61 results about "Meldrum's acid" patented technology

The invention relates to (E)-3-(2,4,5-trimethoxy-phenyl)-prop-2-en-1-ol, and a preparation method and application thereof. Related (E)-3-(2,4,5-trimethoxy-phenyl)-prop-2-en-1-ol has the structural formula I shown in the specification. The related preparation method comprises: performing decarboxylation reaction on 2,4,5-trimethoxybenzaldehyde, isopropylidene malonate (meldrum's acid) and a fatty alcohol under catalytic effect of pyridine and piperidine, so as to obtain (E)-2,4,5-trimethoxycinnamate, and processing by using a reducing agent, so as to obtain (E)-3-(2,4,5-trimethoxy-phenyl)-prop-2-en-1-ol. The preparation method is simple and relatively high in yield. The related application comprises that (E)-3-(2,4,5-trimethoxy-phenyl)-prop-2-en-1-ol is applied to prepare medicines for calming, tranquilizing, resisting senile dementia, resisting convulsion, resisting epilepsy or protecting heart and cerebral vessels.

The invention belongs to the field of compound preparation, and specifically discloses a preparation method of an anti-tumor medicine chlorambucil. The preparation method comprises the steps of performing a Vilsmeier reaction on a raw material N,N-dihydroxyethylaniline and phosphorus oxychloride and DMF so as to prepare 4-[bi(2-chloroethyl)amino]benzaldehyde, then performing a witting reaction on4-[bi(2-chloroethyl)amino]benzaldehyde and methoxymethyl triphenylphosphonium chloride so as to prepare 4-[bi(2-chloroethyl)amino]-BETA-methoxystyrene, reacting under an acid condition so as to obtain4-[bi(2-chloroethyl)amino]phenylacetaldehyde, and finally, reacting with Meldrum's acid in triethylamine and formic acid systems so as to prepare a target product. The raw material N,N-dihydroxyethylaniline is cheap, has a wide source and is easy to obtain; the whole reaction process has high yield, production conditions are mild, the steps are short, and post treatment and purification are easyto operate, so that the preparation method is applicable to commercial large scale production, and meets the rapidly growing market demands.

A specific technique of a method of synthesizing 4-hydroxycoumarin and derivatives of 4-hydroxycoumarin is as follows: taking a phenol or the derivatives of the phenol and an Meldrum's acid as the raw materials, using a thin layer method to monitor and then decompressing to remove an acetone after complete reaction; with no necessity of separating an intermediate product, directly carrying out intermolecular dehydration with an ito agent or a polyphosphoric and ring-closing reaction and finally adding water to precipitate a sedimentation, filtrating and then recrystallizing to get a final product---4-hydroxycoumarin and the derivatives of 4-hydroxycoumarin. The proportion of the phenol, the derivatives of the phenol, the Meldrum's acid, the ito agent or the polyphosphoric is 1.0mmol:1.0mmol:1-3ml or 1 to 2g. The temperature of intermolecular ring-closing reaction when adding the ito agent is 60 DEG C to 70 DEG C; the reaction time is 1 to 5 hours. The temperature of intermolecular ring-closing reaction when adding the polyphosphoric is 110 DEG C to 120DEG C; the reaction time is 3 to 7 hours. The method has the advantages of easy raw material obtaining, mild reaction condition, simple operation condition and less pollution. Furthermore, the yield varies from medium to excellence; no catalyst is needed; the method also assures a high yield ratio.

The invention relates to a preparation method of 5-(arylmethylene) meldrum's acid, which comprises the following steps of: a, dissolving aromatic aldehyde and aniline according to the mol rate of 1.0:(1.0-1.2) into water, wherein the aromatic aldehyde has a structural formula described in the specification, R is H, X (halogen), alkyl (such as CH3, C2H5), alkoxy (such as OCH3, OCH2CH3), OH, NO2 and CN; and b, respectively dissolving arylmethylene aniline obtained from the step a and meldrum's acid into an alcohol solution according to the mol ratio of (1.1-1.2):1.0 to obtain respective saturated solutions, then adding the alcohol saturated solution of the arylmethylene aniline into the alcohol saturated solution of the meldrum's acid, stirring for reacting for 3-4min, filtering after the reaction is ended, washing filter residue with water, drying and then recrystallizing to obtain the 5-(arylmethylene) meldrum's acid. The preparation method has the advantages of environment protection because of using water and alcohol as solvents, mild reaction condition, convenient posttreatment and higher yield of products.

The invention relates to a method for preparing 4-acetyl-1-naphthoic acid, and belongs to the technical field of pharmacy. According to the method provided by the invention, 1, 4-naphthalic acid which is low in price and easy to obtain is taken as a raw material, and 4-acetyl-1-naphthoic acid is prepared by adding Meldrum's acid, performing decarboxylation to formylate carboxyl, and finally performing hydrolysis. According to the method provided by the invention, a high-purity product can be obtained, an inflammable metal reagent methyl zinc is not used in the process, the reaction condition is mild, the operation is simple, and the method is suitable for industrial large-scale production.

