Substituted benzofuran

The substituted benzofurans are a class of chemical compounds based on the heterocyclic and polycyclic compound benzofuran. Many medicines use the benzofuran core as a scaffold, but most commonly the term is used to refer to the simpler compounds in this class which include numerous psychoactive drugs, including stimulants, psychedelics and empathogens. In general, these compounds have a benzofuran core to which a 2-aminoethyl group is attached, and combined with a range of other substituents. Some psychoactive derivatives from this family have been sold under the name Benzofury.

Use and effects

Benzofurans like 5-APB and 6-APB are said to have relatively minor psychedelic effects.

Pharmacology

Pharmacodynamics

Benzofurans like 5-APB and 6-APB act as serotonin–norepinephrine–dopamine releasing agents and as serotonin 5-HT₂ receptor agonists. In addition, some benzofurans, including 5-MAPB, 6-MAPB, BK-5-MAPB, and BK-6-MAPB, have unexpectedly been found to be potent serotonin 5-HT_1B receptor agonists. Along with serotonin release and other actions, this property may be involved may be involved in their entactogenic effects. Conversely, MDMA is much less potent as an agonist of the serotonin 5-HT_1B receptor.

History

The 2,3-dihydrobenzofurans 5-APDB and 6-APDB were described by David E. Nichols and colleagues at Purdue University as MDMA analogues in 1993. Subsequently, the benzofurans 5-APB and 6-APB emerged as novel designer drugs in 2010. Prior to this, they had been patented by Eli Lilly and Company as serotonin 5-HT_2C receptor agonists for potential treatment of eating disorders and seizures in 2000 and 2006. 5-APB and 6-APB are often confused with 5-APDB and 6-APDB. The pharmacology of various benzofurans and 2,3-dihydrobenzofurans was further clarified in the mid-2010s and thereafter.

Society and culture

Legal status

Substituted benzofurans saw widespread use as recreational drugs by being sold as research chemicals making them exempt from drug legislation. Many of the more common compounds were banned in the UK in June 2013 as temporary class drugs, while others have been made permanently illegal in various jurisdictions.

List of substituted benzofurans

The derivatives may be produced by substitutions at six locations of the benzofuran molecule, as well as saturation of the 2,3- double bond.
The following table displays notable derivatives that have been reported:

