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Synthesis, in vitro evaluation and molecular docking studies of thiazole derivatives as new inhibitors of α-glucosidase

Rahim F, Ullah H, Javid MT, Wadood A, Taha M, Ashraf M, et al.

Bioorg Chem, 2015 Oct;62:15-21.
PMID: 26162519 DOI: 10.1016/j.bioorg.2015.06.006

A series of thiazole derivatives 1-21 were prepared, characterized by EI-MS and (1)H NMR and evaluated for α-glucosidase inhibitory potential. All twenty one derivatives showed good α-glucosidase inhibitory activity with IC50 value ranging between 18.23±0.03 and 424.41±0.94μM when compared with the standard acarbose (IC50, 38.25±0.12μM). Compound (8) (IC50, 18.23±0.03μM) and compound (7) (IC50=36.75±0.05μM) exhibited outstanding inhibitory potential much better than the standard acarbose (IC50, 38.25±0.12μM). All other analogs also showed good to moderate enzyme inhibition. Molecular docking studies were carried out in order to find the binding affinity of thiazole derivatives with enzyme. Studies showed these thiazole analogs as a new class of α-glucosidase inhibitors.
Synthesis and in vitro acetylcholinesterase and butyrylcholinesterase inhibitory potential of hydrazide based Schiff bases

Rahim F, Ullah H, Taha M, Wadood A, Javed MT, Rehman W, et al.

Bioorg Chem, 2016 10;68:30-40.
PMID: 27441832 DOI: 10.1016/j.bioorg.2016.07.005

To discover multifunctional agents for the treatment of Alzheimer's disease, a series of hydrazide based Schiff bases were designed and synthesized based on multitarget-directed strategy. We have synthesized twenty-eight analogs of hydrazide based Schiff bases, characterized by various spectroscopic techniques and evaluated in vitro for acetylcholinesterase and butyrylcholinesterase inhibition. All compounds showed varied degree of acetylcholinesterase and butyrylcholinesterase inhibition when compared with standard Eserine. Among the series, compounds 10, 3 and 24 having IC50 values 4.12±0.01, 8.12±0.01 and 8.41±0.06μM respectively showed potent acetylcholinesterase inhibition when compared with Eserine (IC50=0.85±0.0001μM). Three compounds 13, 24 and 3 having IC50 values 6.51±0.01, 9.22±0.07 and 37.82±0.14μM respectively showed potent butyrylcholinesterase inhibition by comparing with eserine (IC50=0.04±0.0001μM). The remaining compounds also exhibited moderate to weak inhibitory potential. Structure activity relationship has been established. Through molecular docking studies the binding interaction was confirmed.
Performance evaluation of phosphonium based deep eutectic solvents coated cerium oxide nanoparticles for CO2 capture

Ahmad T, Iqbal J, Bustam MA, Babar M, Tahir MB, Sagir M, et al.

Environ Res, 2023 Apr 01;222:115314.
PMID: 36738770 DOI: 10.1016/j.envres.2023.115314

The critical challenge being faced by our current modern society on a global scale is to reduce the surging effects of climate change and global warming, being caused by anthropogenic emissions of CO2 in the environment. Present study reports the surface driven adsorption potential of deep eutectic solvents (DESs) surface functionalized cerium oxide nanoparticles (CeNPs) for low pressure CO2 separation. The phosphonium based DESs were prepared using tetra butyl phosphoniumbromide as hydrogen bond acceptor (HBA) and 6 acids as hydrogen bond donors (HBDs). The as-developed DESs were characterized and employed for the surface functionalization of CeNPs with their subsequent utilization in adsorption-based CO2 adsorption. The synthesis of as-prepared DESs was confirmed through FTIR measurements and absence of precipitates, revealed through visual observations. It was found that DES6 surface functionalized CeNPs demonstrated 27% higher adsorption performance for CO2 capturing. On the contrary, DES3 coated CeNPs exhibited the least adsorption progress for CO2 separation. The higher adsorption performance associated with DES6 coated CeNPs was due to enhanced surface affinity with CO2 molecules that must have facilitated the mass transport characteristics and resulted an enhancement in CO2 adsorption performance. Carboxylic groups could have generated an electric field inside the pores to attract more polarizable adsorbates including CO2, are responsible for the relatively high values of CO2 adsorption. The quadruple movement of the CO2 molecules with the electron-deficient and pluralizable nature led to the enhancement of the interactive forces between the CO2 molecules and the CeNPs decorated with the carboxylic group hydrogen bond donor rich DES. The current findings may disclose the new research horizons and theoretical guidance for reduction in the environmental effects associated with uncontrolled CO2 emission via employing DES surface coated potential CeNPs.
Fulltext Potential biosorbent derived from Calligonum polygonoides for removal of methylene blue dye from aqueous solution