The invention belongs to a pesticide and discloses tetrahydropyridone 1,3-diazacyclo cis-neonicotine compounds shown in a general formula (I) as well as a preparation method and applications thereof. The preparation method comprises the following steps: using ethanol as solvent, and adding neonicotine compounds, aldehyde and Meldrum's acid; and adding piperidine used as a catalyst, and refluxing to react. In the method, a tetrahydropyridone structure is introduced in the neonicotine compounds for the first time. The tetrahydropyridone 1,3-diazacyclo cis-neonicotine compounds have the following advantages: the preparation process is simple, and the yield is high; the preparation process has no pollution; and the compounds have good insecticidal effects and are safe for human and livestock.

The invention discloses a method for preparing (3R, 5S)-3, 5-O-isopropylidene-3, 5, 6-trihydroxy caproic acid hexylic acid derivative, including the following steps: (1) L-malic acid protected hydroxy compound and carbonyl diimidazole (CD I) react in solvent to obtain (S)-2,2- dimethyl-5-oxo-1, 3-dioxa-4-acetyl imidazole; (2) the (S)-2,2- dimethyl-5-oxo-1, 3-dioxa-4-acetyl imidazole and Meldrum's acid react in the solvent under the existence of basic catalyst to prepare (S)-2-(4'-oxo-3', 4'-O-isopropylidene-3', 4'-dihydroxy-1'-hydroxy-alkene)-malonic acid cyclic isopropylidene ester; (3) the (S)-2-(4'-oxo-3',4'-O-isopropylidene-3',4'-dihydroxy-1'-hydroxy-alkene)-malonic acid cyclic isopropylidene ester reacts with methanol to prepare (S)-3, 6-dioxo-5, 6-isopropylidene-5, 6-dihydroxy tert-butyl ester hexanoate; and a target compound can be obtained after further reaction. The method has the advantages of easy acquisition of materials, moderate reaction condition, less material consumption, high product quality and yield and easy implementation of industrialization.

The invention discloses an industrial preparation method of acetyl tetrahydrofuran with a high optical purity, and belongs to the field of chemical synthesis. According to the preparation method, tetrahydrofuroic acid is taken as the raw material and then is chlorinated to obtain tetrahydrofuran carbonyl chloride, tetrahydrofuran carbonyl chloride and Meldrum's acid carry out condensation reactions, and reaction product is hydrolyzed to obtain the target compound namely acetyl tetrahydrofuran. The preparation method has the advantages that the raw material cost is low, the preparation method does not need any Grignard reagent, the product property is stable, the purity can reach 98% or more, the optical purity can reach 99% or more, and the yield can reach 70% or more. The method has applied to industrial production. The product quality is stable. The reaction conditions are mild. The operation is safe and reliable. Dichloromethane can be recycled. The technology has the advantages of good repeatability and low preparation cost, and is a reliable industrial production method of acetyl tetrahydrofuran with a high optical purity.

The present invention belongs to the technical field of medicine, and relates to a preparation method of (S)-4-amino-5-mercaptopentanoic acid having potential medical application value. According to the method of the present invention, amino-protected and mercapto-protected D-cysteine is adopted as a raw material and is subjected to condensation with Meldrum's acid to generate beta-ketone ester, the ketone carbonyl is subjected to reducing elimination, lactam is formed through decarboxylation, the protection groups on mercapto and amino are removed, and the lactam ring is opened to prepare the (S)-4-amino-5-mercaptopentanoic acid. According to the present invention, the method has following advantages that reaction steps are short, wherein only the four steps are required; the purification is easy, wherein only the simple washing operation is required; and the yield is high, wherein the total yield of the four steps is 76.0%.

The invention provides a synthetic method of oat alkaloid and studies a chemical synthesis process of oat alkaloids A, B and C. The oat alkaloids A, B and C are synthesized by taking 2-amino-5-hydroxybenzoic acid, meldrum's acid, 4-hydroxybenzaldehyde, 4-hydroxyl-3-methoxybenzaldehyde and 3,4-dihydroxy benzaldehyde as raw materials and using a Knoevenagel condensation reaction. Analysis means suchas infrared spectroscopy, nuclear magnetic resonance spectroscopy, mass spectroscopy and elemental analysis are applied to perform structural characterization on a compound, so that the feasibility of a process route of synergizing the oat alkaloids is demonstrated, and the synthetic process conditions are optimized; the synthetic method has important research significance for further developmentof application of oat alkaloids with multiple bioactive functions such as oxidation resistance. The development of the chemical synthesis technology has a very broad application prospect.

