LC-MS/MS method for the quantitation of decitabine and venetoclax in rat plasma after SPE: Application to pharmacokinetic study.

This study developed a novel, sensitive and selective LC-MS/MS method for the concurrent determination of DCB and VTX in rat plasma using encorafenib as internal standard (IS). To identify DCB, VTX, and IS, the positive multiple reaction monitoring (MRM) mode was used. Chromatographic separation was carried out using a reversed-phase Agilent Eclipse plus C18 column (100 mm × 2.1 mm, 3.5 µm) and an isocratic mobile phase made up of water with 0.1% formic acid and acetonitrile (50:50, v/v, pH 3.2) at a flow rate of 0.30 mL/min for 3.0 min. Prior to analysis, the DCB and VTX with the IS were extracted from plasma using the solid-phase extraction (SPE) method. High recovery rates for DCB, VTX and IS were achieved using the C18 cartridge without interference from plasma endogenous. The developed method was validated as per the FDA guidelines over a linear concentration range in rat plasma from 5-3000 and 5-1000 ng/mL for DCB and VTX, respectively with r2 ≥ 0.998. For both drugs, the lower limits of detection (LLOD) were 2.0 ng/mL. After the HLOQ sample was injected, less than 20% of the LLOQ of DCB, VTX, and less than 5% of the IS carry-over in the blank sample was attained. The overall recoveries of DCB and VTX from rat plasma were in the range of 90.68-97.56%, and the mean RSD of accuracy and precision results was ≤6.84%. For the first time, the newly developed approach was effectively used in a pharmacokinetic study on the simultaneous oral administration of DCB and VTX in rats that received 15.0 mg/kg of DCB and 100.0 mg/kg of VTX.

Synthesis, potential antitumor activity, cell cycle analysis, and multitarget mechanisms of novel hydrazones incorporating a 4-methylsulfonylbenzene scaffold: a molecular docking study.

Hydrazone is a bioactive pharmacophore that can be used to design antitumor agents. We synthesised a series of hydrazones (compounds 4-24) incorporating a 4-methylsulfonylbenzene scaffold and analysed their potential antitumor activity. Compounds 6, 9, 16, and 20 had the most antitumor activity with a positive cytotoxic effect (PCE) of 52/59, 27/59, 59/59, and 59/59, respectively, while compounds 5, 10, 14, 15, 18, and 19 had a moderate antitumor activity with a PCE of 11/59-14/59. Compound 20 was the most active and had a mean 50% cell growth inhibition (GI50) of 0.26 µM. Compounds 9 and 20 showed the highest inhibitory activity against COX-2, with a half-maximal inhibitory concentration (IC50) of 2.97 and 6.94 µM, respectively. Compounds 16 and 20 significantly inhibited EGFR (IC50 = 0.2 and 0.19 µM, respectively) and HER2 (IC50 = 0.13 and 0.07 µM, respectively). Molecular docking studies of derivatives 9, 16, and 20 into the binding sites of COX-2, EGFR, and HER2 were carried out to explore the interaction mode and the structural requirements for antitumor activity.

PDCD6IP, encoding a regulator of the ESCRT complex, is mutated in microcephaly.

Primary microcephaly (PM) is a highly heterogeneous neurodevelopmental disorder with many contributing risk genes and loci identified to date. We report a consanguineous family with PM, intellectual disability and short stature. Using whole exome sequencing, we identified a homozygous frameshift variant in programmed cell death 6 interacting protein (PDCD6IP, c.154_158dup; p.Val54Profs*18). This gene, PDCD6IP, plays an important role in the endosomal sorting complexes required for transport (ESCRT) pathway in the abscission stage of cytokinesis and apoptosis, and is required for normal brain development in mice. The clinical features observed in our patient were similar to the phenotypes observed in mouse and zebrafish models of PDCD6IP mutations in previous studies. This study provides evidence that clinical manifestations of PDCD6IP mutations as seen in our patients with PM and ID may be a novel cause for neurodevelopmental disorders.

