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Wanat M, Malinska M, Kutner A, Woźniak K. Relation Between Crystal Structures of Precursors and Final Products: Example of Vitamin D Intermediates. Molecules 2020; 25:molecules25081802. [PMID: 32295313 PMCID: PMC7221991 DOI: 10.3390/molecules25081802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 04/03/2020] [Accepted: 04/10/2020] [Indexed: 01/02/2023] Open
Abstract
In this paper, we proved that the solid-state structure of vitamin D analog is well represented by the structures of its structural fragments. This is important in predicting the biological activity of vitamin D analogs that are not available in the solid form. The previously published crystal structure of advanced vitamin D intermediate provided additional insights into vitamin D properties. A similar analysis based on simple vitamin D intermediate analogues showed that precursors crystallized in the space groups typical for vitamins D; geometrical parameters were related to the corresponding parameters in the vitamin D analogues; and crystal structures of the basic intermediates and their final products contained similar intermolecular interactions, essential for the infinite hydrogen bond motif observed in the vitamin D analogues. The energy of these interactions is related as shown by theoretical calculations, that is, energy frameworks analysis. Moreover, analysis of the hydrogen bonds motifs revealed a relation between these motifs and the absolute configuration of basic intermediates as well as the space orientation of the exocyclic methylene group in the final structures.
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Affiliation(s)
- Monika Wanat
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, 101 Żwirki i Wigury, 02-089 Warszawa, Poland; (M.W.); (M.M.)
- College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences (MISMaP), University of Warsaw, 2C Stefana Banacha, 02-097 Warszawa, Poland
| | - Maura Malinska
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, 101 Żwirki i Wigury, 02-089 Warszawa, Poland; (M.W.); (M.M.)
| | - Andrzej Kutner
- Faculty of Pharmacy, Department of Bioanalysis and Drug Analysis, Medical University of Warsaw, 1 Stefana Banacha, 02-097 Warszawa, Poland;
| | - Krzysztof Woźniak
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, 101 Żwirki i Wigury, 02-089 Warszawa, Poland; (M.W.); (M.M.)
- Correspondence: ; Tel.: +48-22-5526-391
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2
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O'Connell N, O'Callaghan Y, O'Brien N, Maguire A, McCarthy F. Synthetic routes to campesterol and dihydrobrassicasterol: a first reported synthesis of the key phytosterol dihydrobrassicasterol. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.04.060] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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3
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Vávra J, Severa L, Švec P, Císařová I, Koval D, Sázelová P, Kašička V, Teplý F. Preferential Crystallization of a Helicene-Viologen Hybrid - An Efficient Method to Resolve [5]Helquat Enantiomers on a 20 g Scale. European J Org Chem 2011. [DOI: 10.1002/ejoc.201101367] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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4
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Izgu EC, Burns AC, Hoye TR. Access to functionalized steroid side chains via modified Julia olefination. Org Lett 2011; 13:703-5. [PMID: 21244047 DOI: 10.1021/ol102936z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Various functionalized steroidal side chains were conveniently accessed by a modified Julia olefination strategy using a common sulfone donor and an appropriate α-branched aldehyde acceptor. For the coupling of these hindered classes of reaction partners (and in contrast to typically observed trends), the benzothiazolyl(BT)-sulfone anion gave superior outcomes compared to the phenyltetrazolyl(PT)-sulfone anion.
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Affiliation(s)
- Enver Cagri Izgu
- Department of Chemistry, 207 Pleasant Street, SE, University of Minnesota, Minneapolis, Minnesota 55455, USA
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5
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Antonchick AV, Zhabinskii VN, Khripach VA. Synthesis of sterols oxygenated in the terminal fragment of their side chains. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2008. [DOI: 10.1134/s1068162008040018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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6
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Khripach VA, Zhabinskiĭ VN, Antonchik AV, Antonchik AP. [Synthesis of (24S)-hydroxy- and (24S)-24,25-epoxycholesterol analogues, potential agonists of nuclear LXR receptors]. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2006; 32:651-9. [PMID: 17180916 DOI: 10.1134/s1068162006060124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A new approach to the synthesis of a series of isomeric 24-hydroxy- and 24,25-epoxysteroids starting from lithocholic acid was proposed. Sharpless asymmetric hydroxylation of intermediate delta24-olefines was used as a reaction determining the stereochemistry of target compounds. The resulting derivatives are potential agonists of nuclear receptors LXRalpha and LXRbeta and are potentially useful in the structure-function studies.