Nasrullah A, Khan H, Khan AS, Man Z, Muhammad N, Khan MI, et al.

ScientificWorldJournal, 2015;2015:562693.
PMID: 25705714 DOI: 10.1155/2015/562693

The ash of C. polygonoides (locally called balanza) was collected from Lakki Marwat, Khyber Pakhtunkhwa, Pakistan, and was utilized as biosorbent for methylene blue (MB) removal from aqueous solution. The ash was used as biosorbent without any physical or chemical treatment. The biosorbent was characterized by using various techniques such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The particle size and surface area were measured using particle size analyzer and Brunauer-Emmett-Teller equation (BET), respectively. The SEM and BET results expressed that the adsorbent has porous nature. Effects of various conditions such as initial concentration of methylene blue (MB), initial pH, contact time, dosage of biosorbent, and stirring rate were also investigated for the adsorption process. The rate of the adsorption of MB on biomass sample was fast, and equilibrium has been achieved within 1 hour. The kinetics of MB adsorption on biosorbent was studied by pseudo-first- and pseudo-second-order kinetic models and the pseudo-second-order has better mathematical fit with correlation coefficient value (R (2)) of 0.999. The study revealed that C. polygonoides ash proved to be an effective, alternative, inexpensive, and environmentally benign biosorbent for MB removal from aqueous solution.
Fulltext Impact of tuberculosis treatment on health-related quality of life of pulmonary tuberculosis patients: a follow-up study

Atif M, Sulaiman SA, Shafie AA, Asif M, Sarfraz MK, Low HC, et al.

Health Qual Life Outcomes, 2014;12:19.
PMID: 24528499 DOI: 10.1186/1477-7525-12-19

At present, much of the attention within tuberculosis (TB) management is spent on microbiological cure, and its impact on health-related quality of life (HRQoL) is either undervalued or seldom considered. The aim of this study was to evaluate the impact of TB treatment on HRQoL of new smear positive pulmonary tuberculosis (PTB) patients. Moreover, we also aimed to determine whether the selected socio-demographic and clinical variables were predictive of variability in the HRQoL scores over time.
Evaluation of BV(®) Blue Test Kit for the diagnosis of bacterial vaginosis

Kampan NC, Suffian SS, Ithnin NS, Muhammad M, Zakaria SZ, Jamil MA

Sex Reprod Healthc, 2011 Jan;2(1):1-5.
PMID: 21147452 DOI: 10.1016/j.srhc.2010.11.002

