give their all to this phase of the chemotherapy effort. Screening costs h a v e n o w reached $6 million a year, Coghill explains. This amounts to about a quarter of the entire $ 2 5 million cancer chemotherapy program. Nearly half of this, $12 million, is in t h e form of grants for fundamental investigations a t universities and research institutes. Almost $6 million more goes to the pharmaceutical industry and so-called "fringe" industries for their scientific contributions. Some $700,000 helps train people in colleges and universities for work in the field. Finally, administration costs account for about $500,000.
Clathrates Cage Isomers Complex organic compounds selectively trap hard-to-separate isomers, later recovered in high purity FORGING AHEAD with a clathration process, Union Oil researchers are purifying isomers that resist separation by conventional techniques. As described at the A C S National Meeting in N e w York (C&EN, Sept. 2 3 , 1957, page 7 8 ) , t h e process was viewed mainly as an effective w a y of isolating p xylene and ethylbenzene. Although this m a y prove to b e one of t h e most important uses for this process, the m e t h o d has been found to have much broader application, William D. Schaeffer of Union Oil told the recent meeting of t h e American Association for t h e Advancement of Science. The clathrating agent, tetra (4methylpyridino) nickel dithiocyanate, can b e used to separate t h e p-isomer from mixtures of m a n y different disubstituted benzenes, h e says. These include isomers of chlorotoluene, dichlorobenzene, toluidine, nitrotoluene, ethyltoluene, diethylbenzene, and others. This clathrating agent preferentially picks u p t h e p-isomer regardless of t h e substituent groups. The key factors are t h e isomer's size and shape. In this separation technique, t h e solid clathrating agent is a d d e d to t h e mixture of liquid isomers. By a physical phenomenon (not chemical bondi n g ) , t h e p-isomer is selectively t r a p p e d inside t h e clathrating crystals. The crystals are then isolated a n d extracted to recover the isomer. A t t h e same time, t h e clathrate-former is regenerated and can b e used repeatedly.
Initially, research on tetra ( 4-methylpyridino) nickel dithiocyanate centered around its use in isolating substituted benzenes, says Schaeffer in a report coauthored with W. Smith Dorsey of Union Oil and Curtis G. Christian, now with Gaspar Color. Recent work shows t h a t it can also separate isomers of substituted naphthalenes and anthracenes. It is particularly effective in isolating !-methylnaphthalene from t h e 2-methyl isomer. • Different Forms. Tetra ( 4-methylpyridino) nickel dithiocyanate is not t h e only clathrate-former of this type, Schaeffer emphasizes. T h e chemical composition of the three main segments of the molecules (the metal atom, t h e pyridine derivative, a n d the anion) can b e varied to meet specific needs. Preferably, t h e metal component should be divalent. Divalent forms of such transition metals as nickel, cobalt, manganese, and iron are especially effective. T h e hybrid bonding possible with these elements, h e says, may play an important part in determining t h e ability of the complex to form clathrates. Also important is the nature of t h e pyridine derivative in the complex. If it's 4-methylpyridine, p-xylene is selectively clathrated from a mixture of xylenes and ethylbenzene. If it's 4 hydroxymethylpyridine, o-xylene is clathrated. On the other hand, a complex containing 3-ethyl-4-methylpyridine preferentially forms clathrates with m-xylene. In other words, b y selecting the right clathrate-former, t h e chemists can carry o u t exactly t h e separation required. T h e third variable is the anion. Those studied so far include thiocyanate, cyanate, nitrite, chloride, a n d formate. Generally, the most effective are polyatomic anions, such as thiocyanate. • Commercial Future. As yet, Union Oil has no immediate plans for building a commercial plant to separate aromatic isomers b y these clathrating agents. At its research center in Brea, Calif., however, its scientists are actively studying m a n y of these compounds. Much e n gineering and pilot plant work will have to be done before the process proves itself. Nevertheless, this clathrating technique appears to have definite economic and quality advantages over other methods of purifying hardto-separate isomers. Research might well be done on at (Continued
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COMMENT . . . Real progress [in human knowledge] will be made only if all branches of science move forward together in an unbroken front. I would venture to say that there has been no great advance that was not a synthesis of knowledge laboriously accumulated in many different disciplines—a cooperative fusion of many branches of knowledge. For science, like freedom, is indivisible, and freedom in science is just as essential as freedom in any other area of human endeavor. We have encouraged people to be what they will, to pursue any course that seemed good to them. The inherent variability of human nature will inevitably produce sufficient numbers of practitioners to keep each of our scientific pots at the boil. Should artificial barriers be interposed which cause any of those pots to grow cold, not only that particular discipline but all of science will be the loser. In this country, we have emphasized the application of science to the production of things for our material welfare. We have even been accused, from time to time, of confusing scientific achievement with the production of egg beaters and car-washing compounds. I cannot dismiss utilitarian goals as unworthy of scientific application. It is indeed the ubiquitous nature of our scientific effort which stands in contrast with science as practiced in other countries, and particularly in the Soviet Union. American science is not a weapon, its edge sharpened fox military aggression, but a plowshare tilling the peaceful fields of our normal lives. It has been well demonstrated that our capacity to produce in time of peace is our greatest weapon in time of emergency or war. Hence, strength in war, strength in peace, and strength in science become synonymous. CRAWFORD H. GREENEWALT, president of D u Pont, before Sigma Xi and Scientific Research Society of America at American Association for Advancement of Science, I n dianapolis, Dec. 27, 1957. JAN.
