and 3m also inhibit ALR1 with IC50 value of 7.75 ± 0.28, 7.26 ± 0.39 and 7.04 ± 2.23 µM, respectively. Molecular docking was also performed for putative binding of potent inhibitors with target enzyme ALR2. The most potent 2,6-dimethylphenyl bearing thiosemicarbazone 3m (IC50 = 1.37 ± 0.92 µM for ALR2) and other two compound 3a and 3g could potentially lead for the development of new therapeutic agents.
Ultrasonication-assisted synthesis of novel strontium based mixed phase structures for supercapattery devices

Iqbal MZ, Khan A, Numan A, Haider SS, Iqbal J

Ultrason Sonochem, 2019 Dec;59:104736.
PMID: 31473424 DOI: 10.1016/j.ultsonch.2019.104736

An upsurge in sustainable energy demands has ultimately made supercapattery one of the important choice for energy storage, owing to highly advantageous energy density and long life span. In this work, novel strontium based mixed phased nanostructures were synthesized by using probe sonicator with sonication power 500 W at frequency of 20 kHz. The synthesized material was subsequently calcined at different temperature ranging from 200 to 800 °C. Structural and morphological analysis of the synthesized materials reveals the formation of mixed particle and rod like nanostructures with multiple crystal phases of strontium oxides and carbonates. Crystallinity, grain size and morphology of grown nanomaterials significantly improved with the increase of calcination temperature due to sufficient particle growth and low agglomeration. The electrochemical performance analysis confirms the redox activeness of the Sr-based electrode materials. Material calcined at 600 °C show high specific capacitance of 350 F g-1 and specific capacity of 175 C g-1 at current density of 0.3 A g-1 due to less particle agglomeration, good charge transfer and more contribution of electrochemical active sites for redox reactions. In addition, the developed supercapattery of Sr-based nanomaterials//activated carbon demonstrated high performance with maximum energy density of 21.8 Wh kg-1 and an excellent power density of 2400 W kg-1 for the lower and higher current densities. Furthermore, the supercapattery retain 87% of its capacity after continuous 3000 charge/discharge cycles. The device characteristics were further investigated by analyzing the capacitive and diffusion controlled contributions. The versatile strategy of developing mixed phased nanomaterials pave the way to synthesize other transition metal based nanomaterials with superior electrochemical performance for hybrid energy storage devices.
Benzoxazinone-thiosemicarbazones as antidiabetic leads via aldose reductase inhibition: Synthesis, biological screening and molecular docking study

Shehzad MT, Imran A, Njateng GSS, Hameed A, Islam M, Al-Rashida M, et al.

Bioorg Chem, 2019 06;87:857-866.
PMID: 30551808 DOI: 10.1016/j.bioorg.2018.12.006

Aldose reductase is an important enzyme in the polyol pathway, where glucose is converted to fructose, and sorbitol is released. Aldose reductase activity increases in diabetes as the glucose levels increase, resulting in increased sorbitol production. Sorbitol, being less cell permeable tends to accumulate in tissues such as eye lenses, peripheral nerves and glomerulus that are not insulin sensitive. This excessive build-up of sorbitol is responsible for diabetes associated complications such as retinopathy and neuropathy. In continuation of our interest to design and discover potent inhibitors of aldo-keto reductases (AKRs; aldehyde reductase ALR1 or AKR1A, and aldose reductase ALR2 or AKR1B), herein we designed and investigated a series of new benzoxazinone-thiosemicarbazones (3a-r) as ALR2 and ALR1 inhibitors. Most compounds exhibited excellent inhibitory activities with IC50 values in lower micro-molar range. Compounds 3b and 3l were found to be most active ALR2 inhibitors with IC50 values of 0.52 ± 0.04 and 0.19 ± 0.03 μM, respectively, both compounds were more effective inhibitors as compared to the standard ALR2 inhibitor (sorbinil, with IC50 value of 3.14 ± 0.02 μM).
Semicarbazone derivatives as urease inhibitors: Synthesis, biological evaluation, molecular docking studies and in-silico ADME evaluation

Qazi SU, Rahman SU, Awan AN, Al-Rashida M, Alharthy RD, Asari A, et al.

