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Monday, October 01, 2012

Monday's Molecule #188

Last week's molecule was N-formylmethionyl-tRNAfMet [Monday's Molecule #188]. Only three people came close. The winner was Mikkel Rasmussen.

Name these molecules. One of them has a well-known common name that you have to include in your answer. The other one also has a common name but you don't have to find it. You have to give the complete formal names of each molecule. Do you know the significance of these two molecules?

Post your answer 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 now open.
UPDATE: The molecules are cis Δ9-octadecanic acid (oleic acid) and trans Δ9-octadecanic acid (elaidic acid). This week's winner is John Runnels. He should email me to arrange a meeting.

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
Sept. 3: Matt McFarlane
Sept. 10: Matt Talarico
Sept. 17: no winner
Sept. 24: Mikkel Rasmussen
Oct. 1: John Runnels


  1. The molecule on the left is oleic acid, (9Z)-octadec-9-enoic acid.

    The molecule on the right is elaidic acid, (9E)-octadec-9-enoic acid.

    Oleic acid is a monounsaturated fat. Elaidic acid is the trans isomer of oleic acid. Monounsaturated fats are often considered to be healthier than saturated fats.

    The cis isomer is often considered to be healther than the trans isomer.

    John Runnels

  2. The left one is oleic acid, or (9Z)-Octadec-9-enoic acid. The right is elaidic acid, or (9E)-octadec-9-enoic acid, the trans isomer of oleic acid. Oleic acid is a common fatty acid in many plants and animals, usually found in triglycerides. Elaidic acid is found in hydrogenated veggie oils.

  3. Hi Larry,

    cis-9-Octadecenoic acid
    Oleic acid
    occurs naturally in various animal and vegetable fats and oils.
    octadec-9-enoic acid
    Elaidic acid
    found in hydrogenated vegetable oils

    Glyn Tompkinson

  4. (9Z)-Octadec-9-enoic acid and (E)-Octadec-9-enoic acid, better known as oleic and elaidic acid, respectively. Oleic acid is used in soap and has been claimed to be the cause of the hypotensive effect of olive oil, while elaidic acid, the trans isomer formed industrially by partial hydrogenation, has been much maligned in the media for raising LDL and lowering HDL cholesterol.

  5. Oleic acid and its trans isomer elaidic acid.

  6. Left one:
    (9Z)-octadec-9-enoic acid
    cis-9-Octadecenoic acid
    Oleic acid

    Right one:
    (E)-octadec-9-enoic acid
    trans-9-Octadecenoic acid
    Elaidic acid

    Oleic acid is very common in animals and plants (as triglyceride). Its sodium salt is used as a major component of soap.

    Arek Wittbrodt

  7. (9Z)-octadec-9-enoic acid is oleic acid the other is (9E)-octadec-9-enoic acid less well known than oleic with a common name of elaidic acid.

    Oleic acid (as triglyceride esters) compose the majority of olive oil. It's reported health benefits include the possible slowing of the progression of adrenoleukodystrophy (ALD), a fatal disease that affects the brain and adrenal glands. More commonly oleic acid may be responsible for the hypotensive effects of olive oil.

    Elaidic acid increases Cholesteryl ester transfer protein (CETP) activity, which in turn raises VLDL and lowers HDL cholesterol.

  8. They're the cis and trans isomers of a fatty acid.

    Left one is Oleic acid/Oleate, or IUPAC name cis-Δ9-Octadecanoate.

    Right one is the trans-isomer of the same fatty acid, Elaidic acid, or trans-Δ9-Octadecanoate. A common trans-fat found in various hydrogenated vegetable oils.

    Not undergraduate.
    /Mikkel Rasmussen

  9. On the left is cis-9-octadecenoic acid, whose common name is oleic acid.

    On the right is trans-9-octadecenoic acid.