The aim of this study is to determine the sensitivity, specificity and the predictive value of the BV(®) Blue Test Kit in the diagnosis of bacterial vaginosis and to observe the risk factors associated with bacterial vaginosis (BV) in the study population. A prospective, cross-sectional study on 151 non-pregnant women who presented or referred to HUKM with presence of vaginal discharge, abnormal vaginal odour, pruritus vulvae of lower genital tract or incidental finding of abnormal PV discharge on pelvic examination. Samples of vaginal discharge were tested for bacterial vaginosis infection using Amsel's criteria, BV(®) Blue test and Gram stain (Nugent's score). Gram stain interpretation was made blinded without knowledge of other test result. Using Gram stain's criteria as a gold standard, the sensitivity, specificity, positive and negative predictive value of BV(®) Blue test and each of Amsel's criteria were estimated. The use of vaginal douches increased the risk of BV. The risk of BV with vaginal douching was 2.8 (95% CI 1.0-7.8) compared to never users. BV(®) Blue test showed a sensitivity of 100.0%, specificity of 98.3%, positive predictive value (PPV) of 94.4% and negative predictive value (NPV) of 100.0% compared to Gram stain (Nugent's method). BV(®) Blue test had excellent agreement with Gram stain which was 98.7%. BV(®) Blue test is a simple, rapid and reliable test allowing immediate diagnosis and prompt treatment of BV in the absence of microscopy which would greatly benefit majority of women at the greatest risk of sequel of bacterial vaginosis.
Synthesis of novel flavone hydrazones: in-vitro evaluation of α-glucosidase inhibition, QSAR analysis and docking studies

Imran S, Taha M, Ismail NH, Kashif SM, Rahim F, Jamil W, et al.

Eur J Med Chem, 2015 Nov 13;105:156-70.
PMID: 26491979 DOI: 10.1016/j.ejmech.2015.10.017

Thirty derivatives of flavone hydrazone (5-34) had been synthesized through a five-step reaction and screened for their α-glucosidase inhibition activity. Chalcone 1 was synthesized through aldol condensation then subjected through oxidative cyclization, esterification, and condensation reaction to afford the final products. The result for baker's yeast α-glucosidase (EC 3.2.1.20) inhibition assay showed that all compounds are active with reference to the IC50 value of the acarbose (standard drug) except for compound 3. Increase in activity observed for compounds 2 to 34 clearly highlights the importance of flavone, hydrazide and hydrazone linkage in suppressing the activity of α-glucosidase. Additional functional group on N-benzylidene moiety further enhances the activity significantly. Compound 5 (15.4 ± 0.22 μM), a 2,4,6-trihydroxy substituted compound, is the most active compound in the series. Other compounds which were found to be active are those having chlorine, fluorine, and nitro substituents. Compounds with methoxy, pyridine, and methyl substituents are weakly active. Further studies showed that they are not active in inhibiting histone deacetylase activity and do not possess any cytotoxic properties. QSAR model was being developed to further identify the structural requirements contributing to the activity. Using Discovery Studio (DS) 2.5, various 2D descriptors were being used to develop the model. The QSAR model is able to predict the pIC50 and could be used as a prediction tool for compounds having the same skeletal framework. Molecular docking was done for all compounds using homology model of α-glucosidase to identify important binding modes responsible for inhibition activity.
Hybrid benzothiazole analogs as antiurease agent: Synthesis and molecular docking studies

Taha M, Ismail NH, Imran S, Wadood A, Rahim F, Khan KM, et al.

Bioorg Chem, 2016 Jun;66:80-7.
PMID: 27038849 DOI: 10.1016/j.bioorg.2016.03.010

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.
Fulltext Induction of apoptosis and role of paclitaxel-loaded hyaluronic acid-crosslinked nanoparticles in the regulation of AKT and RhoA

Chaudhry GE, Akim A, Zafar MN, Abdullah MA, Sung YY, Muhammad TST

J Adv Pharm Technol Res, 2020 07 14;11(3):101-106.
PMID: 33102192 DOI: 10.4103/japtr.JAPTR_26_20

Cancer is a complex multifactorial disease and leading causes of death worldwide. Despite the development of many anticancer drugs, there is a reduced survival rate due to severe side effects. The nontargeted approach of convention drugs is one of the leading players in context to toxicity. Hyaluronan is a versatile bio-polymer and ligand of the receptor (CD44) on cancer cells. The MCF-7 and HT-29 cancer cell lines treated with hyaluronic acid-paclitaxel (HA-PTX) showed the distinguishing morphological features of apoptosis. Flow cytometric analysis showed that HA-PTX induces apoptosis as a significant mode of cell death. The activation level of tumor suppressor protein (p53) increased after PTX treatment in MCF-7, but no changes observed in HT-29 might be due to hereditary mutations. The lack of suppression in AKT and Rho A protein suggest the use of possible inhibitors in future studies which might could play a role in increasing the sensitivity of drug towards mutated cells line and reducing the possibilities for cancer cell survival, migration, and metastasis.
Mechanistic investigation of phytochemicals involved in green synthesis of gold nanoparticles using aqueous Elaeis guineensis leaves extract: Role of phenolic compounds and flavonoids

