- A preparation method for rosacea acetate hydrochloride
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The present invention relates to the field of pharmaceutical preparation technology, in particular to a method for preparing rosatidine acetate hydrochloride. The present invention adopts m-hydroxybenzoic acid as a starting material, a wide range of sources, inexpensive, and it can be prepared by oxidation of m-hydroxytoluene, without involving a toxicity warning structure and nitrosamine impurities; at the same time, in this preparation process only involves a genotoxic warning structure substance, reducing the risk of medication of subsequent drugs.
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- Preparation method of high-purity medicinal roxatidine acetate hydrochloride
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The invention discloses a preparation method of high-purity medicinal roxatidine acetate hydrochloride, and relates to the field of medicine synthesis. The invention provides the preparation method ofthe medicinal roxatidine acetate hydrochloride which is simple in production process, high in safety coefficient, low in cost, high in yield and extremely low in impurity content. The method comprises the following steps: 1) preparing 3-piperidine methylphenol; (2) preparing N-[3-(3-aminopropoxy)-benzyl] piperidine from the 3-piperidine methylphenol obtained in the step (1); and (3) preparing theroxatidine acetate hydrochloride by adopting the N-[3-(3-aminopropoxy)-benzyl] piperidine in the step (2). The yield of the roxatidine acetate hydrochloride prepared by the method disclosed by the invention can reach 87%, and the purity can reach 99.45%. The method is applied to the field of medicine synthesis.
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- Preparation method of roxatidine acetate hydrochloride
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The invention relates to a preparation method of roxatidine acetate hydrochloride. The preparation method comprises the following steps: step 1, dissolving m-cresol and 3-chloropropylamine hydrochloride into a reaction solvent according to a certain ratio, carrying out a reaction in the presence of an alkali, extracting after the reaction, and concentrating after simple purification to obtain an intermediate 1; 2, dissolving the intermediate 1 and an alkali in a reaction solvent according to a certain ratio, adding acetoxyacetyl chloride in a dropwise manner at a low temperature, and extracting and concentrating after the reaction of the intermediate 1 is finished to obtain an intermediate 2; 3, carrying out a bromination reaction on the intermediate 2 and N-bromosuccinimide, and directlycarrying out water washing extraction to obtain an intermediate 3; 4, carrying out a reaction on the intermediate 3 and excessive piperidine in a solvent, concentrating, extracting with dichloromethane, drying, and further purifying with acetic anhydride to obtain roxatidine acetate; 5, dissolving the intermediate 3 in acetone, adding hydrochloric acid in a dropwise manner to form a salt, filtering, and drying; and 6, mixing with absolute ethyl alcohol, filtering, carrying out cooling crystallization, and drying to obtain the roxatidine acetate hydrochloride.
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- Novel preparation method of intermediate namely 3-(1-piperidine methyl)phenol of roxatidine acetate hydrochloride
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The invention relates to a preparation method of an intermediate namely 3-(1-piperidine methyl)phenol of roxatidine acetate hydrochloride. M-nitrobenzaldehyde is taken as the primary raw material; under the effect of a phase transfer catalyst, m- nitrobenzaldehyde is reduced by metal borohydride to obtain corresponding benzyl alcohol; in the presence of an alkali, benzyl alcohol reacts with organic sulfonyl chloride to generate active organic sulfonate; then in the presence of an alkali, organic sulfonate carries out N-alkylation reactions with piperidine to generate N-substituted piperidine derivatives; reducing the nitro groups of N-substituted piperidine derivatives to obtain corresponding amino compounds; and subjecting the amino compounds to diazotization, hydrolysis, and alkalizationin a sulfuric acid water solution to obtain 3-(1-piperidine methyl)phenol. The problem that the supply of the conventional raw material (m-hydroxyl benzaldehyde) is not enough and the cost is greatlyincreased is solved. The method is simple and safe, the raw materials are cheap and easily available, the reaction yield is high, and the method is very suitable for industrial production of 3-(1-piperidine methyl)phenol.
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- Preparation method of roxatidine acetate hydrochloride
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The invention discloses a preparation method of roxatidine acetate hydrochloride. The preparation method is characterized by adopting m-hydroxybenzaldehyde and piperidine as raw materials for carrying out chemical synthesis under the conditions of microwave radiation and high frequency ultrasonic wave, so that the product yield is improved, the reaction time is shortened, the cost is reduced, the product purity is improved, the total impurities are reduced, and an ideal effect is achieved.
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- A new synthesis of roxatidine acetate
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A new four-step synthesis of N-{3-[3-(1-piperidinylmethyl)- phenoxy]propyl}acetoxyacetamide hydrochloride has been performed. The key aralkyl ether was synthesized in high yield under moderate conditions. A suitable scaling up permits a bulky production of the drug in 98.5% purity.
- Tarpanov, Velichko,Vlahov, Radoslav,Penkov, Miho,Krikorian, Dikran,Parushev, Stoyan,Mechkarova, Pepa,Angelova, Nely,Schunack, Walter
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