1
|
Young LM, Geldenhuys WJ, Domingo OC, Malan SF, Van der Schyf CJ. Synthesis and Biological Evaluation of Pentacycloundecylamines and Triquinylamines as Voltage-Gated Calcium Channel Blockers. Arch Pharm (Weinheim) 2016; 349:252-67. [PMID: 26892182 PMCID: PMC5482218 DOI: 10.1002/ardp.201500293] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 01/27/2016] [Accepted: 01/27/2016] [Indexed: 01/21/2023]
Abstract
Preclinical studies for neurodegenerative diseases have shown a multi-targeted approach to be successful in the treatment of these complex disorders with several pathoetiological pathways. Polycyclic compounds, such as NGP1-01 (7a), have demonstrated the ability to target multiple mechanisms of the complex etiology and are referred to as multifunctional compounds. These compounds have served as scaffolds with the ability to attenuate Ca(2+) overload and excitotoxicity through several pathways. In this study, our focus was on mitigating Ca(2+) overload through the L-type calcium channels (LTCC). Here, we report the synthesis and biological evaluation of several novel polycyclic compounds. We determined the IC50 values for both the pentacycloundecylamines and the triquinylamines by means of a high-throughput fluorescence calcium flux assay utilizing Fura-2/AM. The potential of these compounds to offer protection against hydrogen peroxide-induced cell death was also evaluated. Overall, 8-benzylamino-8,11-oxapentacyclo[5.4.0.0(2,6) .0(3,10) .0(5,9) ]undecane (NGP1-01, 7a) had the most favorable pharmacological profile with an IC50 value of 86 µM for LTCC inhibition and significant reduction of hydrogen peroxide-induced cell death. In general, the triquinylamines were more active as LTCC blockers than the oxa-pentacycloundecylamines. The aza-pentacycloundecylamines were potent LTCC inhibitors, with 8-hydroxy-N-phenylethyl-8,11-azapentacyclo[5.4.0.0(2,6) .0(3,10) .0(5,9) ]undecane (8b) also able to offer significant protection in the cell viability assays.
Collapse
Affiliation(s)
- Lois-May Young
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
- Pharmaceutical Chemistry, School of Pharmacy, North-West University, Potchefstroom, South Africa
| | - Werner J. Geldenhuys
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Olwen C. Domingo
- Pharmaceutical Chemistry, School of Pharmacy, North-West University, Potchefstroom, South Africa
| | - Sarel F. Malan
- Pharmaceutical Chemistry, School of Pharmacy, North-West University, Potchefstroom, South Africa
- School of Pharmacy, University of the Western Cape, Bellville, South Africa
| | - Cornelis J. Van der Schyf
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, Idaho State University, Pocatello, ID, USA
| |
Collapse
|
2
|
Xia Y, Boydston AJ, Yao Y, Kornfield JA, Gorodetskaya IA, Spiess HW, Grubbs RH. Ring-expansion metathesis polymerization: catalyst-dependent polymerization profiles. J Am Chem Soc 2009; 131:2670-7. [PMID: 19199611 PMCID: PMC2658644 DOI: 10.1021/ja808296a] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ring-expansion metathesis polymerization (REMP) mediated by recently developed cyclic Ru catalysts has been studied in detail with a focus on the polymer products obtained under varied reaction conditions and catalyst architectures. Depending upon the nature of the catalyst structure, two distinct molecular weight evolutions were observed. Polymerization conducted with catalysts bearing six-carbon tethers displayed rapid polymer molecular weight growth which reached a maximum value at ca. 70% monomer conversion, resembling a chain-growth polymerization mechanism. In contrast, five-carbon-tethered catalysts led to molecular weight growth that resembled a step-growth mechanism with a steep increase occurring only after 95% monomer conversion. The underlying reason for these mechanistic differences appeared to be ready release of five-carbon-tethered catalysts from growing polymer rings, which competed significantly with propagation. Owing to reversible chain transfer and the lack of end groups in REMP, the final molecular weights of cyclic polymers was controlled by thermodynamic equilibria. Large ring sizes in the range of 60-120 kDa were observed at equilibrium for polycyclooctene and polycyclododecatriene, which were found to be independent of catalyst structure and initial monomer/catalyst ratio. While six-carbon-tethered catalysts were slowly incorporated into the formed cyclic polymer, the incorporation of five-carbon-tethered catalysts was minimal, as revealed by ICP-MS. Further polymer analysis was conducted using melt-state magic-angle spinning (13)C NMR spectroscopy of both linear and cyclic polymers, which revealed little or no chain ends for the latter topology.