Evaluation of long-term effectiveness of the use of carglumic acid in patients with propionic acidemia (PA) or methylmalonic acidemia (MMA): study protocol for a randomized controlled trial.

INTRODUCTION: Propionic acidemia (PA) and methylmalonic acidemia (MMA) are rare autosomal recessive inborn errors of metabolism characterized by hyperammonemia due to N-acetylglutamate synthase (NAGS) dysfunction. Carglumic acid (Carbaglu®; Orphan Europe Ltd.) is approved by the US Food and Drug Administration (USFDA) for the treatment of hyperammonemia due hepatic NAGS deficiency. Here we report the rationale and design of a phase IIIb trial that is aimed at determining the long-term efficacy and safety of carglumic acid in the management of PA and MMA. METHODS: This prospective, multicenter, open-label, randomized, parallel group phase IIIb study will be conducted in Saudi Arabia. Patients with PA or MMA (≤15 years of age) will be randomized 1:1 to receive twice daily carglumic acid (50 mg/kg/day) plus standard therapy (protein-restricted diet, L-carnitine, and metronidazole) or standard therapy alone for a 2-year treatment period. The primary efficacy outcome is the number of emergency room visits due to hyperammonemia. Safety will be assessed throughout the study and during the 1 month follow-up period after the study. DISCUSSION: Current guidelines recommend conservative medical treatment as the main strategy for the management of PA and MMA. Although retrospective studies have suggested that long-term carglumic acid may be beneficial in the management of PA and MMA, current literature lacks evidence for this indication. This clinical trial will determine the long-term safety and efficacy of carglumic acid in the management of PA and MMA. TRIAL REGISTRATION: King Abdullah International Medical Research Center ( KAIMRC ): (RC13/116) 09/1/2014. Saudi Food and Drug Authority (SFDA) (33066) 08/14/2014. ClinicalTrials.gov (identifier: NCT02426775) 04/22/2015.

Synthesis and anti-inflammatory activity of diversified heterocyclic systems.

In continuation with our research program on the development of novel bioactive molecules, we report herein the design and synthesis of a series of diversified heterocycles (4-22). The synthesized compounds were evaluated for their anti-inflammatory activity. The chemical structures of the newly synthesized compounds have been confirmed by NMR, FTIR, and microanalysis.

Adenosine Kinase Deficiency: Report and Review.

Adenosine kinase (ADK) deficiency (OMIM [online mendelian inheritance in man]: 614300) is an autosomal recessive disorder of adenosine and methionine metabolism, with a unique clinical phenotype, mainly involving the central nervous system and dysmorphic features. Patients usually present early in life with sepsis-like symptoms, respiratory difficulties, and neonatal jaundice. Subsequently, patients demonstrate hypotonia and global developmental delay. Biochemically, methionine is elevated with normal homocysteine levels and the diagnosis is confirmed through molecular analysis of the ADK gene. There is no curative treatment; however, a methionine-restricted diet has been tried with variable outcomes. Herein, we report a 4-year-old Saudi female with global developmental delay, hypotonia, and dysmorphic features. Interestingly, she has a tall stature, developmental dysplasia of the hip, optic nerve gliosis, and tigroid fundus. We found a mutation not reported previously and we compared the current case with previously reported cases. We alert clinicians to consider ADK deficiency in any neonate presenting with global developmental delay, hypotonia, dysmorphic features, and high methionine levels.

Synthesis, Antiviral, and Antimicrobial Evaluation of Benzyl Protected Diversified C-nucleosides.

Formyl glycals are the versatile synthetic intermediates and can serves as precursor for the synthesis of various C and N-nucleosides. Due to the presence of electron donating and electron withdrawing character on formyl sugars which makes the molecule more susceptible to nucleophilic attack. Utilizing same strategy, we propose the synthesis of diversified C-nucleosides (3-14) by reaction with N,N dinucleophiles. These nucleoside analogs were than tested against viral, bacterial and fungal strains.

