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I just accomplished something at work that I thought I couldn't do, so I am rewarding myself by posting to this forum for the first time.
Inventing the word "dextrocentric" seemed obviously necessary to me when my daughter started using her hands for things beyond the random infantile waving and poking of self in eye: i.e., eating, drawing, using scissors, etc. She was obviously left handed, and suddenly my consciousness was raised about how many processes in our daily lives use tools that operate on the assumption that the person using them is right handed. And I say, when a phenomenon exists, it needs a name.
When I used the term in speaking to one of my co-workers, he thought I was talking about dextrose at first. I told him the words were related, that dextrose is probably a right handed molecule. He asked me how you could tell a molecule was right handed, so I suggested he watch it write a check. I don't remember enough chemistry to know how a molecule can be right handed, I just know it can.
This is my bid for immortality.
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Joined: Dec 2000
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Carpal Tunnel
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Carpal Tunnel
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Welcome, birdfeed (I like the handle).
I am just learning about the complexity of isomers due to a post by wwh (familiarly know as Dr. Bill). I had known only what I think of as D-isomers and L-isomers for right and left handed versions of complex molecules that can be oriented in two different ways. There are other isomer pairs, notably endo and exo isomers, but them I have no idea what differentiates them. It gets kind of technical on the molecular level. As far as I know the choice of handedness in the designation of these molecules is purely arbitrary.
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Joined: Nov 2002
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Joined: Nov 2002
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Thanks. Yer own self-described better half put the idea of "birdfeed" in my head. Having read your response, I must say I vastly prefer "right-handed" and "left-handed" to the non-hyphenated versions I used.
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Joined: Dec 2000
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Carpal Tunnel
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self-described better half
We're a team. Which of us is the better half varies from situation to situation. Or so she permits me to believe
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Carpal Tunnel
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Deaar Faldage: If I remember correctly, Pasteur discovered optical isomerism, and made
several of the original contributions thereto. I'll try to see if I can find anything worth
posting.
The sites I found were rather volminous to quote from, you can copy and paste from this:
1.Optical isomerism - Wikipedia - ... First discovered by Louis Pasteur in the nineteenth
century, the study of optical isomerism is called stereochemistry. Optical isomers ...
http://www.wikipedia.org/wiki/Optical_isomerism search within this site
2.Stereoisomerism - ... Optical Isomerism. ... the plane of polarised light and this was known as
optical activity. Louis Pasteur discovered that when 2,3-dihydroxy (tartaric) acid was ...
http://www.users.globalnet.co.uk/~freya01/stereoisomerism.htm
3.ISOMERISM AND STEREOCHEMISTRY Jack DeRuiter I. Basic Principles (PDF) - ...
Pasteur further demonstrated that the left- and right-handed crystals were mirror images of each
other ... Figure 3. Tetrahedral geometry and optical isomerism III ...
http://www.auburn.edu/~deruija/pdastch1.pdf
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Thanks, Dr. Bill. I'd like some good stuff on this whole subject. My guess on endo and exo isomers is that they have, respectively, radicals pointing in and out of the basic structure. ¿Qué no?
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Dear Faldage: I am completely ignorant about endo- and exo- isomerism. Here's a bunch
of sites:
1.REACTIONS IN SUPERCRITICAL CARBON DIOXIDE - ... Alder reactions. It is well known
that many Diels-Alder reactions result in formation of variable mixtures of endo- and exo-isomers.
...
http://www.chem.leeds.ac.uk/People/CMR/da.html search within this site
2.exo/endo-7-NORCARANOL - ... 7. The exo/endo ratio is 6:1; the exo and endo isomers
show characteristic triplets in their nmr spectra at d 2.9 and 3.1 ppm, respectively. ...
http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=CV5P0859 search within this site
3.E033: Troubles With Isomers Of (Isodicp)Ticl<Sub>3</Sub> - ... The two isomers of
(isodiCp)TiCl 3 have similar unit cells in the orthorhombic crystal system: endo with a = 9.134(1),
b = 12.328(1), c = 10.314(1) Å, and exo ...
http://www.hwi.buffalo.edu/ACA/ACA97/abstracts/text/E033.html search within this site
4.electronic poster - ... as shown in Scheme 3. Thus condensation of the endo- anhydride with ...
Interestingly, attempts to extend this chemistry to the exo-isomers of compounds (10) and ...
http://www.ch.kcl.ac.uk/kclchem/staff/mno/poster.htm search within this site
5.Chapter 2 Stereochemical Principles Isomers (PDF) - 1 1 Chapter 2 Stereochemical
Principles Problems: 1 (4 pts), 2 (4 pts), 5 (2 pts), 6 (6 pts), 10 (7 pts), 16 (4 pts), 18 (3 pts) 2
Isomers * Same formula ...
http://www.cns.uni.edu/~macmilla/carroll/Carroll02.pdf search within this site
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Carpal Tunnel
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back to the matter at <ahem> hand, google finds no hits for dextrocentric; but does turn up this for dexterocentric, from Feb., 2000: http://www.dailyemerald.com/archive/v101/2/000224/letters.htmlI don't know which I like better.
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Joined: Dec 2000
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Unfortunately, these all look like sites that expect you to know what they are before you enter.
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Joined: Dec 2000
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Carpal Tunnel
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Carpal Tunnel
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