Collapse
Affiliation(s)
- Yan Xia
- Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | | | | | | | | | | | | |
Collapse
|
3
|
Lewandowski G, Gruszkowska E, Milchert E. The influence of the solvent on the epoxidation of cis,trans,trans-1,5,9-cyclododecatriene to trans-1,2-epoxy-cis,trans-5,9-cyclododecadiene by catalytic system tert-butyl hydroperoxide/Mo(CO)6. J Hazard Mater 2005; 120:45-50. [PMID: 15811663 DOI: 10.1016/j.jhazmat.2004.12.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2004] [Revised: 12/30/2004] [Accepted: 12/30/2004] [Indexed: 05/24/2023]
Abstract
The epoxidation of cis,trans,trans-1,5,9-cyclododecatriene to trans-1,2-epoxy- cis,trans-5,9-cyclododecadiene with the use of commercial solution of tert-butyl hydroperoxide in various organic solvents: tert-butyl peroxide, isooctane, decane, and nonane was investigated. The process was investigated in different experimental conditions. The best results were achieved with the application of tert-butyl hydroperoxide in isooctane. A significant influence of the nature of the solvent on the results of trans-1,2-epoxy-cis,trans-5,9-cyclododecadiene synthesis was found.
Collapse
Affiliation(s)
- Grzegorz Lewandowski
- Institute of Organic Chemical Technology, Technical University of Szczecin, 70-322 Szczecin, Pułaskiego 10, Poland.
| | | | | |
Collapse
|
4
|
Abstract
Musk odorants are one of the most important classes of fragrances in perfumery because they impart sensuality to perfume-oil compositions. Among the three well-known classes of musks, a new and very exciting generation of musk odorants, the so-called alicyclic musks, was discovered recently, of which Helvetolide (2) and Romandolide (3) are the most popular representatives so far. To find new, structurally related alicyclic musks, we have synthesized a library of 114 unique alicyclic molecules with modified cyclohexyl moieties. The olfactory properties of all compounds were evaluated to identify the structural requirements to be met for a musk odorant.
Collapse
Affiliation(s)
- Marcus Eh
- Symrise GmbH & Co. KG, Mühlenfeldstrasse 1, D-37603 Holzminden.
| |
Collapse
|
5
|
Aam BB, Myhre O, Fonnum F. Transcellular signalling pathways and TNF-alpha release involved in formation of reactive oxygen species in rat alveolar macrophages exposed to tert-butylcyclohexane. Arch Toxicol 2003; 77:678-84. [PMID: 13680096 DOI: 10.1007/s00204-003-0507-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2003] [Accepted: 07/29/2003] [Indexed: 11/24/2022]
Abstract
In the present work, the effects of aliphatic ( n-nonane and n-decane), alicyclic (1,2,4-trimethylcyclohexane and tert-butylcyclohexane, t-BCH) and aromatic (trimethylbenzene and tert-butylbenzene) hydrocarbon solvents on formation of reactive oxygen species (ROS) and the proinflammatory cytokine TNF-alpha in rat alveolar macrophages (AM) have been investigated. Formation of ROS was assessed by monitoring oxidation of 2',7'-dichlorofluorescin to 2',7'-dichlorofluorescein (DCF), and the proinflammatory cytokine tumour necrosis factor alpha (TNF-alpha) was detected using an enzyme-linked immunosorbent assay. DCF fluorescence was elevated in a concentration-dependent manner by the alicyclic hydrocarbons. The involvement of transcellular signalling pathways in the production of ROS by t-BCH, the most active compound, was elucidated by use of specific inhibitors. Preincubation of the AM with the mitogen-activated protein kinase (ERK 1/2) inhibitor U0126, the protein kinase C inhibitor bisindolylmaleimide, the superoxide dismutase inhibitor diethyldithiocarbamate, and the iron ion chelating agent deferoxamine reduced the DCF fluorescence significantly. t-BCH gave an increase in TNF-alpha release. Further, nitric oxide production measured by a modified Griess method, and intracellular calcium concentration measured by fura-2, were increased in the rat AM after exposure to t-BCH.
