How can scientist tell if a compound will work as a drug?

[TheBlackPope]

I was wondering how a scientist or a pharmacist can look at a chemical structure of a compound and determine how that will work on the human body.

Am I wrong about this completley, and they just test random compounds out on people and some turn up being dope when others don't?

Also, I know that dope that works on certain receptors get you high. Am I to understand that all dope that works on those receptors would get a person high?

[trptamene]

You can make assumptions as to the activity of a compound by its structure based on comparison to similar compounds with known activities. Usually there is a defining feature that makes it w/e type of drug....a phen a tryp an opiate or w/e.

They test compounds on animals like rat first to check for toxicity and potency before trials in human. In the more classical approach one synthesizes a suite of compounds w/ different strucutural variations and then assays them for their activity...sometimes this might be scores of derivatives and the term "random" could be somewhat used appropriately. More modernly the compounds and receptors can be modeled on the computer and the structure and electronics of it be optimized to being highly specific for that receptor and highly potent as well.

[TheBlackPope]

Oh. So if there was a random object no one had ever consumed, or had ever consumed in large amounts, we would not be able to tell if it has recreational/drug abilities?

I'm wondering how something like N2O was determined to be a drug. C2O H2O that shit doesn't work as a drug, yet N2O does?

[JDreaming]

Read about Structure-Activity Relationships (SARs) in any pharmacological data website you can find. It is possible to judge the likely effects of a compound based on the known effects of another related compound, and the molecular differences between the two. Short of conducting testing in living subjects the study of SARs is one of the best available tools.

You would be correct to think a substance that acts on receptors known for generating psychoactive effects would cause a psychoactive state. Substances that inhibit reuptake of dopamine would probably have pharmacological similarities with cocaine, those that agonize the 5HT2A receptor would resemble a psychedelic, those that bind to the CB1 receptor would have similarities to THC, etc. There are a great many different receptors that are behind the effect psychoactives have upon our brains and our bodies.

[radiometer]

I'm wondering how something like N2O was determined to be a drug.

Nitrous oxide was discovered by Joseph Priestly in 1772. Mr. Priestly also discovered oxygen, nitrogen, and ammonia. He discovered the activity of nitrous oxide through experimentation. Things are done very differently these days, centuries later.

http://en.wikipedia.org/wiki/Structu...y_relationship

That'll give you a start.

[TheBlackPope]

Wait, he just huffed that gas and got fucked up?

Christ. I thought I was the most stupid person in the world, guess not.

Ok, thanks alot, but this really makes me wonder: There must be thousands of compounds out there that can act as either a drug w/ medical benefit or a drug w/ recreational benefits!

And then imadgine all the rest that could be synthesized...all the analouges... Jesus that sounds fucking huge!

What is to say something like my carpet can't get me high in a certain amount? Is there at least one defining thing, like a chemical group at least, that all/most dope must have to work?

[vantranist]

Based on what the other posted have already pointed out, there is a good chance he new what the n02 was going to do to him based on his other findings... i doubt he was just huffing random compounds he was creating.

I am sure he started on some other similar molecule and mabye on animals too... however i didnt read the link, mabye he is that stupid.

[psyche]

Without better knowledge I wouldn't be surprised at all if it'd been an accident. Many drugs have been discovered that way, and remember the year was 1772. It was the age of reason, yes, but science science really took big steps in the 19th century.

Later it was used to amuse people in the shows on the marketplaces. They would pick participants in the crowd and give them some n20, and that was basically the show; other people watching other people stumbling on a stage high on n20, but they wouldn't care if they had a hit or two. Another man whose name I forgot used it during the removal of teeth and so they discovered more useful purpose for this gas.
Btw I wonder if the timing of the discovery has anything to do with the legal status of n20 and ether nowadays; everything from the 19th century and forward seems to be strictly controlled: morphine (1906), cocaine(1859), heroine(late 18th century), amphetamine(late 18th century, though discovered later to be active).

Well, that's a bit offtopic, so I better stop. Interesting thread and a subject that I've been interested in but don't know a lot about.

Is there at least one defining thing, like a chemical group at least, that all/most dope must have to work?

As JDreaming already pointed out, substances that are psychoactive usually chemicaly resemble our brains own neurotransmitters. Psychedelic drugs have indole-structure like serotonin, amphetamines have phenyl-ring to begin with, and act more on dopaminergic systems.