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Hara Y, Honda T, Arakawa K, Ota K, Kamaike K, Miyaoka H. Total Synthesis of ent-Ascospiroketal B. J Org Chem 2018; 83:1976-1987. [PMID: 29389118 DOI: 10.1021/acs.joc.7b02925] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ascospiroketal B was isolated from a marine-derived fungus as a structurally unique polyketide possessing a rare tricyclic core including 5,5-spiroketal-γ-lactone. An asymmetric total synthesis of ent-ascospiroketal B was achieved using an original synthetic route. The synthesis included the stereoselective construction of 5,5-spiroketal for ascospiroketal B and stereocontrolled construction of a quaternary asymmetric carbon by rearrangement of a trisubstituted epoxide.
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Affiliation(s)
- Yoshiyori Hara
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Tatsuya Honda
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Kazuto Arakawa
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Koichiro Ota
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Kazuo Kamaike
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Hiroaki Miyaoka
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
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Fodran P, Minnaard AJ. Catalytic synthesis of enantiopure mixed diacylglycerols – synthesis of a major M. tuberculosis phospholipid and platelet activating factor. Org Biomol Chem 2014; 11:6919-28. [PMID: 24191360 DOI: 10.1039/c3ob41483c] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient catalytic one-pot synthesis of TBDMS-protected diacylglycerols has been developed, starting from enantiopure glycidol. Subsequent migration-free deprotection leads to stereo- and regiochemically pure diacylglycerols. This novel strategy has been applied to the synthesis of a major Mycobacterium tuberculosis phospholipid, its desmethyl analogue, and platelet activating factor.
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Varvogli AAC, Fylaktakidou KC, Farmaki T, Stefanakis JG, Koumbis AE. Versatile Synthesis of 1- O-(ω-Aminolauryl)-I(4,5)P 2. European J Org Chem 2012. [DOI: 10.1002/ejoc.201200726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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4
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Wymann MP, Schultz C. The chemical biology of phosphoinositide 3-kinases. Chembiochem 2012; 13:2022-35. [PMID: 22965647 DOI: 10.1002/cbic.201200089] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 07/13/2012] [Indexed: 01/14/2023]
Abstract
Since its discovery in the late 1980s, phosphoinositide 3-kinase (PI3K), and its isoforms have arguably reached the forefront of signal transduction research. Regulation of this lipid kinase, its functions, its effectors, in short its entire signaling network, has been extensively studied. PI3K inhibitors are frequently used in biochemistry and cell biology. In addition, many pharmaceutical companies have launched drug-discovery programs to identify modulators of PI3Ks. Despite these efforts and a fairly good knowledge of the PI3K signaling network, we still have only a rudimentary picture of the signaling dynamics of PI3K and its lipid products in space and time. It is therefore essential to create and use novel biological and chemical tools to manipulate the phosphoinositide signaling network with spatial and temporal resolution. In this review, we discuss the current and potential future tools that are available and necessary to unravel the various functions of PI3K and its isoforms.