Collapse
Affiliation(s)
- Berit Bjugan Aam
- VISTA (The Norwegian Academy of Science and Letters/Statoil), PO Box 25, 2027 Kjeller, Norway
| | | | | |
Collapse
|
6
|
Chang D, Wang Z, Heringa MF, Wirthner R, Witholt B, Li Z. Highly enantioselective hydrolysis of alicyclic meso-epoxides with a bacterial epoxide hydrolase from Sphingomonas sp. HXN-200: simple syntheses of alicyclic vicinal trans-diols. Chem Commun (Camb) 2003:960-1. [PMID: 12744319 DOI: 10.1039/b300435j] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hydrolysis of N-benzyloxycarbonyl-3,4-epoxy-pyrrolidine and cyclohexene oxide with the epoxide hydrolase of Sphingomonas sp. HXN-200, respectively, gave the corresponding vicinal trans-diols in high ee and yield, representing the first example of enantioselective hydrolysis of a meso-epoxide with a bacterial epoxide hydrolase.
Collapse
Affiliation(s)
- Dongliang Chang
- Institute of Biotechnology, Swiss Federal Institute of Technology Zurich, ETH-Hoenggerberg, CH-8093 Zurich, Switzerland
| | | | | | | | | | | |
Collapse
|
7
|
Hoshino T, Ohashi S. Importance of the methyl group at C10 of squalene for hopene biosynthesis and novel carbocyclic skeletons with 6/5 + 5/5 + (6) ring system(s). Org Lett 2002; 4:2553-6. [PMID: 12123374 DOI: 10.1021/ol026180u] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Incubation of (6E,10E,14E,18E)-2,6,10,19,23-pentamethyl-tetracosa-2,6,10,14,18,22-hexaene with Alicyclobacillus acidocaldarius hopene cyclase afforded four products having two types of carbocyclic skeletons, i.e., two hopane products and two products having an unprecedented carbocyclic skeleton of 6/5 + 5/5 +6 pentacyclic and 6/5 + 5/5 tetracyclic ring systems. The former two hopane skeletons were formed from the bioconversion of C15-desmethylsqualene and the latter two skeletons from that of C10-desmethylsqualene.
Collapse
Affiliation(s)
- Tsutomu Hoshino
- Department of Applied Biological Chemistry, Faculty of Agriculture, and Graduate School of Science and Technology, Niigata University, Ikarashi, Niigata 950-2181.
| | | |
Collapse
|
8
|
Liu Y, Ali SM, Boge TC, Georg GI, Victory S, Zygmunt J, Marquez RT, Himes RH. A systematic SAR study of C10 modified paclitaxel analogues using a combinatorial approach. Comb Chem High Throughput Screen 2002; 5:39-48. [PMID: 11860338 DOI: 10.2174/1386207023330615] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A library with 63 paclitaxel analogues modified at the C10 position of paclitaxel has been prepared using parallel solution phase synthesis. Most of the C10 analogues were slightly less active than paclitaxel in the tubulin assembly assay and had reduced potency in the B16 melanoma and MCF-7 cell line cytotoxicity assays. These modifications at C10, however, did not lead to the total loss of activity, indicating that the C10 moiety of paclitaxel may not be directly involved in the drug-microtubule interactions, but could influence its binding affinity to P-glycoprotein. Approximately 50% of the analogues demonstrated better activity against the drug resistant cell line MCF7-ADR. However, the increase in activity was 10-fold at most. This result demonstrates that the cytotoxicity against this drug resistant cancer cell line is sensitive to structural changes at the C10 position of paclitaxel. It was also found that the presence of a nitrogen atom in the C10 substituent might play a role in the interaction of analogues with microtubules.