Bioorg Chem, 2018 09;79:19-26.
PMID: 29709568 DOI: 10.1016/j.bioorg.2018.03.029

A series of hydrazinecarboxamide derivatives were synthesized and examined against urease for their inhibitory activity. Among the series, the 1-(3-fluorobenzylidene)semicarbazide (4a) (IC50 = 0.52 ± 0.45 µM), 4u (IC50 = 1.23 ± 0.32 µM) and 4h (IC50 = 2.22 ± 0.32 µM) were found most potent. Furthermore, the molecular docking study was also performed to demonstrate the binding mode of the active hydrazinecarboxamide with the enzyme, urease. In order to estimate drug likeness of compounds, in silico ADME evaluation was carried out. All compounds exhibited favorable ADME profiles with good predicted oral bioavailability.
Synthesis, characterization, monoamine oxidase inhibition, molecular docking and dynamic simulations of novel 2,1-benzothiazine-2,2-dioxide derivatives

Ahmad S, Zaib S, Jalil S, Shafiq M, Ahmad M, Sultan S, et al.

Bioorg Chem, 2018 10;80:498-510.
PMID: 29996111 DOI: 10.1016/j.bioorg.2018.04.012

In this research work, we report the synthesis and biological evaluation of two new series of 1-benzyl-4-(benzylidenehydrazono)-3,4-dihydro-1H-benzo[c] [1,2]thiazine 2,2-dioxides and 1-benzyl-4-((1-phenylethylidene)hydrazono)-3,4-dihydro-1H-benzo[c][1,2]thiazine 2,2-dioxides. The synthetic plan involves the mesylation of methyl anthranilate with subsequent N-benzylation of the product. The methyl 2-(N-benzylmethylsulfonamido)benzoate was subjected to cyclization reaction in the presence of sodium hydride to obtain 1-benzyl-1H-benzo[c][1,2]thiazin-4(3H)-one 2,2-dioxide which was treated with hydrazine hydrate to get corresponding hydrazone precursor. Finally, the titled compounds were obtained by reaction of hydrazone with various substituted aldehydes and ketones. The synthesized derivatives were subjected to carry out their inhibition activities against monoamine oxidases along with modelling investigations to evaluate their binding interactions and dynamic stability during the docking studies. The inhibition profile of potent compounds was found as competitive for both the isozymes. The compounds were more selective inhibitors of MAO-A as compared to MAO-B. Moreover, drug likeness profile of the derivatives was evaluated to have an additional insight into the physicochemical properties. The molecular dynamic simulations predicted the behaviour of amino acids with the active site residues.
Acridine-based (thio)semicarbazones and hydrazones: Synthesis, in vitro urease inhibition, molecular docking and in-silico ADME evaluation

Isaac IO, Al-Rashida M, Rahman SU, Alharthy RD, Asari A, Hameed A, et al.

Bioorg Chem, 2019 02;82:6-16.
PMID: 30267972 DOI: 10.1016/j.bioorg.2018.09.032

Urease is a bacterial enzyme that is responsible for virulence of various pathogenic bacteria such as Staphylococcus aureus, Proteus mirabilis, Klebsiella pneumoniae, Ureaplasma urealyticum, Helicobacter pylori and Mycobacterium tuberculosis. Increased urease activity aids in survival and colonization of pathogenic bacteria causing several disorders especially gastric ulceration. Hence, urease inhibitors are used for treatment of such diseases. In search of new molecules with better urease inhibitory activity, herein we report a series of acridine derived (thio)semicarbazones (4a-4e, 6a-6l) that were found to be active against urease enzyme. Molecular docking studies were carried out to better comprehend the preferential mode of binding of these compounds against urease enzyme. Docking against urease from pathogenic bacterium S. pasteurii was also carried out with favorable results. In silico ADME evaluation was done to determine drug likeness of synthesized compounds.
Synthesis, X-ray crystal and monoamine oxidase inhibitory activity of 4,6-dihydrobenzo[c]pyrano[2,3-e][1,2]thiazine 5,5-dioxides: In vitro studies and docking analysis

Ahmad S, Jalil S, Zaib S, Aslam S, Ahmad M, Rasul A, et al.

