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Semorphone - a substitute for maintenance treatment?

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Bluelighter
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Mar 28, 2006
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Semorphone is a partial agonist at mu opioid receptors. Its nociceptive value is about 2 times as morphine. I wonder if it would be a good substitute for methadone or buprenorphine specifically. I assume it has poor oral bioavailability just at any N-substituted oxymorphone derivatives so when this would come in powder it would have to be injected or given rectally. If it turned out to be a good substitute in trials, they could make sublingual tablets.

Anyway, so far this drug is not in use but it's known it doesn't produce any toxic effects from available research. I'm looking for some substitute as I'm running out of buprenorphine and I don't want to use any false prescriptions for buprenorphine transdermal patches (their matrix is in foil, there is no liquid inside, so they make perfect for sublingual use).

Does anyone have any further more in-deep information about this drug? I know doses with 100% bioavailability may have to be ~60-80mg for my addiction right now. :(
 
Interesting.
Ive got 2 questions.
1-Do u have any information regarding the duration/half life of this drug. One of the most important criteria for a maintenance drug is having a very long duration/half life. You ideally want something that you can just take once (perhaps twice a day) and be held for the whole day and through the night (the through the night thing is esp. important as u dont want to be waking up in the middle of the night to dose, or wake up in withdrawal every morning). And for the record, from the look of this thing, I highly doubt it would have a very long half life.

The 2nd issue is if this drug would be considered an analogue of oxymorphone. Semorphone is not specifically scheduled, nor is it currecntly used in medicine. This means the only way you could get a hold of this stuff is to have a company synth this for u (or synth it urself if u have the capabilities). The problem is, is that if this would fall under the analogue act, you really dont want to get involved in this. Having an overseas company snyth u a bunch of bulk narcotic that could be deemed every bit as illegal as oxymorphone is not a good idea.

SOrry to burst ur bubble, but I just dont think this is a good idea.-DG
 
Yeah, it's an obvious analogue.

The law does say "substantially similar effects" and this is a partial agonist, but there are plenty of scheduled partial agonists that this would be called an analogue of (buprenorphine, for example).
 
It's an analog of oxymorphone easily obtained in synthesis if someone has pure oxymorphone and knows how to put there that 2-methoxyethyl group instead of methyl (not one step, but I understand the rule 'no syntheses').

I experimented just to be sure despite the fact that the structure gives away more or less suspected time of action etc.

I can tell from my experiences with this drug that it is not suitable for a substitute that could be given once a day or twice a day. Although 100mg of semorphone hydrochloride seemed to wipe away W/D (I was at 140-160mg of morphine sulfate twice a day), it turned out to be very short-lived and it couldn't be used in the same manner as buprenorphine unless some ER formula would be used but that's not going to work as research was abandoned in 90s. Unfortunately I don't have any concrete data concerning half-life, protein binding etc. However, seeing it in its true colors I don't need them.

Well, it is possible to use semorphone as a substitute but it would call for ~4 injections a day in my experience.

I got back to buprenorphine s.l. immediately, I didn't even spend a whole day on it because my veins are already in bad shape.
 
To the OP:
I dunno... That N-methoxyethyl group looks a bit iffy to me.

The general rules for nitrogen substitutions are:
1. Methyl is the best substituent for agonist activity, and ethyl is just passable.
2. If the nitrogen substituent is a intermediate legnth, bulky alkyl group the compound becomes an antagonist. (Or at best a partial agonist.)
3. BUT addition of a phenethyl substituent results in a 14-fold increase in activity over morphine.

I guess the question here is, "Is the N-methoxyethyl group more like rule #2, or rule #3?"
My bet's on it being a weak partial agonist at best.:\
 
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Well duh, it's already known this is a partial agonist... it says so in the 1st post.
 
To the OP:
I dunno... That N-methoxyethyl group looks a bit iffy to me.

The general rules for nitrogen substitutions are:
1. Methyl is the best substituent for agonist activity, and ethyl is just passable.
2. If the nitrogen substituent is a intermediate legnth, bulky alkyl group the compound becomes an antagonist. (Or at best a partial agonist.)
3. BUT addition of a phenethyl substituent results in a 14-fold increase in activity over morphine.

I guess the question here is, "Is the N-methoxyethyl group more like rule #2, or rule #3?"
My bet's on it being a weak partial agonist at best.:\

I didn't assume semorphone was a partial agonist. I'd known it before. Simple googling 'semorphone' may give no results beside copies from wikipedia or wikipedia's copy from somewhere (doesn't matter...).

More information on this opioid can be found by its research name - Mr 2264. Synthesis is another story...

Those rules are general. Would an isopropyl substituent at 14. yield an agonist or an antagonist in hydromorphone? I don't know. It would probably no use both for junkies, and as a painkiller. But I do know that adding some nice alkyloxy group on 14. position or playing with position 7. in 7,8-didehydro- group of opioids made of 5 rings could change a lot. Why diprenorphine is such a strong antagonist by weight and buprenorphine is a partial agonist at mu receptors? They differ only on what is added on position 7. What I mean is morphine semi-synthetic derivatives' chemistry is more complex. Add pharmacokinetics and pharmacodynamics, and that's it.
 
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