3,4-Ethylidenedioxyamphetamine (EIDA) is a substituted derivative of 3,4-methylenedioxyamphetamine (MDA), which was developed by David Nichols and coworkers, in the course of research to determine the bulk tolerance around the benzodioxole portion of the MDA molecule. EIDA was found to produce similar effects to MDA in animals but with less than half the potency, while the isopropylidinedioxy derivative (IPIDA, IDA) did not substitute for MDA and instead had sedative and convulsant effects. This shows limited bulk tolerance at this position and (as with 2C-G-5) makes it likely the activity of EIDA will reside primarily in one enantiomer, although only the racemic mix has been studied as yet.
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^Nichols DE; Oberlender R; Burris K; Hoffman AJ; Johnson MP (November 1989). "Studies of dioxole ring substituted 3,4-methylenedioxyamphetamine (MDA) analogues". Pharmacology, Biochemistry, and Behavior. 34 (3): 571–6. PMID2623014. doi:10.1016/0091-3057(89)90560-1.
^Trachsel D; Hadorn M; Baumberger F (March 2006). "Synthesis of fluoro analogues of 3,4-(methylenedioxy)amphetamine (MDA) and its derivatives". Chemistry & Biodiversity. 3 (3): 326–36. PMID17193269. doi:10.1002/cbdv.200690035.