Eur J Pharm Sci, 2019 Apr 01;131:9-22.
PMID: 30735822 DOI: 10.1016/j.ejps.2019.02.007

We report the synthesis and biological evaluation of two new series of 2-amino-6-benzyl-4-phenyl-4,6-dihydrobenzo[c]pyrano[2,3-e][1,2]thiazine-3‑carbonitrile 5,5-dioxides and 2-amino-6-methyl-4-phenyl-4,6-dihydrobenzo[c]pyrano[2,3-e][1,2]thiazine-3‑carbonitrile 5,5-dioxides. The synthetic methodology involves a multistep reaction starting with methyl anthranilate which was coupled with methane sulfonyl chloride. The product of the reaction was subjected to N-benzylation and N-methylation reactions followed by ring closure with sodium hydride resulting in the formation of respective 2,1-benzothiazine 2,2-dioxides. These 2,1-benzothiazine precursors were subjected to multicomponent reaction with malononitrile and substituted benzaldehydes for the synthesis of two new series of pyranobenzothiazines (6a-r and 7a-r). The synthesized compounds were screened as selective inhibitors of monoamine oxidase A and monoamine oxidase B. The in vitro results suggested that compound 6d and 7q are the selective inhibitors of monoamine oxidase A, however, the selective and potent inhibitors of monoamine oxidase B included compounds 6h and 7r. Moreover, some dual inhibitors were noticed like 7l having more inhibitory activity towards both the isozymes. Moreover, the binding modes of the selective and potent inhibitors of monoamine oxidase A and B were investigated by molecular docking analysis. The results suggested that the synthetic derivatives may be potential towards the monoamine oxidase isozymes.
Fulltext Innovation in Chinese internet companies: A meta-frontier analysis

Hafeez S, Arshad NI, Rahim LBAB, Shabbir MF, Iqbal J

PLoS One, 2020;15(5):e0233278.
PMID: 32437383 DOI: 10.1371/journal.pone.0233278

The innovation of a particular company benefits the whole industry when innovation technology transfers to others. Similarly, the development and innovation in internet companies influence the development and innovation of the industry. This investigation has applied a unique approach of meta-frontier analysis to estimate and analyze the innovation in internet companies in China. A unique dataset of Chinese internet companies from 2000 to 2017 has been utilized to estimate and compare the innovation over the period of study. The change in technology gap ratio (TGR) and a shift in production function have translated into innovation which was overlooked by previous studies. It is found that the production function of internet companies is moving upward in the presence of external factors such as smartphones invention, mobile internet, mobile payments, and artificial intelligence, etc. Consequently, a sudden increase in TGR is captured due to the innovation of some companies. Hence, the average TE of the industry falls caused by the increased distance of other companies form industry production function. However, the innovation advantage defused when other companies start imitating and the average TE elevates. A steady increase in the TGR index revealed that the continuous innovation-based growth of some companies lifting the production frontier upward. This provides the opportunity for other companies to imitate and provides continuous growth in the industry. This study provides a novel methodological approach to measure innovation and also provide practical implication by empirical estimation of innovation in Chinese internet companies.
Fabrication and dialysis performance of functionalized multiwall carbon nanotubes integrated cellulose acetate/poly(vinylpyrrolidone) membranes

Ashraf MA, Islam A, Butt MA, Hussain T, Khan RU, Bashir S, et al.

Int J Biol Macromol, 2021 Nov 30;191:872-880.
PMID: 34571131 DOI: 10.1016/j.ijbiomac.2021.09.131

Mixed matrix membranes (MMMs) of cellulose acetate/poly(vinylpyrrolidone) (CA/PVP) infused with acid functionalized multiwall carbon nanotubes (f-MWCNTs) were fabricated by an immersion phase separation technique for hemodialysis application. Membranes were characterized using FTIR, water uptake, contact angle, TGA, DMA and SEM analysis. The FTIR was used to confirm the bonding interaction between CA/PVP membrane matrix and f-MWCNTs. Upon addition of f-MWCNTs, TGA thermograms and glass transition temperature indicated improved thermal stability of MMMs. The surface morphological analysis demonstrated revealed uniform distribution of f-MWCNTs and asymmetric membrane structure. The water uptake and contact angle confirmed that hydrophilicity was increased after incorporation of f-MWCNTs. The membranes demonstrated enhancement in water permeate flux, bovine serum albumin (BSA) rejection with the infusion of f-MWCNTs; whereas BSA based anti-fouling analysis using flux recovery ratio test shown up to 8.4% improvement. The urea and creatinine clearance performance of MMMs were evaluated by dialysis experiment. It has been found that f-MWCNTs integrated membranes demonstrated the higher urea and creatinine clearance with increase of 12.6% and 10.5% in comparison to the neat CA/PVP membrane. Thus, the prepared CA/PVP membranes embedded with f-MWCNTs can be employed for wide range of dialysis applications.
Synthesis, monoamine oxidase inhibition activity and molecular docking studies of novel 4-hydroxy-N'-[benzylidene or 1-phenylethylidene]-2-H/methyl/benzyl-1,2-benzothiazine-3-carbohydrazide 1,1-dioxides

