βk-5-MAPB, or BK-5-MAPB, is an entactogen of the benzofuran and cathinone groups which is related to both 5-MAPB and methylone.

It was patented by Matthew Baggott and Tactogen and is under investigation by Tactogen for potential medical use.

[1][2][3][4] It acts as a monoamine releaser with selectivity for serotonin and has a similar potency to MDMA.

[3] In rodent drug discrimination tests, (S)-βk-5-MAPB fully substitutes for MDMA whereas (R)-βk-5-MAPB partially substitutes for MDMA and dextroamphetamine at different doses, (R)-βk-5-MAPB and (S)-βk-5-MAPB both generalize to dextroamphetamine, and (S)-βk-5-MAPB but not (R)-βk-5-MAPB substitutes for DOM.

[4] In other tests, both (S)-βk-5-MAPB and (R)-βk-5-MAPB showed stimulant-like pro-impulsive effects, but (S)-βk-5-MAPB was more potent than (R)-βk-5-MAPB.