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Affiliation(s)
- Matthias P Wymann
- Institute of Biochemistry & Genetics, Department of Biomedicine, University of Basel, Mattenstrasse 28, 4058 Basel, Switzerland
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Bidlingmaier S, Wang Y, Liu Y, Zhang N, Liu B. Comprehensive analysis of yeast surface displayed cDNA library selection outputs by exon microarray to identify novel protein-ligand interactions. Mol Cell Proteomics 2010; 10:M110.005116. [PMID: 21127146 DOI: 10.1074/mcp.m110.005116] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phosphatidylinositides are important signaling molecules that interact with a myriad of cellular proteins, many of which remain unidentified. We previously screened a yeast surface displayed human proteome library to identify protein fragments with affinity for the phosphatidylinositides, phosphatidylinositol-4,5-bisphosphate and phosphatidylinositol-3,4,5-trisphosphate. Much of the diversity in the screened selection outputs was represented by clones present at low frequencies, suggesting that a significant number of additional phosphatidylinositide-binding protein fragments might be present in the selection outputs. In the studies described in this report, we developed a novel cDNA library analysis method and comprehensively analyzed the polyclonal selection outputs from the phosphatidylinositol-4,5-bisphosphate and phosphatidylinositol-3,4,5-trisphosphate selections using a high-density exon microarray. In addition to the nine previously reported phosphatidylinositide-binding protein fragments, we identified 37 new phosphatidylinositide-binding candidates. Nine of 37 contain known phosphatidylinositide-binding domains, whereas the remaining 28 contain no known phosphatidylinositide-binding domain. We cloned and confirmed phosphatidylinositide binding by fluorescence-activated cell sorting for 17 of these novel candidate protein fragments. Our experiments suggest that phosphatidylinositide binding by these 17 novel protein fragments is dependent on both the inositol phosphate "headgroup" and the lipid "tail." This is in contrast with the PH domain containing fragments we tested, for which the inositol phosphate headgroup was sufficient for binding. The novel PtdIns-binding fragments come from a wide variety of proteins, including splicing factors, transcription factors, a kinase, and a polymerase. Intriguingly, 11 of the phosphatidylinositide-binding protein fragments are from nuclear proteins, including four containing homeobox domains. We found that phosphatidylinositides and double-stranded DNA oligonucleotides derived from homeobox domain target sequences compete for binding to homeobox domain-containing protein fragments, suggesting a possible mechanism for phospholipid-dependent transcriptional regulation. FACS enrichment of target-binding clones in yeast human cDNA display libraries coupled with comprehensive analysis of the selection output by DNA microarray analysis is an effective method for investigating common as well as rare protein interactions. In particular, this method is well suited for the study of small molecule/protein and drug/protein interactions.
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Affiliation(s)
- Scott Bidlingmaier
- UCSF Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, CA 94110, USA
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Best MD, Zhang H, Prestwich GD. Inositol polyphosphates, diphosphoinositol polyphosphates and phosphatidylinositol polyphosphate lipids: Structure, synthesis, and development of probes for studying biological activity. Nat Prod Rep 2010; 27:1403-30. [DOI: 10.1039/b923844c] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Conway SJ, Gardiner J, Grove SJA, Johns MK, Lim ZY, Painter GF, Robinson DEJE, Schieber C, Thuring JW, Wong LSM, Yin MX, Burgess AW, Catimel B, Hawkins PT, Ktistakis NT, Stephens LR, Holmes AB. Synthesis and biological evaluation of phosphatidylinositol phosphate affinity probes. Org Biomol Chem 2009; 8:66-76. [PMID: 20024134 DOI: 10.1039/b913399b] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The synthesis of the complete family of phosphatidylinositol phosphate analogues (PIPs) from five key core intermediates A-E is described. These core compounds were obtained from myo-inositol orthoformate 1 via regioselective DIBAL-H and trimethylaluminium-mediated cleavages and a resolution-protection process using camphor acetals 10. Coupling of cores A-E with phosphoramidites 34 and 38, derived from the requisite protected lipid side chains, afforded the fully-protected PIPs. Removal of the remaining protecting groups was achieved via hydrogenolysis using palladium black or palladium hydroxide on carbon in the presence of sodium bicarbonate to afford the complete family of dipalmitoyl- and amino-PIP analogues 42, 45, 50, 51, 58, 59, 67, 68, 76, 77, 82, 83, 92, 93, 99 and 100. Investigations using affinity probes incorporating these compounds have identified novel proteins involved in the PI3K intracellular signalling network and have allowed a comprehensive proteomic analysis of phosphoinositide interacting proteins.
