60512-80-3Relevant academic research and scientific papers
Iridium-Catalyzed C(sp3)?H Addition of Methyl Ethers across Intramolecular Carbon–Carbon Double Bonds Giving 2,3-Dihydrobenzofurans
Ohmura, Toshimichi,Kusaka, Satoshi,Torigoe, Takeru,Suginome, Michinori
supporting information, p. 4448 - 4453 (2019/09/16)
Intramolecular addition of an O-methyl C(sp3)?H bond across a carbon-carbon double bond occurs in the iridium-catalyzed reaction of methyl 2-(propen-2-yl)phenyl ethers. The Ir/(S)-DTBM-SEGPHOS catalyst promotes the reaction efficiently in toluene at 110–135 °C to afford 3,3-dimethyl-2,3-dihydrobenzofurans. Enantioselective C(sp3)?H addition is achieved in the reaction of methyl 2-(1-siloxyethenyl)phenyl ethers, affording enantioenriched 3-hydroxy-2,3-dihydrobenzofuran derivatives with up to 96% ee. (Figure presented.).
Synthesis and antifungal activity of novel sclerotiorin analogues
Lin, Long,Mulholland, Nick,Wu, Qiong-You,Beattie, David,Huang, Shao-Wei,Irwin, Dianne,Clough, John,Gu, Yu-Cheng,Yang, Guang-Fu
experimental part, p. 4480 - 4491 (2012/09/11)
Sclerotiorin 1, first isolated from Penicillium sclerotiorum, has weak antifungal activity and belongs to the azaphilone-type family of natural products. Several series of sclerotiorin analogues were designed and synthesized with the aim of discovering novel fungicides with improved activity. The syntheses involved two key steps, cycloisomerization and then oxidation, and used a simple and efficient Sonogashira cross-coupling reaction to construct the required functionalized precursor. With sclerotiorin as a control, the activities of the newly synthesized analogues were evaluated against seven fungal pathogens, and several promising candidates (compounds 3a1, 3d2, 3e2, 3f2 and 3k2) with greater activity and simpler structures than sclerotiorin were discovered. In addition, preliminary structure-activity relationships were studied, which revealed that not only the chlorine or bromine substituent at the 5-position of the nucleus but also the phenyl group at the 3-position and the substituent pattern on it contributed crucially to the observed antifungal activity. Analogues with a methyl substituent at the 1-position have reduced levels of activity, while those with a free hydroxyl group in place of acetoxy at the quaternary center of the bicyclic ring system retain activity.
New Drug Delivery System for Crossing the Blood Brain Barrier
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Page/Page column 25, (2008/06/13)
New ubiquinol analogs are disclosed, as well as methods of using these compounds to deliver drug moieties to the body.
Synthesis of methoxy-substituted phenols by peracid oxidation of the aromatic ring
Bjorsvik, Hans-Rene,Occhipinti, Giovanni,Gambarotti, Cristian,Cerasino, Leonardo,Jensen, Vidar R.
, p. 7290 - 7296 (2007/10/03)
A novel benign protocol for the preparation of hydroxy-methoxybenzene derivatives is disclosed. By utilizing this protocol, activated aromatic compounds such as l,3-dimethoxy-2-methyl-benzene and 1-(2,6-dimethoxyphenyl) ethanone are smoothly converted to the corresponding monohydroxylated compound. The reaction can be considered to be a normal aromatic electrophilic substitution reaction, and the regioselectivity for the reaction thus follows the similar rules as for electrophilic substitutions. The protocol is composed by benign reagents, namely, hydogenperoxide, acetic acid, and p-toluene sulfonic acid, which lead to the production of ethaneperoxoic acid in situ. The ethaneperoxoic acid operates as the hydroxylating reagent. The hydroxylation reaction is completed within a short period and requires moreover only mild experimental conditions, which make this novel protocol a green, cheap, and rapid process leading to hydroxy-methoxybenzene derivatives. The proposed reaction mechanism is supported by density functional theory and NMR spectroscopy experiments. The mechanism is constituted by two discrete steps: (a) addition of OH+ to the most nucleophilic carbon atom of the aromatic ring, which is the rate-determining step, and (b) the loss of the proton from the aromatic ring.
Access to orthogonal protected phenols - Synthesis of a silylated quinol
Siddiqi, Shahzad A.,Heckrodt, Thilo J.
, p. 328 - 331 (2007/10/03)
Herein we describe the synthesis of t-butyldimethylsilyl protected quinol (9), using an oxidation/reduction sequence to create the desired orthogonality. The title compound acts as a synthetic equivalent for a quinone, required in the total synthesis of E
Indoloquinones, part 7. Total synthesis of the potent lipid peroxidation inhibitor carbazoquinocin C by an intramolecular palladium-catalyzed oxidative coupling of an anilino-1,4-benzoquinone
Kn?lker, Hans-Joachim,Fr?hner, Wolfgang,Reddy, Kethiri R.
, p. 557 - 564 (2007/10/03)
A highly efficient total synthesis of the potent lipid peroxidation inhibitor carbazoquinocin C is presented. The key-step is a palladium(II)-catalyzed oxidative cyclization of an anilino-1,4-benzoquinone to a carbazole-1,4-quinone which proceeds in up to 91% yield. Using this approach the natural product is obtained in four steps and 39% overall yield starting from aniline.
Synthesis of a Diels-Alder precursor for the Elisabethin A skeleton
Heckrodt, Thilo J.,Mulzer, Johann
, p. 1857 - 1866 (2007/10/03)
A synthesis of a precursor 2 for the Elisabethin A skeleton is reported. Containing a masked quinone and a (E,Z)-diene sub-unit, it has the required elements for the envisaged intramolecular Diels-Alder reaction to form the tricyclic system of Elisabethin A. Starting from methylresorcinol, the sequence involves the preparation of an arylacetic acid, which was α-alkylated by a chiral building block. Subsequent HWE reaction and cis-selective Wittig olefination furnished the diene with the desired geometry.
Transition metal complexes in organic synthesis, Part 38. First total synthesis of carbazomycin G and H
Knoelker, Hans-Joachim,Froehner, Wolfgang
, p. 4051 - 4054 (2007/10/03)
The first total synthesis of the carbazole quinol alkaloids carbazomycin G and H has been achieved by a highly convergent synthesis using an iron-mediated construction of the carbazole nucleus as key-step.
The Synthesis of Indan-1-ones and Isocoumarins
Carter, Rachel H.,Garson, Mary J.,Hill, Robert A.,Staunton, James,Sunter, David C.
, p. 471 - 479 (2007/10/02)
A flexible synthetic route leading via indan-1-ones to variously methylated and oxygenated isocoumarins is described.The indanones are prepared by alternative routes involving intramolecular Friedel-Crafts cyclisation of arylpropionic acids or pericyclic ring closure of acrylophenones.The influence of substitution on the rate of the pericyclic reaction is assessed.
