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Monday, April 21, 2025

The Chemistry of Opioids

This post will be updated and expanded over time as I continue my research and gain more and more knowledge and experience in this field. This paper is by no means exhaustive and is to be seen as a lifelong work-in-progress.


Characteristics of an ideal opioid

  • High peroral/intranasal BA (bioavailability)
  • Potency anywhere between 1x - 18x in relation to Morphine.
  • Fast OOA (onset of action) and long DOA (duration of action) while having as short of an EHL (elimination half-life as opposed to analgesic half-life) as possible. Interestingly, Levorphanol provides these benefits. It is fast acting, making it ideal in cases where the medicinal effects need to show up quickly, has a long duration of up to half a day (yes, 12h) making frequent redosing unnecessary and thus economizes use, and finally the EHL of its metabolites is only marginally longer than its DOA (12 - 16h). This makes Levorphanol the ideal alternative to Methadone, as patients actually get a longer DOA while at the same time being able to taper off more quickly than with Methadone. Combine that with a lack of QR prolongation and doctors really have no excuses anymore to keep prescribing Methadone.
  • Peripheral antagonism with simultaneous cerebral agonism (possible avoidance of physical dependency and thus withdrawal syndrome? Need more data).
  • High psychoactive affinity (weak sedation - strong euphoria) for patients suffering from depression. Low psychoactive affinity for pain patients. 
  • No activation of κOR.
  • Absence of metabolic polymorphism as this would lead to a more or less strong, unpredictable dose variance among other possible effects.
  • Simple, relatively economical synthesis route.
  • High TI (therapeutic index).



Medicinal/Psychoactive Structure-Activity Relationship

  • Substituents on nitrogen have a very strong influence on the µOR activity of the opioid in question. The size of the substituent determines whether the opioid will tend more towards agonism or antagonism.
  • The analgetic potency of 4,5-epoxymorphinans is EXTREMELY sensitive to C14 substituents. Long arylalkyl chains on C14 create potencies several hundred to thousand times stronger than that of morphine, such as 14-Phenylpropoxymetopon or 14-Cinnamoyloxycodeinone for example.
  • Ketone groups that substitute hydroxyl groups lead to an increase in potency and analgesia, but have also been found to disproportionately increase the potential for respiratory depression.
  • Methyl and Ethyl groups increase µOR activity more so than Hydrogen, and aliphatic chains longer than Pentyl tend to decrease such activity, while Allyl, Cyclopropyl, Cyclobutyl and Cyclopentylmethyl groups cause a wholly antagonistic effect on the µOR.
  • 3-OH and 3-OAc potentiate opioids belonging to the Morphinan family, while other entry groups on 3-O tend to decrease or even completely negate any opioid effect.
  • Hydrazone on opioid molecules creates a so called "irreversible" µOR binding via a covalent bond on the receptor which effectively prevents the active opioid metabolite from detaching itself from the receptor. In practice the agonism is ofc not infinite, the DOA however lasts for an incredibly long time. Oxymorphazone is such an example (derivative of Oxymorphone). The disadvantage is obvious: strong increase in required dosage after only a short period of time due to the constant agonism of the opioid receptors. I fail to see the benefit of Hydrazone.
  • When it comes to Morphinans, an extension of N-Alkyl chains up to N-Propyl, tends to decrease µOR activity, while everything above it until N-Hexyl reverts the potency and in some cases even increases it. N-Phenylalkanes such as N-Phenylethane potentiate activity, but an extension of the alkyl chain could weaken that activity (I am not aware of such a case though. Let me know in the comments if that statement is true.).



A warning on superpotent opioids

It may be very tempting to produce and use opioids hundreds to thousands of times stronger than morphine, if only for the obvious economic benefits, since a couple grams could last you years. I can only warn against doing that though. Life is unpredictable and you never know what might happen tomorrow. If you're dependent and highly tolerant to something like PPOM and you end up in a freak accident on the road with 2nd/3rd degree burns all over your body, plastics having melted and hardened on your skin which the docs then need to saw off of your body, the medics can inject you only with that much hydromorphone or fentanyl until they run out. To make matters worse, you can't move, which means you cannot go and fetch your superpotent opioid batch while your biological clock ticks against you. This means that on top of all the accident-caused pain that you're feeling, you're additionally about to go through one hell of a withdrawal against which a fentanyl withdrawal will feel like a kindergarden ride. Especially if you've been taking a superpotent opioid that also happens to be long lasting. 
And hospitals won't have enough opioids to treat both you and all the other, "normal" patients. Also keep in mind that some countries have pretty harsh medical laws (medical rationing policies in hospitals, short supply of or total absence of very potent opioids such as fentanyl, etc.). 

