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RESEARCH

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N O M E N C L A T U R E

by AUSTIN M. PATTERSON1

Esters of Polyols S. G. Brooker of Abels, Ltd.,

Newmarket, Auckland, New Zea­land, asks about the naming of esters of glycerol. Should we, for example, say "glycert/Z monoste.ar-ate" or "glycerol monostearate?"

The International Union has dropped "glyceryl" from its list of radicals because of its ambiguity. Tt has been used to mean not only C^Hr-, (trivalent) bu t also C 3 H r r ( O H ) (bivalent) and C 3 H 5 ( 0 H ) 2 (univalent) . The names "glycerol monostearate," "glycerol distear-ate," and "glycerol tristearate" are clear and in good standing. In general the esters of polyols may b e named in the same way; as, glycol dinitrate, resorcinol mono-acetate. The CA indexes still use "glyceryl" occasionally, but only for the trivalent radical and then only in special cases, not for naming glycerol esters.

Analyte D E A R SIR:

I have a suggestion to make re­garding the coinage of a new, and as it seems to me, much-needed word in quantitative analytical chemistry.

There is not, as far as I am aware, any short word denoting "the substance being analyzed for" in use, nor have I seen one pro­posed. Much circuitous language has been employed in books, and papers to convey this meaning. When the substance sought is defi­nite, it may be named, bu t this procedure does not keep t h e main idea before the reader, nor does it avail when a general discussion of analytical procedures of wide appli­cability is undertaken.

Such a word would find its chief use in quantitative analysis, since the word "unknown" serves satis­factorily in qualitative discussions. However, in quantitative work i t is the amount and not the identity of the substance which is unknown, and hence to refer to the substance being estimated as an "unknown"' is rather inappropriate.

My proposal is that die word "analyte" be understood to convey

* 2 2 1 North King St., Xenie. Ohio.

the above meaning. I t i s short, and, to me, suggests the idea. T h e new word would, of «ourse, be available as an alternate for "un­known" in qual i tat ive analysis, but would express an idea for which there is no single word in quanti­tative analysis.

Possibly objections can b e raised to my choice of word-, o r other more suitable words proposed, but none occur to m e a t paresent. In any event, it seems to me that a difficulty certainly exists, and tha t some name should h e croimed. CRΑΥΤΌΝ Μ. CRAWFORD Los Alamos, Ν. Μ.

Have our readers any comments?

Betaines Again Noting Wayne L. St. John's pro­

posal (C&EN, Oct. 10, p a g e 4288) for naming betaines, J. IF. Bunnett believes that t he spirit of the St. John system can be preserved and objections to it met, if tlhe canonic group is named by the system pro­posed b y Bunnett in «3&ΈΝ 32, 2320 ( 1 9 5 4 ) . The following names would result:

( C H 3 ) 3 N + C H 2 C O O -<x- ( tr imethylammonio) acetate

( CH 3 ) 3 N + 0 H , C H : C H C ' O C r y-(trimethylammonio ) crotonate

( CH3) 2 S + C H X H 2 C O O -β- ( dimethylsulf onio ) propionate or 3-( dimethylsulf omio) pro-panoate

CBH5N+CH ( C H 8 ) C O 0 -a~ ( pyridinio) propionate

The use of t h e "io" ending in­stead of "ium" seems to* us an im­provement; b u t we «question whether each name sho»Tdd not be spelled as one word ratlher than as two.

And Now "Isourecs" In our June 6 issue (rpage 2433)

we rashly stated that "europia" seems to be the only cheinical word that contains all five v o x e l s and is shorter than "thiourea." Benjamin D. Berkman of American* Cyanamid confutes us wi th the equally short word "isourea."

5 2 6 2 C & E N DEC. 5, 1955