Clinical, Biochemical, and Molecular Features in 37 Saudi Patients with Very Long Chain Acyl CoA Dehydrogenase Deficiency.

BACKGROUND: Very long chain acyl CoA dehydrogenase (VLCAD) deficiency (OMIM#201475) is an autosomal recessive disorder of fatty acid beta oxidation caused by defect in the ACADVL. The aim of this study was to analyze the clinical, biochemical, and molecular features of VLCAD deficiency in Saudi Arabia, including the treatment and outcome. METHODS: We carried out a retrospective chart review analysis of 37 VLCAD deficiency patients from two tertiary centers in Saudi Arabia, over a 14-year period (2002-2016). Twenty-three patients were managed at King Abdul-Aziz Medical City and fourteen patients at King Fahad Medical City. RESULTS: Severe early onset VLCAD deficiency is the most frequent phenotype in our patients, caused by four different mutations in ACADVL; 31 patients (83.7%) had a homozygous nonsense mutation in exon 2 of ACADVL c.65C>A;p. Ser22X. Twenty-three patients died before the age of 2 years, despite early detection by newborn screening and implementation of treatment, including supplementation with medium chain triglycerides. CONCLUSION: This study reports the clinical, biochemical, molecular findings, treatment, and outcome of patients with VLCAD deficiency over the last 14 years. We identified the most common variant and one new variant in ACADVL. Despite early diagnosis and treatment, the outcome of VLCAD deficiency in this Saudi Arabian population remains poor. Preventive measures, such as prenatal diagnosis, could be implemented.

Synthesis, anticancer and apoptosis-inducing activities of quinazoline-isatin conjugates: epidermal growth factor receptor-tyrosine kinase assay and molecular docking studies.

A new series of quinazolinone compounds 16-34 incorporating isatin moieties was synthesized. The antitumor efficacy of the compounds against MDA-MB-231, a breast cancer cell line, and LOVO, a colon cancer cell line, was assessed. Compounds 20, 21, 22, 23, 25, 27, 28, 29, 30, 31, 32, 33, and 34 displayed potent antitumor activity against MDA-MB-231 and LOVO cells (IC50: 10.38-38.67 µM and 9.91-15.77 µM, respectively); the comparative IC50 values for 5-fluorouracil and erlotinib in these cells lines were 70.28 µM, 22.24 µM and 15.23 µM, 25.31 µM respectively. The EGFR-TK assay and induction of apoptosis for compound 31 were investigated to assess its potential cytotoxic activity as a representative example of the novel synthesized compounds. At a concentration of 10 µM, compound 31 exhibited efficient inhibitory effect against EGFR-TK and induced apoptosis in MDA-MB-231 cells. Furthermore, a molecular docking study for compound 31 and erlotinib was performed to verify the binding mode toward the EGFR kinase enzyme, and showed a similar interaction as that with erlotinib alone. Graphical Abstract: Compound 31 showed potent antitumor activity and efficient inhibitory effect against EGFR-TK and induced apoptosis of MDA-MB-231 cells at a concentration of 10 µM.

Early onset of Fazio-Londe syndrome: the first case report from the Arabian Peninsula.

Fazio-Londe syndrome is a rare neurological disorder presenting with sensorineural deafness, bulbar palsy and respiratory compromise that is caused by mutation in the SLC52A3 gene, which encodes the intestinal (hRFT2) riboflavin transporter. We report a patient with early onset of Fazio-Londe syndrome as the first case report in Saudi Arabia with rapid regression to death at 24 months of age.

Delineation of cystinuria in Saudi Arabia: A case series.