And if for whatever reason it becomes an impossibility for you to keep synthesizing your superpotent opioids you can forget maintenance treatment. What doctor will allow you to...forget the doctor...what INSURANCE company will allow you to gulp down half a methadone bottle a day to feel well?

So think VERY CAREFULLY whether or not you want to enter such potency dimensions. They come with risk factors that are completely unique to themselves and utterly unpredictable. Also, remember back in the day when you switched from a low potency opioid to a more potent one and suddenly noticed how higher potency does not equal more euphoria? I remember when I switched from Tilidine to Heroin for the first time, the very first thing I noticed was how Tilidine, which is less potent by a factor of 20 - 25, actually gave me a stronger sense of euphoria than notorious Heroin.  That's a decision I immediately regretted. So instead of switching to ever more potent opioids, I recommend practicing opioid rotation with agonists that don't share cross-tolerance with each other. This is what is also clinically done to maintain the effects of opioids without increasing the dosage. It is both economical and fun. Stay safe...




Solvent ratios for various Opiates/Opioids

 Morphine ::: Methanol

1g/10mL


Thebaine ::: Ethanol

1g/10mL


Codeine ::: Ethanol

1g/???mL


Diacetylmorphine ::: TCM

1g/3mL


Diacetyldihydromorphine ::: TCM

1g/2.7mL


Hydromorphone ::: Ethanol

1g/1mL - 10mL


Oxycodone ::: TCM, Methanol

1g/???mL [Chl]

1g/???mL [Mth]


Oxymorphone ::: Boiling Acetone, TCM

1g/???mL [Ace]

1g/???mL [Chl]


Methadone ::: TCM, Ethanol

1g/3mL [Chl]

1g/8mL [Eth]


Levorphanol - TCM, any alcohol up to Isopropanol

1g/3.5mL [Chl]

1g/7mL [Mth]


Fentanyl : Methanol

1g/3mL - 10mL




International Nonproprietary Naming (INN) rules for Opioids


Nal-

Agonists/Antagonists that are related to Normorphine.


-orph- / -orphin

Agonists/Antagonists of the (4,5-epoxy)morphinan family.

Sugar derivative of morphine with no tolerance buildup

Here is a very fascinating goodie for my dear opiophiles. It looks very promising to the point that I may temporarily abandon my other projects and try out this opioid on myself to compare results. It would be the first "human" bioassay (because strictly speaking...I'm not human 🐉). In case you synth and try it out before I do: write down your results here in the comment section. Oh and definitely send me a small batch of it. It ain't illegal anywhere in the world, so don't worry about dropping the soap.

https://jumpshare.com/s/3PeaWeUukazyp2o5Ygga

Tilidine derivative

 Coming (not so) soon...german patent office better be quick 😒

Diacetyldihydromorphine aka Dihydroheroin, Paralaudin

 Coming soon...

Levorphanol aka Aromarone, Dromoran

This is actually a synthesis I did on August 2024, so more than half a year ago. Dextromethorphan was used as starting material for this synthesis, for various reasons: a) my first attempt at using Phenanthrene as a starting material was "successful" but gave very bad yields (7 - 14%). I assume this might explain the popularity of the Grewe Cyclization for opioid syntheses in general, because using the easy, comfortable Phenanthrene route where you already have the fundamental nucleus that all morphinans have and only need to hydrogenate the B and C-ring while adding/substituting the necessary functional groups, seems to deliver very bad yields unfortunately. This ties in directly to my second reason which is b) the much more economic route of DXM -> Levorphanol conversion and c) DXM is not a controlled substance here in Germany. Any person here can import as much of it as they want as long as it is used for non-commercial purposes.