Structure	Compound	CAS #	R₂	R₃	R₄	R₅	R₆	R₇	Other
	2-APB	30455-73-3	2-aminopropyl	H	H	H	H	H	-
	2-MAPB	806596-15-6	2-propyl	H	H	H	H	H	-
	2-EAPB		2-propyl	H	H	H	H	H	-
	2-MABB		2-butyl	H	H	H	H	H	-
	BPAP	260550-89-8	2-pentyl	H	H	H	H	H	-
	3-F-BPAP	501901-68-4	2-pentyl	H	H	H	H	H	-
	Brofaromine	63638-91-5	4-piperidinyl	H	H	methoxy	H	bromo	-
	3-APB	105909-13-5	H	2-aminopropyl	H	H	H	H	-
	O-DMT		H	2-ethyl	H	H	H	H	-
	Dimemebfe	140853-58-3	H	2-ethyl	H	methoxy	H	H	-
	Mebfap	140853-59-4	H	2-aminopropyl	H	methoxy	H	H	-
	5-MeO-DiBF		H	2-ethyl	H	methoxy	H	H	-
	MiPBF		H	2-ethyl	H	H	H	H	-
	4-APB	286834-82-0	H	H	2-aminopropyl	H	H	H	-
	DOB-5-HEMIFLY		H	H	2-aminopropyl	methoxy	H	bromo	2,3-dihydro
	5-APB	286834-81-9	H	H	H	2-aminopropyl	H	H	-
	5-MAPB	1354631-77-8	H	H	H	2-propyl	H	H	-
	5-EAPB	1445566-01-7	H	H	H	2-propyl	H	H	-
	5-APB-NBOMe		H	H	H	2-propyl	H	H	-
	6-APB	286834-85-3	H	H	H	H	2-aminopropyl	H	-
	6-MAPB	1354631-79-0	H	H	H	H	2-propyl	H	-
	6-EAPB	1632539-47-9	H	H	H	H	2-propyl	H	-
	5-AEDB		H	H	H	2-aminoethyl	H	H	2,3-dihydro
	5-APDB	152624-03-8	H	H	H	2-aminopropyl	H	H	2,3-dihydro
	5-MAPDB	1354631-78-9	H	H	H	2-propyl	H	H	2,3-dihydro
	5-EAPDB		H	H	H	2-propyl	H	H	2,3-dihydro
	6-APDB	1354631-78-9	H	H	H	H	2-aminopropyl	H	2,3-dihydro
	6-MAPDB	1354631-81-4	H	H	H	H	2-propyl	H	2,3-dihydro
	6-EAPDB		H	H	H	H	2-propyl	H	2,3-dihydro
	bk-5-MAPB		H	H	H	1-oxo-2-propyl	H	H	-
	bk-6-MAPB		H	H	H	H	1-oxo-2-propyl	H	-
	5-MBPB		H	H	H	2-butyl	H	H	-
	6-MBPB		H	H	H	H	2-butyl	H	-
	5-DBFPV	2117405-32-8	H	H	H	1-oxo-2-pentyl	H	H	2,3-dihydro
	6-MeO-5-APDB		H	H	H	2-aminopropyl	methoxy	H	2,3-dihydro
	F	99355-77-8	H	H	H	methoxy	2-aminopropyl	H	2,3-dihydro
	F-2	99355-74-5	methyl	H	H	methoxy	2-aminopropyl	H	2,3-dihydro
	F-22	952016-51-2	dimethyl	H	H	methoxy	2-aminopropyl	H	2,3-dihydro
	7-APB	286834-86-4	H	H	H	H	H	2-aminopropyl	-
	DOI-2-HEMIFLY		H	H	iodo	methoxy	H	2-aminopropyl	2,3-dihydro
	Amiodarone	1951-25-3	propyl	3,5-diiodo-4-benzoyl	H	H	H	H	-
	2C-B-FLY	733720-95-1	H	H	2-aminoethyl	5,6-dihydrofuro	-	bromo	2,3-dihydro
	2C-B-DRAGONFLY	260809-98-1	H	H	2-aminoethyl	furo	-	bromo	-
	2C-C-FLY	1354633-83-2	H	H	2-aminoethyl	5,6-dihydrofuro	-	chloro	2,3-dihydro
	2C-I-FLY	1354633-88-7	H	H	2-aminoethyl	5,6-dihydrofuro	-	iodo	2,3-dihydro
	2C-D-FLY	1354634-07-3	H	H	2-aminoethyl	5,6-dihydrofuro	-	methyl	2,3-dihydro
	2C-E-FLY		H	H	2-aminoethyl	5,6-dihydrofuro	-	ethyl	2,3-dihydro
	2C-EF-FLY		H	H	2-aminoethyl	5,6-dihydrofuro	-	2-fluoroethyl	2,3-dihydro
	2C-T-7-FLY	1354633-05-8	H	H	2-aminoethyl	5,6-dihydrofuro	-	n-propylthio	2,3-dihydro
	2C-MeTriox		H	H	2-aminoethyl	5,6-methylenedioxy	-	methyl	2,3-dihydro
	MeTriox		H	H	2-aminopropyl	5,6-methylenedioxy	-	methyl	2,3-dihydro
	DOB-FLY	219986-75-1	H	H	2-aminopropyl	5,6-dihydrofuro	-	bromo	2,3-dihydro
	Bromo-DragonFLY	502759-67-3	H	H	2-aminopropyl	furo	-	bromo	-
	DOB-2-DRAGONFLY-5-BUTTERFLY	1043541-82-7	H	H	2-aminopropyl	5,6-dihydropyrano	-	bromo	-
	DOM-FLY	748748-08-5	H	H	2-aminopropyl	5,6-dihydrofuro	-	methyl	2,3-dihydro
	DOMOM-FLY		H	H	2-aminopropyl	5,6-dihydrofuro	-	methoxymethyl	2,3-dihydro
	2C-B-FLY-NBOMe	1335331-42-4	H	H	2-ethyl	5,6-dihydrofuro	-	bromo	2,3-dihydro
	2C-B-DRAGONFLY-NBOH	1335331-45-7	H	H	2-ethyl	furo	-	bromo	-
	TFMFly	780744-19-6	H	H	2-aminopropyl	5,6-dihydrofuro	-	trifluoromethyl	2,3-dihydro
	Mescaline-FLY		H	H	2-aminoethyl	5,6-dihydrofuro	-	methoxy	2,3-dihydro
	YM-348	372163-84-3	ethyl	H	1--pyrazol	-	H	H	-
	2-Desethyl-YM-348	748116-94-1	H	H	1--pyrazol	-	H	H	-