60696-52-8Relevant academic research and scientific papers
Four new metabolites of Aspergillus terreus
Kaji,Iwata,Kiriyama,Wakusawa,Miyamoto
, p. 1682 - 1684 (1994)
Four new metabolites (1-4) were isolated from mycelium of Aspergillus terreus IFO 6123 producing asterriquinone (ARQ). The structures of 1 and 2 were shown to be 3,6-bis[1-(1,1-dimethyl-2-propenyl)-1H-indol-3-yl]-furo[3,2-b]furan-2, 5-dione (asterridinone) and 2,5-bis[1,1-dimethyl-2-propenyl)-1H-indol-3-yl]-3-acetoxy-6-hydroxy-2, 5-cyclohexadiene-1,4-dione (ARQ monoacetate), respectively, by the chemical and spectral data. Compounds 3 and 4 were identified with known asterriquinone isomers, 2-[1-(1,1-dimethyl-2-propenyl)-1H-indol-3-yl]-5-[2-(3-methyl-2-butenyl )-1H-indol-3-yl]-3,6-dihydroxy-2,5-cyclohexadiene-1,4-dione (isoARQ) and 2,5-bis[2-(3-methyl-2-butenyl)-1H-indol-3-yl]-3,6-dihydroxy-2,5-cycloh exadiene-1,4-dione (neoARQ), respectively.
Palladium-catalysed N-annulation routes to indoles: The synthesis of indoles with sterically demanding N-substituents, including demethylasterriquinone A1
Fletcher, Anthony J.,Bax, Matthew N.,Willis, Michael C.
, p. 4764 - 4766 (2008/09/17)
Tandem palladium-catalysed aryl and alkenyl C-N bond formation allows the synthesis of a variety of indoles bearing sterically demanding N-substituents, including the natural product demethylasterriquinone A1. The Royal Society of Chemistry.
Total syntheses of demethylasterriquinone B1, an orally active insulin mimetic, and demethylasterriquinone A1.
Pirrung, Michael C,Li, Zhitao,Park, Kaapjoo,Zhu, Jin
, p. 7919 - 7926 (2007/10/03)
Two total syntheses of the unsymmetrical bis-indolylquinone natural product demethylasterriquinone B1 (also known as L-783,281) have been accomplished. The first exploits a known base-promoted condensation of indoles with bromanil, which stops at monoaddition using the sterically hindered 2-isoprenylindole. This permits addition of the second indole, 7-prenylindole, which gives both meta- and para-substituted bis-indolylquinone products. This regiochemical control problem was solved by extension of a method we recently developed for acid-promoted addition of indoles to 2,5-dichlorobenzoquinone. Under our original mineral acid conditions, reaction of 2-isoprenylindole with dichlorobenzoquinone fails, but it succeeds with 3-bromo-2,5-dichlorobenzoquinone using acetic acid as the promoter. The regiochemistry established in such selectively bromine-substituted quinones can be exploited in Stille couplings. As a model system, the synthesis of demethylasterriquinone A1 was accomplished using as the key step a Stille coupling of a 2,5-dibromobenzoquinone with an (N-isoprenylindol-3-yl)tin, producing the para-substituted bis-indolylquinone exclusively. Use of a (7-prenylindole)tin in coupling with a bromo-2,5-dichloro-4-indolylbenzoquinone gives the demethylasterriquinone B1 precursor. The dihaloquinone products of these indole/quinone coupling processes can be hydrolyzed to the dihydroxyquinone natural products. Demethylasterriquinone B1 is of high recent interest as a small molecule insulin mimetic with oral anti-diabetic activity in mice.
METABOLIC PRODUCTS OF ASPERGILLUS TERREUS. V. DEMETHYLATION OF ASTERRIQUINONES
Arai, Kunizo,Shimizu, Sakae,Taguchi, Yasuhisa,Yamamoto, Yuzuru
, p. 991 - 999 (2007/10/02)
Demethylation of asterriquinones (AQ, bisindolyl-dimethoxyl benzoquinones) was investigated in connection with the determination of their structures and studies of their antitumor activity.Usually, the demethylation proceeded smoothly with KOH, but several types of side reactions were observed with acidic reagents.Keywords-demethylation; asterriquinones; Aspergillus terreus; IFO 8835; benzoquinone; indolyl; dimethylallyl
