Editing Talk:2552: The Last Molecule

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Unsuccessfully tried to search for a match to the image of the chemical compound. Did find this, which is difficult to use on a cellphone: OSRA: Optical Structure Recognition:  https://cactus.nci.nih.gov/cgi-bin/osra/index.cgi [[Special:Contributions/172.70.211.172|1 not72.70.211.172]] 07:43, 9 December 2021 (UTC)
 
Unsuccessfully tried to search for a match to the image of the chemical compound. Did find this, which is difficult to use on a cellphone: OSRA: Optical Structure Recognition:  https://cactus.nci.nih.gov/cgi-bin/osra/index.cgi [[Special:Contributions/172.70.211.172|1 not72.70.211.172]] 07:43, 9 December 2021 (UTC)
 
:I've tried to search for SMILES of the molecule, but also got nothing: https://pubchem.ncbi.nlm.nih.gov/#query=C1(C2CC(CCC)C(CC)C2(CCCC))C%3DCC(C(%3DCCC(%3DC)CC)C(C)C)%3DC1 [[Special:Contributions/162.158.222.137|162.158.222.137]]
 
:I've tried to search for SMILES of the molecule, but also got nothing: https://pubchem.ncbi.nlm.nih.gov/#query=C1(C2CC(CCC)C(CC)C2(CCCC))C%3DCC(C(%3DCCC(%3DC)CC)C(C)C)%3DC1 [[Special:Contributions/162.158.222.137|162.158.222.137]]
::Let's name it Excacidin ;) [[User:256.256.256.256|256.256.256.256]] ([[User talk:256.256.256.256|talk]]) 07:19, 10 December 2021 (UTC)
+
::Let's name it Excacidin ;) [[User:256 256.256.256|256.256.256.256]] ([[User talk:256 256.256.256|talk]]) 07:19, 10 December 2021 (UTC)
:: Here is updated SMILES taking into account comments below: N1(C2OC(CO)C(O)C2(OCCC))C=NC(C(=NCC(=O)O)N)=N1 [[Special:Contributions/162.158.222.123|162.158.222.123]] 16:44, 14 December 2021 (UTC)
 
  
 
I truly don't understand the God part of the current explanation. [[Special:Contributions/172.68.110.121|172.68.110.121]] 07:55, 9 December 2021 (UTC)
 
I truly don't understand the God part of the current explanation. [[Special:Contributions/172.68.110.121|172.68.110.121]] 07:55, 9 December 2021 (UTC)
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:For obvious reasons, as long as you limit the number of atoms involved the number of possible "molecules" is - in a mathematical sense - finite. (As there is only a finite number of reasonable stable elements.) But already simple things like polymers can bind millions of atoms in a single molecule. Together with the possible variations intrinsic to such polymers a simple "material" like phenolic resin [[https://en.wikipedia.org/wiki/Phenol_formaldehyde_resin]] is a mixture of more different chemical compounds (in a strict sense) than mankind can ever describe. For all practical application this compexity is not relevant, so no one really cares about.
 
:For obvious reasons, as long as you limit the number of atoms involved the number of possible "molecules" is - in a mathematical sense - finite. (As there is only a finite number of reasonable stable elements.) But already simple things like polymers can bind millions of atoms in a single molecule. Together with the possible variations intrinsic to such polymers a simple "material" like phenolic resin [[https://en.wikipedia.org/wiki/Phenol_formaldehyde_resin]] is a mixture of more different chemical compounds (in a strict sense) than mankind can ever describe. For all practical application this compexity is not relevant, so no one really cares about.
 
Additionally there is no clear boundary between typical molecules and other types of condensed matter, like crystals. Same applies to biochemistry. Does chemistry include bio-molecules? If yes, the chemistry guy have to include all the gene sequencing in their to-do list.
 
