74097-24-8Relevant academic research and scientific papers
The synthesis of alisamycin, nisamycin, LL-C10037α and novel epoxyquinol and epoxyquinone analogues of manumycin A
Taylor, Richard J. K.,Alcaraz, Lilian,Kapfer-Eyer, Isabelle,Macdonald, Gregor,Wei, Xudong,Lewis, Norman
, p. 775 - 790 (2007/10/03)
Versatile synthetic routes are described for the preparation of a range of epoxyquinol and epoxyquinone analogues of the antitumour antibiotic manumycin A lacking the lower side chain, and these procedures have also been applied to prepare the bioactive natural product LL-C10037α. The extension of this methodology to provide a general synthetic route to the manumycin family of antibiotics is discussed and exemplified by the first total synthesis of alisamycin and ent-alisamycin. This route includes the novel, stereoselective organometallic addition of the Corey-Wollenberg reagent (E- 2-tributylstannylethenyllithium) to the manumycin nucleus and palladium catalysed Stille coupling technology for the introduction of the polyunsaturated 2-amino-3-hydroxycyclopentenone derived amide. Similar methodology has also been employed to complete the first total synthesis of the antibiotic nisamycin.
Synthesis of (-)-LL-C10037α and related manumycin-type epoxyquinols
Wipf,Kim,Jahn
, p. 1549 - 1561 (2007/10/02)
Starting with N-allyloxycarbonyl-protected 2,5-dimethoxyaniline, hypervalent iodine oxidation protocols and selective enone epoxidation provides the Streptomyces metabolite LL-C10037α in nine steps and 7-10% overall yield. In an asymmetric variant of this strategy, (R,R)-pentane-2,4-diol is used as a chiral acetalization agent. The resulting semiquinone spiroacetal, due to an ortho-acylamino substituent that restricts the 1,3-dioxane ring conformation, undergoes face-selective epoxidation and is further functionalized to give (-)-LL-C10037α in 94% ee. These pathways represent the first syntheses of the highly functionalized mC7N core of the manumycins and have been further extended toward the preparation of analogs for SAR studies of this class of antitumor antibiotics. Manumycins inhibit the farnesylation of Ras-protein by PFTase (protein farnesyltransferase).
An efficient, simple and inexpensive method for the preparation of 1,4-benzoquinone monoketals via anodic oxidation of 1,4-dimethoxybenzenes
Gautier,Lewis,McKillop,Taylor
, p. 2989 - 3008 (2007/10/02)
Anodic oxidation of a series of 1-substituted-2,5-dimethoxybenzenes gives 2-substituted-1,1,4,4-tetramethoxycyclohexa-2,5-dienes in almost quantitative crude yield. Selective monohydrolysis of these bis-ketals is possible in many cases, and gives 3-substi
Anodic Oxidation Products of 2',5'-Dimethoxyacetanilide Derivatives, and Their Application to the Synthesis of Aminoanthraquinones
Russell, Richard A.,Longmore, Robert W.,Warrener, Ronald N.
, p. 1691 - 1704 (2007/10/02)
Anodic oxidation of simple 2',5'-dimethoxyacetanilides proceeds under mildly basic conditions to afford either monomeric or dimeric quinone bisacetals, depending on the structure of the substrate.Similarly, the oxidation of linked derivatives of 2',5'-dimethoxyacetanilides is shown to exhibit a comparable sensitivity, with non-alkylated amides being efficiently converted into bis(quinone bisacetals).The regiospecificity of acetal hydrolysis for both simple and linked quinone bisacetals is shown to be dependent upon the nature of the N-acyl group.The annelation of these hydrolysis products with the anion of 3-cyanophthalide to yield (acylamino)anthraquinones is also reported.
Chemistry of Quinone Derivatives. Quinone Monoketals via Hydrolysis of Electrochemically Derived Quinone Bisketals
Henton, Daniel R.,Anderson, Keith,Manning, Michael J.,Swenton, John S.
, p. 3422 - 3433 (2007/10/02)
The monohydrolysis of nine naphthoquinone bisketals and nine benzoquinone bisketals has been studied.In the acetamido, bromo, methyl, methoxy, and thiomethyl monosubstituted compounds, hydrolysis occurs at the ketal more distant from the substituent.The regiochemistry is nearly exclusive in the naphthoquinone series and is highly selective in the benzoquinone series.For disubstituted benzoquinone and naphthoquinone bisketals, the monohydrolysis is often regiospecific but substituent dependent.The origin of the regioselectivity in the reactions is briefly discussed.
