OF THE MORE THAN 340O EASTMAN ORGANIC CHEMICALS

Bargain . . .

, CH3

Methylcholanthrene (Eastman 4383) is acarcinogen. It's important, but the worldrequires no great quantity of it. We makeit in a 7-step synthesis that takes 2 or 3months because each step must be com-pleted before the next one is started. It'snot the sort of item with which one goes"on stream." That's why, even thoughwe start from relatively inexpensive ma-terials, we must currently price the prod-uct at about $8 per gram. People thus setfree to devote their time more directlytoward their research objectives regardit as a bargain.

Smelling with alarm. . .

CH3(CH2)3SH

n-Butyl Mercaptan (Eastman 437), "syn-thetic skunk oil" in lay language, is ahighly purified compound as we supplyit, much in demand by researchers inthese days of important industrial adven-tures in mercaptan chemistry. Neverthe-less, a minor but interesting fraction ofour output goes to people who want it forits prodigious stench alone. For "sound-ing" alarms in mines too noisy for audi-tory signals, a little bit of it introducedinto the air lines has been found to pene-trate quickly into the inner conscious-ness of every man-jack. We also found a

small market for n-butyl mercaptan indriving rats offproperty, on the principlethat the rodents associate it with their

natural enemy, the skunk. The circum-stances under which the aroma of n-butylmercaptan would be preferred to rats areprobably very special.

Phenol in the river ...

Vitamin C in the can . . .

Cl

O=< =NCIC1

2,6-Dichioroquinonechioroimide (Eastman2483) is a reagent used in testing forphenol in stream pollution investiga-tions. We'll be glad to send you a proce-dural abstract that tells how it will detectas little as one part of phenol per billionparts of water. It works by formation ofan intensely blue compound which hap-pens to be the base of:

C1O=§3=N.jONa

ClSodium 2, 6-Dichlorobenzeneindophenol(Eastman 3463), a reagent much used forthe determination of ascorbic acid invegetables before canning. If you're inthe food business rather than the pollu-tion control business, we shall be equallyhappy to send you an abstract of the pro-cedure described for that.

Don't forget, there are more than 3400other organics available to you fromEastman. Chances are the ones you needare in our List No. 37. If you don't havea copy, there's one waiting for you atDistillation Products Industries, EastmanOrganic Chemicals Department, Roch-ester 3, N. Y. (Division ofEastman KodakCompany).

-gIP| Eastman Organic Chemicals.for science and industry

Also ... vitamins A and E ... distilled monoglycerides ... high vacuum equipment

A..

Wm

Reg. U.Iat. Off.

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ADENYLATES, NUCLEATES,

PURINES AND PYRIMIDINES

Adenine Sulfate

Adenosine-3-Phosphoric Acid (Yeast Adenylic Acid)

Adenosine-5-Phosphoric Acid (Muscle Adenylic Acid)

Adenosine Triphosphoric Acid (A T P)

Adenosine Triphosphate (sodium salt)

Cholic Acid

Cytidilic Acid

CytosineDehydrocholic Acid

Desoxyribonucleic Acid

Glucuronic Acid Lactone

Guanine HydrochlorideGuanosine

Guanylic AcidHypoxanthine

6-MethylthiouracilNucleic Acid (Nucleinic, Ribonucleic)

Sodium CholeateSodium Nucleate

Thymine (5-Methyluracil)Uracil

Xanthine

Use this catalog as a "one stop" source of I a IN/Amino Acids, Vitamins, Carbohydrates,Adenylates, Nucleates, Purines, Pyrimidines,Enzymes, Microbiological and Bacterio- WRITE FORlogical Media, Complete Animal Test Diets YOUR COPYand Ingredients for investigational use. TODAY

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The Chemistry and Technology of FOOD AND FOOD PRODUCTSSecond completely revised and augmented edition in 3 volumes.Prepared by a group of specialists unaer the editorship of MoRRis B. JACOBS.Vol. I: May 1951. 6 x 9. 858 pages, 78 illus., 110 tables. $12.00Vol. II: August 1951. Approx. 960 pages, 54 illus., 397 tables. $15.00Vol. III: October 1951. Approx. 760 pages, 175 illus., 62 tables. Approx. $15.00