BACKGROUND: Cystinuria is an inherited metabolic disease that is caused by defects in two genes, SLC3A1 and SLC7A9, which result in a renal reabsorptive defect of cystine and other dibasic amino acids, including ornithine, arginine, and lysine. Patients usually present with recurrent renal calculi and may develop renal impairment. Medical management includes high fluid intake and chelating agents. To the best of our knowledge, this is the first study describing cystinuria in Saudi Arabia. METHODS: A retrospective chart review for cystinuria patients from the genetic and nephrology divisions between 2010 to 2015. All patients were investigated, diagnosed and treated at King Abdulaziz Medical City in Saudi Arabia. RESULTS: Eight patients were identified from five unrelated families. The age of onset ranged from birth to 14 years. The female to male ratio was 1.7:1. Two new variants in the SLC3A1 and SLC9A7 genes were discovered. All of the detected mutations were missense variants in three different exons, such as c.1711 T > A (p.Cys571Ser) (exon 10), c.1166C > T p.Thr389Met (exon 11) and c.1400 T > A p.Met467Lys (exon 8). Additionally, 37.5% of our patients developed arterial hypertension and 25% had urinary tract infection, but none had renal impairment. No significant clinical differences were detected in this study between type A (SLC3A1 variants) and type B cystinuria (SLC7A9 variant). Two cases were diagnosed based on clinical information, biochemical testing and a positive family history as all of the molecular testing for cystinuria was negative. CONCLUSION: Cystinuria has wide genetic heterogeneity with a poor genotype/phenotype correlation. Negative molecular investigations should not rule out the disease if clinical and biochemical investigations support the diagnosis. A larger data registry is essential to better describe the cystinuria genotype/phenotype in Saudi Arabia.

Synthesis, anti-inflammatory, analgesic and COX-1/2 inhibition activities of anilides based on 5,5-diphenylimidazolidine-2,4-dione scaffold: Molecular docking studies.

The design, synthesis and pharmacological activities of a group of 5,5-diphenylimidazolidine-2,4-dione bearing anilide, phenacyl and benzylidene fragments 2-27 were reported. The prepared 5,5-diphenylimidazolidine-2,4-dione derivatives were evaluated in vivo for anti-inflammatory, analgesic activities and in vitro for COX-1/2 inhibition assay. Among the tested compounds, derivatives 5, 9, 10, 13, and 14 showed significant and potent anti-inflammatory and analgesic activities almost equivalent to reference drug celecoxib. In COX-1/2 inhibition assay, compounds 5, 9, 10 and 14 showed high COX-2 inhibitory activity (IC50 = 0.70 µM, 0.44 µM, 0.61 µM and 0.41 µM; respectively) and selectivity index (SI) range of 142-243 comparable to celecoxib [COX-2 (SI) > 333]. These potent COX-2 inhibitors 9, 10, 13, and 14 were docked into the active site pocket of COX-2 to explore the binding mode and possible interactions of these ligands.

Synthesis, antitumor and antimicrobial activity of some new 6-methyl-3-phenyl-4(3H)-quinazolinone analogues: in silico studies.

Some new derivatives of substituted-4(3H)-quinazolinones were synthesized and evaluated for their in vitro antitumor and antimicrobial activities. The results of this study demonstrated that compound 5 yielded selective activities toward NSC Lung Cancer EKVX cell line, Colon Cancer HCT-15 cell line and Breast Cancer MDA-MB-231/ATCC cell line, while NSC Lung Cancer EKVX cell line and CNS Cancer SF-295 cell line were sensitive to compound 8. Additionally, compounds 12 and 13 showed moderate effectiveness toward numerous cell lines belonging to different tumor subpanels. On the other hand, the results of antimicrobial screening revealed that compounds 1, 9 and 14 are the most active against Staphylococcus aureus ATCC 29213 with minimum inhibitory concentration (MIC) of 16, 32 and 32 µg/mL respectively, while compound 14 possessed antimicrobial activities against all tested strains with the lowest MIC compared with other tested compounds. In silico study, ADME-Tox prediction and molecular docking methodology were used to study the antitumor activity and to identify the structural features required for antitumor activity.

Synthesis, anticonvulsant activity and molecular modeling study of some new hydrazinecarbothioamide, benzenesulfonohydrazide, and phenacylacetohydrazide analogues of 4(3H)-quinazolinone.

