Sciencemadness Discussion Board

Preparation of Cialis (tadalafil)

madcedar - 1-7-2012 at 20:27

Just after it's release in France it was known as "le weekend" (artistic licence used) because the half life of cialis was long enough for it to be effective for the entire weekend compared to the relatively short half life of viagra.

I was checking out how to make it and I was shocked to see that it uses two recreational drug precursors, piperonal and nitroethane, along with a potential recreational drug precursor, tryptophan (yeah it's a stretch saying it's a precursor). No wonder it gives you an erection.

Please find attached in this post and the next one (had to split it over two posts because of the size of the pdf) a great survey on cialis.


Attachment: tadalafil.part1.rar (1.4MB)
This file has been downloaded 846 times

[Edited on 2-7-2012 by madcedar]

madcedar - 1-7-2012 at 20:28

Here is the second half of the pdf from the fist post. You need to download both rar files in order to extract the pdf.

Attachment: tadalafil.part2.rar (1.3MB)
This file has been downloaded 796 times

DoctorOfPhilosophy - 2-7-2012 at 15:55

7-Zip isn't opening your RAR files, but from what I know, pharmaceuticals / drugs generally have similar precursors. I believe this is because they have to fit snugly into your brain receptors (that's an unscientific way of putting it.) If you look at the tadalafil molecule structure, you will even see the piperonal and tryptophan moieties attached to the molecules. My guess is they stick to the neurons. Be careful with making it though - you probably don't want to be ordering those precursors!

[Edited on 2-7-2012 by DoctorOfPhilosophy]

smaerd - 3-7-2012 at 08:04

I really like the way they built the final heterocycle, pretty elegant.

mr.crow - 3-7-2012 at 09:39

Quote: Originally posted by smaerd  
I really like the way they built the final heterocycle, pretty elegant.

Me too. Its such a beautiful synthesis and really simple.

Here is another PDF

Also compare it to Sildenafil, which looks like someone stuck a bunch of shit together.

Hehe boner pills

kavu - 3-7-2012 at 09:52

This condensation is a useful way to make diketopiperazines, works pretty well even in large scale. Further reduction with LAH gets rid of the carbonyls and voilĂ , you have a waterproof way to piperazines. Even stereospesifically, given that you started with an enantiopure amino acid. Really useful piece of welding together such heterocyclic functionalities.

[Edited on 3-7-2012 by kavu]