摘要:
A tetrahydroprotoberberine quaternary ammonium compound represented by the formula: ##STR1## wherein R.sub.1, R.sub.2, R' and X are as defined in the specification. A method of preparing the compound is provided. The compounds can suppress arrhythmia and ventricular fibrillation, protect against myocardial ischemia, and can be conveniently orally administered.