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  • I said they were gonna a little bit about this molecule here.

  • This crazy, complex looking piece of molecular architecture, which is called strengthening, which, no doubt you probably will have heard Officer, a well known poison these days.

  • It's used for killing wraps, but in the past it was a medicinal compound, especially in the Victorian area, So that point in time it was used for all sorts of ailments, like headaches.

  • It was one of the very first athletic performance enhancers.

  • Believe it enough.

  • And, of course, it's a poisonous, really no useful in any of these respects whatsoever.

  • It comes from the seeds of a tree in the Philippines on dhe.

  • Over hundreds of years, the Filipinos had used the extract of this bean as they called the seed, to treat various elements, so it was sort of herbal type of medicine.

  • It works on the nervous system, so I'll give you a bit of a tingle, obviously, in high doses or actually not that high doses very severe effects on you.

  • But if it's something, you take something in tracks, everybody get bit of a tingle, and perhaps you feel it like it's doing good rather than harm.

  • So in small quantities it was used for centuries.

  • But actually, it's it's got no real beneficial effect, a za medicine and indeed, you know, famously it's being used in all sorts of murder mystery cases.

  • I have just one story about strengthening, but I really like it.

  • Just before I started as a PhD student, a Brazilian professor visiting the chemistry department took some strengthening out to the store because he wanted to poison his wife.

  • But being a professor, he was a bit absent minded, and he mislaid the straightening.

  • He lost it on Dhe.

  • He got really worried that somebody might get poisoned other than his wife.

  • So he went to the police and admitted everything.

  • And then the strict mean was found in his jacket pocket, hanging in his wardrobe, so his wife was safe.

  • What happened to the professor?

  • I have no idea.

  • One of the founders of Stanford University was poisoned by strictly murdered by straightening, and her last words were that this is the most horrible and painful death and fiction.

  • It's been used a lot.

  • I get Christie 34 novels of hers had strict coming in in the Grand Budapest hotel it's in.

  • There is a is a poison.

  • Actually, there hasn't been money.

  • Deaths are murders through the use of strict mean luckily, So this is given to us by signaled rich for the use in the periodic videos.

  • So thank you very much to them.

  • It is about a gram in here, and it takes about 10 to 50 milligrams.

  • T kill a human being.

  • This tree gives beautiful white flowers very fragrant smelling, but presuming it's in there to stop animals from eating seeds, you know the animal takes ah, bite of it and doesn't finish its meal.

  • Like many of the campaigns I talk about, it works on the nervous system means that you or your muscles got control and you know you die of asphyxiation of not being out of breath because the lungs aren't working properly.

  • Imagine it is Ah Siri's of electrical cables with junction boxes in between and the ends.

  • He got sensors on DDE muscles at the other end, so sensors build up using irons, a concentration of a positive charge, using generally sodium potassium calcium mines that then fires intellectual charge down the the cable to the other end and then counsel mines, allowing the release of neurotransmitters to go and tell the muscle or brain or whatever is on the other end.

  • What to do So this interferes of that process at the junction boxes eso.

  • This inhibits both sodium and chlorine in channels, which is unusual.

  • Normally, a molecule will interact with just one type of receptor.

  • Is this it's interactive.

  • Two types of receptor get there.

  • Yeah, that's a good question.

  • So if you ingest something, it'll go obviously into your gut.

  • Once it's in the gut, it can then pass through the gut to blood Barry, at least be charged to do that.

  • So I got basic aiming on here.

  • It then gets into your bloodstream in the bloodstream, then transports it around your body.

  • This, obviously with the blood, will go to all your muscles on dhe.

  • Start to interfere with any of your muscular junctions that it comes across.

  • It's not a very good murder weapon, because it was stay in the body for years, traces off it, so I'd be very easily identifiable.

  • Mmm.

  • Nice of you.

  • Just strictly taste like they say it tastes bitter and on strengthening.

  • This is tertiary a mean here this this blue on anything with tertiary aiming always taste incredibly bitter.

  • Love insects have thes Toshi alien molecules on back so that they taste horrible.

  • So a bit like licking a brass or copper spoon.

  • We are really bitter in really not very pleasant.

  • But also again, not not the best poison Because you get a taste in your capital.

  • Hey, all right.

  • From the bank, the high security containment system, and just take a little luck.

  • It what strictly looks like.

  • So we have to chop.

  • It's no longer here shows maybe, maybe 100 milligrams.

  • No, no grandma tour.