Industrial OIL AND FAT PRODUCTSSecond completely revised and augmented edition.By ALTON E. BAILEY. June 1951. 6 x 9. 992 pages, 164 illus., 133 tables. $15.00

THE PECTIC SUBSTANCESBy Z. I. KERTESZ. July 1951. Approx. 640 pages, 46 illus., 66 tables. $13.50

ADVANCES IN ENZYMOLOGY and Related Subjects of BiochemistryEdited by F. F. NORD.Volume XI May 1951. 6x9. 479 pages, 88 illus., 23 tables. $9.00

LABELLED ATOMSBy RAYMOND GLASCOCK. June 1951. 222 pages. (Sigma Book) $1.25

THE CHEMISTRY OF HETEROCYCLIC COMPOUNDSA Series of MonographsARNOLD WEISSBERGER, Consulting Editor.

Six-Membered Heterocyclic Nitrogen Compounds with Four CondensedRings.By C. F. H. ALLEN.June 1951. 358 pages, 7 illus., 40 tables. $10.00 Special price to subscribers $9.00

Thiophene and Its DerivativesBy H. D. HARTOUGH, F. P. HOCHGESANG and F. F. BLICKE.Fall 1951. Approx. 630 pages. Approx. $17.60 Special price to subscribers approx. $16.00

Five-Membered Heterocyclic Compounds with Nitrogen and Sulfur andNitrogen, Sulfur, and Oxygen.By L. L. BAMBAS.Fall 1951. Approx. 450 pages.

Condensed Pyridazine and Pyrazine Rings (Cinnolines, Phthalazines, andQuinoxalines).By J. C. E. SIMPSON.Winter 1951. Approx. 380 pages.

SYNTHETIC METHODS of Organic ChemistryBy W. THEILHEIMER.Volume V (in English): 1951. Approx. 560 pages. Approx. $14.00

AZl books available on approval. Write for our 1951 catalog.

INTERSCIENCE PUBLISHERS, Inc., 250 Fifth Ave., New York 1, N. Y.13May 25, 1951

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Vol. II, Pt. 1, xii, 790 pp.,about $14.00

Theory of Oxidation-Reduction. By LEONORMICHAELS

Thermodynamics and Mechanism of the PhosphateBond. By NATHAN 0. KAPLAN

Transphosphorylating Enzymes of Fermentation. BySIDNEY P. COLOWICK

Dephosphorylation of Adenosine Triphosphate. ByH. M. KALCKAR

Aldolase and Isomerase. By OTTO MEYERHOFKeto Acid Decarboxylases. By BIRGIT VENNESLAND

Amino Acid Decarboxylases. By OTTo SCHALES

Desulfinase. By CLAUDE FROMAGEOTCodehydrogenases I and II and Apoenzymes. By

F. SCHLENKSuccinic Dehydrogenase. By F. SCHLENKHydrogenase and Hydrogenlyase. By W. W. UMBREITFlavin-Containing Enzymes. By H. THEORELL

The Iron-Containing Enzymes. By BRITTON CHANCE,K.-G. PAUL, and H. THEORELL

Copper Oxidases. By C. R. DAWSON and W. B.TARPLEY

Oxidation of Amino Acids. By H. A. KREBS

Oxidation of Amines. By E. ALBERT ZELLER

Lipoxidase or Unsaturated-Fat Oxidase. By RALPHT. HOLMAN and SUNE BERGSTROM

Enzymes in Luminescence. By E. NEWTON HARVEY

Oxidation of Organic Sulfur. By CLAUDE FROMAGEOTAnaerobic Glycolysis, Respiration, and the Pasteur

Effect. By FRANK DICKENSYeast and Mold Fermentations. By F. F. NORD and

SIDNEY WEISS

The complete work consists ot:Vol. I, Pt. 1, xvi, 724 pp., $13.50Vol. I, Pt. 2, x, 637 pp., $12.80Vol. II, Pt. 1, June 1951Vol. II, Pt. 2, August 1951

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