Cinepazide

Cinepazide was discovered by scientists at Laboratoires Delalande (now part of Sanofi) in 1969 in an effort to explore useful substituted cinnamoyl-piperazine compounds.[6][7] The drug, in the form of a pill taken orally, was launched by Delalande in 1976 under the tradename Vasodistal, for treatment of heart failure, balance disorders, cerebrovascular disease, and vascular complications of diabetes.[6][8] In 1988 the drug was withdrawn from the market in Spain due to risk of agranulocytosis; other countries where the drug was available added warnings to the label.[9][10] It was withdrawn from the market in France in 1992.[11] The drug had also been marketed in Japan by Daiichi Pharmeceutical Company under the brand name "Brindel"[2] for dementia, but was withdrawn in 1999, following a review by the Japanese regulatory authorities of dementia drugs after a drug, calcium hopantenate, that had been considered the standard of care and against which cinepazide and other dementia drugs had been compared, had failed to demonstrate efficacy in a re-evaluation.[12]

In 2002 Sihuan Pharmaceutical brought an injectable form of the drug to market in China;[13] Sihuan had acquired the drug from a military hospital in China that had developed the formulation.[14] In 2010 it was the highest selling drug in China, with about 1 billion RMB in sales in the 3rd quarter, outselling Plavix in China.[13][3] This made Sihuan Pharm the largest company in China in the cardio-cerebral vascular drug market in 2010.[3] In 2014 it was the tenth highest-selling drug in China.[14]

Thieme Synthesis:[15][16] Background patent:[17] Sino:[18]

Amide formation between chloroacetyl chloride (1) and pyrrolidine (2) gives 1-(chloroacetyl)pyrrolidine [20266-00-6] (3). Displacement of the remaining halogen by piperazine gives 1-(pyrrolidinocarbonylmethyl)piperazine [39890-45-4] (4). A second Schotten-Baumann reaction this time with 3,4,5-trimethoxycinnamoyl chloride [4521-61-3] (5) completed the synthesis of cinepazide (6).