Isolation and structure elucidation of the major photodegradation products of pirmenol hydrochloride.
Column chromatography, thin-layer chromatography, high-performance liquid chromatography, nuclear magnetic resonance spectrometry, and high-resolution mass spectrometry were employed to separate and identify the photodegradation products of pirmenol hydrochloride [(+/-)-cis-alpha-[3-(2,6-dimethyl-1-piperidinyl)propyl]-alpha-phenyl-2- pyridinemethanol monohydrochloride monohydrate], a new antiarrhythmic drug. A methanol solution of pirmenol was irradiated using a low-pressure mercury lamp. The solution afforded four major degradation products, three of which were identified as 3-(cis-2,6-dimethylpiperidinyl)propyl 2-(2-pyridyl)phenyl ketone, 2-(2-pyridyl)benzoic acid, and methyl 2-(2-pyridyl)-benzoate. The degradation followed apparent-first-order reaction kinetics. In addition, the possible photodegradation pathways are discussed with reference to reaction mechanisms.
Sakano
I
I
Parke-Davis Research Laboratory, Warner-Lambert K.K., Kanagawa, Japan.
Ishii
T
T
Ichikawa
S
S
Harasawa
K
K
Minohara
K
K
Yamamura
S
S
Nishiyama
S
S
D000889:Anti-Arrhythmia Agents / Q000737:chemistry* / Q000528:radiation effects; D002855:Chromatography, Thin Layer; D007700:Kinetics; D008027:Light; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010777:Photochemistry; D010880:Piperidines / Q000737:chemistry* / Q000528:radiation effects; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet
D000889:Anti-Arrhythmia Agents; D010880:Piperidines; C024318:pirmenol