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Fulltext (2,4-Dimethoxy-benzyl-idene)-2-hydroxy-benzohydrazide ethanol solvate

Yehye WA, Ariffin A, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008 May 03;64(Pt 6):o961.

PMID: 21202691 DOI: 10.1107/S1600536808011768

In the planar title mol-ecule, C(16)H(16)N(2)O(4)·C(2)H(6)O, the planar Schiff base molecule is linked to the ethanol solvent mol-ecule by a hydr-oxy-amide hydrogen bond. The hydr-oxy group of the ethanol mol-ecule is a hydrogen-bond donor to the double-bonded N atom of an adjacent Sciff base, pairs of interactions taking place across a center of symmetry and giving rise to a hydrogen-bonded dimer.

Fulltext N-Acetyl-2-hydroxy-N'-[methoxy(1-methylindol-2-yl)methyl]benzohydrazide

Yehye WA, Rahman NA, Ariffin A, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008 Aug 23;64(Pt 9):o1824.

PMID: 21201799 DOI: 10.1107/S1600536808026846

In the crystal structure of the title Schiff-base, C(20)H(21)N(3)O(4), the amino group forms an N-H⋯O hydrogen bond to the acetyl group of an adjacent mol-ecule, forming a zigzag chain. The 2-hydr-oxy group is inter-nally hydrogen bonded to the amido group though an O-H⋯O hydrogen bond.

Fulltext Biphenyl-4-carbaldehyde azine

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008;64(Pt 12):o2444.

PMID: 21581412 DOI: 10.1107/S1600536808038622

The complete mol-ecule of the title compound, C(26)H(20)N(2), is generated by crystallographic inversion symmetry. The terminal phenyl ring is twisted by 19.2 (1)° with respect to the adjacent phenyl-ene ring.

Fulltext N'-(3-Bromo-5-chloro-2-hydroxy-benzyl-idine)-2-hydroxy-benzohydrazide

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008;64(Pt 12):o2438.

PMID: 21581406 DOI: 10.1107/S1600536808038634

In the approximately planar title mol-ecule, C(14)H(10)BrClN(3)O(2), the dihedral angle between the aromatic ring planes is 5.79 (12)°. The conformation is stabilized by intra-molecular O-H⋯N and N-H⋯O hydrogen bonds and an inter-molecular O-H⋯O link leads to chains in the crystal propagating in [001].

Fulltext N'-(3,5-Di-tert-butyl-4-hydroxy-benzyl-idene)-2-hydroxy-benzohydrazide methanol solvate

Yehye WA, Ariffin A, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008;64(Pt 8):o1452.

PMID: 21203167 DOI: 10.1107/S1600536808020746

The asymmetric unit of the title compound, C(22)H(28)N(2)O(3)·CH(4)O, consists of two independent Schiff base mol-ecules and two independent methanol solvent mol-ecules. In one Schiff base mol-ecule, the 2-hydr-oxy group forms an intra-molecular hydrogen bond with the amide O atom, whereas in the other Schiff base mol-ecule, the 2-hydr-oxy-substituted benzene ring is oriented so that the 2-hydr-oxy group serves as hydrogen-bond acceptor for the amide NH group. In the crystal structure, Schiff base mol-ecules inter-act with methanol solvent to furnish a hydrogen-bonded chain.

Fulltext 2-(3,5-Di-tert-butyl-4-hydroxy-benzyl-sulfan-yl)nicotinic acid

Mansor S, Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008;64(Pt 9):o1778.

PMID: 21201758 DOI: 10.1107/S1600536808026056

Two mol-ecules of the title compound, C(21)H(27)NO(3)S, are disposed about a center of inversion, generating an O-H⋯O hydrogen-bonded dimer.

Fulltext Di-n-butyl-ammonium 2-(3,5-di-tert-butyl-4-hydroxy-benzyl-sulfan-yl)nicotinate

Mansor S, Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008;64(Pt 9):o1799.

PMID: 21201778 DOI: 10.1107/S1600536808026202

The asymmetric unit of the title compound, C(8)H(20)N(+)·C(21)H(26)NO(3)S(-), contains two indpendent ion pairs which are disposed about a psuedo-inversion center, generating an ammonium-carboxylate N-H⋯O hydrogen-bonded four-component cluster. In the crystal structure, adjacent clusters are linked by hydr-oxy-carboxylate O-H⋯O hydrogen bonds, forming a chain.