Collapse
MESH Headings
- Animals
- Breast Neoplasms/drug therapy
- Breast Neoplasms/pathology
- Chromatography, Thin Layer
- Combinatorial Chemistry Techniques/methods
- Drug Resistance, Neoplasm
- Fatty Acids/chemistry
- Humans
- Hydrocarbons, Alicyclic/chemistry
- Hydrocarbons, Aromatic/chemistry
- Mass Spectrometry
- Melanoma, Experimental/drug therapy
- Melanoma, Experimental/pathology
- Mice
- Nuclear Magnetic Resonance, Biomolecular
- Paclitaxel/analogs & derivatives
- Paclitaxel/chemical synthesis
- Paclitaxel/toxicity
- Solutions
- Spectrometry, Mass, Fast Atom Bombardment
- Structure-Activity Relationship
- Tumor Cells, Cultured
Collapse
Affiliation(s)
- Yanbin Liu
- Department of Medicinal Chemistry, and the Drug Discovery Program, Higuchi Biosciences Center, University of Kansas, Lawrence, KS 66045, USA
| | | | | | | | | | | | | | | |
Collapse
|
9
|
Abstract
This review presents the latest developments in the field of carba-nucleosides (1994-1998). Special attention is paid to the synthesis of key precursors to those carba-nucleosides that possess significant biological activities or have novel structures.
Collapse
Affiliation(s)
- X F Zhu
- Department of Chemistry, Texas A & M University, College Station 77842-3012, USA
| |
Collapse
|
10
|
Abstract
The present work describes investigations on the bacterial degradation of the alicyclic molecule cyclododecane. It represents a structure where the initial degradative steps have to be similar to a "subterminal" attack as there is no "terminal" part of the molecule. We were able to show that the gram-positive bacterium Rhodococcus ruber CD4 DSM 44394 oxidizes cyclododecane to the corresponding alcohol and ketone, the latter being subject to ring fission by a Baeyer-Villiger oxygenase. This key enzyme is an NADPH- and O2-dependent flavoprotein with a substrate specificity for bigger rings. The further metabolism of the resulting lactone gives rise to an omega-hydroxyalkanoic acid that is susceptible to common beta-oxidation. Due to its alicyclic character and its ring size, cyclododecane is comparable to aliphatic bridge components that are an important element in the coal texture. They contribute to the three-dimensional coal structure and thus could serve as a valuable target for the oxidative abilities of R. ruber CD4 to reduce the molecular mass of coal.
Collapse
Affiliation(s)
- J D Schumacher
- Institut für Mikrobiologie und Biotechnologie, Universität Bonn, Germany
| | | |
Collapse
|
11
|
Bernstein MP, Sandford SA, Allamandola LJ. Hydrogenated polycyclic aromatic hydrocarbons and the 2940 and 2850 wavenumber (3.40 and 3.51 micron) infrared emission features. Astrophys J 1996; 472:L127-L130. [PMID: 11541245 DOI: 10.1086/310376] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The 3150-2700 cm-1 (3.17-3.70 microns) range of the spectra of a number of Ar-matrix-isolated PAHs containing excess H atoms (Hn-PAHs) are presented. This region covers features produced by aromatic and aliphatic C-H stretching vibrations as well as overtone and combination bands involving lower lying fundamentals. The aliphatic C-H stretches in molecules of this type having low to modest excess H coverage provide excellent fits to a number of the weak emission features superposed on the plateau between 3080 and 2700 cm-1 (3.25 and 3.7 microns) in the spectra of many planetary nebulae, reflection nebulae, and H II regions. Higher H coverage is implied for a few objects. We compare these results in context with the other suggested identifications of the emission features in the 2950-2700 cm-1 (3.39-3.70 microns) region and briefly discuss their astrophysical implications.
Collapse
Affiliation(s)
- M P Bernstein
- Astrophysics Branch, NASA Ames Research Center, Moffett Field, CA 94035-1000, USA
| | | | | |
Collapse
|