1,3-Benzodioxolylbutanamine (also known as 3,4-methylenedioxybutanphenamine, MDB, BDB, J, and 3,4-methylenedioxy-α-ethylphenethylamine) is an entactogenic drug of the phenethylamine, amphetamine, and phenylisobutylamine families.

Although pleasant and euphoric, BDB is also fairly sedating and some users feel that the lack of stimulant effect makes it less enjoyable than other similar drugs.

Additional side effects associated with BDB include nystagmus and dizziness.

Animal studies and anecdotal reports show that BDB is a slightly more potent serotonin releasing agent than its methylated sister compound methylbenzodioxylbutanamine (MBDB; "Eden", "Methyl-J").

[4] However, it is more commonly known as a metabolite of the N-alkylated analogues MBDB and ethylbenzodioxylbutanamine (EBDB; "Ethyl-J") which have appeared in methylenedioxymethamphetamine (MDMA; "Ecstasy", "Adam", "Empathy", "Molly", "E", "X", "XTC") tablets.