A new series of quinazoline analogues was designed and synthesized to get the target compounds 18-21, 30-41, 46-53, and 57-76. The Obtained compounds were evaluated for their anticonvulsant activity using PTZ and picrotoxin convulsive models. Compounds 47, 63, 68 and 73 proved to be the most active compounds in this study with a remarkable 100% protection against PTZ induced convulsions. Compounds 47, 63, 68 and 73 proved to be 10, 4, 4, and 5 fold more active, respectively than the used positive control sodium valproate. Structure activity correlation concluded valuable pharmacophoric information which confirmed by molecular modeling studies. Molecular docking study of 68 suggested its agonistic behavior toward GABAA receptor. The studied quinazoline analogues could be considered as useful templates for future development and further derivatization.

Synthesis and anticancer potential of certain novel 2-oxo-N'-(2-oxoindolin-3-ylidene)-2H-chromene-3-carbohydrazides.

Treatment of ethyl 3-hydrazinyl-3-oxopropanoate (6) with indoline-2,3-dione derivatives 7a-g gave ethyl 3-oxo-3-(2-(2-oxoindolin-3-ylidene)hydrazinyl)propanoates 8a-g which were allowed to react with the appropriate salicyaldehyde 9a and/or 9b to furnish the chromene-based hydrazones 10a-i. Compounds 10a-i displayed a significant activity against HT-29 colon cancer cell line and a moderate activity against leukemia K562 cell line. Compound 10f emerged as the most active congener toward HT-29 colon cancer cell line with IC50 = 7.98 ± 0.05 µM whereas compound 10c exhibited the best antiproliferative activity against leukemia K562 cell line with IC50 = 9.44 ± 0.02 µM. Moreover, compound 1e showed 87.81 ± 7% inhibition of side population (SP) HT-29 colon cancer stem cells.

3-[(4-Phenyl-piperazin-1-yl)meth-yl]-5-(thio-phen-2-yl)-2,3-di-hydro-1,3,4-oxa-diazole-2-thione.

In the title compound, C17H18N4OS2, the 2-thienyl ring is disordered over two co-planar, opposite orientations in a 0.684 (2): 0.316 ratio. The 1,3,4-oxa-diazole ring is almost co-planar with the attached 2-thienyl ring [dihedral angles of 5.34 (19) and 4.8 (5)° for the major and minor components, respectively]. The relative disposition of the thione- and ring-S atoms is anti for the major orientation of the 2-thienyl residue. Overall, the shape of the mol-ecule approximates the letter V. In the crystal, a three-dimensional architecture is consolidated by a combination of weak C-H⋯S and C-H⋯π contacts.

Molecular design, synthesis and biological evaluation of cyclic imides bearing benzenesulfonamide fragment as potential COX-2 inhibitors. Part 2.

A group of cyclic imides (1-10) was designed for evaluation as a selective COX-2 inhibitors and investigated in vivo for their anti-inflammatory activity. Compounds 6a, 6b, 8a, 8b, 9a, 9b, 10a and 10b were proved to be potent COX-2 inhibitors with IC50 range of 0.1-4.0 µM. In vitro COX-1/COX-2 inhibition structure-activity studies identified compound 8a as a highly potent (IC50=0.1 µM), and an extremely selective [COX-2 (SI)>1000] comparable to celecoxib [COX-2 (SI)>384], COX-2 inhibitor that showed superior anti-inflammatory activity (ED50=72.4 mg/kg) relative to diclofenac (ED50=114 mg/kg). Molecular modeling was carried out through docking the designed compounds into the COX-2 binding site to predict if these compounds have analogous binding mode to the COX-2 inhibitors. The study showed that the homosulfonamide fragment of 8a inserted deep inside the 2°-pocket of the COX-2 active site, where the SO2NH2 group underwent H-bonding interaction with Gln(192)(2.95 Å), Phe(518)(2.82 Å) and Arg(513)(2.63 and 2.73 Å). Docking study of the synthesized compound 8a into the active site of COX-2 revealed a similar binding mode to SC-558, a selective COX-2 inhibitor.

