Alcuronium. One of the most beautiful looking NMB molecules.

Allyl group

An allyl group.


Alcuronium is the single synthetic derivative of toxiferine. It is a medium duration non-depolarizing neuromuscular blocking agent with the chemical formula C44H50N4O2

The main difference between alcuronium and toxiferine is that alcuronium has two allyl groups, one group bonded to each quaternary ammonium, hence the name ALcuronium. It is sometimes also called "alloferin" and also "diallyltoxiferine," which is literally what it is.

Allyl groups attached to the quaternary ammoniums of NMB compounds seem to make them less potent or of shorter duration. Rocuronium and rapacuronium are the least potent of the steroid structured NMBs, and both of them also have an allyl group.