Monday, November 21, 2011

Monday's Molecule #150

Today's molecule has a common name but this time I'll need the complete IUPAC name. There is considerable controversy over whether this molecule actually exists in most cells.

Post your answer in the comments. I'll hold off releasing any comments for 24 hours. The first one with the correct answer wins. I will only post correct answers to avoid embarrassment.

There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your comment.) Every undergraduate who posts a correct answer will have their names entered in a Christmas draw. The winner gets a free autographed copy of my book! (One entry per week. If you post a correct answer every week you will have ten chances to win.)

Some past winners are from distant lands so their chances of taking up my offer of a free lunch are slim. (That's why I can afford to do this!)

In order to win you must post your correct name. Anonymous and pseudoanonymous commenters can't win the free lunch.

UPDATE: This one was more difficult than I expected. The molecule is oxalosuccinate or 1-oxopropane-1,2,3-tricarboxylate. I posted all the answers that used this IUPAC name or 1-oxopropane-1,2,3-tricarboxylic acid. This is clearly not the acid form of the molecule but that didn't make you ineligible to win the prize.

Oxalosuccinate is thought to be a transient intermediate in the reaction catalyzed by isocitrate dehydrogenase (citric acid cycle) but this is only a hypothesis—the intermediate has never been detected.

The molecule contains a chiral carbon atom (C3 of oxalosuccinate and C2 of oxopropane). I was expecting all answers to specifically identify the [2S] or [3S] stereoisomer, especially since we had recently discussed stereoisomers on this blog. "Cyau" was the only one to get this correct (on her second try) but she is not eligible because she didn't identify herself.

RaulFelix was the first person to name the molecule as 1-oxopropane-1,2,3-tricarboxylate and she would be the winner if I knew her real name. That means Vipulan Vigneswaran is this week's winner, beating out Joseph Somody by less that one minute.

Nov. 2009: Jason Oakley, Alex Ling
Oct. 17: Bill Chaney, Roger Fan
Oct. 24: DK
Oct. 31: Joseph C. Somody
Nov. 7: Jason Oakley
Nov. 15: Thomas Ferraro, Vipulan Vigneswaran


  1. Oxalosuccinate
    1-Oxopropane-1,2,3-tricarboxylic acid, or
    1-Oxopropane-1,2,3-tricarboxylate ion

  2. Would this be (S)-1-oxopropane-1,2,3-tricarboxylic acid?

    I'm honestly not sure as to the biological relevance as of yet.

  3. 1-oxopropane-1,2,3-tricarboxylate

    or Oxalosuccinate

  4. 1-Oxopropane-1,2,3-tricarboxylic acid

  5. Oxalosuccinic acid.

    I am hoping that Wikipedia is correct in listing its IUPAC name as "1-Oxopropane-1,2,3-tricarboxylic acid".

  6. Argh... It turns out I can't tell left from right:

    I believe the molecule is (2S)-1-oxopropane-1,2,3-tricarboxylic acid.

  7. RaulFelix (, November 23, 2011 10:38:00 AM

    RaulFelix is Raul A. Félix de Sousa (me), but don't worry, I live in a distant land (Brazil) and therefore, I wouldn't be elegible for a lunch anyway.

  8. RaulFelix says,

    RaulFelix is Raul A. Félix de Sousa (me), but don't worry, I live in a distant land (Brazil) and therefore, I wouldn't be elegible for a lunch anyway.

    Damn. I wish you'd told me earlier so I could have declared you the winner. Now I have to treat Vipulan to a lunch 'cause he's right here in Toronto. :-)

  9. Next monday I'll try to be just as fast, just to make you save.