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Spencer TA, Wang P, Popovici-Müller JV, Peltan ID, Fielding PE, Fielding CJ. Preparation and biochemical evaluation of fluorenone-containing lipid analogs. Bioorg Med Chem Lett 2006; 16:3000-4. [PMID: 16529926 DOI: 10.1016/j.bmcl.2006.02.061] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2006] [Revised: 02/21/2006] [Accepted: 02/21/2006] [Indexed: 10/24/2022]
Abstract
Syntheses are described of fatty acid analogs 5 and 6, and cholesterol (2) analogs 7 and 8 containing fluorenone groups, which are both photoactivable and fluorescent. The potential of the analogs of 2 as biochemical research tools has been demonstrated by the findings that 7 and 8 can replace 2 in apolipoprotein A-I-induced cellular efflux of 2 and that fluorescence is easily visible at the surface of smooth muscle cells equilibrated with 8.
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Affiliation(s)
- Thomas A Spencer
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA.
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8
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Drozdov FV, Timofeev VP, Misharin AI. A simple synthesis of 3β-acetoxy-20-oxomethylpregn-5-ene and 3β-acetoxy-20-hydroxymethylpregn-5-ene. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2006; 32:107-9. [PMID: 16523729 DOI: 10.1134/s1068162006010122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
3beta-Acetoxy-20-oxomethylpregn-5-ene and 3beta-acetoxy-20-hydroxymethylpregn-5-ene were synthesized from (22R,23R)-sitost-5-ene-3beta,22,23-triol in 66% overall yields.
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Shenoy SD, Spencer TA, Mercer-Haines NA, Alipour M, Gargano MD, Runge-Morris M, Kocarek TA. CYP3A induction by liver x receptor ligands in primary cultured rat and mouse hepatocytes is mediated by the pregnane X receptor. Drug Metab Dispos 2004; 32:66-71. [PMID: 14709622 DOI: 10.1124/dmd.32.1.66] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The effects of oxysterol and drug ligands of the liver X receptor (LXR) on cytochrome P450 expression were evaluated in primary cultured rodent hepatocytes. Treatment of rat hepatocyte cultures with either 25-hydroxycholesterol or 24(S),25-epoxycholesterol (10(-5) to 5 x 10(-5) M) produced concentration-dependent elevations in CYP3A mRNA and immunoreactive protein levels but did not increase the amounts of CYP1A1, CYP2B, or CYP4A gene products. The effects of 24(S),25-epoxycholesterol on CYP3A content were much greater than were those of 25-hydroxycholesterol, consistent with the relative abilities of these sterols to bind and activate LXR. To understand the mechanistic basis of these observations, experiments were performed using primary cultured hepatocytes prepared from LXRalpha/beta- or pregnane X receptor (PXR)-null mice. CYP3A mRNA levels were increased after treatment with 24(S),25-epoxycholesterol in both wild-type and LXR-null mouse hepatocytes. In contrast, neither 24(S),25-epoxycholesterol nor either of two additional potent LXR ligands, 22(R)-hydroxycholesterol and N-(2,2,2-trifluoroethyl)-N-[4-[2,2,2-trifluoro-1-hydroxy-1(trifluoromethyl)ethyl-]phenyl]-benzenesulfonamide (T0901317), altered CYP3A mRNA levels in hepatocytes prepared from PXR-null mice, although these agents induced CYP3A mRNA content in wild-type cultures. As evidence that the LXR ligands also activated PXR in rat hepatocytes, cotransfection of primary cultures with a dominant negative PXR abolished reporter gene induction after treatment with any of the test agents. These results indicate that selected LXR ligands are capable of activating PXR, probably as a defensive measure to prevent the accumulation of these potentially toxic endogenous molecules.
