- Regiospecific synthesis of bikaverin
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A regiospecific synthesis of bikaverin (1) is described starting from methyl 2-hydroxy-4-methoxy-6-methyl benzoate (2) and 2-chloro-5,7-dimethoxy-1,4-naphthoquinone (4).
- Deshpande,Khan,Ayyangar
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p. 2677 - 2682
(2007/10/02)
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- New total synthesis of bikaverin
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On the basis of non-catalysed thermal condensation of a Mannich based with a phenol, followed by dehydration to an o.quinonic chromene further isomerized to a p.quinonic one, the synthesis of bikaverin 7 has been achieved via a six-step route involving selective dealkylation of bikaverin-dimethylether 6.
- Bekaert, Alain,Andrieux, Jean,Plat, Michel
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p. 2805 - 2806
(2007/10/02)
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- CONVENIENT SYNTHESES OF THE NATURALLY OCCURRING BENZOXANTHEN-12-ONE BIKAVERIN. X-RAY CRYSTALLOGRAPHIC CONFIRMATION OF THE PRODUCT REGIOCHEMISTRY
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The synthesis of bikaverin (6,11-dihydroxy-3,8-dimethoxy-1-methylbenzoxanthene-7,10,12-trione) (1) by two related routes is reported.Key steps include the formation of 1,2,4,5,8-pentamethoxynaphthalene (4) in good yield and its regiospecific acylation
- Koning, Charles B.,Giles, Robin G.F.,Engelhardt, Lutz M.,White, Allan H.
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p. 3209 - 3216
(2007/10/02)
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- A Synthesis of Bikaverin (7,12-Dihydro-6,11-dihydroxy-3,8-dimethoxy-1-methyl-10H-benzoxanthene-7,10,12-trione) and some Related Benzoxanthones and Quinones
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Bikaverin, a biologically interesting fungal pigment with the highly oxidised benzoxanthone structure (1), has been synthesized in two steps from 2-hydroxy-4-methoxy-6-methylacetophenone (6f) and dimethyl 3,5-dimethoxyhomophthalate (7f).The synthesis invo
- Kjaer, Dana,Kjaer, Anders,Risbjerg, Elisabeth
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p. 2815 - 2820
(2007/10/02)
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- Synthesis of Bikaverin
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The total synthesis of bikaverin (1b) is described, from everninic acid (5) and 3,5-dihydrobenzoic acid (6).Dieckmann condensation of methyl 2-acetyl-3,5-bis(benzyloxy)phenylacetate (14), synthesised from (6), followed by treatment with protected everninic acid chloride (9) gave 1,3-bisbenzyloxy-6,8-bis(2-benzyloxy-4-methoxy-6-methylbenzyloxy)naphthalene (16).Photoinduced Fries rearrangement of (16) afforded 1,3-bis(benzyloxy)-7-(2-benzyloxy-4-methoxy-6-methylbenzoyl)-6-(2-benzyloxy-4-methoxy-6-methylbenzoyloxy)-8-hydroxynaphthalene (23).Ring closure of (23) with tetramethylammonium hydroxide in pyridine gave the angular benzoxanthene, 1,3-bis(benzyloxy-6-hydroxy)-10-methoxy-8-methylbenzoxanthen-7-one (25), which was oxidized with potassium dichromate to give the orthoquinone, 1,3-bis(benzyloxy)-10-methoxy-8-methylbenzoxanthen-5,6,7-trione (28).By a novel type of rearrangement, (28) was transformed into the linear benzoxanthen, 8,10-bis(benzyloxy)-3-methoxy-1-methylbenzoxanthen-6,11,12-trione (29) by treatment with silica gel.Oxidation and debenzylation of (29) with manganese dioxide in concentrated H2SO4 gave norbikaverin (1a).
- Katagiri, Nobuya,Nakano, Jun,Kato, Tetsuzo
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p. 2710 - 2716
(2007/10/02)
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