Dichloroisoprenaline (DCI), also known as dichloroisoproterenol, was the first beta blocker ever to be developed. It is non-selective for the β1-adrenergic and β2-adrenergic receptors. DCI has low potency and acts as a partial agonist/antagonist at these receptors.[1]

Although DCI was of no clinical value itself, further developments from DCI eventually led to the development of the clinical candidate pronethalol (withdrawn due to carcinogenicity) and subsequently propranolol (the first clinically successful beta blocker).

Dichloroisoprenaline is a racemic mixture of enantiomers.

The two enantiomers of dichloroisoprenaline

References

  1. ^ W. E. Glover; A. D. M. Greenfield; R. G. Shanks (October 1962). "Effect of dichloroisoprenaline on the peripheral vascular responses to adrenaline in man". Br J Pharmacol Chemother. 19 (2): 235–244. doi:10.1111/j.1476-5381.1962.tb01185.x. PMC 1482134. PMID 13948521.