- Preparation method of 2, 5-dimethoxyphenylacetic acid
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The invention belongs to the technical field of drug synthesis, and particularly relates to a preparation method of 2, 5-dimethoxyphenylacetic acid, which comprises the following steps: A. Reacting 1,4-dimethoxybenzene with formaldehyde under the action of hydrogen halide, extracting by the reaction system, merging with organic phases, drying, concentrating under reduced pressure, and purifying the crude product to obtain 2-halon methyl-1, 4-dimethoxybenzene ; and B, under the protection of inert gas, putting the 2-halo methyl-1, 4-dimethoxybenzene obtained in the step A, magnesium or butyl lithium and carbon dioxide into a solvent, and then carrying out extraction and deactivation, reduced pressure distillation, extraction, organic phase combination and reduced pressure concentration toobtain the 2, 5-dimethoxyphenylacetic acid. The yield and the total yield of the 2, 5-dimethoxyphenylacetic acid obtained by the method disclosed by the invention are both higher than those of the 2,5-dimethoxyphenylacetic acid synthesized by a Willgerodt-Kindler method.
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Paragraph 0020-0023; 0027-0030; 0034-0037
(2021/01/29)
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- Preparation method of 2,5-dimethoxyphenylacetic acid
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The invention belongs to the technical field of drug synthesis, and particularly relates to a preparation method of 2,5-dimethoxyphenylacetic acid, wherein the preparation method comprises the following steps: A, reacting 1,4-dimethoxybenzene with formaldehyde under the action of hydrogen halide to obtain 2-halomethyl-1,4-dimethoxybenzene; B, reacting 2-halomethyl-1,4-dimethoxybenzene obtained inthe step A with a cyanation reagent, then diluting, washing, drying and concentrating under reduced pressure, and finally carrying out reduced pressure distillation to obtain 2(2,5-dimethoxyphenyl)acetonitrile; and C, hydrolyzing the 2(2,5-dimethoxyphenyl)acetonitrile obtained in the step B, cooling, extracting, merging, drying, concentrating under reduced pressure and purifying to finally obtainthe 2,5-dimethoxyphenylacetic acid. The yield and the total yield of the 2,5-dimethoxyphenylacetic acid obtained by the method disclosed by the invention are both higher than those of the 2,5-dimethoxyphenylacetic acid synthesized by a Willgerodt-Kindler method, and the yield and the total yield of the 2,5-dimethoxyphenylacetic acid are higher than those of 2,5-dimethoxyphenylacetic acid synthesized by the Willgerodt-Kindler method.
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Paragraph 0021-0024; 0029-0032; 0037-0040
(2021/02/06)
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- Promotion of Appel-type reactions by N-heterocyclic carbenes
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N-Heterocyclic carbenes (NHCs) have been extensively used as a versatile class of catalysts and ligands in organocatalytic and organometallic chemistry. However, there are only a small number of synthetic applications where they act as reagents. Here we demonstrate that NHCs can be used as stoichiometric redox reagents for Appel-type halogenation reactions of alcohols. This new reactivity reveals a fresh and interesting aspect and enriches the chemistry of NHCs in an underexplored area. The potential of performing this chemical transformation at the catalytic level using an NHC-oxide derivative is also investigated.
- Hussein, Mohanad A.,Nguyen, Thanh Vinh
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supporting information
p. 7962 - 7965
(2019/07/12)
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- Beyond PCBM: Methoxylated 1,4-bisbenzyl[60]fullerene adducts for efficient organic solar cells
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Organic solar cells have been based mostly on conjugated polymers and the classic fullerene derivative PCBM and are characterized by modest open circuit voltages (Voc). Increasing Voc requires fullerene acceptors with higher LUMOs th
- Huang, Shaohua,Zhang, Guangye,Knutson, Nicholas S.,Fontana, Matthew T.,Huber, Rachel C.,Ferreira, Amy S.,Tolbert, Sarah H.,Schwartz, Benjamin J.,Rubin, Yves
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supporting information
p. 416 - 424
(2016/01/15)
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- N-(5-fluoro-2-phenoxyphenyl)-N-(2-[131I]iodo-5-methoxybenzyl) acetamide: A potent iodinated radioligand for the peripheral-type benzodiazepine receptor in brain
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To image the peripheral-type benzodiazepine receptor (PBR) in vivo, we previously developed two positron emission tomography (PET) ligands, N-(2-[ 11C],5-dimethoxybenzyl)-N-(5-fluoro-2-phenoxyphenyl)acetamide ([ 11C]1a) and its [sup
- Zhang, Ming-Rong,Kumata, Katsushi,Maeda, Jun,Haradahira, Terushi,Noguchi, Junko,Suhara, Tetsuya,Halldin, Christer,Suzuki, Kazutoshi
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p. 848 - 855
(2007/10/03)
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- Synthesis and antiparasitic and antitumor activity of 2,4-diamino-6- (arylmethyl)-5,6,7,8-tetrahydroquinazoline analogues of piritrexim