I bought 80g of DXM HBr from a pharmaceutical company specializing in APIs based in India. I will start my first opioid entry with Levorphanol since it is the most simple member of the morphinan family. Just as Morphine is the simplest 4,5-epoxymorphinan, so too is Levorphanol which is the reason why I specifically chose this opioid because I can use it later as starting material for designing more sophisticated and potent derivatives, similar to how hydromorphone is a derivative of morphine (the 7,8-hydrogenated ketone of morphine to be pedantic). I believe the specially concentrated binding affinity (not to be confused with analgetic potency) (-)3-hydroxy-N-morphinan has on the µ-OR as opposed to 4,5-epoxymorphinans could be key in developing opioids with an above average euphoric response. This is my main motivation for opioid research. To develop agonists with almost no sedative, analgesic attributes while hitting all the right buttons to trigger the euphoric response. You only need two of such agonists with no cross-tolerance to each other (like morphine and methadone) and boom: you have a medical protocol consisting of bi-weekly opioid rotation to indefinitely treat depression without loss of the good effects that comes with chronic use of cross-tolerant opioids. Such euphoria-only opioids could be marketed as next-gen antidepressants. Still addictive as hell (in that case perhaps even more addictive) but at least they work in actually making depressive patients feel good and motivated and have enough energy instead of pumping them full with these worthless and toxic tricyclical ADs they're selling.

Now let's get to the actual meat and bones of this post.

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Levorphanol Tartrate Dihydrate Profile



Name: 

Levorphanol alias levo-3-hydroxy-N-methylmorphinan


Family: 

Morphinan


INN: 

Levorphanol, Aromarone, Dromoran


IUPAC name: 

(1R,9R,10R)-17-Methyl-17-azatetracyclo[7.5.3.01,10.02,7]heptadeca-2(7),3,5-trien-4-ol


Other names: 

(-)3-hydroxy-N-methylmorphinan 

(-)17-methylmorphinan-3-ol


Stereoisomers: 

Dextrorphan (+ isomer) 

Racemorphan (+/- isomer containing both the opioid agonist Levorphanol as well as the dissociative drug Dextrorphan)


Crystallography: 

Triclinic system


Salt forms tested incl. solubility ratio per unit water under normal conditions: 

L. tartrate dihydrate (10.8), L. hydrochloride (7.9), L. hydrobromide (3.7); These ratios explain why the otherwise rarely seen tartrate dihydrate is the salt of choice for Levorphanol manufacture.

!!!WARNING!!!

Levorphanol is an opioid with a high degree of metabolic polymorphism, so the following figures can vary more or less tremendously from person to person.

Bioavailability:

PO: 70%
INS: ~70%
INH: 100% (tastes and smells like how I imagine mildly burned rice must taste like. Surprisingly non-                       chemical aroma.)
SC: 100%
IV: 100%

Potency:

PO: 8:1 (where 1 is morphine)

INS: 8:1

INH: 6:1

SC: 3.5:1

IV: 5:1


Onset of action:

PO: 0.25h
INS: 0.05h
INH: 15 sec
SC: 0.08h
IV: 9 sec


Peak response:

PO: 2 - 2.30h
INS: 1h
INH: 0.40h
SC: 0.45h
IV: 0.30h


Duration of action:

PO: 10h
INS: 6h
INH: 3.80h
SC: 4.20h
IV: 3h


Sedative response (1-10):

5.5

Euphoric response (1-10):

7

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Synthesis and Chemistry

Reagents:

  • 3-methoxy-N-methylmorphinan hydrobromide
  • Distilled H2O
  • Any concentrated hydrohalic acid (50% HBr (aq) preferred, but 30% HCl (aq) is fine too)
  • Any lower alcohol up to isopropanol (Methanol should work best)
  • Any aprotic, non-polar solvent such as Trichloromethane
  • Any strong amine base (30% NH(aq) works best)
  • Tartaric acid
  • Activated carbon
  • Filter aid

The reaction mechanism itself couldn't be any simpler. The electrophilic methyl group of the aromatic ether is substituted with a good quality H+ entering group (provided by a hydrohalic acid) via a SEAR reaction, causing an electrophilic attack on the nucleophilic O- group and thereby replacing the methoxy group with an hydroxy group. This is achieved by mixing HBr (aq) (2.93 mol) with DXM HBr while heating it to reflux at 120°C for 150 minutes while stirring it with a magnetic stirring plate.



Conversion from DXM HBr...