Ahmad T, Bustam MA, Irfan M, Moniruzzaman M, Asghar HMA, Bhattacharjee S

Biotechnol Appl Biochem, 2019 Jul;66(4):698-708.
PMID: 31172593 DOI: 10.1002/bab.1787

Phytosynthesis of gold nanoparticles (AuNPs) has achieved an indispensable significance due to the diverse roles played by biomolecules in directing the physiochemical characteristics of biosynthesized nanoparticles. Therefore, the precise identification of key bioactive compounds involved in producing AuNPs is vital to control their tunable characteristics for potential applications. Herein, qualitative and quantitative determination of key biocompounds contributing to the formation of AuNPs using aqueous Elaeis guineensis leaves extract is reported. Moreover, roles of phenolic compounds and flavonoids in reduction of Au3+ and stabilization of AuNPs have been elucidated by establishing a reaction mechanism. Fourier-transform infrared spectroscopy (FTIR) showed shifting of O─H stretching vibrations toward longer wavenumbers and C═O toward shorter wavenumbers due to involvement of polyphenolic compounds in biosynthesis and oxidation of polyphenolic into carboxylic compounds, respectively, which cape nanoparticles to inhibit the aggregation. Congruently, pyrolysis-gas chromatography-mass spectrometry revealed the major contribution of polyphenolic compounds in the synthesis of AuNPs, which was further endorsed by reduction of total phenolic and total flavonoids contents from 48.08 ± 1.98 to 9.59 ± 0.92 mg GAE/g and 32.02 ± 1.31 to 13.8 ± 0.97 mg CE/g within 60 Min, respectively. Based on experimental results, reaction mechanism explained the roles of phenolic compounds and flavonoids in producing spherical-shaped AuNPs.
Fulltext Protective effects of stem cells from human exfoliated deciduous teeth derived conditioned medium on osteoarthritic chondrocytes

Muhammad SA, Nordin N, Hussin P, Mehat MZ, Abu Kasim NH, Fakurazi S

PLoS One, 2020;15(9):e0238449.
PMID: 32886713 DOI: 10.1371/journal.pone.0238449

Treatment of osteoarthritis (OA) is still a major clinical challenge due to the limited inherent healing capacity of cartilage. Recent studies utilising stem cells suggest that the therapeutic benefits of these cells are mediated through the paracrine mechanism of bioactive molecules. The present study evaluates the regenerative effect of stem cells from human exfoliated deciduous teeth (SHED) conditioned medium (CM) on OA chondrocytes. The CM was collected after the SHED were cultured in serum-free medium (SFM) for 48 or 72 h and the cells were characterised by the expression of MSC and pluripotency markers. Chondrocytes were stimulated with interleukin-1β and treated with the CM. Subsequently, the expression of aggrecan, collagen type 2 (COL 2), matrix metalloproteinase-13 (MMP-13), nuclear factor-kB (NF-kB) and the level of inflammatory and anti-inflammatory markers were evaluated. SHED expressed mesenchymal stromal cell surface proteins but were negative for haematopoietic markers. SHED also showed protein expression of NANOG, OCT4 and SOX2 with differential subcellular localisation. Treatment of OA chondrocytes with CM enhanced anti-inflammation compared to control cells treated with SFM. Furthermore, the expression of MMP-13 and NF-kB was significantly downregulated in stimulated chondrocytes incubated in CM. The study also revealed that CM increased the expression of aggrecan and COL 2 in OA chondrocytes compared to SFM control. Both CM regenerate extracellular matrix proteins and mitigate increased MMP-13 expression through inhibition of NF-kB in OA chondrocytes due to the presence of bioactive molecules. The study underscores the potential of CM for OA treatment.
Fulltext Comparison of doxorubicin anticancer drug loading on different metal oxide nanoparticles

Javed KR, Ahmad M, Ali S, Butt MZ, Nafees M, Butt AR, et al.

