Displaying publications 21 - 40 of 157 in total

Abstract:
Sort:
  1. Taha M, Ismail NH, Jaafar FM, Aziz AN, Yousuf S
    PMID: 23634042 DOI: 10.1107/S1600536813005692
    In the title compound, C16H16N2O3·H2O, the dihedral angle between the benzene rings is 30.27 (7)°. In the crystal, the components are linked by N-H⋯O, O-H⋯O and C-H⋯O inter-actions into a three-dimensional network.
  2. Faudzi AY, Amal NM, Zainal AO, Lailanor I, Sirajuddin H, Taha MA
    Med J Malaysia, 2011 Mar;66(1):32-5.
    PMID: 23765140 MyJurnal
    A systematic approach to death registration and reporting is essential for studies and comparison within or between countries. One of the accepted methods in the system is to have medically certified death. The objective of this study was to improve the proportion of medically certified death (MCD) in the state of Malacca. Structured questionnaires were used by Medical Assistants (MAs) in the investigation of the cause of death for non-medically certified deaths. Data on certification of death by MAs in Malacca was analysed and compared with the total deaths obtained from the Department of Statistics. Possible determinants of deaths were investigated. Total deaths in the state of Malacca during the study period from 2000 - 2001 were 5941. About 35% (883/2493) of the total deaths in year 2000 and 45% (1550/3448) in 2001 certified by MAs were examined. By districts, 50.6% were certified in the district of Malacca Tengah, 13.4% Jasin and 36.0% Alor Gajah in 2000; 65.9% occurred in Malacca Tengah, 11.0% Jasin and 23.2% Alor Gajah in 2001. This project helped to increase the percentage of the medically certified deaths in Malacca from 49.8% in year 1998, 49% in 1999 to 73% in 2000 and 85% in 2001. The proportion of MCD in Malacca in 2000 (73%) may be increased to 93% if all MCDs done by MAs were accepted by the Department of Statistics. There is still a high proportion (23.6%) of ill-defined conditions such as old age and sudden death being diagnosed by MAs. The study shows that the quality of mortality data particularly in the percentage of medically certified deaths can be improved.
  3. Rampal S, Rampal L, Rahmat R, Zain AM, Yap YG, Mohamed M, et al.
    Asia Pac J Public Health, 2010 Apr;22(2):194-202.
    PMID: 19443875 DOI: 10.1177/1010539509334816
    The purpose of this study was to determine the association between different ethnic groups and the prevalence, awareness, and control of diabetes in Malaysia. A population-based cross-sectional study using multistage sampling was conducted in Malaysia. Diabetes is defined as having a fasting blood glucose > or =7 mmol/L or a self-reported diabetic on treatment. Among the 7683 respondents aged > or =30 years, the prevalence of diabetes mellitus was 15.2% (95% CI = 14.1, 16.4). Multivariate analysis showed that compared with Malays, Chinese had lower odds (adjusted odds ratio [aOR] 0.71; 95% CI = 0.56, 0.91) and Indians had higher odds of having diabetes (aOR 1.54; 95% CI = 1.20, 1.98). The odds of diabetes increased with age, family history of diabetes, body mass index, and lower education levels. Among those with diabetes mellitus, 45.0% were aware and 42.7% were under treatment. Among treated diabetics, 25.1% had their fasting blood sugar under control. There is a significant association between prevalence of diabetes and different ethnic groups.
  4. Taha M, Baharudin MS, Ismail NH, Shah SA, Yousuf S
    PMID: 23424550 DOI: 10.1107/S1600536813001748
    In the title hydrazone derivative, C(15)H(14)N(2)O(5), the benzene rings are twisted by 7.55 (8)° with respect to each other. The azomethine double bond adopts an E conformation. The mol-ecular structure is stabilized by intra-molecular O-H⋯N and N-H⋯O hydrogen bonds, generating S6 ring motifs. In the crystal, mol-ecules are linked into a three-dimensional network by O-H⋯O hydrogen bonds.
