Day 2 :
- Medicinal Chemistry and Drug Design
Location: Edinburgh, Scotland
Chair
Orazio Nicolotti
University of Bari, Italy
Session Introduction
Daniela Andrei
Dominican University, USA
Title: Diazeniumdiolates as HNO/NO donors: Synthesis and biological activity
Time : 13:40-14:05
Biography:
Daniela Andrei earned her PhD at Florida International University in Miami, Florida and after her graduation in 2006, she worked as a postdoctoral fellow for the National Institutes of Health/National Institute of Cancer at Frederick, Maryland. She joined Dominican University in River Forest in 2008 where she serves as a full Professor of Chemistry performing research in synthetic organic and medicinal chemistry. Her research work is on nitric oxide chemistry. She has been working on the synthesis of small biological active molecules known as diazeniumdiolate or NONOates with the goal of expanding the availability of primary amine diazeniumdiolates. She has published several scientific papers in different areas of organic chemistry and is an inventor of 2 U.S. patents.
Abstract:
Diazeniumdiolate ions, also known as NONOates, are extensively used in biochemical, physiological and pharmacological studies due to their ability to slowly release nitric oxide (NO.) and/or their congeneric nitroxyl (HNO) (Fig 1). NONOates of secondary amines have traditionally been used as NO donors and have become the standard for NO donating compounds in chemistry and biology. However, primary amine diazeniumdiolates have been less studied, and essentially IPA/NO and a few alicyclic amine diazeniumdiolates are the only representatives of this class of compounds. The purpose of this work was to synthesize a series of primary amine-based diazeniumdiolates as HNO donors and to determine their efficacy as anticancer and antifungal agents in vivo. Our compounds demonstrated a reduction in proliferation of ovarian and AML cancer cells. Similarly, they have also demonstrated some antifungal activity against various strains of Fusarium. We also used mouse RAW and human THP-1 macrophages cell line to test the compounds for anti- or pro-inflammatory properties, if any. To this end, we determined the impact of individual molecules on the LPS-induced M1 polarization and IL-4-induced M2 polarization, independently. We employed qRT-PCR and flow cytometry techniques to measure M1 and M2 phenotype after treatment with LPS or IL-4, respectively, in the absence or presence of our compounds. In order to gain an insight into the mechanism of action, we simultaneously quantified IEX-1 mRNA expression levels in response to treatment with different doses of compounds. In conclusion, the synthesis and the biological activity of these compounds are going to be discussed in detail during the presentation.
Daniela Andrei
Dominican University, USA
Title: Diazeniumdiolates as HNO/NO donors: Synthesis and biological activity
Biography:
Daniela Andrei earned her PhD at Florida International University in Miami, Florida and after her graduation in 2006, she worked as a postdoctoral fellow for the National Institutes of Health/National Institute of Cancer at Frederick, Maryland. She joined Dominican University in River Forest in 2008 where she serves as a full Professor of Chemistry performing research in synthetic organic and medicinal chemistry. Her research work is on nitric oxide chemistry. She has been working on the synthesis of small biological active molecules known as diazeniumdiolate or NONOates with the goal of expanding the availability of primary amine diazeniumdiolates. She has published several scientific papers in different areas of organic chemistry and is an inventor of 2 U.S. patents
Abstract:
Diazeniumdiolate ions, also known as NONOates, are extensively used in biochemical, physiological and pharmacological studies due to their ability to slowly release nitric oxide (NO.) and/or their congeneric nitroxyl (HNO) (Fig 1). NONOates of secondary amines have traditionally been used as NO donors and have become the standard for NO donating compounds in chemistry and biology. However, primary amine diazeniumdiolates have been less studied, and essentially IPA/NO and a few alicyclic amine diazeniumdiolates are the only representatives of this class of compounds. The purpose of this work was to synthesize a series of primary amine-based diazeniumdiolates as HNO donors and to determine their efficacy as anticancer and antifungal agents in vivo. Our compounds demonstrated a reduction in proliferation of ovarian and AML cancer cells. Similarly, they have also demonstrated some antifungal activity against various strains of Fusarium. We also used mouse RAW and human THP-1 macrophages cell line to test the compounds for anti- or pro-inflammatory properties, if any. To this end, we determined the impact of individual molecules on the LPS-induced M1 polarization and IL-4-induced M2 polarization, independently. We employed qRT-PCR and flow cytometry techniques to measure M1 and M2 phenotype after treatment with LPS or IL-4, respectively, in the absence or presence of our compounds. In order to gain an insight into the mechanism of action, we simultaneously quantified IEX-1 mRNA expression levels in response to treatment with different doses of compounds. In conclusion, the synthesis and the biological activity of these compounds are going to be discussed in detail during the presentation.