Validated enzyme-linked immunosorbent assay for determination of rosuvastatin in plasma at picogram level.

In this study, a highly sensitive enzyme-linked immunosorbent assay (ELISA) has been developed and validated for the determination of rosuvastatin (ROS) in plasma samples at picogram level. The assay employed a polyclonal antibody that specifically recognizes ROS with high affinity, and ROS conjugate of bovine serum albumin (ROS-BSA) immobilized onto microplate wells as a solid phase. The assay involved a competitive binding reaction between ROS, in plasma sample, and the immobilized ROS-BSA for the binding sites on a limited amount of the anti-ROS antibody. The bound anti-ROS antibody was quantified with horseradish peroxidase-labelled second anti-rabbit IgG antibody (HRP-IgG) and 3,3`,5,5`-tetramethylbenzidine (TMB) as a substrate for the peroxidase enzyme. The concentration of ROS in the sample was quantified by its ability to inhibit the binding of the anti-ROS antibody to the immobilized ROS-BSA and subsequently the colour intensity in the assay wells. The assay limit of detection was 25 pg ml(-1) and the effective working range at relative standard deviations (RSD) of ≤ 5% was 40-2000 pg ml(-1). Analytical recovery of ROS from spiked plasma was 96.2 - 104.8 ± 2.12 - 5.42%. The precision of the assay was satisfactory; RSD was 2.47 - 4.46 and 3.24 - 5.27% for the intra- and inter-assay precision, respectively. The analytical procedure is convenient, and one can analyze ~ 200 samples per working day, facilitating the processing of large-number batch of samples. The proposed ELISA has a great value in routine analysis of ROS for its pharmacokinetic studies.

Design, synthesis and pharmacophoric model building of novel substituted nicotinic acid hydrazones with potential antiproliferative activity.

Novel 6-aryl-2-methylnicotinic acid hydrazides 4a-c and their corresponding hydrazones 5a-c and 6a-i were synthesized. X-ray single crystal diffraction of 6h confirmed the chemical structure of hydrazones 6a-i. Antiproliferative activity of the synthetic compounds was investigated against K562 leukemia cell lines. Variable cell growth inhibitory activities were obtained with IC50 range from 24.99 to 66.78 µM where the compound 6c exhibited the maximum activity. Structure activity relationship analysis has been performed and a common pharmacophore model for the synthesized derivatives has been obtained by using the pharmacophore elucidation module of the software MOE. The best model obtained is characterized by two projected locations of potential H-bond donors (F 3 and F4) and two Aromatic annotations (F1 and F2).

2-(2-{[4-Oxo-3-(2-phenyl-eth-yl)-3,4-dihydro-quinazolin-2-yl]sulfan-yl}eth-yl)-2,3-dihydro-1H-isoindole-1,3-dione.

In the title compound, C(26)H(21)N(3)O(3)S, the quinazolinyl group is essentially planar [r.m.s. deviation for the 10 non-H atoms = 0.057 Å]. The isoindoline-1,3-dione group is linked by an SCH(2)CH(2) chain to the pyrimidinyl C atom that lies between the two N atoms. Also, the phenyl group is linked by a CH(2)CH(2) chain at the N atom adjacent to the carbonyl group. This results in a conformation with these substituents lying to either side of the central quinazolinyl unit, with the former being approximately parallel [dihedral angle = 4.93 (7)°], and the phenyl group being inclined [dihedral angle = 71.61 (9)°] to the central quinazolinyl fused-ring system. In the crystal, mol-ecules are consolidated into a three-dimensional architecture by C-H⋯O inter-actions, involving all three carbonyl-O atoms, and π-π inter-actions occurring between the pyrimidinyl and isoindole-benzene rings [inter-centroid distance = 3.5330 (13) Å].