  5. Baharudin MS, Taha M, Ismail NH, Shah SA, Yousuf S
    PMID: 23424549 DOI: 10.1107/S160053681300175X
    In the title hydrazone derivative, C(15)H(13)ClN(2)O(2), the dihedral angle between the benzene rings is 2.36 (2)°. An intra-molecular N-H⋯O hydrogen bond is present. In the crystal, N-H⋯O and C-H⋯O hydrogen bonds link the mol-ecules into chains running parallel to the b axis.
  6. Taha M, Ismail NH, Jaafar FM, Khan KM, Yousuf S
    PMID: 23476582 DOI: 10.1107/S1600536813004388
    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.
  7. Taha M, Baharudin MS, Ismail NH, Shah SA, Yousuf S
    Acta Crystallogr Sect E Struct Rep Online, 2012 Dec 1;68(Pt 12):o3256.
    PMID: 23468775 DOI: 10.1107/S1600536812042390
    The title compound, C15H14N2O4 adopts an E conformation about the azomethine double bond. Intra-molecular N-H⋯O and O-H⋯N hydrogen bonds generate S(6) rings and help to establish the molecular conformation. The dihedral angle between the benzene rings is 17.84 (10)°. In the crystal, mol-ecules are linked by O-H⋯O and C-H⋯O hydrogen bonds into a two-dimensional network with a herring-bone pattern arranged parallel to the bc plane.
  8. Baharudin MS, Taha M, Ismail NH, Shah SA, Yousuf S
    Acta Crystallogr Sect E Struct Rep Online, 2012 Dec 1;68(Pt 12):o3255.
    PMID: 23468774 DOI: 10.1107/S1600536812042389
    The mol-ecule of the title compound, C16H16N2O4, adopts an E conformation about the azomethine C=N double bond. The dihedral angle formed by the benzene rings is 18.88 (9)°. The mol-ecular conformation is stabilized by an intra-molecular O-H⋯N hydrogen bond, which forms an S(6) ring. In the crystal, the mol-ecules are linked into chains parallel to [001] by N-H⋯O hydrogen bonds. The chains are further connected into a three-dimensional network by π-π stacking inter-actions with centroid-centroid distances of 3.6538 (10) and 3.8995 (11) Å.
  9. Taha M, Ismail NH, Aziza AN, Shah SA, Yousuf S
    PMID: 23424524 DOI: 10.1107/S160053681300127X
    In the title compound, C(29)H(21)O(3)P, a coumarin-substitued ylid, the P atom is linked to three benzene rings and a planar coumarin moiety via a methyl-enecarbonyl group. The bond lengths in the P=C-C=O fragment clearly indicate a delocalized system involving the olefinic and carbonyl bonds. The mol-ecular structure is stabilized by an intra-molecular C-H⋯O inter-action that results in an S7 graph-set ring motif. In the crystal, mol-ecules are linked into a three-dimensional framework by C-H⋯O hydrogen bonds.
  10. 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.
  11. Imran S, Taha M, Ismail NH, Kashif SM, Rahim F, Jamil W, et al.
    Chem Biol Drug Des, 2016 Mar;87(3):361-73.
    PMID: 26362113 DOI: 10.1111/cbdd.12666
    We report herein the synthesis, α-glucosidase inhibition and docking studies for a series of 3-15 new flavones. A simple nucleophilic substitution reaction takes place between 3'hydroxyflavone (2) with halides to afford the new flavones. Chalcone (1), 3'hydroxyflavone (2) and the newly synthesized flavones (3-15) were being evaluated for their ability to inhibit activity of α-glucosidase. Compounds 2, 3, 5, 7-10 and 13 showed good inhibitory activity with IC50 values ranging between 1.26 and 36.44 μm as compared to acarbose (IC50 = 38.25 ± 0.12 μm). Compounds 5 (5.45 ± 0.08 μm), 7 (1.26 ± 0.01 μm) and 8 (8.66 ± 0.08 μm) showed excellent inhibitory activity, and this may be due to trifluoromethyl substitution that is common for these compounds. Compound 7, a 2,5-trifluoromethyl-substituted compound, recorded the highest inhibition activity, and it is thirty times better than the standard drug. Docking studies for compound 7 suggest that both trifluoromethyl substituents are well positioned in a binding pocket surrounded by Phe300, Phe177, Phe157, Ala278, Asp68, Tyr71 and Asp214. The ability of compound 7 to interact with Tyr71 and Phe177 is extremely significant as they are found to be important for substrates recognition by α-glucosidase.