Saddique FA, Zaib S, Jalil S, Aslam S, Ahmad M, Sultan S, et al.

Eur J Med Chem, 2018 Jan 01;143:1373-1386.
PMID: 29126721 DOI: 10.1016/j.ejmech.2017.10.036

Three series of 4-hydroxy-N'-[benzylidene/1-phenylethylidene]-2-H/methyl/benzyl-1,2-benzothiazine-3-carbohydrazide 1,1-dioxides (9-11)a-l were synthesized and unraveled to be highly potent dual inhibitors of monoamine oxidases (MAO-A and MAO-B). All the examined compounds demonstrated IC50 values in lower micro-molar range for both MAO-A as well as MAO-B. The most active MAO-A inhibitor was 4-hydroxy-N'-(1-phenylethylidene)-2H-benzo[e][1,2]thiazine-3-carbohydrazide 1,1-dioxide (9i) with an IC50 value of 0.11 ± 0.005 μM, whereas, methyl 4-hydroxy-2H-benzo[e][1,2]thiazine-3-carboxylate 1,1-dioxide (3) was the most active MAO-B inhibitor with an IC50 value of 0.21 ± 0.01 μM. Enzyme kinetics studies revealed that the most potent compounds inhibited both MAO enzymes (A & B) in a competitive fashion. Molecular docking studies were also performed to obtain an intuitive picture of inhibition potential for potent inhibitors. The high potency of these compounds is optimally combined with highly favorable ADME profile with predicted good oral bioavailability.
Fulltext Poly (Vinyl Alcohol)/Agar Hydrogel Electrolytes Based Flexible All-in-One Supercapacitors with Conducting Polyaniline/Polypyrrole Electrodes

Hasan K, Bashir S, Subramaniam R, Kasi R, Kamran K, Iqbal J, et al.

Polymers (Basel), 2022 Nov 07;14(21).
PMID: 36365772 DOI: 10.3390/polym14214784

The major components of supercapacitor are electrodes and electrolytes which are fabricated using various materials and methods. Hydrogel is one such material that is used in supercapacitors as electrodes and electrolytes or both. Hydrogels are usually described as a soft and porous network of polymer materials that can swell in water because of the hydrophilic nature of its polymer chains, compriseng a 3D structure. It is well known that supercapacitors possess high-power density but low energy density. For enhancing energy density of these electrochemical cells and a boost in its electrochemical performance and specific capacity, binder free conducting polymer hydrogel electrodes have gained immense attention, especially polyaniline (PANI) and polypyrrole (PPy). Therefore, in this work, chemically crosslinked PVA/Agar hydrogel electrolytes have been prepared and employed. Agar has been added in PVA since it is environmentally friendly, biodegradable, and cost-effective natural polymer. Subsequently, the binder free polyaniline/polypyrrole electrodes were grown on the PVA/Agar hydrogel electrolytes to fabricate all-in-one flexible hydrogels. The synthesized hydrogels were characterized using X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) analysis, Field emission scanning electron microscope (FESEM) and mechanical studies. Then, the all-in-one flexible supercapacitors were fabricated using the hydrogels. The electrochemical studies such cyclic voltammetry (CV), galvanic charge discharge (GCD), and electrochemical impedance spectroscopy (EIS) studies. The fabricated all-in-one lamination free supercapacitors showed promising results and by comparing all four samples, PAP2 where 5 mL of PVA was used in combination with 3 mL of Agar and 5 mL of PANI and PPy each, exhibited the highest areal capacitance of 750.13 mF/cm2, energy density of 103.02 μWh/cm2, and 497.22 μW/cm2 power density. The cyclic stability study revealed the 149% capacity retention after 15,000 cycles.

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