...to Levorphanol HBr


This results in Levorphanol or (-)3-hydroxy-N-methylmorphinan hydrobromide as the main product with a methyl halogen as a byproduct (which is poorly soluble in water) and two other potentially hazardous byproducts, namely 10-ketolevorphanol and 2-chloro/bromolevorphanol. Halogenated pharmaceuticals are known to be neurotoxic and if HCl/HBr (aq) was used for the reaction, care must be taken to get the latter byproduct out of the opioid, preferrably down to ppm quantities, especially if injection is planned as chlorine atoms are small enough to bypass the BBB. The two byproducts were indeed detected and removed via a special recrystallization method (explained below). 

Byproduct #1: 2-bromolevorphanol HBr

Byproduct #2: 10-ketolevorphanol HBr

We will now move on to basify our Levorphanol HBr. After the above reaction is over, the mixture should be allowed to cool off to around 20°C and slowly added to a 2-phase mixture of NH3 (aq) (1.2 mol), distilled water (1.7 mol), methanol (0.69 mol) and chloroform (3.8 mol). Interestingly, methanol and chloroform shouldn't mix since the former is polar while the latter is a non-polar solvent, but that is just one more proof how theoretical chemistry often deviates strongly from practical reality.



After adding the NH3 (aq) to the TCM/Methanol mixture, two phases appear (the middle, milky white phase you see in the first photo only appeared temporarily after having poured the liquid ammonia into the system and then quickly disappeared for some reason. I have no idea what the hell that was and how that substance came to be): a top phase consisting of liquid ammonia and a bottom phase consisting of TCM/Methanol. Now stir the beaker for 15 minutes, put the mixture into a separating funnel and repeat the process for a total of 3x (obviously you throw away the aqueous phase, NOT the organic phase each time you're done).





Levorphanol freebase

Notice how the organic phase is not transparent anymore. That's the Levorphanol base having been dissolved, creating a saturated solution (comparable to a saturated saline solution).

Now what's the purpose of this? Why not just basify the Levorphanol salt by letting it react with NH3 (aq) and filter the insoluble base out of the liquid? The problem is that the bromide anion and the hydrogen cation in the HBr salt bond with NH3 to form ammonium bromide (NH4Br). That is itself a salt which immediately undergoes a dissociation reaction in the aqueous phase, giving a positively charged NH4+ cation and a negatively charged Br- anion. The hydrogen proton of the NH4+ will then, by way of an Areaction bond with the nucleophilic N of the Levorphanol base, making N electropositive as it donates an electron to the electrophilic proton. The hydrogen proton then bonds with the bromide anion and you end up with Levorphanol HBr again. All this happens too quickly for the Levorphanol base to dissolve in the organic layer. So trying to turn Levorphanol HBr into a base by letting it react with NH(aq) creates a never ending cycle of basification and neutralisation. To break this cycle we use an organic phase that employs solvents with the ability to dissolve the base only. The TCM/Methanol mixture does that. Unfortunately though, Branions are dissolvable in the organic phase too, which causes a certain portion of those anions to be present in the organic layer (16%). This means the bulk of the bromide gets extracted by NH(aq). Hence we make multiple extractions with fresh NH(aq), each time removing another 84% of the previous mass. The result is that the three extractions of the organic phase reduce the bromide impurity down to 0.41%. This is why I told you earlier to throw away the aqueous phase and not the organic one, because otherwise you'd be keeping the bromide anions while throwing away the delicious Levorphanol. Reminds me a little bit of some of those speedfreaks who follow the acetone wash guide on purifying their speed and accidentally end up throwing away the amphetamine while snorting the cut 😂

All right, now we have a Levorphanol base solution. Those who want to experiment with different salts can stop here and do the acid-base reaction with their acid of choice, while I'm going to turn the base into tartrate dihydrate. Anhydrous tartrate should be avoided as it tends to increase in hardness over time, thus making it difficult to chop and therefore sniff (kind of like acetone washed amphetamine sulfate that tends to take on this annoying shape of pellet-like powder where large quantities go right through your nose down into your throat as if you just snorted sand. 

Take a separate beaker now and pour into it distilled water (0.5 mol) with an equal amount of tartaric acid. Heat it to 45°C and mix it well until everything has been dissolved. Maintain the temperature between 45 and 50°C during the whole process. Make sure the beaker with the base solution is stirring while you SLOWLY pour in the aqueous acid (increase temperature to 78°C). Just dumping the acid into the base all at once will cause the neutralization reaction to happen so incredibly fast that the solution will almost instantly solidify which will look like this:


This will then require of you to re-dissolve the Levorphanol Tartrate by pouring in more water which is not only kind of a messy process but will actually cause, for some reason that is unknown to me, great difficulty for the Levorphanol Tartrate to form crystals later on during the recrystallization procedure. You know you've done it correctly when no solids form during the reaction (see photos below).




