- Total synthesis of dihydrolysergic acid and dihydrolysergol: development of a divergent synthetic strategy applicable to rapid assembly of D-ring analogs
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Abstract The total syntheses of dihydrolysergic acid and dihydrolysergol are detailed based on a Pd(0)-catalyzed intramolecular Larock indole cyclization for the preparation of the embedded tricyclic indole (ABC ring system) and a subsequent powerful inverse electron demand Diels-Alder reaction of 5-carbomethoxy-1,2,3-triazine with a ketone-derived enamine for the introduction of a functionalized pyridine, serving as the precursor for a remarkably diastereoselective reduction to the N-methylpiperidine D-ring. By design, the use of the same ketone-derived enamine and a set of related complementary heterocyclic azadiene [4+2] cycloaddition reactions permitted the late stage divergent preparation of a series of alternative heterocyclic derivatives not readily accessible by more conventional approaches.
- Lee, Kiyoun,Poudel, Yam B.,Glinkerman, Christopher M.,Boger, Dale L.
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p. 5897 - 5905
(2015/08/03)
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- ERGOLINE DERIVATIVES AS DOPAMINE RECEPTOR MODULATORS
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The invention provides compounds of formula (I) wherein R1-R4 have any of the values defined in the specification, and salts thereof. The compounds are useful as dopamine receptor modulators for the treatment of diseases where modulation of dopamine receptors is implicated (e.g. sexual dysfunction, prolactinoma, Parkinson's disease, and Cushings disease).
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- Synthesis of novel analogs of cabergoline: Improving cardiovascular safety by removing 5-HT2B receptor agonism
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The dopamine agonist cabergoline has been used to treat prolactinomas, Parkinson's disease, Cushing's disease, and sexual dysfunction. However, its clinical use was severely curtailed when it was found that patients taking cabergoline had an increased risk of developing cardiac-valve regurgitation. This potentially life-threatening condition has been associated with drugs, such as cabergoline, that are 5-HT2B receptor agonists. We prepared analogs of cabergoline and have identified several that have limited or no agonism at the 5-HT2B receptor.
- Dosa, Peter I.,Ward, Tim,Walters, Michael A.,Kim, Suck Won
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p. 254 - 258
(2013/04/10)
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- Synthesis of European pharmacopoeial impurities A, B, C, and D of cabergoline
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For the use of analytics, European pharmacopoeial impurities A, B, C, and D of cabergoline were synthesized. Ergocryptine was chosen as a starting material and synthesis was accomplished via two approaches, different in length and stereochemical outcome. A longer, indirect approach was realized through otherwise problematic oxidations of the 9,10-dihidrolysergol derivative, to the corresponding aldehyde and carboxylic acid. This was achieved by the use of activated DMSO and a Pinnick oxidation sequence. All four synthesized impurities are used as analytical standards in cabergoline manufacturing processes.
- Wagger, Jernej,Pozes, Aljaz,Pozgan, Franc
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p. 23146 - 23156
(2013/11/19)
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- Ergoline derivatives as highly potent and selective antagonists at the somatostatin sst1 receptor
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Non-peptidic compounds containing the octahydro-indolo[4,3-fg]quinoline (ergoline) structural element have been optimized into derivatives with high affinity (pKd r sst1 > 9) and selectivity (>1000-fold for h sst1 over h sst2-h sst5) for the somatostatin sst1 receptor. In functional assays, these ergolines act as antagonists at human recombinant sst1 receptors. Pharmacokinetic studies in rodents reveal good oral bioavailability and brain penetration for some of these compounds.
- Troxler, Thomas,Enz, Albert,Hoyer, Daniel,Langenegger, Daniel,Neumann, Peter,Pfaeffli, Paul,Schoeffter, Philippe,Hurth, Konstanze
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p. 979 - 982
(2008/09/18)
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- Studies on oxidation of ergot alkaloids: oxidation and desaturation of dihydrolysergol-stereochemical requirements
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A new method for the oxidation of ergoline alcohols to aldehydes was found (TFFA-DMSO, -78 °C, then DIPEA). Structural features of ergolines required for successful C7-C8 double bond introduction via Polonovski-Potier reaction of respective 6-N-oxides were defined and experimentally confirmed: (i) the presence of electron-withdrawing group at C-8; (ii) trans-diaxial orientation of N6-O and C7-H bonds (both requirements are fulfilled for dihydrolyserg-17-al and its 2,4-dinitrophenyl hydrazone prepared in this work).
- Ga?ák, Radek,K?en, Vladimír,Sedmera, Petr,Passarella, Daniele,Novotná, Michaela,Danieli, Bruno
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p. 10466 - 10478
(2008/03/13)
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- Serotonergic ergoline derivatives
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Novel classes of 13- and 14-tertbutyl-ergoline derivatives were prepared, and characterised in vitro for their affinity for adrenergic, dopaminergic and serotonergic binding sites. This study particularly examines the importance of the presence and the position of the tert-butyl group in conferring either significant 5-HT(1A) or 5-HT2 affinity and selectivity respectively.
- Mantegani, Sergio,Brambilla, Enzo,Caccia, Carla,Damiani, Gabriele,Fornaretto, Maria Gioia,McArthur, Robert A.,Varasi, Mario
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p. 1117 - 1122
(2007/10/03)
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- THERMAL DECOMPOSITION OF DIHYDROERGOCRISTINE METHANESULPHONATE
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By thermal decomposition of dihydroergocristine methanesulfonate (1a*CH3SO3H) are formed dihydrolysergyldehydrovaline methyl ester (2), dihydrolysergyldehydrovaline azlactone (3c), dihydrolysergic acid (3a), dihydrolysergamide (3b), S-phenylalanyl-S-proline lactam (4a) and S-phenylalanyl-R-proline lactam (4b).
- Rucman, Rudolf,Stanovnik, Branko
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p. 2229 - 2232
(2007/10/02)
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