Additionally there is no clear boundary between typical molecules and other types of condensed matter, like crystals. Same applies to biochemistry. Does chemistry include bio-molecules? If yes, the chemistry guy have to include all the gene sequencing in their to-do list.
::What is this practical applications?  This is XKCD!  I am curious about what are the limits on molecular size (if there are any).  You often learn things by looking at the boundaries or extremes, even if those boundaries are (or appear) unatainable in practice. I wish What If was still going, seems like an interesting question for Randal. [[Special:Contributions/108.162.245.13|108.162.245.13]] 19:42, 19 December 2021 (UTC)
 
  
 
"how fast does light travel in one direction?" is not a good example for incompleteness in physics, because this question was settled by Michelson and Morley in the 19th century (answer: it travels with the speed of light)
 
"how fast does light travel in one direction?" is not a good example for incompleteness in physics, because this question was settled by Michelson and Morley in the 19th century (answer: it travels with the speed of light)
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:My physics professor from freshman year: "If you're ever in a room with physicists who say that the physics of Earth are done, and there's nothing else left to calculate, ask them "what about turbulence?". You'll be sure to get some dirty looks."[[Special:Contributions/108.162.246.122|108.162.246.122]] 21:08, 9 December 2021 (UTC)
 
:My physics professor from freshman year: "If you're ever in a room with physicists who say that the physics of Earth are done, and there's nothing else left to calculate, ask them "what about turbulence?". You'll be sure to get some dirty looks."[[Special:Contributions/108.162.246.122|108.162.246.122]] 21:08, 9 December 2021 (UTC)
 
--[[User:Marceluda|Marceluda]] ([[User talk:Marceluda|talk]]) 15:32, 9 December 2021 (UTC)
 
--[[User:Marceluda|Marceluda]] ([[User talk:Marceluda|talk]]) 15:32, 9 December 2021 (UTC)
 
 
I'd argue that fusion on earth is an engineering problem, not a matter of physics completeness (yeah, engineering is just applied physics and math just theoretical physics and biology what happens when you close two physicists in a room for too long, but still). Also, the problem of the symmetry of light speed is, from the present understanding of physics, a matter of metaphysics. [[Special:Contributions/172.68.94.143|172.68.94.143]] 13:42, 10 December 2021 (UTC)
 
:Having worked in fusion research, I'd say it's still a physics problem because we don't yet know if it's physically possible for a burning plasma to be confined for long enough on a small enough scale to create a viable power plant. It's not necessarily just a question of designing the right machine, if you see what I mean. And if it was, I'd like to think we'd find a few hundred billion of dollars of funding and just get it done. IMO the reason it's not a funding priority is that we can't be sure it would work with _any_ amount of money. That said, while it's potentially a question of great value to humanity, I don't think it's significant in terms of the completeness of physics as a field. --[[User:192·168·0·1|192·168·0·1]] ([[User talk:192·168·0·1|talk]]) 15:18, 10 December 2021 (UTC)
 
:To rant further about fusion funding, we don't know whether we can win any given war either but that doesn't stop us spending trillions of dollars on them. Maybe if we called fusion research "the war on paying for electricity / wrecking the environment" maybe we'd get it sorted. --[[User:192·168·0·1|192·168·0·1]] ([[User talk:192·168·0·1|talk]]) 15:23, 10 December 2021 (UTC)
 
 
Regarding the final molecule, using the above mentioned cactus website optical recognition I got: *[C@H](*CC[C@H](C)[C@H](C1CC1C[C@H](CC)CCC)C2[C@H](*)[C@@H]2C)CC3C*(CCC)C(CCC)[C@H]3CCCCC, which isn't recognized as a molecule. Anyone have any better ideas on if there is a similar known molecule? [[User:Stickfigurefan|Stickfigurefan]] ([[User talk:Stickfigurefan|talk]]) 17:16, 10 December 2021 (UTC)
 
 
Regarding the completeness of chemistry, I see no reason why a DNA molecule can't be longer than observable universe (it definitely wouldn't collapse into black hole ; obviously, tugging on it would break it somewhere). Regarding the completeness of biology, what organism would such molecule encode? While, mathematically speaking, observable universe is finite, I would consider this idea alone to ensure chemistry and biology can't ever be complete. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 23:35, 10 December 2021 (UTC)
 
