Reduction to primary aromatic amino group, diazotization-coupling reaction

C-4 chiral carbon atom, pharmaceutical racemic

Nitro is oxidizing and oxidizes ferrous hydroxide into reddish brown iron oxide precipitate

Nimodipine and its tablets, dispersible tablets, capsules and soft capsules

The acetone solution of the drug reacts with NaOH to turn orange-red, and reacts with KOH to turn orange-yellow.

Nisoldipine, Nitrendipine and its preparations, Nifedipine and its preparations

It has the structure of 1,4-dihydropyridine, is alkaloid, and forms a precipitate with heavy metal salts.

Nimodipine HgCl → white precipitate

Nitrendipine bismuth potassium iodide → orange-red precipitation

Nicardipine hydrochloride Chromium ammonium thiocyanate → pink precipitate

The nitro group on the benzene ring is oxidizing and can be reduced to an aromatic primary amino group by zinc powder under acidic conditions.

ChP Nimodipine

BP, EP, JP nifedipine

Nitrendipine soft capsules

Nitrendipine tablets

ChP amlodipine besylate and its preparations, levamlodipine besylate and its preparations

BP nifedipine and its preparations, felodipine and its preparations, nimodipine tablets and intravenous solutions

EP felodipine, nifedipine

ChP except nitrendipine capsules

USP nifedipine and its preparations, isradipine and its preparations, nicardipine hydrochloride and its preparations, Felodipine and its preparations, amlodipine besylate and its preparations, nimodipine

BP lacidipine and its preparations, nifedipine preparations except capsules

ChP, US, BP, EP HPLC method Check oxidative degradation product impurity I, photodegradation product impurity II and related substances

JP TLC method to check photodegradable impurities II

Nifedipine HPLC method

USP, BP, EP, JP Basic impurity inspection Methyl aminobutenoate introduced during synthesis