Medicine (Baltimore), 2015 Mar;94(11):e617.
PMID: 25789952 DOI: 10.1097/MD.0000000000000617

Nanomaterials are being vigorously investigated for their use in anticancer drug delivery regimes or as biomarkers agents and are considered to be a candidate to provide a way to combat severe weaknesses of anticancer drug pharmacokinetics, such as their nonspecificity. Because of this weakness, a bigger proportion of the drug-loaded nanomaterials flow toward healthy tissues and result in undesirable side effects. It is very important to evaluate drug loading and release efficiency of various nanomaterials to find out true pharmacokinetics of these drugs.This observational study aims to evaluate various surface functionalized and naked nanomaterials for their drug loading capability and consequently strengthens the Reporting of Observational Studies in Epidemiology (STROBE). We analyzed naked and coated nanoparticles of transition metal oxides for their further loading with doxorubicin, a representative water-soluble anticancer drug.Various uncoated and polyethylene glycol-coated metal oxide nanoparticles were synthesized and loaded with anticancer drug using simple stirring of the nanoparticles in a saturated aqueous solution of the drug. Results showed that surface-coated nanoparticles have higher drug-loading capabilities; however, certain naked metal oxide nanoparticles, such as cobalt oxide nanoparticles, can load a sufficient amount of drug.
Fulltext House building tips (HBT) corpus dataset as a resource to discover Malay architectural ingenuity and identity

Zaini MF, Sarudin A, Muhammad MM, Osman Z, Mohamed Redzwan HF, Al-Muhsin MA

Data Brief, 2021 Jun;36:107013.
PMID: 33898671 DOI: 10.1016/j.dib.2021.107013

House Building Tips is the title of a classic text containing historical information on early house construction in Malay communities. These tips were written by a scholar with knowledge of house construction through observation of the surrounding environment. In Malaysia, written sources or records of house construction are scarce and underexposed. As such, this research was conducted to guarantee the written legacy of the construction of Malay houses. The purpose of this paper is to introduce a statistical data source of house building tips that is laden with Malay ingenuity and identity. The wordlists generated from this study can become a source of reference for the field of Malay architecture. Accordingly, this study utilises the quantitative method by applying the Linguistic Corpus Statistical Approach; these data utilise specific corpus development procedures, beginning with text collection, scanning and cleaning processes, text annotation, and data storing in plain text. Next, the data analysis procedure utilises a corpus software, LancsBox, to generate specialised wordlists. The bubble graphs are developed based on these wordlists through the Tableau software, and illustrate the most used lexical items with the raw and relative frequency values. This facilitates searches for, and the reading of, architectural words and architectural word references. These data represent written sources that need to be preserved and become points of reference concerning Malay architectural ingenuity and identity.
Fulltext Microvessel density and vascular endothelial growth factor receptors in breast carcinoma under the influence of rapamycin and platelet factor 4

Muhammad Sakri MS, Abdul Rahman WFW, Tengku Din TADA, Idris FM, Jaafar H

Indian J Pathol Microbiol, 2020 4 23;63(2):205-209.
PMID: 32317516 DOI: 10.4103/IJPM.IJPM_496_19