Fulltext 2-Hydr-oxy-(2-methyl-1H-indol-3-ylmethyl-idene)benzohydrazide ethanol solvate

Yehye WA, Ariffin A, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008;64(Pt 6):o960.

PMID: 21202690 DOI: 10.1107/S1600536808011756

In the title compound, C(17)H(15)N(3)O(2)·C(2)H(6)O, Schiff base molecules are linked by a hydr-oxy-amido hydrogen bond into a helical chain running along the b axis. This chain is consolidated by two other hydrogen bonds; the ethanol solvent mol-ecule is a hydrogen-bond donor to the amide group and a hydrogen-bond acceptor for the indolyl NH group of an adjacent Schiff base mol-ecule.

Fulltext Dipyridinium 2,2'-dithio-dinicotinate

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2009;65(Pt 5):o1068.

PMID: 21583884 DOI: 10.1107/S1600536809013543

The dianion of the title salt, 2C(5)H(6)N(+)·C(12)H(6)N(2)O(4)S(2) (2-), lies on a special position of 2 site symmetry that relates one thio-nicotinate part to the other, and the dihedral angle between the niotinate planes is 89.2 (2)°. The pyridinium cations are hydrogen bonded to the carboxyl-ate group by way of N-H⋯O links.

Fulltext 2-[(3,5-Di-tert-butyl-4-hydroxy-benz-yl)-sulfan-yl]-N'-isopropyl-ideneaceto-hydrazide

Yehye WA, Ariffin A, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2009;65(Pt 4):o730.

PMID: 21582464 DOI: 10.1107/S1600536809007843

The title compound, C(20)H(32)N(2)O(2)S, the condensation product of a thio-acetohydrazine and acetone, has a two-coordinate S atom and the angle at this atom is 100.7 (1)°. The (CH(3))C=N-NH-C(O)- substituent engages in N-H⋯O hydrogen-bonding inter-actions with the substituent of an adjacent mol-ecule across a center of inversion, generating a dimeric structure.

Fulltext 2-(3,5-Di-tert-butyl-4-hydroxy-benzyl-sulfan-yl)-N'-(3-methoxy-benzyl-idene)acetohydrazide

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2009;65(Pt 9):o2112.

PMID: 21577527 DOI: 10.1107/S1600536809030645

The title compound, C(25)H(34)N(2)O(3)S, is a derivative of N'-benzyl-ideneacetohydrazide having substituents on the acetyl and benzylidenyl parts, and displays a planar C(carbon-yl)-NH-NC(anis-yl) fragment [torsion angle = 174.9 (3)°]. The -NH- unit forms an N-H⋯O hydrogen bond with the carbonyl O atom of an inversion-related mol-ecule.

Fulltext 2-[4-Acetyl-5-(biphenyl-4-yl)-4,5-dihydro-1,3,4-oxadiazol-2-yl]phenyl acetate

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2010 Mar 20;66(Pt 4):o878.

PMID: 21580697 DOI: 10.1107/S1600536810009621

In the title mol-ecule, C(24)H(20)N(2)O(4), the five-membered oxadiazole ring is nearly planar (r.m.s. deviation = 0.053 Å) and the phenyl ring of the biphenyl unit attached to it forms a dihedral angle of 73.2 (1)°; the other phenyl ring is close to coplanar with the oxadiazole ring [dihedral angle = 6.2 (2)°].

Fulltext 2-Sulfanyl-idene-1,2-dihydro-pyridine-3-carbohydrazide

Mansor S, Yehye WA, Ariffin A, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2010;66(Pt 10):o2516.

PMID: 21587510 DOI: 10.1107/S160053681003521X

All non-H atoms of the title compound, C(6)H(7)N(3)OS, which exists in the thione form, lie in a common plane (r.m.s. of non-H atoms = 0.08 Å). The amino group of the -NH-NH(2) substituent forms an intra-molecular hydrogen bond to the S atom. The terminal -NH(2) group is pyramidally coordinated; it forms a weak N-H⋯O and a weak N-H⋯S hydrogen bond. Furthermore, the N atom is an acceptor for a C-H⋯N contact. The amino group of the ring is a hydrogen-bond donor to the carbonyl O atom of an adjacent mol-ecule, this inter-action giving rise to a linear chain motif running along the b axis.