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Affiliation(s)
- Stuart J Conway
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
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Ter Horst B, Seshadri C, Sweet L, Young DC, Feringa BL, Moody DB, Minnaard AJ. Asymmetric synthesis and structure elucidation of a glycerophospholipid from Mycobacterium tuberculosis. J Lipid Res 2009; 51:1017-22. [PMID: 19965610 DOI: 10.1194/jlr.m001982] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A glycerophospholipid (1-O-tuberculostearoyl-2-O-palmitoyl-sn-glycero-3-phosphoethanolamine) from Mycobacterium tuberculosis was isolated from the reference strain H37Rv. The molecular structure of this tuberculostearoyl [(R)-10-methyloctadecyl] and palmitoyl containing phosphatidylethanolamine (PE) has been resolved. The substitution pattern on the glycerol backbone could be determined by comparison of the isolate to the two synthetically prepared regioisomers. MS/MS analysis was used to determine its molecular structure. Production of this synthetic version of mycobacterial PE in high yield, with a stereochemically correct and pathogen-specific fatty acyl group, can be used as a standard in LC-MS based lipidomic analyses to detect trace amounts of mycobacterial PE in human blood, sputum, or tissues as a marker of infection by mycobacteria.
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Affiliation(s)
- Bjorn Ter Horst
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
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Smith MD, Sudhahar CG, Gong D, Stahelin RV, Best MD. Modular synthesis of biologically active phosphatidic acid probes using click chemistry. MOLECULAR BIOSYSTEMS 2009; 5:962-72. [PMID: 19668861 PMCID: PMC5985520 DOI: 10.1039/b901420a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Phosphatidic acid (PA) is an important signaling lipid that plays roles in a range of biological processes including both physiological and pathophysiological events. PA is one of a number of signaling lipids that can act as site-specific ligands for protein receptors in binding events that enforce membrane association and generally regulate both receptor function and subcellular localization. However, elucidation of the full scope of PA activities has proven problematic, primarily due to the lack of a consensus sequence among PA-binding receptors. Thus, experimental approaches, such as those employing lipid probes, are necessary for characterizing interactions at the molecular level. Herein, we describe an efficient modular approach to the synthesis of a range of PA probes that employs a late stage introduction of reporter groups. This strategy was exploited in the synthesis of PA probes bearing fluorescent and photoaffinity tags as well as a bifunctional probe containing both a photoaffinity moiety and an azide as a secondary handle for purification purposes. To discern the ability of these PA analogs to mimic the natural lipid in protein-binding properties, each compound was incorporated into vesicles for binding studies using a known PA receptor, the C2 domain of PKCalpha. In these studies, each compound exhibited binding properties that were comparable to those of synthetic PA, indicating their viability as probes for effectively studying the activities of PA in cellular processes.
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Affiliation(s)
- Matthew D Smith
- Department of Chemistry, The University of Tennessee, Knoxville, TN 37996, USA
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Smith MD, Gong D, Sudhahar CG, Reno JC, Stahelin RV, Best MD. Synthesis and convenient functionalization of azide-labeled diacylglycerol analogues for modular access to biologically active lipid probes. Bioconjug Chem 2008; 19:1855-63. [PMID: 18683963 DOI: 10.1021/bc8001002] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cell membrane lipids have been identified as key participants in cell signaling activities. One important role is their involvement as site-specific ligands in protein-membrane binding interactions, which result in the anchoring of peripheral proteins onto cellular membranes. These events generally regulate protein function and localization and have been implicated in both normal physiological processes and those pertaining to disease state onset. Thus, it is important to elucidate the details of interactions at the molecular level, such as lipid-binding specificities and affinities, the location of receptor binding domains and multivalency in binding. For this purpose, we have designed and developed azido-tagged lipid analogues as conveniently functionalizable lipid probe scaffolds. Herein, we report the design and synthesis of the initial structure of this type, diacylglycerol analogue 2, which contains an azide tag at the sn-1 position of the lipid headgroup. Direct functionalization of this compound with a range of reporter groups has been performed to illustrate the facile access to probes of use for characterizing binding. Quantitative lipid-binding studies using protein kinase C, a known DAG-binding receptor, demonstrate that these probes are active mimetics of natural DAG. Thus, these DAG probes will serve as robust sensors for studies aimed at understanding binding interactions and as precursors for the development of analogous probes of more complex phospholipids and glycolipids.
