Methadone analogues with longer half lives

[erosion]

Alexander Shulgin states in his "Drugs of Abuse in the Future"

On Methadone Molocule modification:
"A third area of morphine-like activity has been found with substitution upon the nitrogen atom of methadone. A series of 4,4-gemdisubstituted piperidinyl analogs have been found [6J to be some 1500 times as potent as methadone, and to be quite a bit longer acting. There are no studies of these chemicals in humans, but there is certainly represented here a rich area of potential chemical exploration."

My question is, does anymone know more about this? Were any chemicals made that didn't meet with FDA approval? Think of a methadone maintainance with fewer dosings. Why wasn't this explored more?

Source:
Future Drugs of Abuse
Alexander Shulgin
Clin. Toxicol. 8(4), 405-456 (1975)

https://www.synthetikal.com/Rhodiums_pdfs/chemistry/shulgin.futuredrugs.html

 

[BilZ0r]

Why wasn't it explored? Probably because of a lack of finanical insentive. I'm sure methadone is pretty cheap.

 

[Smyth]

C6H6 posted the answer on the OD board the other day. The structure is weird and it is strange that anyone would have thought of it. Basically it is dipipanone where the 4-position on the piperidine ring is further substituted with a fused spirocyclohexyl-3,4-benzene ring. An interesting concept to say the least if not a bit far-fetched.