- Source: Monatepil
Monatepil is a calcium channel blocker and α1-adrenergic receptor antagonist used as an antihypertensive.
Synthesis
The synthesis of monatepil was first disclosed in patents filed by Dainippon Pharmaceutical.
The amino group of the dihydrodibenzothiepin (1) is first reacted with the acid chloride of 4-chlorobutyric acid, to give the amide (3). This is then used to alkylate para-fluorophenylpiperazine (4) to yield monatepil.