Corydine is a naturally occurring alkaloid which can be extracted from plants such as Croton echinocarpus leaves. Corydine is efficient on inhibiting reverse transcriptase (RT) activity with an IC50 of 356.8 μg/mL. Corydine displays significant in vitro anti-HIV potential, inhibiting 40% of the HIV-1 reverse transcriptase enzyme activity at a concentration of 450 μg/mL of Corydine.