Tuesday, May 3, 2011

A taste of the good ol' days: ancient CAS Online

Goodness, it's just that easy.
Photo credit: chembase.com
I was flipping through some older literature today, and found a wonderful reminder from March's "Advanced Organic Chemistry" (2001, 5th edition) of the torture pain sheer agony effort it took to search through SciFinder before the graphical interface arrived.
  • "The procedure for building a structure can be long and complex, if the structure is large and complex, but the commands are simple. We will illustrate by building the structure for 3-ethylpiperidine, which uses the most important commands.
  • We begin with the command STRUCTURE. [snip]
  • We will then get the prompt ENTER (DIS), GRA, NOD, BON OR ?
  • GRA is used for putting in rings or chains. We enter GRA R6, DIS [snip]
  • We wish to introduct a two-atom side chain (the Et group), so we enter GRA 3 C2, DIS [snip]
  • [a bunch of clarifying text]
  • To get 3-ethylpiperidine, the atom in the 5 position must be nitrogen. A C can be changed to another element by using NOD (for node), so we now type NOD 5 N, DIS. This changes C-5 to N-5, giving all the atoms in their final positions. 
  • However, the structure is still not complete because the bonds have not been specified [snip], so we type BON ALL SE, DIS and we get our final structure in Figure A.1. 
  • At this point we type END, and get L1 STRUCTURE CREATED. 
Oh, you want to search this structure? Forget it. My fingers are cramping. 

Young ones (myself included), if you ever get tired of older chemists railing about how hard they had it back in the day, think to yourself "they didn't have a structure editor in their SciFinder" and cut 'em a break. (a little one) 

3 comments:

  1. This reminds me of library searching using Dewey decimal and card catalogues (pre-1995). OK, I'm in the "900" block, so I want 976.A4, under "Thompson", let's see, Thomas, Thurman, Thermos....oh...someone has that book out. Nuts.

    ReplyDelete
  2. I remember those days, although I never actually used SciFinder that way. My grad school didn't have access to SciFinder, and then when I went into industry, there were information specialists who did this for you! You would send the information to the library and you'd get back the results in a few days. Once SciFinder and Beilstein became easier to use, those jobs disappeared.

    But I think the biggest difference is that SciFinder typically wasn't used on a routine basis. It was only something you would use to check literature for patent purposes or if you ran into a major problem with your project. Most of the time, you (or your project leader) were expected to have this stuff in your head, or at least know where to find it in the literature. A major change compared to a few years later, when everyone searched through SciFinder even for relatively routine reactions.

    ReplyDelete
  3. What happens if your PI dies mid-post-post-doc?

    http://chronicle.com/forums/index.php/topic,77319.0.html

    ReplyDelete

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