Some organic chemicals are interesting. Some are useful. - C&EN

Nov 6, 2010 - Advertisements that appeared within the print issues of Chem. Eng. News have been included in the C&EN Archives to provide a ...
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Some organic chemicals are interesting. Some are useful. These EASTMAN Organic Chemicals are both. EASTMAN 10209

5 g . . . $ 3.85 25 g . . . 14.65 Converts nonhelical proteins such as α-chymotrypsinogen and β-casein into α-helical configurations. Slightly more potent than Dodecyl Sodium Sulfate, EASTMAN 5967 (10 g., $6.60; 25 g., $14.70). The hydrophobic chain lengths of these anionic de­ tergents help form soluble protein/detergent complexes in acid solutions. / . Biol. Chem. 242, 912. EASTMAN 10128

Tetradecyl Sodium Sulfate

2,3-Dihydro-5,7-dimethyl-lH-l,4-diazepine

5 g . . . $ 3.90 25 g . . . 14.75 Exhibits a transmission band at 2537 A, absorbs at 3130 A, and is transparent above 3500 A. The critical mercury line in meas­ uring fluorescence emission spectra of benzene and derivatives is 2537 A. / . Sci Instr. 43, 341.

EASTMAN 10190

N,N'-Bis(3-aminopropyl)-l,3-propanediamine

5 g . . . $ 3.45 25 g . . . 12.65 Complexes of this compound (6-membered chelation rings) were found to be less stable than those of EASTMAN 4572, Triethylenetetramine (5-membered rings). There also are consider­ able stability differences between chelates formed from the same poly amine. These stability characteristics suggest the possible use of polyamines as ion-exchange resins for separation of transi­ tion metals. Bull. Soc. Chim. Belg. 71, 177.

Perchlorate

EASTMAN 2718

l-Ethyl-2-[3-( l-ethylnaphtho[ l,2d]thiazolin2-ylidene ) -2-methy lpropeny 1 ] naphtho [ 1,2d j thiazolium Bromide 1 g . . . $10.45 5 g . . . 39.00 J-band life detector for extraterrestrial space probes. J-band spec­ tral shifts effectively detect trace quantities of protein (0.002 percent) and other macromolecules. / . Phys. Chem. 68, 1896; NASA CR-466. EASTMAN 10139 5-Chloro-l-phenyl-lH-tetrazole

5 g . . . $ 3.30

25 g . . . 11.75 Suggested for reactions replacing phenolic hydroxyl groups with hydrogen. For example, in reacting p-methoxyphenol . . . the heterooxy ether crystallizes out readily with EASTMAN 10139, and is then subjected to hydrogenolysis to produce anisole in good yield. JACS 88, 4271. EASTMAN 10200

Dimethylthiocarbamoyl Chloride 5 g . . . $ 3.25 25 g . . . 11.55 Converts phenols to corresponding thiophenols. For examplereacting p-nitrophenol with EASTMAN 10200 in dimethylformamide containing a tertiary amine gives a 92% yield of O-p-nitrophenyl dimethylthiocarbamate. Pyrolysis to the S-bond and hy­ drolysis give the p-nitrothiophenol. JOC 31, 3980. EASTMAN 10057

5 g . . . $ 3.85 25 g . . . 14.65 Study fluid flow. EASTMAN 7732 in ethanol can be used to study flow without disturbing flow pattern. Tautomeric shift in molecu­ lar structure of EASTMAN 7732, induced by light flash, yields fine blue dye line which defines flow pattern. Chem. Eng. Sci. 22, 21.

2-(2,4-Dinitrobenzyl)pyridine

EASTMAN 10175 Benzyltriphenylphosphonium Chloride 2 5 g . . . $ 6.70 100 g . . . 23.50 For fluorometric determination of osmium. Microgram quantities of Os are determined by measuring the fluorescence of a spot (0.5 ml) of Os solution that has been added to a paper contain­ ing EASTMAN 10175. Z. anal. Chem. 179, 21. EASTMAN 10215 Piperonylic Acid

5 g . . . $ 4.30 25 g . . . 16.75 Allethrin and pyrethrin synergists. Piperonylic acid and its asso­ ciated amides and esters find use in insecticides as allethrin and pyrethrin synergists. 26 C&EN

l,l,l-Trifluoro-2,4-pentanedione

5 g . . . $ 4.90 25 g . . . 19.05 EASTMAN 8354 l,l,l,5,5,5-Hexafluoro-2,4-pentanedione 5 g . . . $ 6.00 25 g . . . 25.20 Produce chelates separable by gas chromatography. EASTMAN 8354 produces highly volatile compounds for metal identifica­ tion. EASTMAN 8353 slightly less volatile. 4,4'-Bis(heptyloxy ) azoxybenzene $ 6.90 5g. 29.70 25 g . / EASTMAN 10120 4,4 -Bis(hexyloxy ) azoxybenzene 5g. $ 9.10 10 g . 17.05 Nematic compounds for aligning other molecules with the mag netic field of an NMR machine. The NMR spectrum of benzene in one of these solvents, for example, yields 50 lines instead of the conventional one-line spectrum. JACS 86, 5023. EASTMAN

10122

EASTMAN 10231

1-Cinnamoylimidazole

5 g . . . $ 5.80

25 g . . . 22.30 Detects enzyme activity. Older rate assay procedure is replaced by a simpler and more accurate method for direct titration of active site concentrations in enzymes. In this new method, the organic titrant—in this case, EASTMAN 10231 for subtilisin and ρ-Nitrophenyl Acetate, EASTMAN 9020, for α-chymotrypsin—be­ comes the absolute standard. JACS 88, 5890.

Bis (ethyl Acetoacetato) Copper

25 g . . $ 9.60 100 g . . . 35.10 For detecting hydrogen cyanide and cyanogen. A solution pre­ pared by dissolving EASTMAN 10057 and tetra base in chloroform replaces benzidine for detecting a limit of 1 /xg HCN. Analyst 91,282. EASTMAN 7732

EASTMAN 8353

The list of EASTMAN Organic Chemicals has been enriched by the addition of a number of compounds, of which these are representative. We'll send you a complete list of new additions if you wish. Meanwhile, we continue to feature all the familiar organic compounds that all labs use as a matter of routine. Our List No. 44 with its new cumulative Supplement 44-2 itemizes everything. If you don't have it, let us know. All EASTMAN Organic Chemicals, old and new, are avail­ able from the fine laboratory supply houses named below. Or from Distillation Products Industries, Rochester, Ν . Υ . 14603 (Division of Eastman Kodak C o m p a n y ) , at the prices quoted above, which are subject to change without notice. Allied Chemical Corp. Industrial Chemicals Div. W. H . Curtin & C o . Fisher Scientific C o . Howe & French, Inc. North-Strong, Inc. Ε. H . Sargent & Co.

Van Waters & Rogers, Inc. Geo. T. Walker & Co., Inc. Will Scientific, Inc.