Fulltext N'-[(Biphenyl-4-yl)methyl-ene]-2-[(3,5-di-tert-butyl-4-hydroxy-benz-yl)sulfan-yl]acetohydrazide

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2010;66(Pt 4):o734.

PMID: 21580580 DOI: 10.1107/S1600536810006884

In the title compound, C(30)H(36)N(2)O(2)S, the dihedral angle between the two aromatic rings of the biphenyl residue is 31.2 (1)°. The two methyl-ene C atoms subtend an angle of 99.9 (1)° at the S atom. In the crystal, mol-ecules form inversion dimers linked by pairs of N-H⋯O hydrogen bonds. The hydroxyl group is shielded by the tert-butyl residues and is therefore not involved in any hydrogen bonding.

Antioxidant, cytotoxic activities, and structure-activity relationship of gallic acid-based indole derivatives

Khaledi H, Alhadi AA, Yehye WA, Ali HM, Abdulla MA, Hassandarvish P

Arch Pharm (Weinheim), 2011 Nov;344(11):703-9.

PMID: 21953995 DOI: 10.1002/ardp.201000223

A new series of gallic hydrazones containing an indole moiety was synthesized through the reaction of gallic hydrazide and different indole carboxaldehydes. Their antioxidant activities were determined on DPPH radical scavenging and inhibition of lipid peroxidation. The in-vitro cytotoxic activities of the compounds were evaluated against HCT-116 (human colon cancer cell line) and MCF-7 (estrogen-dependent human breast cancer cell line) by the MTT method. An attempt to correlate the biological results with their structural characteristics has been done. A limited positive structure activity relationship was found between cytotoxic and antioxidant activities.

Fulltext Synthesis, characterization, X-ray crystallography, acetyl cholinesterase inhibition and antioxidant activities of some novel ketone derivatives of gallic hydrazide-derived Schiff bases

Gwaram NS, Ali HM, Abdulla MA, Buckle MJ, Sukumaran SD, Chung LY, et al.

Molecules, 2012 Feb 28;17(3):2408-27.

PMID: 22374313 DOI: 10.3390/molecules17032408

Alzheimer's disease (AD) is the most common form of dementia among older people and the pathogenesis of this disease is associated with oxidative stress. Acetylcholinesterase inhibitors with antioxidant activities are considered potential treatments for AD. Some novel ketone derivatives of gallic hydrazide-derived Schiff bases were synthesized and examined for their antioxidant activities and in vitro and in silico acetyl cholinesterase inhibition. The compounds were characterized using spectroscopy and X-ray crystallography. The ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays revealed that all the compounds have strong antioxidant activities. N-(1-(5-bromo-2-hydroxyphenyl)-ethylidene)-3,4,5-trihydroxybenzohydrazide (2) was the most potent inhibitor of human acetyl cholinesterase, giving an inhibition rate of 77% at 100 μM. Molecular docking simulation of the ligand-enzyme complex suggested that the ligand may be positioned in the enzyme's active-site gorge, interacting with residues in the peripheral anionic subsite (PAS) and acyl binding pocket (ABP). The current work warrants further preclinical studies to assess the potential for these novel compounds for the treatment of AD.

Fulltext Butylated hydroxytoluene analogs: synthesis and evaluation of their multipotent antioxidant activities

Yehye WA, Abdul Rahman N, Alhadi AA, Khaledi H, Weng NS, Ariffin A

Molecules, 2012 Jun 25;17(7):7645-65.

