COMMENT
on some EASTMAN Organic Chemicals
EASTMAN 9 5 0 3 2,4-Dinitroso-l,3-naphthalenediol
This has demonstrated, bare-eyed, the presence of 10"9 g. of iron in one of those acrylamide gel discs that make up the characteristic disc-electrophoretic fingerprint of a protein mix. The reagent was devised by a very smart man we know. He and a buddy thought up disc electrophoresis in the first place. Last winter he vacationed on Bimini, which offers the Lerner Marine Laboratory as one of its charms. After a quick snooze in the sun, he sought exercise first in skin-diving and then in phylogeny. He had his disc-electrophoresis kit along. An amazing observation resulted from a colleague's offer of octopus serum. The protein pattern resembled the mammalian serum pattern even more than the uncanny octopus eye resembles the mammalian eye. Excited by this new evidence of interphyletic convergence, our smart friend upon his return home prepared to clinch it by proving that the disc corresponding to the iron-bearing protein transferrin in mammals would in the mollusk's serum respond selectively to a sufficiently sensitive reagent for iron. Of iron reagents there are plenty ; none he could find, however, performed as well under the special conditions encountered in disc-staining as the one named above, which he extrapolated from the literature, his experience, and the sheer force of reason. After he told us what it was, we made him some that he found better than his own product. This we now offer. We also offer the other EASTMAN Organic Chemicals needed in disc electrophoresis. Separately and without charge, we continue to offer the authors' description of the theory of disc electrophoresis and their illustrated directions for the procedure, now supplemented for iron. Ours has been a proud role in publicizing their method around the world. Tt is distressing to have to report that no publication on cephalopod phylogeny is in immediate prospect from our friend. Not only is he smart, but also frank, lucky, and grateful to have learned in time of some misbegotten horse serum that he was confusing with the colleague's octopus samples.
EASTMAN 9151 1,1,1,3,3,3-Hexamethyldisilazane (CH3)3SiNHSi(CH3)3 We use it ourselves in our research on oil-soluble vitamins and food monoglycerides. It makes them volatile. Almost any hydroxyl-containing organic molecule that is not a high polymer becomes airborne at its kiss.* Almost any such compound one tries seems to turn into an ideal subject for sharp-cutting gas-liquid chromatography when made a trimethylsilyl ether. It is like replacing the proton of each hydroxyl with a bunch of balloons that protect it and lift it away from the grasp of hydrogen bonds. Maybe we would have missed the chance to base a business on high-vacuum distillation of heat-labile substances if silazanation had been discovered 30 years ago. Silazanation, if the truth were known, drifted into our ken * We kiss as follows: t o 10 mg. of material, add 1.0 ml. of Pyridine (EASTMAN 214), 0.2 ml. of EASTMAN 9151 and 0.1 ml. of Chloroirimethyhilane
(EASTMAN P8710).
Shake for 30 sec. a n d let stand for 5 min. while NH4CI precipitate settles. Take aliquot for G L C . T o save for future reference, continue washing with alternate 5 ml. portions of water a n d Hexane (EASTMAN PI 135) until pyridine odor is gone.
in the late summer of '63. A chemical news story told that a team at a medical school in Pittsburgh was having great good luck purifying carbohydrates and related polyhydroxy compounds by GLC with the trimethylsilyl derivatives. Without further ado we turned to the bench and enjoyed the same good luck with it on our vitamins and monoglycerides. Others had spectacularly good luck in their fields. Papers are popping all over on GLC of silazanized fatty acids, steroids, plant sterols, bile acids, alkaloids, barbiturates. There has also been one {Ann. 659, 190) on silazanation for peptide synthesis. The best is yet to be, now that we announce the easy availability of EASTMAN 9151.
And to whom are we all indebted? In part, to the U. S. Congress for voting tax money to help the coal industry compete in liquid fuels. In carrying out this mandate of the people, the U. S. Bureau of Mines found trimethylsilyl derivatives useful in analysis, identification, and purification of phenols and pointed out the applicability of GLC to the problem. The whole bit, including catalysis of the reaction by a little chlorotrimethylsilane and explanation of why this works, comes from the Bureau. True, the Bureau was probably being influenced by organosilicon research sponsored by a glass company and two other big companies that happen to make silicones. A man from one of the latter had gone so far as to suggest that trialkylsilyl derivatives of alcohols and phenols are low-viscosity liquids, easy to prepare, thermally stable, resistant to air oxidation, and easy to hydrolyze. There is also another use for EASTMAN 9151 in GLC. It inactivates the support materials against adsorption of the gaseous solute in competition with the stationary-phase liquid. This was discovered in the non-political, non-commercial, prestige-covered halls of Cambridge University, alma mater to Isaac Newton. The boys were grinding up firebrick and taking their lead from the U. S. Bureau of Mines on the affinity of hexamethyldisilazane for the hydroxyls in the stuff. EASTMAN 3512 Methoxyacetonitrile CH3OCH2CN EASTMAN 9 3 5 4 Methoxymethyl Acetate CH 3 COOCH 2 OCH 3
These two items are offered under the same sales strategy employed in your friendly neighborhood hardware store. They make it easy to do a job one normally puts off for fear it might not be as easy as it looks. They are sure to come in handy for adding reactive groups to a benzene nucleus. EASTMAN 3512 condenses with phenols in the presence of HC1 and ZnCh. For example, in running a custom synthesis of a certain estrogen we react EASTMAN 3512 with resorcinol to get CH3OCH2C=NH which we then hydrolyze OH OH
OH Our fellows use EASTMAN 9354 to make benzylacetates or benzyl alcohols from compounds like 1,3,5-trimethyIbenzene. It puts -CH2OCOCH3 on the ring between methyl groups. Alkaline hydrolysis knocks off the acetate from the benzylacetate when the benzyl alcohol is wanted.
Distillation Products Industries is a division of Eastman Kodak Company ·
ANALYTICAL CHEMISTRY
OH
in dilute HC1 to get
Orders, requests, and price inquiries are handled by Distillation Products Industries, Rochester, N. y. 14603. Local distributors carry large stocks of EASTMAN Organic Chemicals.
48 A
CH3OCH2C=0
DPI