Background: Vascular endothelial growth factor receptors (VEGFRs) are major endothelial growth factor receptors that influence the growth of a tumor. Microvessel density.
(: MVD) is the quantification method of various aspects of tumor vasculature that indicates angiogenic activity. This study aims to analyze the correlation between MVD to the expression of VEGFRs on breast cancer tissue.
Materials and Method: A total of 60 N-methyl-N-nitrosourea (MNU)-induced breast carcinomas in rats were suppressed by using antiangiogenic drugs. The rats were then sacrificed, and the tumor was fixed in 10% formalin, paraffin embedded, and immunohistochemistry stained using VEGFRs and CD34.
Result: One-way ANOVA test showed a significant difference in all markers that have been used (P < 0.05) on MNU-breast tumor treated with rapamycin (M= 90.1664, SD= 7.4487), PF4 (M= 93.7946, SD= 7.1303) and rapamycin + PF4 (M= 93.6990, SD= 1.8432). We obtained a significant reduction of MVD count on breast carcinoma for rapamycin group (M= 25.6786, SD= 9.7075) and rapamycin + PF4 group (M= 30.5250, SD= 13.6928) while PF4 group (M=47.7985, SD=4.8892) showed slightly increase compared to control (M= 45.1875, SD= 4.4786). There was a moderately strong, positive correlation between angiogenic markers; Flt-1 (r= 0.544, n=60, P < 0.005) and Flt-4 (r= 0.555, n= 60, P < 0.005) while Flk-1 (r= 0.797, n= 60, P < 0.005) showed a strong, positive correlation with MVD.
Conclusion: MVD was strongly correlated to the VEGFRs expression on breast carcinoma.
Fulltext Evaluation of NMU-Induced Breast Cancer Treated with Sirolimus and Sunitinib on Breast Cancer Growth

Jaffar NFN, Muhammad Sakri MS, Jaafar H, Wan Abdul Rahman WF, Tengku Din TADA

Asian Pac J Cancer Prev, 2020 Oct 01;21(10):2919-2925.
PMID: 33112549 DOI: 10.31557/APJCP.2020.21.10.2919

OBJECTIVE: To analyze the effect of sirolimus and sunitinib in blocking the tumor growth and to evaluate the expressions of estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor-2 (HER2/neu) after treated with sirolimus and sunitinib.
METHODS: Thirty-two female Sprague Dawley rats at age 21-days old were administered intraperitoneally with N-Methyl-N-Nitroso Urea (NMU), dosed at 70mg/kg body weight. The rats were divided into 4 groups; Group 1 (Control, n=8), Group 2 (Sirolimus, n=8), Group 3 (Sunitinib, n=8) and Group 4 (Sirolimus+Sunitinib, n=8), being treated twice when the tumor reached the size of 14.5±0.5 mm and subsequently sacrificed after 5 days. The protein expressions of ER, PgR and HER2/neu of the tumor tissues were evaluated by using immunohistochemistry analysis.
RESULTS: Treatment with sirolimus alone lowered expressions of ER and PgR of breast cancer and reduced tumor size. There was no significant difference of ER and PgR expressions between control and sunitinib treated tumor. Sunitinib treated tumors reduce in diameter after the first treatment, however the diameter increases after the second treatment. Histologically, sunitinib treated tumor did not show any aggressive invasive carcinoma of no special type (NST) histological subtypes. In addition, all NMU-induced tumors are HER2/neu-negative scoring.
CONCLUSION: Sirolimus is neither synergistic nor additive with sunitinib for breast cancer treatment.
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Fulltext Chemically Modified Quinoidal Oligothiophenes for Enhanced Linear and Third-Order Nonlinear Optical Properties

Bibi A, Muhammad S, UrRehman S, Bibi S, Bashir S, Ayub K, et al.

ACS Omega, 2021 Sep 28;6(38):24602-24613.
PMID: 34604642 DOI: 10.1021/acsomega.1c03218