The invention discloses a preparation method for a coumarin-3-carboxylic ester derivative shown as the formula (I) or the formula (II) in the specification. The method comprises the step that under the existence of FeCl3 being used as a catalyst, salicylaldehyde derivative shown as the formula (III) in the specification and 2-hydroxy-1-naphthaldehyde shown as the formula (IV) in the specification are in contact reaction with alcohol and meldrum's acid which have a general formula, namely R2OH. Through the fact that the salicylaldehyde derivative, the 2-hydroxy-1-naphthaldehyde, the alcohol or the meldrum's acid is catalyzed by FeCl3 in multi-component contact reaction under a relatively temperate condition, the coumarin-3-carboxylic ester derivative with relatively high productivity is synthesized in relatively short reaction time, and the method is simple in step, efficient and environment-friendly, and completely meets the concept of green chemistry.

The invention relates to a synthesis method of a sitagliptin phosphate intermediate, and belongs to the technical field of organic synthesis. The method comprises the following technological steps of synthesizing a reaction liquid of 5-hydroxyl-[(2,4,5-trifluoro-phenyl)-ethylidene]-dimethyl-[1,3] dioxo-4,6-diketone from 2,4,5-trifluoro-phenylacetic acid, meldrum's acid, N,N-diisopropylethylamine, DMAP and acetylchloride; adding 3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4] triazol [4,3-alpha] pyrazine hydrochloride and trifluoroacetic acid to obtain the product. According to the method, the reaction raw materials are easily available; the reaction process is simple in operation; the requirements on reaction equipment are low; the reaction conditions are relatively mild; the yield and content are high, the quantity of waste water and solid wastes is relatively low, the cost is saved, and the method is suitable for industrial production.

The invention discloses a photoresist resin monomer containing a Meldrum's acid structure, and relates to the field of photoresist resin monomers. The structural formula of the photoresist resin monomer is shown in the specification, R1 is methyl or H, R2 is alkyl, naphthenic base, alkyl containing O atoms, or naphthenic base containing O atoms, R3 is H or alkyl, and the resin monomer is beneficial to increase of the alkali solubility of the photoresist resin, the edge side roughness of a photo-etched pattern can be improved, the etching resistance is better, the resolution of the photo-etched pattern is greatly improved, and the adsorption force of the photoresist on a silicon wafer can be improved.

The invention discloses a synthesis method of (R)-4-propyldihydrofuran-2-ketone, and belongs to the field of organic chemical synthesis. A new process route is developed to overcome the defects that (R)-4-propyldihydrofuran-2-ketone is relatively high in material price, low in product purity, difficult to produce and amplify and the like. Meldrum's acid and R-epichlorohydrin are used as initial raw materials, and the compound is obtained by taking (1S, 5R)-3-oxabicyclo [3.1. 0]-2-hexanone as an intermediate through a two-step reaction of closing a three-membered ring and opening a ring by using a Grignard reagent. The (R)-4-propyldihydrofuran-2-ketone is synthesized by adopting the synthesis method, a novel process route is adopted in the process, the total molar yield is greater than 50%,and the method has the characteristics of novel and short route, high optical purity, low cost and the like.

The invention discloses a method for measuring the content of Meldrum's acid and is characterized in that peak areas of Meldrum's acid in a solution of a Meldrum's acid standard product and a solutionof a Meldrum's acid sample for test are separately measured by high performance liquid chromatography; and according to the obtained peak areas, calculating the mass content of Meldrum's acid in thesolution of the Meldrum's acid sample for test by using an external standard method. The method, which specifically limits chromatographic conditions for applying high performance liquid chromatography to measure the content of Meldrum's acid, is a simple content detection method with good separation effect, high accuracy and high precision. The method has a wide detection range and is accurate indetection results.

Compounds, methods of synthesis, and methods of cancer treatment by arylidene-1,3-dioxane-4,6-diones. A Meldrum's acid-based chemistry and hybrid solid-liquid method. The method includes protection of ketone and aldehyde components and simultaneous immobilization on the solid phase, introduction of substituents, grafts and derivatives compatible with the protection, detachment and restoration of active carbonyl reactivity, reaction of ketone library with malonate, reacting of the products with the aldehyde library in liquid phase and separation of the products by preparative HPLC.

The invention provides a preparation method of N-(2,4-fluorobenzoyl)-4-methoxyl-3-oxobutyrylamide. In the preparation method provided by the invention, Meldrum's acid is adopted as a raw material which is simple and easily available; moreover, the reaction process is short, the reaction conditions are mild, thus the preparation method is suitable for industrial and large-scale production of a Dolutegravir intermediate compound N-(2,4-fluorobenzoyl)-4-methoxyl-3-oxobutyrylamide.