. . . AMONG SOME 3 8 0 0 Suggestion from East Berlin May we have your attention, please, to a 411-word essay on lipase? Ostensibly it advertises an Eastman Organic Chemical, Phenyl Laurate (East man 7885). To be sure, 25 grams of this compound may actually be purchased for $3 from the address given at the bottom of the page. Because of difficulty in drap ing intellectual dignity around a bottle worth $3, it serves our purpose to issue the large, round declaration that enzymes are the most important subject on earth. Does not their interplay govern all' activ ity in the biosphere, including that in the cerebra of men of business and science? Of course. Permit us now to narrow the scope to one class of enzymes, the esterases. Li pases are esterases that split fats. Other Suggestion to A m e s , I o w a Cyanamide (note the " e " ; very, very, VERY important) is not stable. On that, Walter R. Hearn of Iowa State University and we agree. Dr. Hearn is interested in guanidation of amino groups in peptides and protein, i.e. RCHCOOH — » NH2
RCHCOOH NH )C=NH H2N
This can be accomplished with cyana mide ( H 2 N C ^ N ) and some of its de rivatives. There was a problem. In think ing of well known chemical houses with whom to take up a problem involving cyanamide, one doesn't necessarily think first of us, but Dr. Hearn had somehow formed the impression that we were friendly fellows. Another factor which might have contributed to his decision to write us was the fact that six bottles of Suggestion at Pittsburgh, Pa.
esterases split simple esters of fatty acids. Lipases occur in certain animal organs and plant tissues. Although other ester ases are fed into the mammalian blood stream from the liver, the lipase content of the blood serum is very low unless the duct of the pancreas is closed off. To demonstrate and estimate an ester ase, one gives it something (hereinafter designated a substrate) to split under fixed conditions, and one compares the amount of split product against a blank. Olive oil has been the standard substrate for lipase. The fatty acids released are ti trated against sodium hydroxide. On page 221 of a certain book it says that this will work for lipase in blood serum. The measurement offers difficulties when the serum lipase level is normally low. Jt be comes a poor subject for wit when some foul derangement in the human machine cyanamide in his stockroom, which showed melting points as much as 150° higher than they were supposed to, hap pened to bear our PI995 label. Well, sir, we did prove friendly. We pointed in a friendly way to the "Practical" on that label as an open ad mission that the Cyanamide probably wasn't all cyanamide, though it had been originally. We said that to retard dimerization we kept our stock of Cyanamide under refrigeration and advised him to do likewise. We suggested he reclaim the undimerized portion of his stock by dissolving in ten parts or more of ether, filtering off any dimer, and concentrating the filtrate below 35°C at all times. We warned him not to dissolve in less ether because he'd get dimer into solution. We also answered his question of why our Cyanamide (Practical) was 25 times as expensive as one of the cyanamide de rivatives that he used, our S-Methyl-2thiopseudourea Sulfate (Eastman 1231), HOCOCH-> lu
CH 2 COOH NCH 2 CH 2 N
ORGAN,CS raises the level to a point easy to measure. The subway from East Berlin has brought out of Humboldt University there the suggestion (Clin. Chim. Acta. 4, 221) that phenyl laurate nicely liberates phenol in colorimetrically measurable quantity when acted upon by serum li pase. Soon after the news reached us, we prepared this compound for sale because it has good shelf life, where other pro posed substrates all too soon split by themselves untouched by lipase. Then we took a different subway to Brooklyn, Ν. Υ., to chat with a biochemist who told us of a considerable improvement in the phenyl laurate procedure. Whoever will write name and address and the last three words of the preceding sentence on a post card addressed to us will receive an abstract of the Brooklyn procedure as soon as it is published. /NH2C=NH\ H 2 SO 4 V
SCH 3
)2
by explaining we did not make the latter from pesky cyanamide. We further suggested how he might ob tain the oxygen analog of this isothiouronium salt which he preferred for some of his guanidation operations. We re ferred him to a paper by one of our cousins at Kodak Limited in England (Journal of the Chemical Society, 1955, 3551), where cyanamide is by-passed by smooth methylation of urea with methyl toluene-p-sulfonate to give a good yield of readily isolated product. Finally we proposed that if he did not want to try this himself we would, for 96 bucks, cash on the barrelhead, deliver to him 500 grams of O-methyl-2-pseudourea sulfate. That ought to teach Walter R. Hearn of Ames, Iowa, not to begin a letter with, "Since you have not acknowledged my letter of September 22, 1 thought perhaps you had gone out of business." have this reagent, they will encounter no mere bland smile. We will be able to reply, "Yes, sir, here it is, labeled a,a'-(Ethylenedinitrilo)di-o-cresol and des ignated Eastman 8019." And that is exactly what we were in a position to do that day. The only trouble was that while many people did flock to our booth and talked of many things, not one soul as much as mentioned bissali cylideneethylenediamine.
When we read the advance program for HOCOCH2/ \.CH 2 COOH this year's Pittsburgh Conference on When the former, in slightly alka (Eastman Analytical Chemistry & Applied Spec line Ν,Ν-Dimethylformamide troscopy, we decided on a coup. One of 5870), chelates Mg ions, it becomes highly the papers was to state an interesting fact fluorescent. The excitation maximum oc about bissalicylideneethylenediamine, curs at 355ηιμ, and the emission maxi occurs at 439ιημ. A sensitivity of 7 χ which stands in relation to the well known mum 10"5 micromole of Mg per ml was men chelating agent EDTA as tioned. Same old stand—Distillation Products This time, said we to ourselves, when