Letizia Giampietro
University of Chieti, Italy
Title: Novel phenyldiazenyl fibrate analogues as PPAR agonists: Design, synthesis and pharmacological evaluation
Biography:
Letizia Giampietro has completed Degree in Pharmacy (2000) and received her PhD in Medicinal Chemistry (2003) from the University “G. d’Annunzio” of Chieti (Italy). From 2006 to date, she is Assistant Professor of Pharmaceutical Analysis. She has published more than 45 papers in reputed journals. Her research interests include medicinal chemistry and are above all focused towards the synthesis of fibrate derivatives active on Peroxisome Proliferator-Activate Receptors (PPARs). Lately, her research is direct to the synthesis of small molecules with anticancer, neuroprotective and antioxidant activity.
Abstract:
Peroxisome Proliferator-Activated Receptors (PPARs) are nuclear hormone receptors expressed especially in metabolically active tissues. Three different isoforms namely PPARï¡, PPARï§ and PPARï¤ are identified; they play important roles in lipid and glucose homeostasis. The research of dual PPARï¡/ï§ and pan PPAR α/γ/δ agonists could be useful to treat simultaneously dyslipidemia and type 2 diabetes mellitus, reducing side effects of selective PPAR agonists.1 Fibrates active as PPAR agonists have, as typical pharmacophore, a carboxylic acid head and an aromatic ring with or without different spacers. Based on this pharmacophore, in the past, we reported synthesis and biological evaluation of various fibrate analogues. These compounds showed good activation of PPARs.2,3 In particular, a dual PPARα/γ agonist, named GL479 (αEC50=0.6 ïM and γEC50=1.4 ïM), was identified (Figure 1; R = H; X = O; Y = CH2).4 This compound was crystallized with PPARα and PPARγ in order to explain its particular binding mode with the receptors ligand binding domain.5 In view of these results, and to gain more insight on the structure-activity relationships, we synthesized new GL479 analogues with the oxygen of the linker in para to the 2-methyl-2-phenoxypropanoic group and with different substituents in para to the phenyldiazenyl moiety (Figure 1). All compounds were tested in a cell-based transactivation assay to evaluate the agonist activity toward the human PPARα, -γ and -β/δ. The obtained results led to the identification of some fibrate derivatives with promising activity on the three PPAR isoforms. In particular, a docking study of the best candidate clarified the possible binding modes with PPARα, -γ and -β/δ. Moreover, in vitro and ex vivo studies on tested compounds allowed us to discover an interesting lead for the development of a new class of PPAR agonists exploitable for therapy of metabolic syndrome.
Alex R Khomutov
Russian Academy of Sciences, Russia
Title: Isomers and diastereomers of C-methylated spermidine and spermine: Synthesis and biochemical application
Biography:
Alex R.Khomutov principle investigator, Engelhardt Institute of Molecular Biology, Moscow, Russia. He graduated Chemical Faculty of Moscow State University in 1976. He got PhD and later D.Sc. degrees in Bioorganic Chemistry in Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow. The main field of the interests are design and synthesis of the inhibitors/unnatural substrates of the enzymes of amino acids metabolism, including those related to biosynthesis and catabolism of biogenic polyamines spermine and spermidine, and investigation of the interaction of these analogues with enzymes and activity in cell cultures. In 2017 he was a chair of Polyamines Gordon Research Conference. A.R.Khomutov is a co-author of more than 120 papers in per-reviewed Journals.