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MESH Headings
- Animals
- Anticholesteremic Agents/pharmacology
- Aryl Hydrocarbon Hydroxylases/biosynthesis
- Blotting, Northern
- Blotting, Western
- Cells, Cultured
- Cytochrome P-450 CYP3A
- DNA-Binding Proteins
- Enzyme Induction/drug effects
- Gene Expression Regulation/drug effects
- Genes, Reporter/genetics
- Hepatocytes/drug effects
- Hepatocytes/enzymology
- Hydroxycholesterols/metabolism
- Ligands
- Liver X Receptors
- Male
- Mice
- Mice, Inbred C57BL
- Orphan Nuclear Receptors
- Oxidoreductases, N-Demethylating/biosynthesis
- Pregnane X Receptor
- Rats
- Rats, Sprague-Dawley
- Receptors, Cytoplasmic and Nuclear/drug effects
- Receptors, Cytoplasmic and Nuclear/metabolism
- Receptors, Steroid/drug effects
- Transcription Factors/metabolism
- Transcriptional Activation
- Transfection
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Affiliation(s)
- Sarita D Shenoy
- Institute of Environmental Health Sciences, 2727 Second Avenue, Room 4000, Detroit, MI 48201, USA
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Spencer TA, Wang P, Li D, Russel JS, Blank DH, Huuskonen J, Fielding PE, Fielding CJ. Benzophenone-containing cholesterol surrogates: synthesis and biological evaluation. J Lipid Res 2004; 45:1510-8. [PMID: 15175357 DOI: 10.1194/jlr.m400081-jlr200] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Eight analogs of cholesterol (1) containing a benzophenone group have been synthesized as prospective photoaffinity labels for studies in cellular sterol efflux and HDL formation. Six of these compounds (4-9) have the photophore replacing different portions of the cholesterol alkyl side chain, and two (10 and 11) have it attached via nitrogen at carbon 3. The suitability of these analogs as cholesterol surrogates was determined by examining their ability to replace [3H]1 in fibroblasts preequilibrated with [3H]1. All eight analogs were effective in replacing natural 1 in competition with [3H]1 for apolipoprotein A-I-induced efflux. These are the first compounds shown to replace cholesterol successfully in a complex pathway of multiple intracellular steps. The results suggest an unexpected tolerance of biological membranes regarding the incorporation of sterols of differing chemical structure.
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Affiliation(s)
- Thomas A Spencer
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA.
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11
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Shenoy SD, Spencer TA, Mercer-Haines NA, Abdolalipour M, Wurster WL, Runge-Morris M, Kocarek TA. Induction of CYP3A by 2,3-Oxidosqualene:Lanosterol Cyclase Inhibitors Is Mediated by an Endogenous Squalene Metabolite in Primary Cultured Rat Hepatocytes. Mol Pharmacol 2004; 65:1302-12. [PMID: 15102959 DOI: 10.1124/mol.65.5.1302] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The effects of inhibitors of 2,3-oxidosqualene:lanosterol cyclase (cyclase) on cytochrome P450 expression were investigated in primary cultures of rat hepatocytes. Treatment of hepatocyte cultures for 24 h with either of the inhibitors [4'-(6-allyl-methyl-amino-hexyloxy)-2'-fluoro-phenyl]-(4-bromophenyl)-methanone fumarate (Ro 48-8071) or trans-N-(4-chlorobenzoyl)-N-methyl-(4-dimethylaminomethylphenyl)-cyclohexylamine (BIBX 79) selectively increased CYP3A mRNA and immunoreactive protein contents, with maximal accumulations occurring at 3 x 10(-5) M Ro 48-8071 and 10(-4) M BIBX 79. The abilities of Ro 48-8071, BIBX 79, and 3beta-(2-diethylaminoethoxy)androst-5-en-17-one.HCl (U18666A) to induce murine CYP3A were abolished in hepatocyte cultures prepared from pregnane X receptor (PXR)-null mice, and cotransfection of primary cultured rat hepatocytes with a dominant-negative PXR prevented cyclase inhibitor-inducible luciferase expression from a PXR-responsive reporter plasmid. Cyclase inhibitor-mediated CYP3A mRNA induction was eliminated when primary cultured rat hepatocytes were cotreated with any of the following agents that inhibit steps upstream of cyclase in the cholesterol biosynthetic pathway: squalestatin 1 (squalene synthase inhibitor), (E)N-ethyl-N-(6,6-dimethyl-2-hepten-4-ynyl)-3-[(3,3'-bithiophen-5-yl)methoxy]benzenemethanamine (NB-598, squalene monooxygenase inhibitor), or pravastatin (HMG-CoA reductase inhibitor). Ro 48-8071-inducible CYP3A mRNA expression was restored when pravastatin-treated cultures were incubated with medium containing mevalonate. The concentration-dependence of Ro 48-8071-mediated CYP3A mRNA induction corresponded to the cellular contents of metabolically labeled squalene 2,3-oxide and squalene 2,3:22,23-dioxide, but not 24(S),25-epoxycholesterol. These results indicate that cyclase inhibitors are capable of inducing CYP3A expression in primary cultured rat and mouse hepatocytes and that the effect is mediated as a consequence of cyclase blockade through the evoked accumulation of one or more squalene metabolites that activate the PXR.