In the present investigation, quantum chemical calculations have been performed in a systematic way to explore the optoelectronic, charge transfer, and nonlinear optical (NLO) properties of different bis(dicyanomethylene) end-functionalized quinoidal oligothiophenes. The effect of different conformations (linking modes of thiophene rings) on conformational, optoelectronic, and NLO properties are studied from the best-performed dimer to octamer. The optical and NLO properties of all the selected systems (1-7) are calculated by means of density functional theory (DFT) methods. Among all the designed compounds, the largest linear isotropic (αiso) polarizability value of 603.1 × 10-24 esu is shown by compound 7 which is ∼12, ∼16, ∼9, ∼11, ∼10, and ∼4 times larger as compared to compounds 1-6, respectively. A relative investigation is performed considering the expansion in third-order NLO polarizability as a function of size and conformational modes. Among all the investigated systems, system 7 shows the highest value of static second hyperpolarizability ⟨γ⟩ with an amplitude of 7607 × 10-36 esu at the M06/6-311G** level of theory, which is ∼521, ∼505, ∼38, ∼884, ∼185, and ∼15 times more than that of compounds 1-6, respectively. The extensively larger ⟨γ⟩ amplitude of compound 7 with higher oscillator strength and lower transition energy indicates that NLO properties are remarkably dependent upon linking modes of thiophene rings and its chain length. Furthermore, to trace the origin of higher nonlinearities, TD-DFT calculations are also performed at the same TD-M06/6-311G** level of theory. Additionally, a comprehensive understanding of the effect of structure/property relationship on the NLO polarizabilities of these investigated quinoidal oligothiophenes is obtained through the inspection of Frontier molecular orbitals, the density of states (TDOS and PDOS), and molecular electrostatic potential diagrams including the transition density matrix. Hence, the current examination will not just feature the NLO capability of entitled compounds yet additionally incite the interest of experimentalists to adequately modify the structure of these oligothiophenes for efficient optical and NLO applications.
A study on the spectroscopic, energy band, and optoelectronic properties of α,ω-dihexylsexithiophene/tris(8-hydroxyquinolinate) gallium blends; DH6T/Gaq3 composite system

Muhammad FF, Yahya MY, Ketuly KA, Muhammad AJ, Sulaiman K

Spectrochim Acta A Mol Biomol Spectrosc, 2016 Dec 05;169:144-51.
PMID: 27372510 DOI: 10.1016/j.saa.2016.06.031

In this work the optical response, spectroscopic behaviour, and optoelectronic properties of solution and solid state composite systems based on α,ω-dihexylsexithiophene/tris(8-hydroxyquinolinate) gallium (DH6T/Gaq3) are studied upon the incorporation of different molar percentages of Gaq3. UV-vis, PL, FTIR spectrophotometers and SEM technique were utilized to perform the investigations. The results showed a reduced energy band (Eg) (from 2.33eV to 1.83eV) and a broadened absorption spectrum for the blend system when 29.8% molar of Gaq3 was incorporated. These were attributed to the enhanced intermolecular interactions that are brought about by the increased strength of π-π overlap between the molecular moieties. A mathematical formula was developed to interpret the non-monotonic change occurred in Eg, while numerical calculations have been made to assign the type and nature of the electronic transitions governing the spectroscopic behaviour of the system. The results were elaborated and comprehensively discussed in terms of the exciton generation, energy band theory, molecular interactions, and spatial geometry.
Designing novel bioconjugates of hydroxyethyl cellulose and salicylates for potential pharmaceutical and pharmacological applications

Abbas K, Amin M, Hussain MA, Sher M, Bukhari SNA, Jantan I, et al.

Int J Biol Macromol, 2017 Oct;103:441-450.
PMID: 28526350 DOI: 10.1016/j.ijbiomac.2017.05.061

This deals with fabrication of macromolecular prodrugs (MPDs) of salicylic acid (SA) and aspirin (ASP) based on a hydrophilic cellulose ether, hydroxyethyl cellulose (HEC). Degrees of substitution (DS) of SA and ASP per HEC repeating unit (HEC-RU) were achieved ranging from 0.60 to 2.18 and 0.53 to1.50, respectively. The amphiphilic HEC-SA conjugate 2 assembled into nanowire-like structures, while HEC-ASP conjugate 6 formed nanoparticles (diameter 300-00nm) at a water/DMSO interface. After oral administration in rabbit models, conjugates 2 and 6 showed plasma half-life of 6.96 and 7.01h with maximum plasma concentration (Cmax) of 15.27 and 23.01μg L-1, respectively, and each reached peak plasma concentration (tmax) at 4.0h. Immunomodulatory assays (interleukin 6 and tumor necrosis factor-α values) revealed that anti-inflammatory properties of SA and ASP were unaltered in conjugates. Swelling inhibition of 61 and 71% was observed for conjugates 2 and 6, respectively, in a carrageenan induced paw edema test. Cytotoxic profiling (MTT assay) showed that conjugates were safe for administration in the concentration range of 2-10mM up to 24h. Thermal analyses revealed that Tdm values of SA and ASP conjugates were increased by 99 and 154̊C, respectively, indicating extraordinary thermal stability imparted to drugs after MPD formation.
Synthesis of indole analogs as potent β-glucuronidase inhibitors