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Affiliation(s)
- Matthew D Smith
- Department of Chemistry, The University of Tennessee, Knoxville, Tennessee 37996, USA
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Perrin D, Martin T, Cambet Y, Frémaux C, Scheer A. Overcoming the Hurdle of Fluorescent Compounds in Kinase Screening: A Case Study. Assay Drug Dev Technol 2006; 4:185-96. [PMID: 16712422 DOI: 10.1089/adt.2006.4.185] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
In the field of screening in general and especially in the kinase area, taking into consideration throughput and cost, fluorescence- and luminescence-based assays have been developed as alternatives to radioactivity-based assays. However, fluorescence-based technologies are not devoid of pitfalls. One of the main problems is interference from autofluorescent compounds and the incidence of false-positives as exemplified here with a fluorescence polarization (FP)-based assay. Using the scintillation proximity assay as the in-house standard, we assessed several alternatives to radioactive methods, namely, the amplified luminescent proximity homogeneous assay screen (ALPHAScreen, Perkin-Elmer Life Sciences, Boston, MA), enzyme fragment complementation, FP, and nanofluidics-based fluorescence intensity. Data comparing the sensitivity, robustness, relative sensitivity to autofluorescent compounds, enzyme consumption, and relative costs of each assay for one common kinase are presented. Results obtained seem to favor the nanofluidics mobility shift assay as a method of choice, followed by the direct FP approach, using generic high-molecular-weight phosphate group-binders.
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Affiliation(s)
- Dominique Perrin
- Molecular Screening and Cellular Pharmacology Department, Serono Pharmaceutical Research Institute, Geneva, Switzerland.
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12
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Brunecky R, Lee S, Rzepecki PW, Overduin M, Prestwich GD, Kutateladze AG, Kutateladze TG. Investigation of the binding geometry of a peripheral membrane protein. Biochemistry 2006; 44:16064-71. [PMID: 16331966 PMCID: PMC2516348 DOI: 10.1021/bi051127+] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A growing number of modules including FYVE domains target key signaling proteins to membranes through specific recognition of lipid headgroups and hydrophobic insertion into bilayers. Despite the critical role of membrane insertion in the function of these modules, the structural mechanism of membrane docking and penetration remains unclear. In particular, the three-dimensional orientation of the inserted proteins with respect to the membrane surface is difficult to define quantitatively. Here, we determined the geometry of the micelle penetration of the early endosome antigen 1 (EEA1) FYVE domain by obtaining NMR-derived restraints that correlate with the distances between protein backbone amides and spin-labeled probes. The 5- and 14-doxyl-phosphatidylcholine spin-labels were incorporated into dodecylphosphocholine (DPC) micelles, and the reduction of amide signal intensities of the FYVE domain due to paramagnetic relaxation enhancement was measured. The vector of the FYVE domain insertion was estimated relative to the molecular axis by minimizing the paramagnetic restraints obtained in phosphatidylinositol 3-phosphate (PI3P)-enriched micelles containing only DPC or mixed with phosphatidylserine (PS). Additional distance restraints were obtained using a novel spin-label mimetic of PI(3)P that contains a nitroxyl radical near the threitol group of the lipid. Conformational changes indicative of elongation of the membrane insertion loop (MIL) were detected upon micelle interaction, in which the hydrophobic residues of the loop tend to move deeper into the nonpolar core of micelles. The micelle insertion mechanism of the FYVE domain defined in this study is consistent with mutagenesis data and chemical shift perturbations and demonstrates the advantage of using the spin-label NMR approach for investigating the binding geometry by peripheral membrane proteins.
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Affiliation(s)
- Roman Brunecky
- Department of Pharmacology, University of Colorado Health Sciences Center, Aurora, Colorado 80045, USA
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Trost BM, Wrobleski ST, Chisholm JD, Harrington PE, Jung M. Total Synthesis of (+)-Amphidinolide A. Assembly of the Fragments. J Am Chem Soc 2005; 127:13589-97. [PMID: 16190724 DOI: 10.1021/ja0533646] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The structure elucidation of (+)-amphidinolide A, a cytotoxic macrolide, has been accomplished by employing a combination of total synthesis and NMR spectroscopic analysis. Amphidinolide A possesses two skipped 1,4-diene subunits which are accessible by ruthenium-catalyzed alkene-alkyne couplings. Previous total syntheses had revealed that the reported structure was incorrect; therefore, to incorporate maximum flexibility into the synthesis, with the ultimate goal of determining the correct structure, a highly convergent approach was chosen. Furthermore, liberal use was made of catalytic asymmetric transformations to set individual stereocenters. Three different strategies were envisioned for the end game, and due to the highly convergent nature of the synthesis, all three routes disconnect to the same three key intermediates, 5, 6, and 7. Diastereomers of 6 and 7 were easily prepared by modification of the synthetic routes to allow access to multiple diastereomers of 1 for structural determination.
