White Amorphous Powder Research Articles

Low-temperature chemical synthesis of nanocrystalline KTiOPO4

Nanocrystalline KTiOPO4 powders were prepared through a chemical process. This process involved the hydrolysis of KOOCCH3 · 2H2O, Ti(OC4H9)4, and PO(OR)3 to produce a homogeneous solution. A gel was formed by the partial evaporation of this solution. After the gel was decomposed at 450 °C, white amorphous powder remained. On calcinating up to 550 °C, the amorphous powder began to transform into nanocrystalline KTiOPO4 powders with an average particle size of 30–50 nm. The KTiOPO4 powders were investigated through x-ray diffraction, infrared spectroscopy, and transmission electron microscopy studies.

Methanstibonsäure / Methanestibonic Acid

Methanestibonic acid is obtained by hydrolysis of tetraalkoxymethylstiborane or by oxidation of dimethoxymethylstibine with H2O, in a mixture of methylenchloride and alcohol at 0 °C as a white amorphous powder. Reaction of the acid with 2,3-dimethyl-butane-2,3-diol yields MeSb[OC(Me),C(Me)2O]2, and with sodium hydroxide a sodium salt Na2[MeSb(OH)3O]2 · 6 H2O is obtained.

Aladapcin, a new microbial metabolite that enhances host resistance against bacterial infection. Production, isolation, physico-chemical properties and biological activities.

We have constructed a new screening system for detecting microbial products that enhance host resistance against bacterial infection. It was found that a new compound with such activity is produced by a soil isolate classified as Nocardia sp. SANK 60484. The compound was isolated from the culture filtrate of the organism and named aladapcin after its amino acid composition. Aladapcin was obtained as an amphoteric white amorphous powder with the molecular formula, C13H25N5O5. It consists of 2 mol of D-alanine and 1 mol of meso-diaminopimelic acid. From the analysis of IR, 1H NMR and FAB-MS spectra, the structure was assigned to be a tripeptide. Aladapcin enhanced host resistance against an experimental Escherichia coli infection in mice at doses ranging between 1 and 100 micrograms/kg.

Exploratory ring‐opening polymerization. XIIL ring‐opening polymerization of 2‐vinyl cyclic sulfones

Abstract2‐Vinyllhiolane‐1,1‐dioxide (Ia) and 2‐vinylthiane‐1,1‐dioxide(Ib) have been prepared and polymerized with free radical initiators to obtain poly(sulfonyl‐hex‐2‐enylene) (IIa) and poly(sulfonyl‐hept‐2‐enyIene‐co‐2‐vinylthiane‐1,1‐dioxide) (IIb), respectively, via a ring‐opening mechanism. Structures of the polymers are supported by infrared and 1H‐NMR spectroscopy. Poly(sulfonyl‐hex‐2‐enylene) was insoluble in ordinary organic solvents, but soluble in concentrated sulfuric acid or trifluoroacetic acid, and was white amorphous powder, softening at 168°C. Degradation occurred at 294°C under N2. Ia copolymerized with certain vinyl monomers, such as ethyl acrylate, but its copolymerization behavior was different from those of normal vinyl monomers.

Studies on aculeacin. I. Isolation and characterization of aculeacin A.

Aculeacin A, a new antifungal antibiotic was isolated from the mycelial cake of Aspergillus aculeatus M-4214. The antibiotic is a white amorphous powder soluble in lower alcohols and hardly soluble in other organic solvents or water. Aculeacin A gave palmitic acid and five ninhydrin-positive products including theonine, hydroxyproline upon acid hydrolysis. The antibiotic showed a potent activity against molds and yeasts, but exhibited no antibacterial activity. Aculeacin A has relatively low toxicity in mice.

Studies on colistin nonapeptide derivatives. III. Chemical synthesis and characterization of n-fattyacyl mono-aminoacyl derivatives of colistin nonapeptide.

In order to examine the antimicrobial activity of n-fattyacyl mono-aminoacyl derivatives of colistin nonapeptide (CNP), twenty-one derivatives were synthesized and characterized on their chemical, physicochemical and antimicrobial properties. Five α-amino acids, glycine, l-alanine, dl-aminobutyric acid, dl-norvaline and dl-norleucine, and two ω-amino acids, β-alanine and γ-aminobutyric acid, were first acylated with each of three kinds of acid chloride, n-octanoyl, n-decanoyl and n-dodecanoyl chloride, and then esterified with p-nitrophenol prior to the coupling of those n-fattyacyl amino acids to the terminal threonine of CNP. The coupling reaction was carried out in an aqueous solvent buffered at pH 5.0 without any protection of the γ-amino groups of CNP, as reported previously.All of the derivatives obtained in hydrochloride salts were hygroscopic white amorphous powder showing decomposing points at 180~230°C. Each purified preparation exhibited a ninhydrin positive spot on a paper chromatogram, and ea...