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Affiliation(s)
- Sarita D Shenoy
- Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan 48201, USA
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Williams S, Bledsoe RK, Collins JL, Boggs S, Lambert MH, Miller AB, Moore J, McKee DD, Moore L, Nichols J, Parks D, Watson M, Wisely B, Willson TM. X-ray crystal structure of the liver X receptor beta ligand binding domain: regulation by a histidine-tryptophan switch. J Biol Chem 2003; 278:27138-43. [PMID: 12736258 DOI: 10.1074/jbc.m302260200] [Citation(s) in RCA: 176] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The x-ray crystal structures of the human liver X receptor beta ligand binding domain complexed to sterol and nonsterol agonists revealed a perpendicular histidinetryptophan switch that holds the receptor in its active conformation. Hydrogen bonding interactions with the ligand act to position the His-435 imidazole ring against the Trp-457 indole ring, allowing an electrostatic interaction that holds the AF2 helix in the active position. The neutral oxysterol 24(S),25-epoxycholesterol accepts a hydrogen bond from His-435 that positions the imidazole ring of the histidine above the pyrrole ring of the tryptophan. In contrast, the acidic T0901317 hydroxyl group makes a shorter hydrogen bond with His-435 that pulls the imidazole over the electron-rich benzene ring of the tryptophan, possibly strengthening the electrostatic interaction. Point mutagenesis of Trp-457 supports the observation that the ligand-histidine-tryptophan coupling is different between the two ligands. The lipophilic liver X receptor ligand-binding pocket is larger than the corresponding steroid hormone receptors, which allows T0901317 to adopt two distinct conformations. These results provide a molecular basis for liver X receptor activation by a wide range of endogenous neutral and acidic ligands.
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Affiliation(s)
- Shawn Williams
- GlaxoSmithKline, Discovery Research, Research Triangle Park, NC 27709, USA.
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13
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Zhang Y, Yu C, Liu J, Spencer TA, Chang CCY, Chang TY. Cholesterol is superior to 7-ketocholesterol or 7 alpha-hydroxycholesterol as an allosteric activator for acyl-coenzyme A:cholesterol acyltransferase 1. J Biol Chem 2003; 278:11642-7. [PMID: 12533546 DOI: 10.1074/jbc.m211559200] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We compared the abilities of cholesterol versus various oxysterols as substrate and/or as activator for the enzyme acyl-coenzyme A:cholesterol acyltransferase (ACAT), by monitoring the activity of purified human ACAT1 in response to sterols solubilized in mixed micelles or in reconstituted vesicles. The results showed that 5 alpha,6 alpha-epoxycholesterol and 7 alpha-hydroxycholesterol are comparable with cholesterol as the favored substrates, whereas 7-ketocholesterol, 7 beta-hydroxycholesterol, 5 beta,6 beta-epoxycholesterol, and 24(S),25-epoxycholesterol are very poor substrates for the enzyme. We then tested the ability of 7-ketocholesterol as an activator when cholesterol was measured as the substrate, and vice versa. When cholesterol was measured as the substrate, the addition of 7-ketocholesterol could not activate the enzyme. In contrast, when 7-ketocholesterol was measured as the substrate, the addition of cholesterol significantly activated the enzyme and changed the shape of the substrate saturation curve from sigmoidal to essentially hyperbolic. Additional results show that, as an activator, cholesterol is much better than all the oxysterols tested. These results suggest that ACAT1 contains two types of sterol binding sites; the structural requirement for the ACAT activator site is more stringent than it is for the ACAT substrate site. Upon activation by cholesterol, ACAT1 becomes promiscuous toward various sterols as its substrate.
