Manidipine

Manidipine is a calcium channel blocker (dihydropyridine type) that is used clinically as an antihypertensive.

It was patented in 1982 and approved for medical use in 1990.

Synthesis
The alkylation between N-(2-hydroxyethyl)piperazine [103-76-4] (1) and Benzhydryl Bromide [776-74-9] (2) gives 2-(4-benzhydrylpiperazin-1-yl)ethanol [10527-64-7] (3). The reaction with Diketene [674-82-8] (4) gives 2-(4-benzhydryl-1-piperazinyl)ethyl acetoacetate [89226-49-3] (5). The reaction with 3-nitrobenzaldehyde [99-61-6] (6) and Methyl 3-aminocrotonate [14205-39-1] (7) completed the synthesis of Manidipine (8).