• Front Page
   
  
• October ‘99 Issue
   
  
• July ‘99 Issue
   
  
• April ‘99 Issue
   
  
• January ‘99 Issue
   
  
• October ‘98 Issue
   
  
• July ‘98 Issue
   
  
• April ‘98 Issue
   
  
• January ‘98 Issue
   
  
• October ‘97 Issue
   
  
• July ‘97 Issue
   
  

Download the zipped version of installments 1 - 7 of this series, originally published in the Sci-Tech Translation Journal, of the American Translators Association. The file is approximately 87 KB.

Installments 8 - 17 of this series appeared in the July 1997, October 1997, January 1998, April 1998, July 1998, October 1998, January 1999, April 1999, July 1999, and October 1999 issues of the Translation Journal.

 am taking the liberty in this installment of departing temporarily from our incompleted subject of Aromatic Compounds in order to present some other matters that have accumulated that you may find of interest.

Protein folding in the news

Proteins, when folding as described in Part XVII, sometimes make mistakes under stressful conditions and form misshapen moieties; these may possibly lead to brain disorders such as Alzheimer's, Huntington's, and "mad cow" diseases. As reported in Chemistry 3 (4), Summer 1999, biochemists have discovered "protein police" in the human organism, called chaperonins, that intercept these misfolded proteins and set them on the proper course. Without this policing action we would be subject to more widespread nerve disorders.

A major digression—Translating French chemistry to English with style.

A French chemical paper just translated so abounds with pitfalls for the unwary translator that it seems worthwhile to explore the proper nomenclature and terminology to be used, in this translator's opinion.

Locators in French names of organic chemicals normally follow the substituent instead of preceding it. Below are some examples of proper nomenclature (English in italics):

Other terminological differences between French and English, especially in the use of prepositions, also found in this paper included:

Another digression—empirical formulas and Calc./Found calculations

How often have you received a fax with teeny-weeny empirical formulas (e.g. C₁₄H₁₉N₃O₂) but you cannot read the numbers? There is help. Normally these appear in the Experimental Part of a paper along with the calculated percentages of each element (except oxygen).

Compuserve's Science/Math forum contains two QBasic (or QuickBasic) programs I originally wrote for the Commodore 64, named formula.bas and analysis.bas. They are self-explanatory when run.

With formula.bas, you enter the published calculated percentages of all of the elements in the compound (except oxygen), which almost always are in a larger font and are legible, for example C 64.34, H 7.33, N 16.08 for the compound given above, and the program instantly returns the empirical formula, including oxygen. If the result looks strange, there is an option to keep searching for the proper formula.

Conversely with analysis.bas, you enter the faxed empirical formula (which you may have to guess), and the program returns the percentages of each element. This is useful if the calculated percentages of only some of the elements are given, and you have to guess at the faxed formula. The program will confirm or exclude your guess by comparison with the calculated percentages in the document. By trial and error, the correct formula can be found.

If you have difficulty running these Basic programs (or have forgotten how in the Windows Revolution), contact the author at cclaff@cs.com for help.

Abbreviations for substituents

Chemists like to abbreviate almost everything to save pencils and energy. Below is a short list of some of the most common abbreviations for substituents with their spelled-out meanings:

Me	methyl		CH3-
Et	ethyl		C2H5-
Pr	n-propyl		n-C3H7-
Bu	n-butyl		n-C4H9-
Ph	phenyl		C6H5-
Bzl	benzyl		C6H5CH2-
Bz	benzoyl		C6H5C(=O)-
Boc	t-butoxycarbonyl		t-C4H9OC(=O)-
Cbz	benzyloxycarbonyl		C6H5CH2OC(=O)-
Tos (or Ts)	p-toluenesulfonyl		p-H3CC6H4SO2-
Ac	acetyl		CH3C(=O)-
Trt	triphenylmethyl (or trityl)		(C6H5)3C-

Chirality in 3D

A free program that can be downloaded from the Internet, called RasMol, allows chemical formulas to be shown as stick models, ball-and-stick models, space-filling models, or even in stereoscopic 3-D form, in brilliant colors. The 3-D option in particular provides images that are spectacular for those able to view them. Alas, I have e-mailed samples to several renowned colleagues, none of whom are able to cross their eyes voluntarily to see these images in all their splendor. As a broader test, I am attaching images below of (R)-2-butanol and (S)-2-butanol. Each of these consists of two images with slightly different perspectives. When the two images are fused by crossing your eyes, a third image in the center floats in air between the viewer and the screen, and the difference between the two enantiomers can be seen clearly. I would appreciate any positive or negative feedback on your success, via e-mail cclaff@cs.com.

If your eyes will not voluntarily cross, try placing your index finger between the two images of either isomer, focus on the fingernail, and slowly draw your finger toward you while keeping the images in view. A third image should form, and with patience, should come into focus.

I expect to resume discussion of aromatic hydrocarbons in Part XIX.