78 results about "Oxidative cyclization" patented technology

The invention discloses a method for preparing a quinolizinones compound in a formula I, which comprises: S (A), oxidizing a compound in a formula III in a solvent under the action of an oxidizing agent and under the electro-oxidation and reduction condition or under the photo-oxidation and reduction condition, and then processing the compound by acid to obtain a ringed syn-oxime compound in a formula II; and S (B), carrying out hydrolysis on the compound in the formula II to obtain the compound in the formula I. The invention further discloses another method for preparing the quinolizinones compound in the formula I on the basis of the same conception. The two methods have key points that before oxidative cyclization, a pyrazine ring is closed in a raw material compound, and due to the influence of a steric hindrance, when oxidative cyclization is carried out to form a five-membered ring, ring closing can only be carried out selectively at the same side of the pyrazine ring so as to obtain a syn-oxime structure, i.e., a syn-oxime isomer can be highly selectively generated.

The invention relates to a method for preparing an israbipine medicament for treating hypertension. Particularly the method of the invention comprises the following steps: (a) carrying out oxidative cyclization on 2-amino-3-methyl nitrobenzene to form 4-methyl benzofuroxan oxide; (b) reducing the 4-methyl benzofuroxan oxide to form 4-methyl benzofuroxan; (c) carrying out substitution bromination on the 4-methyl benzofuroxan to form 4-bromomethyl benzofuroxan; (d) carrying out hydrolyzation on the 4-bromomethyl benzofuroxan to form 4-hydroxymethyl benzofuroxan; (e) carrying out oxidation on the 4-hydroxymethyl benzofuroxan to form 4-formaldehyde benzofuroxan; and (f) performing a reaction of the 4-formaldehyde benzofuroxan amd alpha-aminocrotonic acid isopropyl ester to form israbipine. The method of the invention has high yield and simple and convenient operation and can prepare high-purity israbipine.

The present invention disclosed herein is a novel commercially feasible, one pot synthesis of library of 3-substituted phthalides of formula I via CuCN mediated oxidative cyclization in high yield. Formula I

The present invention relates to pseudoginseenoside-Pdq and its semi-synthesis process and medicinal use, and belongs to the field of new compound and its synthesis and medicinal use. The material 20(S)-protopanoxadiol saponin or 20(R)-protopanoxadiol saponin is processed through oxidation, cyclization and other steps under acid condition to produce pseudoginseenoside-Pdq as one new compound, named chemically as damar-20S, 20R-epoxy-3beta, 12beta, 25-triol. Pseudoginseenoside-Pdq has wide application in preparing medicine for treating coronary heart disease, myocardial ischemia, ischemic shock, arrhythmia, etc.

The invention relates to a method for synthesizing a benzofluorenone compound through photocatalysis. The method comprises the following steps: mixing a compound represented by a formula (I), a compound represented by a formula (II), a photosensitizer and a solvent, reacting for 1-3 h at a temperature of 30-50 DEG C under the irradiation of 15 W blue LED light, and performing post-treatment on thereaction liquid to obtain a benzofluorenone compound represented by a formula III. According to the invention, the method is safe, environment-friendly, free of waste gas and low in operation risk; the substrate adaptability is good, and oxidative cyclization of various substituent groups can be realized; reaction conditions are mild; and the benzofluorenone is synthesized by adopting a photocatalysis mode in the reaction, so that the method is more environment-friendly and is closer to the concept of green chemistry.

The invention relates to a solid-phase synthesis method for edotreotide. The technical problem that an industrial synthesis method for the compound does not exist at present is mainly solved. The method disclosed by the invention mainly comprises the following steps: 1, coupling Fmoc-Thr(tbu)-Ol and dichlorotriphenyl chloride resin to obtain Fmoc-Thr(tbu)-Ol-2Cl-Trt Cl resin; 2, connecting remaining amino acids in sequence by virtue of a solid-phase synthesis method so as to obtain an edotreotide resin peptide I; 3, performing oxidative cyclization on the resin by using iodine so as to obtainan edotreotide resin peptide II; 4, performing Fmoc-removing protection, and coupling DOTA(Otbu)-3-COOH so as to obtain an edotreotide resin peptide III; 5, cracking to obtain crude edotreotide, purifying and refining through reversion phase chromatography, and freezing, so as to obtain the refined edotreotide. The invention provides a chemical synthesis method of edotreotide.