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Affiliation(s)
- Yi Zhang
- Department of Biochemistry, Dartmouth Medical School, Hanover, New Hampshire 03755, USA
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15
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Kurek-Tyrlik A, Marczak S, Michalak K, Wicha J, Zarecki A. Reaction of arylsulfonylhydrazones of aldehydes with alpha-magnesio sulfones. A novel olefin synthesis. J Org Chem 2001; 66:6994-7001. [PMID: 11597219 DOI: 10.1021/jo015699l] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Reactions of representative tosylhydrazones of aldehydes and ketones with alpha-metalated sulfones were examined in order to develop a practical olefination method. Treatment of aldehyde tosylhydrazone 2 with an excess of alpha-lithiated methyl phenyl or dimethyl sulfones yielded 3a. The reaction of 2 with sterically unhindered lithiated alkyl sulfones gave mixtures of the respective olefination products 3b-d along with the Shapiro fragmentation product 4. Sterically hindered lithiated sulfones afforded Shapiro products exclusively. In contrast, aldehyde tosylhydrazones 2 or 6 in reactions with a variety of alpha-magnesio primary or secondary alkyl sulfones gave olefination products 3a-j and 7a-c in high yields (Tables 1 and 2). beta-Branched alkyl sulfones afforded predominantly (E)-alkenes, whereas unhindered primary sulfones gave mixtures of (E)- and (Z)-alkenes with low selectivity. Reaction of the 2,4,6-triisopropylbenzenesulfonylhydrazone (trisylhydrazone) of cyclodecanone 11c with alpha-magnesio methyl phenyl sulfone afforded the methylidene derivative 12a contaminated with the Shapiro product 13. Tosylhydrazone 2 resisted reaction with i-PrMgCl and gave only a small amount of the addition product in reaction with Bu(2)Mg. Some mechanistic aspects of the reaction of tosylhydrazones with organomagnesium compounds are discussed.
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Affiliation(s)
- A Kurek-Tyrlik
- Institute of Organic Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44, 01-224 Warsaw, Poland
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Zhang Z, Li D, Blanchard DE, Lear SR, Erickson SK, Spencer TA. Key regulatory oxysterols in liver: analysis as Δ4-3-ketone derivatives by HPLC and response to physiological perturbations. J Lipid Res 2001. [DOI: 10.1016/s0022-2275(20)31174-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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17
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Spencer TA, Li D, Russel JS, Collins JL, Bledsoe RK, Consler TG, Moore LB, Galardi CM, McKee DD, Moore JT, Watson MA, Parks DJ, Lambert MH, Willson TM. Pharmacophore analysis of the nuclear oxysterol receptor LXRalpha. J Med Chem 2001; 44:886-97. [PMID: 11300870 DOI: 10.1021/jm0004749] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A cell-free assay was developed for the orphan nuclear receptor LXRalpha that measures the ligand-dependent recruitment of a peptide from the steroid receptor coactivator 1 (SRC1) to the nuclear receptor. Using this ligand-sensing assay (LiSA), the structural requirements for activation of the receptor by oxysterols and related compounds were studied. The minimal pharmacophore for receptor activation was shown to be a sterol with a hydrogen bond acceptor at C24. 24(S),25-Epoxycholesterol (1), which meets this criterion, is among the most efficacious of the oxysterols and is an attractive candidate as the LXRalpha natural hormone. Cholenic acid dimethylamide (14) showed increased efficacy compared to 1, whereas the unnatural oxysterol 22(S)-hydroxycholesterol (4) was shown to be an antagonist of 1 in the LiSA. The structural requirements for SRC1 recruitment in the LiSA correlated with the transcriptional activity of compounds in a cell-based reporter assay employing LXRalpha-GAL4 chimeric receptors. Site-directed mutagenesis identified Trp(443) as an amino acid critical for activation of LXRalpha by oxysterol ligands. This information was combined with the structure-activity relationship developed from the LiSA to develop a 3D homology model of LXRalpha. This model may aid the design of synthetic drugs targeted at this transcriptional regulator of cholesterol homeostasis.
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Affiliation(s)
- T A Spencer
- Dartmouth College, Hanover, New Hampshire 03755, USA
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