765915-89-7

Upstream product

• 2719-27-9 cyclohexanylcarbonyl chloride 
• 60567-64-8 (1R)-(-)-1-aminomethyl-1,2,3,4-tetrahydroisoquinoline 
• 64-04-0 phenethylamine 
• 850130-96-0 2-(4-methoxyphenyl)-1-(nitromethyl)-1,2,3,4-tetrahydroisoquinoline 
• 60567-40-0 N-((1,2,3,4-tetrahydro-1-isoquinolinyl)methyl)acetamide 
• 151004-93-2 (R)-1,2,3,4-tetrahydroisoquinoline-1-carboxylic acid 
• 151004-96-5 (1R)-2-[(tert-butyl) oxycarbonyl]-1,2,3,4-tetrahydroisoquinoline-1-carboxylic acid 
• 954239-58-8 (1R)-1-hydroxymethyl-2-[(tert-butyl) oxycarbonyl]-1,2,3,4-tetrahydroisoquinoline 
• 41034-52-0 1,2,3,4-tetrahydroisoquinoline-1-carboxylic acid 
• 88422-83-7 2-(3,4-dihydro-1-isoquinolinylmethyl)-1H-isoindole-1,3(2H)-dione 
• 40615-08-5 [(isoquinolin-1-yl)methyl]amine 
• 1198-30-7 1-isoquinolinecarbonitrile 
• 79848-93-4 N-(1,2,3,4-tetrahydroisoquinolin-1-ylmethyl)cyclohexanecarboxylic acid amide 
• 78317-83-6 2-(4-methoxyphenyl)-1,2,3,4-tetrahydroisoquinoline 

Downstream Products

• 135526-78-2 (-)-Praziquantel 

Relevant academic research and scientific papers

METHOD FOR THE PRODUCTION OF PRAZIQUANTEL AND PRECURSORS THEREOF

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.

METHOD FOR THE PRODUCTION OF PRAZIQUANTEL AND PRECURSORS THEREOF

The present invention relates to methods for the production of enantiopure or enantioenriched Praziquantel precursors and to methods for the production of enantiopure or enantioenriched Praziquantel comprising the methods for the production of the Praziquantel precursors. The present invention further relates to compounds or intermediates useful in such methods.

CRYSTAL FORM OF (R)-PRAZIQUANTEL AND PREPARATION METHOD AND APPLICATION THEREOF

The present invention relates to a crystal form of (R)-praziquantel and a preparation method and uses thereof. The X-ray diffraction pattern (CuKα radiation) of the crystal form of (R)-praziquantel at 25° C. shows the following diffraction peaks: 2-Theta=

Enhancing the usefulness of cross dehydrogenative coupling reactions with a removable protecting group

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.

Enantioselective synthesis of (R)-(-)-praziquantel (PZQ)

Praziquantel 8 (2-cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino[2,1-a]isoquinoline-4-one), a powerful anti-worm drug, has been synthesized in its enantiopure form via asymmetric transfer hydrogenation according to the Noyori protocol. Initially, the reduction of prochiral imine 4 afforded product 5 in 62% ee, but a single crystallization amplified the enantiomeric purity to 98% ee. The final (R)-(-)-praziquantel 8 was prepared in three subsequent steps in 56% chemical yield.

Total synthesis of (-)-praziquantel: An anthelmintic drug

The optically pure (-)-praziquantel was synthesised using phenylethylamine as starting material in 12% overall yield. The key step was achived by a chiral auxiliary mediated Pictet-Spengler reaction.