Monday, August 27, 2012

Monday's Molecule #183

Last week's molecule was a small protein machine that pumps protons across a membrane (ubiquinol:cytochrome c oxidoreductase) [Monday's Molecule #182]. The winner was Stephen Spiro. I think he's a student at the University of Toronto (UT) but it's a campus I haven't heard of in a place called "Dallas."

This week's molecule is a lot less complicated although it's rather strange looking. This molecule has a very specific use. Name the molecule—the common name will do—and describe its use.

Post your answers as a comment. I'll hold off releasing any comments for 24 hours. The first one with the correct answer wins. I will only post mostly correct answers to avoid embarrassment. The winner will be treated to a free lunch.

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.)

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.

Winners will have to contact me by email to arrange a lunch date. Please try and beat the regular winners. Most of them live far away and I'll never get to take them to lunch. This makes me sad.

Comments are invisible for 24 hours. Comments are now open.

UPDATE: The molecule is raltitrexed, also known as Tomudex. It's an inhibitor of the enzyme thymidylate synthase, the enzyme responsible for converting dUMP to dTMP. The drug is effective as an anti-cancer agent since it prevents cell division by blocking DNA synthesis. The winner is Raul A. Félix de Sousa (again).

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
Nov. 21: Vipulan Vigneswaran (honorary mention to Raul A. Félix de Sousa)
Nov. 28: Philip Rodger
Dec. 5: 凌嘉誠 (Alex Ling)
Dec. 12: Bill Chaney
Dec. 19: Joseph C. Somody
Jan. 9: Dima Klenchin
Jan. 23: David Schuller
Jan. 30: Peter Monaghan
Feb. 7: Thomas Ferraro, Charles Motraghi
Feb. 13: Joseph C. Somody
March 5: Albi Celaj
March 12: Bill Chaney, Raul A. Félix de Sousa
March 19: no winner
March 26: John Runnels, Raul A. Félix de Sousa
April 2: Sean Ridout
April 9: no winner
April 16: Raul A. Félix de Sousa
April 23: Dima Klenchin, Deena Allan
April 30: Sean Ridout
May 7: Matt McFarlane
May 14: no winner
May 21: no winner
May 29: Mike Hamilton, Dmitri Tchigvintsev
June 4: Bill Chaney, Matt McFarlane
June 18: Raul A. Félix de Sousa
June 25: Raul A. Félix de Sousa
July 2: Raul A. Félix de Sousa
July 16: Sean Ridout, William Grecia
July 23: Raul A. Félix de Sousa
July 30: Bill Chaney and Raul A. Félix de Sousa
Aug. 7: Raul A. Félix de Sousa
Aug. 13: Matt McFarlane
Aug. 20: Stephen Spiro
Aug. 27: Raul A. Félix de Sousa


  1. Raul A. Félix de SousaMonday, August 27, 2012 9:44:00 PM

    Molecule # 182 is Raltitrexed, or N-[(5-{methyl[(2-methyl-4-oxo-1,4-dihydroquinazolin-6-yl)methyl]amino}-2-thienyl)carbonyl]-L-glutamic acid, an antimetabolite drug used in cancer chemotherapy. It inhibits thymidylate synthase, decreasing the availability of pyrimidine nucleotides for the synthesis of nucleic acids.

  2. No women? Some names I can't tell, but why no females?

    1. No women.

      There are several possible explanations. Do you have a favorite? Are you implying that women are stupid?

    2. Not at all. I'm a woman. And it's a real question. Is this a field that few women enter? Or do women prefer not to enter these sorts of contests? It just strikes me as odd that no women seem to be represented in the winners list, and I wondered why.

    3. I don't know the answer to any of your questions except that in biochemistry there are about equal numbers of men and women students.

    4. Anonymous, you have a lot of class for responding as you have. Hopefully, Larry learned something about not putting thoughts into other peoples minds and determining their intentions FOR them from your exchange. My experience, however, causes me to guess otherwise.

    5. @andyboerger,

      You need a little more experience with sarcasm. You also need to understand that the first comment from anonymous was practically content free but such comments usually imply sexism even if the accusation isn't explicit.

      When people, including you, do not make their intentions clear then one way to get them to reveal their true intentions is to take a stab at guessing. This works really well when your "guess" is so outlandish that the person has to respond.

      I think anonymous understood this very well and she avoided raising the ugly accusation of sexism. Like her, I think it's curious that there aren't more women commenting on science blogs.

      Do you have any thoughts on the matter or are you just looking for more ways to criticize my behavior?

    6. No thoughts about the question itself, just looking for a way to criticize your behavior.
      I am doubtful that anonymous understood your intention very well; I sure didn't, and certainly you may be correct in thinking that I missed the 'sarcasm'. I hope she writes back to let us know.
      However your statement " ...but such comments usually imply sexism even if the accusation isn't explicit" is an admission that you DID, in fact, jump to a conclusion regarding her intent.

      Since not jumping to conclusions is one of the foundational principles of science, you may wish to consider parceling out a bit of that for your non-scientific pursuits now and again.

    7. .. an admission that you DID, in fact, jump to a conclusion regarding her intent.

      I was suspicious so I asked for clarification.

      Is there something wrong with that? It worked with you.

    8. Anonymous here. I am sorry If my original question was construed in any way to suggest I thought Dr. Moran was sexist. I had wished to be brief, perhaps pithy, but instead was "content free", as it turned out. And I am sure he deals on a daily basis with questions that are not merely sarcastic but truly snarky. It just goes to show how easy it is to be misunderstood and how careful we should be to write clearly.

  3. I haven't done this in a while...! Anyway, pubchem page with everything you asked for:

  4. A blogger can't be responsible for who doesn't respond or post comments, what gender they are or any other issue. People respond and comment on a volunteer basis.

  5. Second sentence: true.
    First one: don't think you even believe this yourself.

    Anyway, what about Chrysanthemum? Taking the day off TTC?

  6. Since you bring it up, Rkt, I posted the most controversial of the Darwin-Haeckel posts to date, today. Infanticide