  12. Taha M, Ismail NH, Imran S, Wadood A, Rahim F, Riaz M
    Bioorg Med Chem, 2015 Nov 15;23(22):7211-8.
    PMID: 26507431 DOI: 10.1016/j.bmc.2015.10.017
    Disulfide analogs (1-20) have been synthesized, characterized by HR-MS, (1)H NMR and (13)C NMR and screened for urease inhibitory potential. All compounds were found to have varied degree of urease inhibitory potential ranging in between 0.4 ± 0.01 and 18.60 ± 1.24 μM when compared with standard inhibitor thiourea with IC50 19.46 ± 1.20 μM. Structure activity relationship has been established. The binding interactions of compounds with enzyme were confirmed through molecular docking. All the synthesized compounds 1-20 are new. Our compounds are cheaply synthesizable with high yield and can further be studied to discovery lead compounds. We further, tested for carbonic anhydrase, PDE1 and butyrylcholinesterase but they show no activity. On the other hand we evaluated all compounds for cytotoxicity they showed no toxicity.
  13. Zawawi NK, Taha M, Ahmat N, Ismail NH, Wadood A, Rahim F, et al.
    Bioorg Chem, 2015 Dec;63:36-44.
    PMID: 26432614 DOI: 10.1016/j.bioorg.2015.09.004
    Biscoumarin analogs 1-18 have been synthesized, characterized by EI-MS and (1)H NMR and evaluated for α-glucosidase inhibitory potential. All compounds showed variety of α-glucosidase inhibitory potential ranging in between 13.5±0.39 and 104.62±0.3μM when compared with standard acarbose having IC50 value 774.5±1.94μM. The binding interactions of the most active analogs were confirmed through molecular docking. The compounds showed very good interactions with enzyme. All synthesized compounds 1-18 are new. Our synthesized compounds can further be studied to developed lead compounds.
  14. Taha M, Ismail NH, Imran S, Selvaraj M, Rahim A, Ali M, et al.
    Bioorg Med Chem, 2015 Dec 1;23(23):7394-404.
    PMID: 26526743 DOI: 10.1016/j.bmc.2015.10.037
    A series of compounds consisting of 25 novel oxadiazole-benzohydrazone hybrids (6-30) were synthesized through a five-step reaction sequence and evaluated for their β-glucuronidase inhibitory potential. The IC50 values of compounds 6-30 were found to be in the range of 7.14-44.16μM. Compounds 6, 7, 8, 9, 11, 13, 18, and 25 were found to be more potent than d-saccharic acid 1,4-lactone (48.4±1.25μM). These compounds were further subjected for molecular docking studies to confirm the binding mode towards human β-d-glucuronidase active site. Docking study for compound 13 (IC50=7.14±0.30μM) revealed that it adopts a binding mode that fits within the entire pocket of the binding site of β-d-glucuronidase. Compound 13 has the maximum number of hydrogens bonded to the residues of the active site as compared to the other compounds, that is, the ortho-hydroxyl group forms hydrogen bond with carboxyl side chain of Asp207 (2.1Å) and with hydroxyl group of Tyr508 (2.6Å). The other hydroxyl group forms hydrogen bond with His385 side chain (2.8Å), side chain carboxyl oxygen of Glu540 (2.2Å) and Asn450 side-chain's carboxamide NH (2.1Å).
  15. 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.
