84598-98-1

Upstream product

• 17040-70-9 cis-3,5-dibromocyclopentene 
• 3784-04-1 potassium 2,4,6-tribromophenoxide 
• 118-79-6 2,4,6-tribromophenol 
• 77-73-6 dicyclopentadiene 
• 542-92-7 cyclopenta-1,3-diene 
• 142-29-0 cyclopentene 
• 1890-04-6 3,5-cis-dibromocyclopentene 

Downstream Products

• 88277-10-5 (+/-)-3a,8b-cis-dihydro-3H-5-carboxy-7-bromocyclopenta[b]benzofuran 
• 88277-50-3 (-)-3a,8b-cis-dihydro-3H-5-carboxy-7-bromocyclopenta[b]benzofuran 
• 88430-50-6 (±)-(1R,2R,3aS,8bS)-2,3,3a,8b-tetrahydro-2-hydroxy-1-[(E)-(3S,4RS)-3-hydroxy-4-methyl-1-octen-6-ynyl]-1H-cyclopenta[b]-benzofuran-5-butanoic acid 

Relevant academic research and scientific papers

Synthesis method of beraprost sodium intermediate

The invention relates to a synthesis method of a Beraprost sodium intermediate (III). Cyclopentene and N-bromo-succinimide (NBS) carry out free radical reaction to obtain dibromocyclopentene; and dibromocyclopentene reacts with 2,4,6-tribromophenol to directly generate 3,5-bis(2,4,6-tribromophenoxyl) cyclopentene (compound I) through a one-pot method. Then through Grignard reactions, a compound (I) and a compound (II) are obtained. N-bromo-succinimide and a commercial product namely cyclopentene are taken as the raw materials to synthesize dibromocyclopentene, 170 DEG C cracking and ultralow temperature reactions (-40 to -30 DEG C) are avoided, the using of bromine is also avoided, the reaction conditions are milder, and the synthesis method is more environmentally friendly and is convenient for industrial production.

Synthesis of 5,6,7-trinor-4,8-inter-m-phenylene PGI2 and Beraprost

We have disclosed a new class of stable PGI2 analogue, 5,6,7-trinor- 4,8-inter-m-phenylene PGI2 which has a phenyl ether moiety instead of enol- ether skeleton in PGI2. The m-phenylene PGI2 and its derivative (Betaprost) were synthesized via dihydrocyclopenta[b]benzofuran derivatives as key intermediates by ortho-selective metal-halogen exchange reaction with Grignard reagents and subsequent copper-catalyzed cyclization. The ω-side chains were introduced by stereoselective epoxide formation or Prins reaction.

Synthesis of (+)-5,6,7-trinor-4,8-inter-m-phenylene PGI2

The titled compound, which is a stable and potent analog of prostacyclin, was synthesized from readily available 1,4-dibromocyclopentene via cyclopenta[b]benzofuran carboxylic acid 5.