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Nineteen previously undescribed 2,4-diamino-6-(arylmethyl)-5,6,7,8- tetrahydroquinazolines (5a-m, 10-12) were synthesized as part of a larger effort to assess the therapeutic potential of lipophilic dihydrofolate reductase (DHFR) inhibitors against opportunistic infections of AIDS. Condensation of appropriately substituted (arylmethyl)triphenylphosphoranes with 4,4-ethylenedioxycyclohexanone, followed by hydrogenation (H2/Pd-C) and acidolysis, yielded the corresponding 4-(arylmethyl)cyclohexanones, which were then condensed with cyanoguanidine to form the tetrahydroquinazolines. Three simple 2,4-diamino-6-alkyl-5,6,7,8-tetrahydroquinazoline model compounds (9a-c) were also prepared in one step from commercially available 4-alkylcyclohexanones by this method. Enzyme inhibition assays against rat liver DHFR, Pneumocystis carinii DHFR, and the bifunctional DHFR-TS enzyme from Toxoplasma gondii were carried out, and the selectivity ratios IC50(rat)/IC50(P. carinii) and IC50(rat)/IC50(T. gondii) were compared. The three most potent inhibitors of P. carinii DHFR were the 2,5- dimethoxybenzyl (5j), 3,4-dimethoxybenzyl (5k), and 3,4,5-trimethoxybenzyl (51) analogues, with IC50 values of 0.057, 0.10, and 0.091 μM, respectively. The remaining compounds generally had IC50 values in the 0.1- 1.0 μM range. However all the compounds were more potent against the rat liver enzyme than the P. carinii enzyme and thus were nonselective. The T. gondii enzyme was always more sensitive than the P. carinii enzyme, with most of the analogues giving IC50 values of 0.01-0.1 μM. Moderate 5-10-fold selectivity for T. gondii versus rat liver DHFR was observed with five compounds, the best combination of potency and selectivity being achieved with the 2-methoxybenzyl analogue 5d, which had an IC50 of 0.014 μM and a selectivity ratio of 8.6. One compound (51) was tested for antiproliferative activity against P. carinii trophozoites in culture at a concentration of 10 μg/mL and was found to completely suppress growth over 7 days. The suppressive effect of 51 was the same as that of trimethoprim (10 μg/mL) + sulfamethoxazole (250 μg/mL), a standard clinical combination for the treatment of P. carinii pneumonia in AIDS patients. Four compounds (5a,h,k,l) were tested against T. gondii tachyzoites in culture and were found to have a potency (IC50 = 0.1-0.5 μM) similar to that of pyrimethamine (IC50 = 0.69 μM), a standard clinical agent for the treatment of cerebral toxoplasmosis in AIDS patients. Compound 5h was also active against T. gondii infection in mice when given qdx8 by peritoneal injection at doses ranging from 62.5 (initial dose) to 25 mg/kg. Survival was prolonged to the same degree as with 25 mg/kg clindamycin, another widely used drug against toxoplasmosis. Three compounds (5j-l) were tested for antiproliferative activity against human tumor cells in culture. Among the 25 cell lines in the National Cancer Institute panel for which data were confirmed in two independent experiments, the IC50 for at least two of these compounds was 50 of 50 was 0.01 μM.
- Rosowsky, Andre,Papoulis, Andrew T.,Forsch, Ronald A.,Queener, Sherry F.
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p. 1007 - 1017
(2007/10/03)
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- Pulse radiolytic kinetic study of the decay of α-methyl-substituted benzoquinone radical anions: A possible mechanistic model for bioreductive alkylation
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Pulse radiolysis and transient absorption spectroscopy were used to kinetically characterize the decay of several α-methyl-substituted 1,4-benzoquinone radical anions. Electron attachment rates, absorption spectra, extinction coefficients, and pKa/s
- O'Shea, Kevin E.,Fox, Marye Anne
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p. 611 - 615
(2007/10/02)
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- Therapeutic agent for liver disease and piperazine derivatives
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A therapeutic agent for liver disease containing as an active ingredient a piperazine derivative having the formula: STR1 wherein, A represents a phenyl, p-benzoquinonyl or cumarinyl group which may have at least one substituent selected from the group consisting of halogen, alkyl, fluoroalkyl, formyl, alkoxycarbonyl, acyl, hydroxy, alkoxy, acyloxy, glycosyloxy, amino, alkylamino, mercapto, alkylthio and nitro; B represents a single bond or a straight chain alkylene group containing 1-4 carbon atoms which may have at least one substituent selected from the group consisting of alkyl, aryl, aralkyl, hydroxy and oxo; R represents an atom or a group selected from the group consisting of hydrogen, alkali metal, alkaline earth metal, alkyl, cycloalkyl, aralkyl and aryl; and n is 2 or 3, or its pharmaceutically acceptable salt is disclosed.
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- Process for preparing fluorinated amino-nitriles
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Certain α-(fluoromethyl or difluoromethyl)-α-aminoacetonitriles are prepared by treating the appropriate α-(fluoromethyl or difluoromethyl) ketimine magnesium halide with hydrogen cyanide or with an alkali metal cyanide or ammonium cyanide and a proton source. The products are useful as intermediates for making α-(fluoromethyl or difluoromethyl)-α-amino acids having pharmacological activity.
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- Method of depleting endogenous monoamines
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2-Amino-2-fluoromethyl-3-(substituted)phenyl propionic acids and derivatives thereof are coadministered with dopamine for the treatment of schizophrenia, mania, tardive dyskinesia, anxiety, or depression.
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