  • Let's just take that.

  • Oh, my God.

  • So that we get just, uh a white hired essentially looks fairly innocuous.

  • When the majority of chemicals that you were with not toxic maybe it was so cold, harmful, maybe slightly crazy for majority.

  • Not that way.

  • So I wouldn't my pitch to students toe of anything.

  • It's extremely toxic, although we have made of few natural products over the years, which which really quite patient.

  • But this is quite dangerous substance and not something that the likes of which would normally be working with I look at that.

  • And I think, Wow, that's beautiful.

  • Such a really unique architectural of these ring systems.

  • You've got Hodgins pointing in tow.

  • This cavity here, seven members rings, five of murdering six members rings all sorts of different molecular architectural pieces in there.

  • And for the synthetic chemist, that makes this an absolutely outstanding challenge.

  • This is the Everest, if you like, of the total synthesis type of world, so is isolated.

  • But the French chemists in 18 18 So nearly 200 years ago on it was about 120 years later, by the time chemists had figured finally figured out what unearth structure Waas because it's just so complex.

  • So there are over 102 150 papers attempting to find out what the structure of strict Ning Waas and eventually, in 1947 two chemists Robert Robinson, who's later became Sir Robert Robinson at Oxford University.

  • He proposed the correct structure on dhe looks.

  • Onda, completely separate.

  • Chemist, also did but brought.

  • Robinson was very famous in his day, and this is a culmination of two decades worth of work in his laboratories.

  • Seven years later, Robert Burns Wood Wood was the first group to synthesize it, Robinson had said for its molecular slides, it's the most complex molecule ever known, since Woodward's original census has Bean 17.

  • Further since he's so 1950 four's the first census has around 28 synthetic steps.

  • Different things that you have to do.

  • And the yield was minuscule.

  • It was they're starting from tens of kilos in getting milligrams out.

  • 0006% yield, which is a very small amount on dhe.

  • Quite a lot steps.

  • 28 steps, actually is for the complexity of this molecule is still quite competitive.

  • The next census was carried out in 1992 so many years later by Philip Magnus.

  • That was again 28 steps.

  • But he got up 2.3% yield considerably more efficient, about 1000 times more efficient but still very low yield.

  • In each case, all of these people were developing a new type of bombs connection connecting reaction, and they're putting that into operation.

  • So Magnus, in in his census, is making this bond in this bond in the key step.

  • Using a deal was older top of reaction.

  • Woodward had used, obviously, that the synthetic chemistry of the day and in 40 years have passed by the time Magnus came to doing it in 1994 was the next insists on that one and went up to 3% yield using Larry over Mons chemistry.

  • These RL, you know, incredibly eases the rock stars of the organic chemistry world that are coming to play here.

  • Eso at time moves on 2007 pounder.

  • I got it down to 16 steps, 2% yield.

  • By 2011.

  • We have the shortest census ever.

  • Nine Steps by Chris Van Duyvil.

  • Terrible yield.

  • There was one really difficult step in there, but nine steps when you think the original was 28 eyes quite incredible and probably the best since your sat.

  • There is by David McMillan 12 steps, but 6% yield so considerably stronger and 1000 times more efficient in the original synthesis.

  • And this is the progress that organic chemistry is made only in structurally sedation.

  • So 20 years worth of work in the 19 thirties and forties, 250 papers to determine the structure of this today, one of my PhD students will be able to determine the structure in an afternoon because spectroscopic techniques have come an incredibly long way.

  • There were almost none back in 1946 had infrared.

  • There was an X ray of this in 1952.

  • So that was the very first X rays.

  • But in 1946 that didn't exist.

  • So back then they had to literally chemically react it and figure out what bombs would have been broken through that type of reaction.

  • So there's a real detective story back when using evidence chemical evidence to determine structure was now we cannae spectroscopy.

  • Well, I'll put some of that back in the bottle on the rest will have destroyed.

  • And then it was sitting a lot covered.

  • Yeah, just in case you get some rats in the the lab, do you think?

  • But every few seconds of brains saying Breathe in, breathe out, breathe in, breathe out.

  • It does it automatically or moving muscles.

  • So if you stop any of those signals, then obviously muscles stop.

  • And if you stop breathing, you're gonna die pretty quick.

I said they were gonna a little bit about this molecule here.

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致命的馬錢子 - 視頻週期表 (Deadly Strychnine - Periodic Table of Videos)

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    林宜悉 發佈於 2021 年 01 月 14 日
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