The present invention discloses a tetra-substituted imidazole synthesis method, wherein amidine and chalcone derivatives are adopted as raw materials and chlorobenzene is adopted as a solvent. Meanwhile, ferric trichloride and iodine are adopted as catalysts. In this way, the tetra-substituted imidazole is synthesized through the oxidative cyclization reaction. The above raw materials of the method are readily available, and the operation of the method is simple. Meanwhile, the method is mild in reaction condition, high in yield and strong in practicality, thus being suitable for industrial production.

The invention relates to a new use of 20(S)-protopanoxadiol derivatives and 20(S)-protopanaxatriol derivatives, and mainly relates to a use in the preparation of medicines for treating or preventing depressive mental diseases. 20(S)-protopanoxadiol and 20(S)-protopanaxatriol are used as raw materials, and undergo oxidative cyclization to prepare dammara-20S-24(R)-epoxy-3beta,12beta,25-triol, dammara-20S-24(S)-epoxy-3beta,12beta,25-triol, dammara-20S-24(S)-epoxy-3beta,6beta,12beta,25-tetrol or dammara-20S-24(R)-epoxy-3beta,6beta,12beta,25-tetrol. Researches of pharmacological experiments show that dammara-20S-24(R/S)-epoxy-3beta,12beta,25-triol and dammara-20S-24(R/S)-epoxy-3beta,6beta,12beta,25-tetrol can obviously shorten the tail immobility time of mice in mouse tail suspension tests of a classic depression model, and can obviously shorten the swimming immobility time of the mice in mouse forced swimming model tests, so dammara-20S-24(R/S)-epoxy-3beta,12beta,25-triol and dammara-20S-24(R/S)-epoxy-3beta,6beta,12beta,25-tetraol have potential development values in the preparation of medicines for treating or preventing depressive mental diseases.

The invention provides a method for preparing 1, 2-benzisothiazoline-3-one through catalytic oxidation, which comprises the following steps of: by taking a metal manganese salt or a manganese complex as a catalyst, carrying out oxidative cyclization reaction on an amine compound in an oxygen or air environment to generate the 1, 2-benzisothiazoline-3-one. In the reaction, oxygen or air is used as an oxidant; the catalyst is simple, cheap, high in catalytic activity and high in reaction efficiency; the preparation process is simple, the product selectivity is high, and byproducts are few; and less waste is produced, and the method is environment-friendly, and has a relatively good industrial application prospect.

The invention relates to a thiophene macrocyclic compound and a preparation method of derivatives of the thiophene macrocyclic compound, in particular to a preparation method of a thiophene eight membered cyclic compound and a thiophene twelve membered cyclic compound. The preparation method is as follows: 2, 2`-dibromo-[3, 3`]-bithiophene is adopted as the raw material; lithium diisopropylamide (LDA) is firstly used to capture the Alpha- proton, then the 2, 2`-dibromo-[3, 3`]-bithiophene is quenched by trimethylchlorosilane, and a compound 3 is prepared; then the compound 3 and butyl lithium generate bromine and lithium exchanging reaction, and copper chloride oxidative cyclization is used to generate thiophene eight membered cyclic compound 4 and thiophene twelve membered cyclic compound 5, wherein, the yield of the compound 5 reaches up to 36 percent; and in the condition that trifluoroacetic exists, the compound 4 and the compound 5 remove TMS, and a compound 1-four (2,3-bithiophene) and a compound 2-six (2,3-bithiophene) are obtained. The preparation method of the derivatives of the thiophene macrocyclic compound realizes the aim of preparing the thiophene eight-membered cyclic compound at high yield, and most importantly, the preparation method realizes the aim of preparing the thiophene twelve-membered cyclic compound at high yield, and the total yield of the three steps reaches up to 27 percent. The synthetic process of the method has operability, and the reaction conditions of waterless, oxygen free and low-temperatured. Thus, the preparation method is suitable for scale preparation.

