FUB-AKB48 (also known as FUB-APINACA, 5F-AKB48 , 5F-APINACA) is a synthetic designer cannabinoid that acts as a potent agonist for the CB1 and CB2 cannabinoid receptors.
It produces subjective effects somewhat similar to that of cannabis with a short duration and an emphasis on intense physical sensations. Its metabolism has been described in the scientific literature. It was first identified in South Korea and is available for sale as a grey area research chemical through online vendors.
Cannabinoids are commonly smoked or vaporized to achieve a quick onset of effects and rapid offset. 5F-AKB48 is orally active when dissolved in a lipid, which can increase the duration significantly. Like other cannabinoids, it is insoluble in water but dissolves in ethanoland lipids.
Unlike cannabis, the chronic abuse of synthetic cannabinoids has been associated with multiple serious injuries deaths and more dangerous side effects and toxicity in general. Therefore, it is strongly discouraged to take this substance for extended periods of time or in excessive doses.
5F-AKB48, or N-(adamantan-1-yl)-1-(5-fluoropentyl)-1H-indazole-3-carboxamide, is a synthetic indazole cannabinoid as it contains a substituted indazole group. This indazole moeity is substituted at R1 with a fluoropentyl chain, a substitution shared with 5F-PB-22. Additionally, the indazole is substituted at R3 with a carboxamide group. This carboxamide group is N-substituted at its terminal amine group with an adamantane group. This group consists of four fused cyclohexane rings in a unique structure called a diamondoid. 5F-AKB48 is an analog of STS-135 in which the core indole structure is substituted with an indazole base.
Although this substance has not been formally studied, from analysis of the structure, it is presumed that 5F-AKB48 has a similar binding profile to that of other cannabinoids and matches many of the in vivo properties of Δ9-THC. However, the role of these interactions and how they result in the cannabinoid high continues to remain elusive.