Regiospecific additions of some simple dienes to haloquinones
作者:Louise Boisvert、Paul Brassard
DOI:10.1016/s0040-4039(00)81953-x
日期:1983.1
Some simple dienes have been shown to react regiospecifically with haloquinones; the adducts can be oxidized without loss of the oxygenated function or aromatized to a variety of natural products and useful intermediates.
Studies on ketene and its derivatives. CIX. Synthesis of naturally occurring anthracene-9,10-diones.
作者:NOBUYA KATAGIRI、TETSUZO KATO、JUN NAKANO
DOI:10.1248/cpb.30.2440
日期:——
The synthesis of naturally occurring anthracene-9, 10-diones (12a-c) from ethyl 2-benzyl-4, 6-dihydroxybenzoates (7a-d), prepared by the reaction of diketene with ethyl 4-aryl-3-oxobutanoates (6a-d), is described. Reaction of diketene with 6a-d in the presence of sodium hydride in tetrahydrofuran gave 7a-d. Treatment of 7a-d with methyl iodide in the presence of potassium carbonate, followed by ethanolic sodium hydroxide, gave 2-benzyl-4, 6-dimethoxybenzoic acids (9a-d). Cyclization of 9a-d with trifluoroacetic acid-trifluoroacetic anhydride gave anthrone derivatives (10a-d) which, without purification, were oxidized with chromium trioxide to give the anthracene-9, 10-diones (11a-d). Selective demethylation of 11a-c with boron tribromide gave 12a-c.
Applications of [4+2] Anionic Annulation and Carbonyl-Ene Reaction in the Synthesis of Anthraquinones, Tetrahydroanthraquinones, and Pyranonaphthoquinones
作者:Shyam Basak、Dipakranjan Mal
DOI:10.1021/acs.joc.7b01987
日期:2017.10.20
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-enereaction (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
investigation of the onion pathogenic fungus Alternariaporri resulted in the isolation of two new phthalides named zinnimide (2) and deprenylzinnimide (8), along with a new bianthraquinone, alterporriol F (10). The structures of the new metabolites were characterised by spectroscopic analysis and chemical degradation. Of the new compounds isolated, alterporriol F was highly cytotoxic towards HeLa and KB
对洋葱病原性真菌Alternaria porri的化学研究导致分离出了两种新的邻苯二甲酸酯,分别称为zinnimide(2)和deprenylzinnimide(8),以及一种新的比蒽醌,Alterporriol F(10)。通过光谱分析和化学降解来表征新代谢物的结构。在分离出的新化合物中,甲三醇F对HeLa和KB细胞具有高度细胞毒性,IC 50值为6.5和7.0 µg mL -1。