  16. Salar U, Taha M, Ismail NH, Khan KM, Imran S, Perveen S, et al.
    Bioorg Med Chem, 2016 Apr 15;24(8):1909-18.
    PMID: 26994638 DOI: 10.1016/j.bmc.2016.03.020
    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.
  17. Taha M, Ismail NH, Imran S, Wadood A, Rahim F, Saad SM, et al.
    Bioorg Chem, 2016 Jun;66:117-23.
    PMID: 27149363 DOI: 10.1016/j.bioorg.2016.04.006
    Twenty derivatives of 5-aryl-2-(6'-nitrobenzofuran-2'-yl)-1,3,4-oxadiazoles (1-20) were synthesized and evaluated for their α-glucosidase inhibitory activities. Compounds containing hydroxyl and halogens (1-6, and 8-18) were found to be five to seventy folds more active with IC50 values in the range of 12.75±0.10-162.05±1.65μM, in comparison with the standard drug, acarbose (IC50=856.45±5.60μM). Current study explores the α-glucosidase inhibition of a hybrid class of compounds of oxadiazole and benzofurans. These findings may invite researchers to work in the area of treatment of hyperglycemia. Docking studies showed that most compounds are interacting with important amino acids Glu 276, Asp 214 and Phe 177 through hydrogen bonds and arene-arene interaction.
  18. Rashid U, Rahim F, Taha M, Arshad M, Ullah H, Mahmood T, et al.
    Bioorg Chem, 2016 Jun;66:111-6.
    PMID: 27140727 DOI: 10.1016/j.bioorg.2016.04.005
    Sixteen 4-hydroxycoumarin derivatives were synthesized, characterized through EI-MS and (1)H NMR and screened for urease inhibitory potential. Three compounds exhibited better urease inhibition than the standard inhibitor thiourea (IC50=21±0.11μM) while other four compounds exhibited good to moderate inhibition with IC50 values between 29.45±1.1μM and 69.53±0.9μM. Structure activity relationship was established on the basis of molecular docking studies, which helped to predict the binding interactions of the most active compounds.
  19. Taha M, Sultan S, Nuzar HA, Rahim F, Imran S, Ismail NH, et al.
    Bioorg Med Chem, 2016 08 15;24(16):3696-704.
    PMID: 27312423 DOI: 10.1016/j.bmc.2016.06.008
    Thirty N-arylidenequinoline-3-carbohydrazides (1-30) have been synthesized and evaluated against β-glucuronidase inhibitory potential. Twenty four analogs showed outstanding β-glucuronidase activity having IC50 values ranging between 2.11±0.05 and 46.14±0.95 than standard d-saccharic acid 1,4 lactone (IC50=48.4±1.25μM). Six analogs showed good β-glucuronidase activity having IC50 values ranging between 49.38±0.90 and 80.10±1.80. Structure activity relationship and the interaction of the active compounds and enzyme active site with the help of docking studies were established. Our study identifies novel series of potent β-glucuronidase inhibitors for further investigation.
  20. Imran S, Taha M, Ismail NH, Fayyaz S, Khan KM, Choudhary MI
    Bioorg Chem, 2015 Oct;62:83-93.
    PMID: 26275866 DOI: 10.1016/j.bioorg.2015.08.001
    This article describes discovery of 29 novel bisindolylmethanes consisting of thiourea moiety, which had been synthesized through three steps. These novel bisindolylmethane derivatives evaluated for their potential inhibitory activity against carbonic anhydrase (CA) II. The results for in vitro assay of carbonic anhydrase II inhibition activity showed that some of the compounds are capable of suppressing the activity of carbonic anhydrase II. Bisindoles having halogen at fifth position showed better inhibitory activity as compared to unsubstituted bisindoles. Derivatives showing inhibition activity docked to further, understand the binding behavior of these compounds with carbonic anhydrase II. Docking studies for the active compound 3j showed that nitro substituent at para position fits into the core of the active site. The nitro substituent of compound 3j is capable of interacting with Zn ion. This interaction believed to be the main factor causing inhibition activity to take place.
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links