Abstract:
Statement of the Problem: The polyamines, spermidine (1,8-diamino-4-azaoctane, Spd) and spermine (1,12- diamino-4,9-diazadodecane, Spm) are ubiquitous organic polycations present in all eukaryotic cells in µM-mM concentrations and involved in the regulation of numerous vital processes including the differentiation and growth of cells1. Disturbances of polyamines metabolism are associated with the development of many diseases, including malignant tumors, decreased immune response, some types of pancreatitis, Snyder-Robinson's syndrome, and even type 2 diabetes1. Biological evaluation of rationally designed polyamine analogs is one of the cornerstones of polyamine research having obvious basic and practical values. Here we synthesized and characterized C-methylated Spm and Spd analogues possessing a biochemically useful set of properties. Methodology & Theoretical Orientation: The synthesis of title compounds was performed using known methods starting from amino alcohols by subsequent elongation of polyamine backbone, or using convergent synthesis in the case of bis-methylated Spm derivatives2. Findings: Obtained data demonstrated that the biochemical properties of C-methylated polyamine analogs can be regulated by changing the position of the methyl substituent, and at more precise level by changing the configuration of chiral center2-4. Hidden stereospecificity (natural substrates are achiral) was shown for the enzymes of polyamine metabolism using title compounds2. An original approach to alter stereospecificity of FAD-dependent N-acetylpolyamine oxidase (APAO) and to alter stereospecificity and regioselectivity of yeast polyamine oxidase (Fms1) was suggested2,4. Conclusion & Significance: The first metabolically stable functionally active mimetics of Spd, i.e. (R)-1,8-diamino-3-methyl-4-azaoctane and Spm, i.e. (R,R)-2,13-diamino-5,10- diazatetradecane, being suitable for the investigation of the individual cellular functions of partly interchangeable and easily interconvertible Spm and Spd were found2,3.
Alessandra Ammazzalorso
University of Chieti, Italy
Title: Synthesis and cytotoxicity evaluation of novel amide and sulfonimide PPARaï¡ antagonists
Time : 14:55-15:20
Biography:
Alessandra Ammazzalorso obtained her PhD in Pharmaceutical Sciences from the University of Chieti, Italy, in 2001. Since 2004 she has been an Assistant Professor of Medicinal Chemistry at the University of Chieti Department of Pharmacy. Her research interests include the design and synthesis of small-molecule drugs, mainly compounds targeting Peroxisome Proliferator-Activated Receptors, aromatase and nitric oxide synthase.
Abstract:
Peroxisome Proliferator-Activated Receptors (PPARs) have been widely studied in the last decades, and they attracted the attention of scientists as promising therapeutic targets. Intensive efforts by researchers produced a wide panel of drugs targeting the three PPAR subtypes (PPARï¡, PPARï§, PPARï¤) able to modulate important metabolic functions. PPAR activation is involved in several physiologic pathways, as lipid and glucose metabolism, insulin sensitivity, energy homeostasis, and cell differentiation. Fibrates and thiazolidinediones, respectively synthetic PPARï¡ and PPARï§ agonists, are currently used for the treatment of hyperlipidemia and hyperglycemia, in patients affected by type 2 diabetes and metabolic syndrome. In recent years, an increased expression of PPARï¡ has been found in different tumors: it is well known that cancer cells present altered metabolic pathways, switching from the glycolysis to fatty acid oxidation metabolism. In this scenario, PPARï¡ antagonists emerged as novel potential drugs in tumors overexpressing PPARï¡, by interfering with cellular survival and metastasis formation [1]. In vitro anticancer effects were found for PPARï¡ antagonists in chronic lymphocytic leukemia [2], renal cancer [3], colorectal and pancreatic cancer [4], paraganglioma [5]. In this study we report on the synthesis of novel amide and sulfonimide PPARï¡ antagonists, starting from the structure of PPARï¡ agonists, previously synthesized in our laboratory. Furthermore, we explored the possible cytotoxicity of the novel compounds in different cancer cell lines (colorectal, pancreatic and paraganglioma) expressing PPARï¡
Mary Anti Chama
University of Ghana, Ghana
Title: Antibacteria, antiparasitic and in silico studies of dichapetalum madagascariense Poire
Biography:
Mary Chama has her research interest in the area of Medicinal plant Natural Product where she and her team are involved in isolation, characterization, and biological testing of active compounds from medicinal plants. Biological testing for anticancer, tropical infectious disease such as anti-hookworm, antischistosomiasis, antitrypanosomiasis and antimalarial has been her recent focus. She has worked on Scoparia dulcis, plants from some Dichapetalum species and currently researching on species from the Fabaceae and Annonaceae families. Her research also involves the application of in silico studies towards understanding the mode of action of therapeutic medicinal plants and active isolates which she acquired on her Post-doctoral fellowship at the Chemistry department of the University of Cambridge in UK.
