79848-93-4Relevant academic research and scientific papers
Preparation method of praziquantel
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, (2022/03/27)
The invention relates to the technical field of medical intermediates, and provides a praziquantel preparation method which comprises the following steps: S1, adding isoquinoline, cyanide, tetrabutylammonium bromide and dichloroethane into a reactor, and dropwise adding benzoyl chloride for reaction to obtain a first-step product; s2, performing catalytic hydrogenation on the first-step product to obtain a second-step product; and S3, adding ethyl acetate into the second-step product, stirring and dissolving, adding sodium bicarbonate, dropwise adding chloroacetyl chloride, stirring and reacting to obtain a praziquantel crude product, and recrystallizing to obtain praziquantel. Through the technical scheme, the problems of long reaction process, high energy consumption and low yield in the prior art are solved.
Aza-Henry Reaction with Nitrones, an Under-Explored Transformation
Messire, Gatien,Massicot, Fabien,Vallée, Alexis,Vasse, Jean-Luc,Behr, Jean-Bernard
, p. 1659 - 1668 (2019/02/19)
Nitromethylation of nitrones occurred efficiently in CH3NO2 in the presence of tetramethylammonium fluoride or triazabicyclodecene as promoters. The obtained adducts might be conveniently transformed into vicinal diamines. The process was extended to nitroethane and nitropropane affording mixtures of syn and anti stereoisomers with low diastereoselectivity.
HETEROCYCLIC COMPOUNDS AND USE THEREOF
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Paragraph 0060-0061, (2019/03/30)
Disclosed are compounds of formula (I) below or pharmaceutically acceptable salts thereof: in which each of variables R1-R6, L, m, and n is defined herein. Also disclosed are a method for treating an opioid receptor-associated condit
HETEROCYCLIC COMPOUNDS AND USE THEREOF
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Paragraph 0061, (2019/07/23)
Disclosed are compounds of formula (I) below or pharmaceutically acceptable salts thereof:in which each of variables R 1 -R 6 , L, m, and n is defined herein. Also disclosed are a method for treating an opioid receptor-associated condition with a compound
METHOD FOR THE PRODUCTION OF PRAZIQUANTEL AND PRECURSORS THEREOF
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, (2017/03/21)
The present invention provides methods of preparing Praziquantel, in particular (R)-Praziquantel and analogues thereof in a stereoselective manner. One method involves asymmetric hydrogenation of the following intermediate compound (I) and subsequent cyclization.
Approach to Isoindolinones, Isoquinolinones, and THIQs via Lewis Acid-Catalyzed Domino Strecker-Lactamization/Alkylations
Dhanasekaran, Sivasankaran,Suneja, Arun,Bisai, Vishnumaya,Singh, Vinod K.
supporting information, p. 634 - 637 (2016/03/01)
A one-pot, three-component synthesis of widely substituted isoindolinones and isoquinolinones, featuring a Lewis acid-catalyzed efficient Strecker reaction and lactamization sequence, affording products in good to high yields is reported. The method has also been extended to the synthesis of tetrahydroisoquinolines (THIQs) in high yields. (Chemical Equation Presented).
Enhancing the usefulness of cross dehydrogenative coupling reactions with a removable protecting group
Tsang, Althea S.-K.,Ingram, Katrin,Keiser, Jennifer,Hibbert, D. Brynn,Todd, Matthew H.
, p. 4921 - 4924 (2013/08/23)
A removable protecting group has been identified that allows the products of widely-used cross dehydrogenative couplings to be synthetically elaborated. The method can be used with enantiopure amines with no loss of enantiomeric excess. The methodology is exemplified by a new synthesis of enantiopure praziquantel, the drug used in the treatment of millions of people suffering from the neglected tropical disease, schistosomiasis.
Synthesis of new praziquantel analogues: Potential candidates for the treatment of schistosomiasis
Sadhu, Partha Sarathi,Kumar, Singam Naveen,Chandrasekharam, Malapaka,Pica-Mattoccia, Livia,Cioli, Donato,Rao, Vaidya Jayathirtha
, p. 1103 - 1106 (2012/03/11)
An efficient synthesis of antischistosomal drug praziquantel and analogues was achieved and the synthetic route designed was to afford structurally diverse analogues for better structure-activity relationship understanding. Total of nineteen PZQ analogues with structural variations at amide, piperazine and aromatic moieties have been synthesized and fully characterized. Among all the new analogues tested for antischistosomal activity, one dimethoxy tetrahydroisoquinoline analogue and two tetrahydro-β-carboline analogues exhibited moderate activity against adult Schistosoma mansoni. Tetrahydro-β-carboline analogues showed moderate activity whereas the presence of p-trifluoromethylbenzoyl and p-toluenesulphonyl moieties resulted in complete suppression of antischistosomal activity.