13,
1958
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RESEARCH
least several thousand different isomers for possible separation by this technique, says Schaeffer. "The work so far has been largely empirica"' he points out. " W e pick a clathrating agent at random and see how it works. In the future, we hope to b e able to tailor-make the exact complex needed to perform a specific separation."
Briefs . . • Penicillinase, specific treatment for penicillin reactions, will b e introduced to the medical profession this week by SchenLabs Pharmaceuticals under the name Neutrapen. Penicillinase is the enzyme obtained from cultures of B. cereus; it neutralizes circulating peni-
NOMENCLATURE b y LEONARD CAPELL
"In 1949 the Commission on Inorganic Chemical Nomenclature of the International Union of Pure and Applied Chemistry (IUPAC) apThe controversy in America over proved 'niobium' as t h e name for the name for element 41 contin- element 41 a n d 'wolfram' for eleues. To try to help clear the air on ment 74 ( tungsten ). T h e National this timely subject I have requested Research Council (NRC), American a statement by the long-time Chair- representative institution in IUPAC, man of the ACS Committee on No- protested the recommendation of 'wolfram,' but accepted 'niobium,' menclature. This follows: "The name 'columbium,' pro- both on the grounds of majority usposed by Charles Hatchett, the dis- age and in a give-and-take spirit. "Consistent with its general atcoverer of this element in 1801, gained general acceptance in t h e titude towards international standUnited States, but in European ardization, the AMERICAN C H E M I countries the name 'niobium' pro- CAL SOCIETY went along with NRC, posed by H. Rose in 1844, when he official action having been taken in thought h e h a d discovered a new 1951. British action w a s the same element, came into common use. A (British and American chemists long story could be told of events cooperate in nomenclature work) which affected the situation, such and IUPAC rescinded its approval as the confusion of element 4 1 with of "wolfram." tantalum, but the point of signifi"Now it appears that the acceptcance here is the fact that America ance by most American chemists of has virtually stood alone in accept- 'niobium' has not been paralleled ing 'columbium.' in metallurgical and like fields. " There is almost universal agree- This is understandable because of ment that the discoverer of a chemi- the growing commercial aspects of cal element should have t h e right the metal in question a n d because it to name it. There are other con- is natural that chemists should siderations of real significance, how- listen more closely to I U P A C and ever, in the growth of language. to ACS rulings. In commercial One of these is usage. Predomi- circles it is less easy t o change a nant usage, no matter what leads name. More than one trade name to it, is much more difficult to stem for a given product is not uncomif standardization is attempted than mon, but the use of more than one is more limited usage. In science in generic term is an extra handicap. particular, standardization is often "One group in the metal field has very desirable. Science is interna- taken t h e position that 'the questional a n d efforts for international tion is open' and that, until there standardization of the names and is 'a positive stand,' 'columbium' symbols of elements are not prop- will be used exclusively 'to minierly taken lightly. Such efforts call mize the confusions.' for a cooperative attitude, a spirit "Cannot chemists properly claim of give and take. jurisdiction as to the standardiza-
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vs. /#! Columbium"
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i 95 8
cillin itself, thus counteracting the cause of allergic reactions. • Cancer research grants by the Damon Runyon Memorial Fund totaled $986,770 between D e c . 1, 1956 and Nov. 30, 1957. It was distributed in 801 grants a n d 400 fellowships in 231 institutions in the U. S. and 18 foreign countries.
tion of the names of the fundamental chemical entities known as t h e elements? H a s not IUPAC resolved t h e dilemma as to naming, with N R C a n d ACS sanction for America? I n t h e use of 'columbium,' a segment of America is t h e one soldier who is out of step. "More than the name of a single substance is involved for chemists. T h e names of chemical compounds containing element 41 are influenced b y the name of the element. Compounds become increasingly numerous. T h e recording of information concerning compounds is done b y formulas as well as b y names. Chemical Abstracts cannot well vacillate in record keeping. ACS cannot control IUPAC action nor well go against an agreement with British chemists. "It does seem that the official naming dilemma has been resolved. Should not usage follow? May w e not earnestly h o p e for this? "As it gains in commercial value in America, element 41 will gradually gain in such value elsewhere. In science the world is moving forward in useful standardization. In commerce the world grows smaller. T h e world-wide situation cannot b e cleared up by a stand now for 'columbium' in America. For t h e good of the most people and for t h e long-run benefit of all will not general acceptance of the already officially accepted international standardization ruling b e wise?" E . J. CRANE
How Many? Periodically t h e Chemical A b stracts Service is asked the questions: How many chemical compounds (sometimes limited to organic compounds) are there? H o w many n e w compounds appear in the literature each year? Do you have a guesstimate?