Baharudin MS, Taha M, Imran S, Ismail NH, Rahim F, Javid MT, et al.

Bioorg Chem, 2017 06;72:323-332.
PMID: 28505547 DOI: 10.1016/j.bioorg.2017.05.005

Natural products are the main source of motivation to design and synthesize new molecules for drug development. Designing new molecules against β-glucuronidase inhibitory is utmost essential. In this study indole analogs (1-35) were synthesized, characterized using various spectroscopic techniques including 1H NMR and EI-MS and evaluated for their β-glucuronidase inhibitory activity. Most compounds were identified as potent inhibitors for the enzyme with IC50 values ranging between 0.50 and 53.40μM, with reference to standard d-saccharic acid 1,4-lactone (IC50=48.4±1.25μM). Structure-activity relationship had been also established. The results obtained from docking studies for the most active compound 10 showed that hydrogen bond donor features as well as hydrogen bonding with (Oε1) of nucleophilic residue Glu540 is believed to be the most importance interaction in the inhibition activity. It was also observed that hydroxyl at fourth position of benzylidene ring acts as a hydrogen bond donor and interacts with hydroxyl (OH) on the side chain of catalysis residue Tyr508. The enzyme-ligand complexed were being stabilized through electrostatic π-anion interaction with acid-base catalyst Glu451 (3.96Å) and thus preventing Glu451 from functioning as proton donor residue.
Hepatoprotective activity of viscosine is mediated by attenuation of hepatic macrophages and iNOS expression in CCl4-intoxicated rats

Ali H, Kabir N, Shah MR, Muhammad A, Ali S, Mehmood S, et al.

Toxicol Res (Camb), 2016 Nov 01;5(6):1688-1698.
PMID: 30090468 DOI: 10.1039/c6tx00165c

This study investigated the molecular mechanism(s) of the protective effects of a C-alkylated flavonoid, viscosine on an animal model of CCl4-induced hepatotoxicity. Viscosine at 20, 50 and 100 mg kg-1 was orally administered in a dose dependent manner per day for 3 days before the CCl4 (1 : 1 v/v in olive oil, 1 ml kg-1) treatment and 2 days after the treatment. Hepatoprotection was assessed in terms of reduction in serum enzyme activities (ALT, AST, and ALP) that occur after CCl4 injury, and by histopathology and immunohistochemistry. The rise in serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in CCl4-intoxicated rats was markedly suppressed by viscosine in a concentration dependent manner. The decrease in the activity of hepatic antioxidant enzyme, SOD, was significantly prevented by viscosine, likewise gradually the levels of MDA and GSH were also normalized compared to silymarin. Viscosine also reduced the CCl4-induced damaged area from 2% to 0% as assessed by histopathology and prevented the mixed inflammatory infiltrate. Viscosine attenuated the inflammation in the liver around the injured central vein region by downregulating the CCl4 induced activation of hepatic CD68+ macrophages, thereby reducing their number as well. The expression of inducible nitric oxide synthase (iNOS) was more potentially suppressed by viscosine compared to the FDA approved positive control silymarin. The results of this study indicate that viscosine could be effective in protecting the liver from acute CCl4-induced injury. The hepatoprotective mechanisms of viscosine may be related to the free radical scavenging and attenuation of oxidative stress, as well as to the inhibition of inflammatory response in the liver. Here, we are proposing a novel mechanism of action of viscosine and suggesting that it may be a safe and better in vivo antioxidant.

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