The invention discloses a preparation method of a polysubstituted 2-aryl indole derivative. The method specifically comprises the following steps: by taking a 2-acetenyl aniline compound and a ketonecompound as raw materials, carrying out oxidative cyclization reaction on the 2-acetenyl aniline compound and the ketone compound under the action of a catalyst, a ligand and an oxidizing agent to prepare the polysubstituted 2-arylindole derivative. The method provided by the invention has the characteristics of easily available raw materials, simple operation, high chemical selectivity and regioselectivity, and the like, and has great implementation value and social and economic benefits.

The invention discloses a new synthesis technology of benthiavalicarb isopropyl, and belongs to the field of pesticide chemistry. A method for implementing the synthesis technology comprises the steps as follows: fluorocyclohexanone is used as a raw material and catalyzed by iodine to generate 2-amino-6-fluorobenzothiazole through oxidative cyclization, and after hydrolysis and acidification, 2-amino-5-fluorothiophenol is prepared; meanwhile, D-alanine is used as a raw material and reacts with triphosgene to generate (R)-4-methyl-oxazolidine-2, 5-diketone, and an intermediate reacts with 2-amino-5-fluorothiophenol to prepare chiral (R)-1-(6-fluorine-benzothiazole-2-) ethylamine; and L-valine is used as a raw material and reacts with isopropyl chlorocarbonate to prepare N- Isopropoxy carbonyl-L-valine, carboxyl activation is performed simultaneously, and finally, the raw materials and (R)-1-(6-fluorine-benzothiazole-2-) ethylamine perform a one-pot reaction to directly generate benthiavalicarb isopropyl. The synthesis technology has short process route and high total yield, and purity degree is higher than 95%.

The invention relates to a fluorescence detection reagent for tetravalent cerium ions and a fluorescence detection method thereof, tetravalent cerium ions are used as a single-electron oxidizing agentto promote o-phenylenediamine to be oxidized, cyclized and condensed to form a yellow fluorescence product 2, 3-diaminophenazine, so that a Ce (IV) ion fluorescence detection method is established. The fluorescence detection method of the tetravalent cerium ions has good selectivity and linear relation and strong fluorescence response, and can quantitatively detect the concentration of the tetravalent cerium ions.

The invention relates to the technical field of catalytic synthesis, and concretely relates to application of a porphyrin-based covalent organic framework material in photocatalytic oxidation cyclization reaction. The structure of the porphyrin-based covalent organic framework material is as shown in formula I. A synthesis method of an N-methyltetrahydro-1H-pyrrolo[3, 4-c]-quinoline-1, 3(2H)-dione derivative comprises the following steps: adding an N, N-dimethylaniline derivative and a maleimide derivative into an organic solvent to obtain a solution A; adding the material in the formula I into the solution A to obtain a solution B; and irradiating the solution B with visible light to obtain a product. A metal-free covalent organic framework based on a porphyrin structure is used as a photosensitizer, oxygen is used as an oxidizing agent, an oxidative cyclization reaction of the N, N-dimethylaniline derivative and the maleimide derivative is realized under the irradiation of visible light, and the tetrahydroquinoline compound is efficiently constructed; and the method is green and mild in condition, the photosensitizer can be recycled, the utilization rate of the photosensitizer is increased, the cost is reduced, and industrial popularization and application are facilitated.

The invention provides a method for preparing Setmelanotide. According to the method, amino resins are used as starting resins, corresponding protecting amino acids are sequentially inoculated according to the reverse direction of the amino sequence of the Setmelanotide, so that Setmelanotide peptide resins are obtained; the Setmelanotide protecting peptide resins are subjected to acidolysis and oxidative cyclization to obtain Setmelanotide crude products; and the Setmelanotide crude products are subjected to purification and freeze drying to obtain Setmelanotide pure products. The technologyis simple to operate, and the products are high in total yield, and suitable for large-scale production.