 
Should we really use "citation needed" for a quotation, where we might actually want a citation? We're only supposed to use that ironically here. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 17:46, 10 December 2021 (UTC)
 
 
== Why citation needed? ==
 
 
I saw a citation needed about the Higgs Boson. Is it needed for humor? The higgs boson isn't obvious.--[[Special:Contributions/172.70.34.191|172.70.34.191]] 19:14, 10 December 2021 (UTC)
 
 
== Circular reasoning ==
 
 
I think something could be added about how determining how "complete" is a discipline already requires a complete knowledge of that discipline, even if we limit this to the inappropriate "number of known entities" approach. Some plausible estimates are naturally possible and a historic example seems to be more in line with the current explanation. A good fit seems to be how in physics the proton, neutron and electron model seemed at some point quite complete and was less crowded than the current one, still not sure how much of this understanding is a myth or how to put it in the explanation, so I prefer to leave it to someone else. For biology Wikipedia has {{w|Biological dark matter}} and the more theoretical {{w|Shadow biosphere}}, in case the number of unstudied multicellular organisms isn't sobering enough. [[Special:Contributions/172.70.98.153|172.70.98.153]] 02:07, 12 December 2021 (UTC)
 
 
== Serious hypothesis for the molecule's structure ==
 
 
I'm not sure why everyone keeps interpreting the picture as only containing carbon atoms. The leftmost moiety is clearly an ''O''<sup>2</sup>-substituted furanosyl group; exactly which furanose it is is uncertain, since the stereochemistry is not indicated at all. It could be <small>D</small>-ribofuranose, <small>D</small>-arabinofuranose, <small>D</small>-xylofuranose, <small>D</small>-lyxofuranose, or any of their <small>L</small>-enantiomers.
 
 
The central ring best matches the pattern of a 1,2,4-triazole, just looking at the bond patterns. It is consistent with how I've seen them in other compounds. Similarly, the rightmost group is clearly the -COOH of a carboxylic acid.
 
 
Probably the most ambiguous group is the one second from the right. Based on the bond patterns alone, it would be consistent with an amidine, which is probably the possibility most likely to occur in real compounds. However, ''N''′-monosubstituted amidines seem pretty rare based on a cursory search, and most likely tautomerize quickly into ''N''-monosubstituted amidines. I don't have any other idea of what it could be, though.
 
 
I strongly suspect that the furanose is <small>D</small>-ribofuranose. The leftmost three groups can be seen as a modification of [[wikipedia:Adenosine|adenosine]], which is one of the nucleosides found in DNA. In addition, '''the majority of this molecule exactly matches the antiviral drug [[wikipedia:Taribavirin|taribavirin]]''', which is used against hepatitis C and influenza. In fact, the drug may very well have been the inspiration for this molecule. The only two differences are an ''O''<sup>2</sup>-propyl substitution on the ribofuranose, and an ''N''′-(carboxymethyl) substitution on the amidine.
 
 
Assuming this interpretation of the molecule's structure is correct, its preferred IUPAC name (PIN) is "[(amino{1-[(2''R'',3''S'',4''R'',6''R'')-4-hydroxy-5-(hydroxymethyl)-3-propoxyoxolan-2-yl]-1''H''-1,2,4-triazol-3-yl}methylidene)amino]acetic acid". [[User:LegionMammal978|LegionMammal978]] ([[User talk:LegionMammal978|talk]]) 05:29, 12 December 2021 (UTC)
 
 
== E. O. Wilson found a lot of ants ==
 
 
Coincidentally, world-renowned myrmecologist [https://en.wikipedia.org/wiki/E._O._Wilson E. O. Wilson] — who personally discovered more than 400 species of ants — died on 2021-12-26. Reading the comic in January 2022, I initially took "they keep finding more ants" as a posthumous homage to Wilson... but as this comic was apparently published 2021-12-09, I guess that would have required a time machine on Munroe's part. Just a coincidence, then. [[Special:Contributions/172.70.230.153|172.70.230.153]] 16:10, 3 January 2022 (UTC)
 

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