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Affiliation(s)
- Barry M Trost
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA.
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Prestwich GD. Visualization and perturbation of phosphoinositide and phospholipid signaling. Prostaglandins Other Lipid Mediat 2005; 77:168-78. [PMID: 16099401 DOI: 10.1016/j.prostaglandins.2004.09.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2004] [Accepted: 09/14/2004] [Indexed: 10/26/2022]
Abstract
Cells signal through lipids that are produced by phospholipid (PL) and phosphoinositide (PIPn) metabolism involve three enzymatic processes: (i) ester and phosphodiester hydrolysis by phospholipases, (ii) monophosphate hydrolysis by phosphatases, and (iii) phosphorylation of hydroxy groups by kinases. Unregulated enzyme activity correlates with specific pathologies, which are specific targets for therapeutic intervention. A variety of reagents now permit monitoring of in vitro enzyme activity, spatiotemporal changes of intracellular lipid concentrations, and identification of lipid-protein interactions. This minireview summarizes a chemical biology approach that illustrates how chemically synthesized affinity probes can be used to characterize changes in lipid signaling in cellular and molecular biology.
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Affiliation(s)
- Glenn D Prestwich
- Department of Medicinal Chemistry, The University of Utah, 419 Wakara Way, Suite 205, Salt Lake City, UT 84108-1257, USA.
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Abstract
Lipid signaling by phosphoinositides (PIP(n)s) involves an array of proteins with lipid recognition, kinase, phosphatase, and phospholipase functions. Understanding PIP(n) pathway signaling requires identification and characterization of PIP(n)-interacting proteins. Moreover, spatiotemporal localization and physiological function of PIP(n)-protein complexes must be elucidated in cellular and organismal contexts. For protein discovery to functional elucidation, reporter-linked phosphoinositides or tethered PIP(n)s have been essential. The phosphoinositide 3-kinase (PI 3-K) signaling pathway has recently emerged as an important source of potential "druggable" therapeutic targets in human pathophysiology in both academic and pharmaceutical environments. This review summarizes the chemistry of PIP(n) affinity probes and their use in identifying macromolecular targets. The process of target validation will be described, i.e., the use of tethered PIP(n)s in determining PIP(n) selectivity in vitro and in establishing the function of PIP(n)-protein complexes in living cells.
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Affiliation(s)
- Glenn D Prestwich
- Department of Medicinal Chemistry, The University of Utah, 419 Wakara Way, Suite 205, Salt Lake City, UT 84108, USA.
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Trost BM, Harrington PE. Structure Elucidation of (+)-Amphidinolide A by Total Synthesis and NMR Chemical Shift Analysis. J Am Chem Soc 2004; 126:5028-9. [PMID: 15099060 DOI: 10.1021/ja049292k] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structure elucidation of (+)-amphidinolide A, a cytotoxic macrolide, has been accomplished by employing a combination of NMR chemical shift analysis and total synthesis. Using the reported structure as a starting point, a number of diastereomers of amphidinolide A were prepared. The deviations of the chemical shifts of key protons in each isomer relative to the values reported for the isolated material were used to determine the locations of the errors in relative stereochemistry. The spectroscopic data for our proposed structure of (+)-amphidinolide A and the isolated material are in excellent agreement. The key step, a [Cp*Ru(MeCN)3]PF6-catalyzed alkene-alkyne coupling, was used to form the 20-membered ring in the final step of the synthesis.
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Affiliation(s)
- Barry M Trost
- Department of Chemistry, Stanford University, California 93405-5080, USA.
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