- Synthesis of highly functionalized anthraquinones and evaluation of their antitumor activity
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Highly functionalized anthraquinones which derive from the natural products mensacarcin, islandicin, and chrysophanol have been efficiently synthesized using a Diels-Alder reaction as key step. The introduction of the proposed pharmacophoric side chain unit has been achieved by an addition of an aryllithium species onto different aldehydes. Furthermore, the antitumor activity of these novel compounds has been studied by the in vitro growth inhibition of human lung carcinoma cells of line A549. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
- Tietze, Lutz F.,Gericke, Kersten M.,Schuberth, Ingrid
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- Synthetic Anthracyclinones. 25. An Improved Route to 8-Demethoxyaranciamycinone and Synthesis of the α-L-Daunosamine Glycosides
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An improved regioselective synthesis for the anthracyclinone precursor 12 is reported using a combination of Diels-Alder and Marschalk reactions.The solvolysis of the benzylic bromides 19/20 with water mainly yields the 7,9-trans-diol 8-demethoxyaranciamycinone (22) whereas the treatment with sodium hydroxide affords the 7,9-cis-diol 21.The α-L-daunosamine glycosides 27-30 are prepared and their absolute configurations are determined by 1H NMR spectroscopy.
- Krohn, Karsten,Broser, Erwin
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- ALOECHRYSONE, A DIHYDROANTHRACENONE FROM ALOE BERHANA
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Analysis of the roots of Aloe berhana resulted in the isolation of aloesaponol I, laccaic acid D methyl ester, aloesaponol III, aloesaponarin I, chrysophanol-8-methyl ether, chrysophanol and the new dihydroanthracenone 3,4-dihydro-3,9-dihydroxy-8-methoxy-3-methyl-1(2H)-anthracenone named aloechrysone. Key words: Aloe berhana; Asphodelaceae; roots; leaves; dihydroanthracenones; (R)-aloechrysone; anthraquinones.
- Dagne, Ermias,Casser, Ingrid,Steglich, Wolfgang
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- A new synthesis of Rhein
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A novel synthesis of Rhein (2), the active metabolite of the anti-osteoarthritic drug Diacetyl Rhein (1) has been achieved. Key steps include stereospecific olefination of aldehyde 21 with novel phosphonate 28 and the cylisation of acid 31 to produce anthracene 32.
- Gallagher, Peter T.,Hicks, Terry A.,Lightfoot, Andrew P.,Martin Owton
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- Applications of [4+2] Anionic Annulation and Carbonyl-Ene Reaction in the Synthesis of Anthraquinones, Tetrahydroanthraquinones, and Pyranonaphthoquinones
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Hexa-2,5-dienoates, susceptible to isomerization by acids and bases, are suitable for the [4+2] anionic annulation to give 3-(2-alkenyl)naphthoates in regiospecific manner. When combined with intramolecular carbonyl-ene reaction (ICE), the accessibility of the naphthoates culminates in a new synthesis of anthraquinones and diastereoselective synthesis of tetrahydroanthraquinones. This strategy has also resulted in a 3-step synthesis of dehydroherbarin from a 3-methallylnaphthoate.
- Basak, Shyam,Mal, Dipakranjan
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p. 11035 - 11051
(2017/10/27)
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- Intramolecular aldol-type condensation between side chains of naphthoquinones: Biomimetic synthesis of 1,6- and 1,8-dihydroxyanthraquinones
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Intramolecular condensation of 2-(acetonyl)-3-acyljuglone derivatives under basic conditions gave 1,6- and/or 1,8-dihydroxyanthraquinones depending on the conditions employed. Treatment of 6-[(3-acetyl-5-methoxy-1,4-dioxo-1,4-dihydro-2-naphthyl)methyl]-2,2- dimethyl-4H-1,3-dioxin-4-one with K2CO3 in alcohol brought about the intramolecular Knoevenagel-type reaction to give 3-hydroxy-8-methoxy-1-methyl-9,10-dioxo-9,10-dihydro-anthracene-2- carboxylates in good yields, while the same naphthoquinone gave 4-hydroxy-5-methoxy-9,10-dioxo-9,10-dihydroanthracene-2-acetic acid in good yield by treatment with potassium bis(trimethylsilyl)amide (KHMDS). Chrysophanol, aloe-emodin, aloesaponarin I, and K1115A were prepared in good yields.
- Uno, Hidemitsu,Masumoto, Akane,Honda, Erina,Nagamachi, Yumi,Yamaoka, Youtarou,Ono, Noboru
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p. 3189 - 3197
(2007/10/03)
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- REACTIONS OF KETENE ACETALS-14; THE USE OF SIMPLE MIXED VINYLKETENE ACETALS IN THE ANNULATION OF QUINONES
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α,β- and β,γ-unsaturated esters can be converted by strong base and chlorotrimethylsilane to the corresponding mixed vinylketene acetals which are shown to be particularly useful and generally applicable reagents for the regiospecific annulation of halogenoquinones.The reaction proceeds readily with a variety of substrates including benzoquinones.
- Savard, Jacques,Brassard, Paul
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p. 3455 - 3464
(2007/10/02)
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- Novel Oxidative Transformation: Regiospecific Preparation of Naturally Occurring 1-Hydroxyanthraquinones
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A brief reaction sequence for synthesis of the naturally occurring anthraquinones 1-hydroxyanthraquinone (4a), 1-hydroxy-2-methylanthraquinone (4b), pachybasin (4c), chrysophanol (5a), and rhein (5c) has been developed.
- Hauser, Frank M.,Prasanna, Subbarao
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p. 383 - 384
(2007/10/02)
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- SYNTHETISCHE ANTHRACYCLINONE XVI SYNTHESE HYDROXYLIERTER ANTHRACHINONE DURCH REGIOSELEKTIVE DIELS-ALDER-REAKTION
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Naturally occuring quinones such as 7-methyljuglone, chrysophanol, emodin, helminthosporin, phomarin and physcion were prepared via Diels-Alder reaction and PCC-oxidation of the allylic alcohols obtained from the adducts.
- Krohn, Karsten
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p. 3557 - 3560
(2007/10/02)
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