22080-97-3Relevant academic research and scientific papers
Oxygen-Free Regioselective Biocatalytic Demethylation of Methyl-phenyl Ethers via Methyltransfer Employing Veratrol- O-demethylase
Grimm, Christopher,Lazzarotto, Mattia,Pompei, Simona,Schichler, Johanna,Richter, Nina,Farnberger, Judith E.,Fuchs, Michael,Kroutil, Wolfgang
, p. 10375 - 10380 (2020/10/02)
The cleavage of aryl methyl ethers is a common reaction in chemistry requiring rather harsh conditions; consequently, it is prone to undesired reactions and lacks regioselectivity. Nevertheless, O-demethylation of aryl methyl ethers is a tool to valorize natural and pharmaceutical compounds by deprotecting reactive hydroxyl moieties. Various oxidative enzymes are known to catalyze this reaction at the expense of molecular oxygen, which may lead in the case of phenols/catechols to undesired side reactions (e.g., oxidation, polymerization). Here an oxygen-independent demethylation via methyl transfer is presented employing a cobalamin-dependent veratrol-O-demethylase (vdmB). The biocatalytic demethylation transforms a variety of aryl methyl ethers with two functional methoxy moieties either in 1,2-position or in 1,3-position. Biocatalytic reactions enabled, for instance, the regioselective monodemethylation of substituted 3,4-dimethoxy phenol as well as the monodemethylation of 1,3,5-trimethoxybenzene. The methyltransferase vdmB was also successfully applied for the regioselective demethylation of natural compounds such as papaverine and rac-yatein. The approach presented here represents an alternative to chemical and enzymatic demethylation concepts and allows performing regioselective demethylation in the absence of oxygen under mild conditions, representing a valuable extension of the synthetic repertoire to modify pharmaceuticals and diversify natural products.
Selective oxidative homo-and cross-coupling of phenols with aerobic catalysts
Lee, Young Eun,Cao, Trung,Torruellas, Carilyn,Kozlowski, Marisa C.
supporting information, p. 6782 - 6785 (2014/06/09)
Simple catalysts that use atom-economical oxygen as the terminal oxidant to accomplish selective ortho-ortho, ortho-para, or para-para homo-couplings of phenols are described. In addition, chromium salen catalysts have been discovered as uniquely effective in the cross-coupling of different phenols with high chemo-and regioselectivity.
PDE10 INHIBITORS AND RELATED COMPOSITIONS AND METHODS
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, (2011/10/04)
Compounds that inhibit PDE10 are disclosed that have utility in the treatment of a variety of conditions, including (but not limited to) psychotic, anxiety, movement disorders and/or neurological disorders such as Parkinson's disease, Huntington's disease, Alzheimer's disease, encephalitis, phobias, epilepsy, aphasia, Bell's palsy, cerebral palsy, sleep disorders, pain, Tourette's syndrome, schizophrenia, delusional disorders, drug-induced psychosis and panic and obsessive-compulsive disorders. Pharmaceutically acceptable salts, stereoisomers, solvates and prodrugs of the compounds are also provided. Also disclosed are compositions containing a compound in combination with a pharmaceutically acceptable carrier, as well as methods relating to the use thereof for inhibiting PDE10 in a warm-blooded animal in need of the same.
Direct oxidative heck cyclizations: Intramolecular Fujiwara-Moritani arylations for the synthesis of functionalized benzofurans and dihydrobenzofurans
Zhang, Haiming,Ferreira, Eric M.,Stoltz, Brian M.
, p. 6144 - 6148 (2007/10/03)
No extra functionalization step is required for palladium(II)-catalyzed oxidative carbocyclizations like that shown, which provide highly substituted benzofuran and dihydrobenzofuran derivatives by net dehydrogenation. The mechanism is similar to that of Heck cyclizations. Products containing quaternary carbon stereocenters can be obtained in diastereomerically pure form.
Trimethoxyphenyl Compounds, XI. Constituents of Hagenia abyssinica, 2: Synthesis of Phloracylophenones Containing One Phloroglucinol Unit
Schiemenz, Guenter Paulus,Behrens, Heinz,Ebert, Claus Peter,Maienschein, Konrad,Schroeder, Jens-Michael
, p. 681 - 692 (2007/10/02)
For the Koso constituents K6 and K8, we previously proposed the structures 1a, b and 2a, b.These assignments have been confirmed by synthesis. - Keywords: Flores koso, Revised Structure, Synthesis of Phloroglucinols
Naturally Occurring Dibenzofurans. Part 4. Synthesis of Dibenzofurandiols by Annelation of Benzofurans
Carvalho, Christopher F.,Sargent, Melvyn V.
, p. 1605 - 1612 (2007/10/02)
Methyl 3-acetylbenzofuran-2-ylacetate (8) undergoes C-methylation affording methyl 2-(3-acetylbenzofuran-2-yl)propionate (13).These compounds and similar oxo esters undergo ready cyclization to dibenzofurandiols on treatment with sodium methoxide in boiling methanol.A convenient synthesis of dimethyl furan-2,5-diylacetate (30) is described, as are attempts to synthesize 1,3,7,9-tetramethoxy-2,8-dimethyldibenzofuran (3).
A C-Methylbiflavone from Cephalotaxus harringtonia K. Koch
Agil, Mohammad,Rahman, Wasiur,Hasaka, Noriko,Okigawa, Masayoshi,Kawano, Nobusuke
, p. 1389 - 1392 (2007/10/02)
6-C-Methyl-7-O-methylamentoflavone (1) isolated from the leaves of Cephalotaxus harringtonia K.Koch (Cephalotaxaceae) has been identified on the basis of the spectral data of its hexamethyl ether (1a) and its penta-acetate (1b).The location of the C-methyl group was first deduced from 1H n.m.r. studies with a lanthanide shift reagent and confirmed by a synthesis of the hexamethyl ether (1a).