Abstract:
Dichapetalum madagascariense (Dichapetalaceae) is used to treat bacterial infections, jaundice, urethritis and viral hepatitis. Its root has been investigated to contain broad spectrum biologically active dichapetalins. To evaluate the plant’s antibacterial and antiparasitic potentials coupled with in silico methods, we isolated and identified the known dichapetalins A and M from the roots. Both dichapetalins were tested together with the leaf (DML) and root (DMR) ethanol extracts on six ATCC bacteria strains (Shigella flexneri, Bacillus cereus, Salmonella paratyphi B, Listeria monocytogenes, Escherichia coli, Staphylococcus aureus) and three parasites; Trypanosoma brucei brucei, Leishmania donovani and Plasmodium falciparum 3D7 strain using the Alamar Blue Assay. Dichapetalins A and M were potent against B. cereus with IC50, 11.15 and 3.15 µg/ml respectively compared with ampicillin (IC50, 1.70 µg/ml). DML (IC50, 0.45 µg/ml) was threefold more potent than ampicillin (IC50, 1.5 µg/ml) against S. paratyphi B and more active (IC50, 12.65 µg/ml) against S. flexneri than ampicillin (IC50, 14.02 µg/ml). Dichapetalins A (IC50, 74.22 µg/ml) and M (IC50, 72.34 µg/ml) were only active against T. b. brucei compared to the standard extract of Coptis japonica (IC50, 3.6 µg/ml) and suramin (IC50, 4.96 µg/ml). Dichapetalin M showed moderate activity against L. donovani (IC50, 0.21 µg/ml) with IC50, 16.80 µg/ml. DML and DMR gave IC50, 9.66 and 11.17 µg/ml respectively against T. b. brucei when compared with C. japonica (IC50, 3.6 µg/ml) and suramin (IC50, 4.96 µg/ml). Target prediction with PIDGIN software indicated NR1I2 as a plausible target for dichapetalin A. Protein BLASTing the protein sequence of this xenobiotic sensor nuclear receptor to the used species suggested that dichapetalin A may have a bacteriostatic effect through the nucleotide hydrolase NUDIX (T. brucei), or the uncharacterised protein YagA or ydbH (S. flexneri). However, the understanding of the exact mechanism of the dichapetalin’s antibiotic effect requires further research.
James K Bashkin
University of Missouri-St. Louis, USA
Title: Broad-spectrum binding to human papillomavirus DNA
Biography:
James Bashkin completed his D.Phil. at the age of 24 years from Oxford University and postdoctoral studies from Harvard University’s Department of Chemistry. He is Professor of Chemistry and Biochemistry at the University of Missouri-St. Louis and Co-Founder and Director of Chemistry at NanoVir LLC, an antiviral company. He also worked at Monsanto, Pharmacia, and Pfizer, has published more than 73 papers in reputed journals, and has served as an editorial board member and/or associate editor of numerous journals, most notably as an Editorial Advisory Board member of Chemical Reviews from 1991-2014.
Abstract:
We describe the biophysical behavior of polyamides active against human papillomavirus (HPV) types 16, 18, and 31. The MWs of active polyamides are high, and we observed active uptake for human keratinocytes infected with HPV. We have measured binding constants for a group of active anti-HPV compounds on viral DNA, largely but not exclusively in the long control region (LCR). All of our most active polyamides to date contain guanidine and tetramethylguanidine N-termini, in partial mimicry of the natural product netropsin. These compounds include asymmetric hairpins as shown below, where not every heterocycle finds an analogous ring in the opposite strand of the hairpin. Binding constants were determined by quantitative DNase I footprinting and capillary electrophoresis. Binding constants do not correlate with antiviral activity, but there is a loose correlation between binding promiscuity and antiviral efficacy in cell culture. These and other recent results, including new observations of polyamide-DNA binding stoichiometry, are of interest. In particular, greater than 1:1 polyamide:DNA stoichiometries were observed. Evidence for such stoichiometries has been reported in the literature without comment, and here we will interpret these results as per our recent paper.1