A short synthesis of argatroban: a potent selective thrombin inhibitor

Argatroban was synthesized in seven steps from 4-methylpiperidine. The condensation of (±)-trans-benzyl 4-methylpipecolic acid ester with Nα-Boc-Nω-nitro- -arginine led to two diastereomers that were separated. One of them is the precursor of argatroban.