Tartaric acid (aq)

Levorphanol tartrate anhydrate

In general, it is always a good policy to pour in liquid chemicals as slowly as possible into reaction mixtures. Inorganic chemistry might reward quickness, organic chemistry however will punish you for it. Keep stirring the L. tartrate solution for 15 minutes. The neutralization reaction above is slightly exothermic and will increase the temperature of your solution by approximately 3°C for a couple minutes.

What follows now is the recrystallization procedure mentioned earlier to isolate the potentially toxic byproducts 2-bromolevorphanol and 10-ketolevorphanol and end up with a truly pharmaceutical-grade purity profile. This is really the most important part of this entire synthesis, especially if you plan on shooting it. We know what Levorphanol does. We do NOT know what those other mystery substances do. 

Now, after you've turned off the stirring magnet, slowly decrease the temperature down to room temperature over the course of a couple hours. The longer it takes for the temperature to fall, the bigger and more beautiful the crystal formations will be, regardless of the crystalline compound in question. That is almost a law of nature. Once the solution has reached room temperature, put the beaker into your refrigerator. Make sure to cause the least amount of movement to the solution as possible while walking to the refrigerator. Allow the beaker to remain in there until no more crystals form. This can take a couple of hours, an entire night or even days, depending on too many factors to count here. Once you no longer see more crystals forming, put the beaker into the freezer. Same principle of waiting applies here.



See the orange teint of the crystals? Those are the 2-bromo impurities.
Visible thanks to the bromine atoms that cause orange discoloration.
You don't have that luxury with oxygen atoms which is why you don't
see the 10-keto impurities even though they are still there!


What you see in the pictures above is L. tartrate anhydrate. Pulverize the crystals, put them in your oven on 60°C and wait for 4 - 6 hours. It really needs to be dirt dry because even a little bit of humidity will cause the product yield to suffer. The remaining solvent mixture in your beaker contains a large portion of the byproducts, which you can either throw away or you can distill the solvents out and use them for another project if you are a poor chemist (actually, it's more expensive to win back the solvents through distillation due to electricity costs, rather than simply buying a new bottle of TCM, Methanol, etc., but I suppose that depends on the quantity and where you live. Energy costs here in Germany have become a real nightmare.). 

Clean your beaker or take a new one and fill it with distilled water (2.4 mol), put activated carbon (0.024 mol) and filter aid (0.012 mol) into it, suspend the dry L. tartrate anhydrate powder into the mix, heat it to 84°C and stir it for 60 minutes. Vacuum filter the mixture into a flask and let it cool slowly as described above. What you'll get now are L. tartrate dihydrate crystals. Dry it again, prepare a 90% aqueous methanol solution (or any aqueous, lower alcohol above 80%), dissolve the dried L. tartrate dihydrate in it, heat it to 84°C again, stir for 60 minutes and let it cool off. You'll get the anhydrous salt again. These previous two recrystallizations essentially purified the Levorphanol from the two byproducts mentioned above. If you take opioids only perorally you can dry your L. tartrate anhydrate and call yourself the proud owner of 99.63% pure Levorphanol and proceed to get high as a kite. I however will recrystallize the salt back to its dihydrous form because I prefer to sniff and occasionally shoot. Repeat the process above only without the activated carbon and the filter aid and you'll get L. tartrate dihydrate. 

Note: I forgot to photograph the latter two recrystallizations. What essentially happened was the orange teint disappeared with every recrystallization until the crystals became as white as a snowflake. Note to self: don't do lab work while high. 


The L. tartrate dihydrate crystallized around my damn thermometer 😂😂😂



I just couldn't resist and had to press some of the crystals 😊
Imagine if I gave this to people telling them it was "fishscale cocaine". They'd
be dying left and right 💀
Btw, this is still somewhat wet because dihydrous L. tartrate is practically
impossible to press. It's just too fluffy to hold itself together like that.

And now it looks like crack. Imagine if I gave this to people telli...ah you know how it goes.


Completely dried. Look at those BEAUTIFUL crystals 😍😍😍


Now isn't that a nice yield? 91% of the product remained. In other words, 9% lost to
impurities and mass entropy. Couldn't be happier.