The invention provides a method for synthesizing a naphthol [2, 1-d] oxazole compound through oxidative cyclization of a naphthol compound and an amine compound under a metal-free condition. Many functional groups, such as Me, OMe, tBu, F, Cl, Br, I, CF3, CN, NO2, CHO, ester and anhydride groups, furfuryl, thienyl and pyridyl, are easily transferred into the desired product, which is not achieved by other methods. Based on the advantage, the method can provide a variety of new naphtho [2, 1-d] oxazole compounds. The method has the advantages of being high in universality, high in efficiency, good in selectivity, good in atom and step economy, easy in substrate obtaining, mild in condition, easy and convenient to operate and the like, and therefore the reaction can be widely applied to the fields of chemistry, biology, medicine and material science.

The invention discloses a method for constructing 3,5-disubstituted pyridine by utilizing mixed styrene derivative and N,N-dimethylformamide. The method comprises the following step: subjecting the mixed styrene derivative, N,N-dimethylformamide and peroxydisulfate to a cyclization reaction under the catalytic action of iodized salt so as to obtain symmetrical and asymmetrical mixed 3,5-disubstituted pyridine products at the same time. According to the method, 3,5-disubstituted pyridine is synthesized from the mixed styrene derivative and DMF through one-step oxidative cyclization under the catalysis of iodate; and the method has the advantages of low raw material and catalyst cost, mild reaction conditions, capability of realizing high-yield preparation of the symmetrical and asymmetrical3,5-disubstituted pyridine products at the same time and the like.

The invention relates to the field of synthesis of tryptanthrin and discloses a preparation method of a tryptanthrin compound. The tryptanthrin compound is a compound having a structure shown in formula (2); the preparation method comprises a step of performing oxidative cyclization reaction on a compound having a structure shown in formula (1) in an organic solvent in the presence of a peroxide and an alkaline compound to obtain the compound having the structure shown in formula (2); the peroxide is selected from tert-butyl hydroperoxide and/or hydrogen peroxide. Raw materials used in the preparation method provided by the invention are simple, low in toxicity, green and environment-friendly; the preparation method realizes reaction at room temperature basically, are mild in condition, and can be used for implementing industrial production of the tryptanthrin compound.

The invention provides a method for synthesizing an indole compound by iodine-induced electrocatalytic intramolecular C(sp2)-H oxidative cyclization. The preparation method comprises the following steps: mixing iodized salt electrolyte, a 2-vinyl aniline compound and thiocyanate, and performing an intramolecular oxidative cyclization reaction under electrochemical conditions to obtain the indole compound. The invention provides a method for non-metallic catalytic electrochemical synthesis of indole compounds, so that a plurality of important drug intermediates can be derived. According to the method, no metal or chemical oxidizing agent is used, no iodobenzene or other by-products are generated, the reaction is green and environmentally friendly, the atom economy is high, and the gram-scale experiment yield is kept.

The invention provides an application of a silver catalyst in preparation of an antibacterial drug intermediate fosfomycin levoforight amine salt. The application is characterized by comprising the following steps: at room temperature, dissolving cis-propenylphosphonic acid in an alcohol solvent, slowly dropwise adding (+) alpha phenylethylamine, regulating the pH value of the system to 5.5-6 after dropwise adding, continuing stirring for 1-3 minutes, and adding the silver catalyst, continuously and slowly dropwise adding hydrogen peroxide, then continuously stirring for 10-30 minutes, quicklyheating the system to 50-55 DEG C, filtering while the system is hot, and cooling, crystallizing and washing the filtrate to obtain the fosfomycin levoforight amine salt. Silver carbonate is used asthe catalyst, hydrogen peroxide is used as an oxidizing agent, heating is not needed in the oxidative cyclization process, and the reaction can be performed at normal temperature. Silver carbonate hasvery high catalytic activity in the invention, and compared with the prior art, the application has the advantages of small dosage, mild reaction, effective shortening of the reaction time, simple post-treatment, and realization of separation of the catalyst from the system only through filtration of the system while the system is hot.