PMID: 22732881 DOI: 10.3390/molecules17077645

A computer-aided predictions of antioxidant activities were performed with the Prediction Activity Spectra of Substances (PASS) program. Antioxidant activity of compounds 1, 3, 4 and 5 were studied using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and lipid peroxidation assays to verify the predictions obtained by the PASS program. Compounds 3 and 5 showed more inhibition of DPPH stable free radical at 10⁻⁴ M than the well-known standard antioxidant, butylated hydroxytoluene (BHT). Compound 5 exhibited promising in vitro inhibition of Fe²⁺-induced lipid peroxidation of the essential egg yolk as a lipid-rich medium (83.99%, IC₅₀ 16.07 ± 3.51 μM/mL) compared to α-tocopherol (α-TOH, 84.6%, IC₅₀ 5.6 ± 1.09 μM/mL). The parameters for drug-likeness of these BHT analogues were also evaluated according to the Lipinski’s “rule-of-five” (RO5). All the BHT analogues were found to violate one of the Lipinski’s parameters (LogP > 5), even though they have been found to be soluble in protic solvents. The predictive polar surface area (PSA) and absorption percent (% ABS) data allow us to conclude that they could have a good capacity for penetrating cell membranes. Therefore, one can propose these new multipotent antioxidants (MPAOs) as potential antioxidants for tackling oxidative stress and lipid peroxidation processes.

Fulltext Effect of oral administration of ethanolic extract of Vitex negundo on thioacetamide-induced nephrotoxicity in rats

Kadir FA, Kassim NM, Abdulla MA, Yehye WA

BMC Complement Altern Med, 2013 Oct 30;13:294.

PMID: 24499255 DOI: 10.1186/1472-6882-13-294

BACKGROUND: Oxidative stress due to abnormal induction of reactive oxygen species (ROS) molecules is believed to be involved in the etiology of many diseases. Evidences suggest that ROS is involved in nephrotoxicity through frequent exposure to industrial toxic agents such as thioacetamide (TAA). The current investigation was designed to explore the possible protective effects of the leaves of Vitex negundo(VN) extract against TAA-induced nephrotoxicity in rats.

METHODS: Twenty four Sprague Dawleyrats were divided into four groups: (A) Normal control, (B) TAA (0.03% w/v in drinking water), (C) VN100 (VN 100 mg/kg + TAA) and (D) VN300 (VN 300 mg/kg + TAA). Blood urea and serum creatinine levels were measured,supraoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) levels of renal tissue were assayed. Histopathological analysis together with the oxidative stress nicotinamide adenine dinucleotide phosphate (NADPH) oxidase p22phox in kidney sections were examined in all experimental groups.

RESULTS: Blood urea and serum creatinine levels were increased in TAA group as a result of the nephrotoxicity compared to the VN100 and VN300 groups where, the levels were significantly decreased (p

Fulltext PASS-predicted Vitex negundo activity: antioxidant and antiproliferative properties on human hepatoma cells--an in vitro study

Kadir FA, Kassim NM, Abdulla MA, Yehye WA

BMC Complement Altern Med, 2013;13:343.

PMID: 24305067 DOI: 10.1186/1472-6882-13-343

Hepatocellular carcinoma is a common type of tumour worldwide with a high mortality rate and with low response to current cytotoxic and chemotherapeutic drugs. The prediction of activity spectra for the substances (PASS) software, which predicted that more than 300 pharmacological effects, biological and biochemical mechanisms based on the structural formula of the substance was efficiently used in this study to reveal new multitalented actions for Vitex negundo (VN) constituents.

Fulltext Hepatoprotective Role of Ethanolic Extract of Vitex negundo in Thioacetamide-Induced Liver Fibrosis in Male Rats

Kadir FA, Kassim NM, Abdulla MA, Yehye WA

Evid Based Complement Alternat Med, 2013;2013:739850.

PMID: 23762157 DOI: 10.1155/2013/739850

The hepatoprotective activity of ethanolic extract from the leaves of Vitex negundo (VN) was conducted against thioacetamide- (TAA-) induced hepatic injury in Sprague Dawley rats. The therapeutic effect of the extract was investigated on adult male rats. Rats were divided into seven groups: control, TAA, Silymarin (SY), and VN high dose and low dose groups. Rats were administered with VN extract at two different doses, 100 mg/kg and 300 mg/kg body weight. After 12 weeks, the rats administered with VN showed a significantly lower liver to body weight ratio. Their abnormal levels of biochemical parameters and liver malondialdehyde were restored closer to the normal levels and were comparable to the levels in animals treated with the standard drug, SY. Gross necropsy and histopathological examination further confirmed the results. Progression of liver fibrosis induced by TAA in rats was intervened by VN extract administration, and these effects were similar to those administered with SY. This is the first report on hepatoprotective effect of VN against TAA-induced liver fibrosis.

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