This is keeping me totally chilled indeed 😁😁😁


Levorphanol Tartrate Dihydrate

Wednesday, February 26, 2025

Introduction

I'm not going to post often here since it doesn't happen every day that I synthesize an opioid, much less a novel opioid that I designed myself, but when I do I'm going to post detailed information on the reaction mechanisms and the chemistry of both my own novel opioid(s) as well as novel synthesis routes of known opioids.

One last thing before I go into how to navigate this blog and what to expect: the target audience of this blog is primarily advanced organic chemists, hence why terminology won't be explained. Mere dabblers or non-chem junkies with an opportunistic desire to synth their own supply are at the WRONG place here! Those knowledgeable enough will get enough information to connect the dots and conduct the syntheses for themselves. This doesn't mean however that I won't explain things, even to novices if I get the impression that they are very serious and honest about learning.

The posts in this blog are subdivided in labels of "Compounds", "Novel Compounds", "Novel Routes", "Salts", "PDF" (patent files or interesting research papers) and finally "Test Reports" which you can filter by scrolling to the bottom of any blog post and clicking on the aforementioned categories. All syntheses of both known as well as novel opioids will be posted in the first two sections respectively. Please note that "Novel Compounds" does NOT refer to new opioids on the market, but to my own inventions. Same is true for "Novel Routes". This includes improved syntheses of existing routes. Novel agonists that I have developed myself have to be tested first regarding their toxicity and analgetic potency on wistar rats (particularly valuable due to their high level of genetic homogeneity, ease of handling, and reproducible results). These posts can be found in the "Test Reports" category. The "Salts" label will contain my experiments in solubility enhancement with chemical, physicochemical, and biological considerations. I will be converting base opioids into various salts, from relatively known ones such as hydrochloride and tartrate to the more exotic ones that have never been tried such as punicate (from punicic acid, which is contained in the lovely pomegranate) or cinnamate (mmmh, cinnamic acid). The goal is to find a salt that will make the compound hypersoluble in water while hopefully also increasing the onset and duration of action. To give an example, it was observed that single salt amphetamine in dextroamphetamine preparations was not a good choice for fast and sustainable psychostimulant effects. Instead, Adderall XR® was designed as a combination of the aspartate and sulfate salts of amphetamine, plus the saccharate and sulfate salts of dextroamphetamine. These different salts in a single drug product allowed different metabolism rates and possessed different onsets of action. This resulted in a faster induction of therapeutic effects while maintaining those effects for a sufficiently long time (see https://pubmed.ncbi.nlm.nih.gov/28763533/). Many chemists often underestimate how the physicochemical and biological properties of APIs are greatly affected by their salt forms. The choice of a particular salt formulation is based on numerous factors such as API chemistry, intended dosage form, pharmacokinetics, and pharmacodynamics. This means the appropriate salt can improve the overall therapeutic and pharmaceutical effects of a compound, or have a detrimental effect if a bad salt formulation is chosen as shown by the example above.

The opioids that I am interested in and therefore will be posting about, belong to the following families: 4,5-epoxymorphinans, morphinans, 4-phenylpiperidines and related azacycloalkanes (with special respect to a Tilidine derivative of my own that I will be experimenting on myself in the future after having gone through my rat testing protocol), 3,3-diphenylpropylamines, atypical opioids, and lastly I will be experimenting with the N,N-diallyl- and N-methyl-N-allyl quaternary salts of (4,5-epoxy)morphinans since there is some information suggesting how these functional groups make the opioid antagonistic only towards the peripheral effects while leaving the CNS activity untouched (therefore eliminating or at least vastly reducing the possibility of lethal ODs and other non-lethal but obnoxious side effects associated with opioid use such as constipation).

I will be staying faaar away from benzomorphans since most of them don't have any significant MOR agonism (and those that do have it are usually disgusting dualists that feel as crappy as buprenorphine does) and induce more often than not psychotic freakshows which I am not interested in (they are most certainly fascinating from a Quant/Qual SAR perspective, but I will be only documenting those opioids here that belong to the above mentioned families that I am recreationally interested in).

I think that's about it for now. I hope you enjoy your stay here...

The Chemistry of Opioids

This post will be updated and expanded over time as I continue my research and gain more and more knowledge and experience in this field. Th...