STUDIES ON PENTENOMYCINS. I

Two new antibiotics, pentenomycins I and II have been isolated from the culture broth of Streptomyces eurythermus MCRL 0738 as a white hygroscopic amorphous powder. Pentenomycins [I: C6H8O4•1/2H2O (I), II: C8H10O5•1/2H2O (II)] are moderately active against Gram-positive and Gram-negative bacteria.

Isomerization polymerization of 2‐vinyl‐1,3‐dioxolane by α,α′‐azobisisobutyronitrile or by γ‐ray irradiation

Abstract2‐Vinyl‐1,3‐dioxolane was polymerized by use of α,α′‐azobisisobutyronitrile (AIBN) or by γ‐ray irradiation. The polymer obtained was white amorphous powder which melted at ca. 70°C. and was soluble in chloroform, acetone, and p‐dioxane. The infrared spectrum of the polymer indicated peaks at 1735 cm.−1 characteristic of the carbonyl group, and at 1200–1000 cm.−1 characteristic of the acetal group, while no absorption at 990 and 3100 cm.−1 due to the vinyl group was observed. The spectra of the polymers obtained by AIBN and by γ‐ray irradiation were essentially identical. The saponified product of the polymer was white powder and its reduced viscosity was a little larger than that of the original polymer. These results indicate that the polymer has no ester unit in the main chain. The results of gas chromatographic analysis of the saponified product of the polymer, indicate the presence of a small amount of ethyl alcohol. The results of the saponification showed that the ester content in the polymer varied from 7 to 25% depending upon the polymerization temperature. These results indicate that 2‐vinyl‐1,3‐dioxolane polymerized by AIBN or by γ‐irradiation with two modes of vinyl and hydrogen migration, yielding a copolymer having the unit structures magnified image

A New Antifungal Antibiotic, Polcillin

Polcillin was found in culture filtrate of Bacillus subtilis TPR-2201 isolated from a soil sample. By the purification it was obtained as white amorphous powder which was easily soluble in water, lower alcohol, wet acetone and pyridine. It is stable at pH values from 2.0 to 9.0. From the physicochemical studies it was found to be an acidic polypeptide consisting of such amino acids as aspartic acid, glutamic acid, serine, proline and tyrosine. The growth of fungi and yeasts are widely inhibited but most bacteria are not inhibited by above the concentration of 200 mcg/ml.

Cationic isomerization polymerization of 3,3‐dimethyl‐1‐butene

AbstractThe cationic polymerization of 3,3‐dimethyl‐1‐butene (t‐butyl ethylene) has been investigated. Polymerizations were carried out with AlCl3 catalyst in ethyl chloride solvent in the temperature range −31 to −130°C. Trimers (viscous oils or soft gels) were obtained between −31 and −100°C. The composition and structure of these materials is complicated and remains obscure. Solid polymer was obtained only at −130°C. This material, whose degree of polymerization is ∼ 68, is a white amorphous powder and it melts between 55 and 66°C. It is soluble in most common solvents.Careful NMR and IR spectroscopic studies indicate that the repeat structure of this polymer is: magnified image

ANTIBIOTIC SUBSTANCES FROM A STRAIN OF BACILLUS SUBTILIS

SUMMARY: Strain B7 of B. subtilis, isolated from soil collected from the gardens of the Bose Institute, Calcutta, was found to elaborate at least four different antibiotic substances. Fraction I was a brick red amorphous powder with certain resemblances to the bacillomycin group of antibiotics, soluble in alcohols, pyridine, etc., but insoluble in ether, water and acids. It had an ultraviolet absorption maximum at 276 mμ, melted with decomposition at 311°, and was a polypeptide positive to ninhydrin. On hydrolysis 12 amino acids were found. Fraction II was a white amorphous powder soluble in alcohols and ether but insoluble in water and petroleum ether. It melted at 158–162° and was a ninhydrin positive polypeptide composed of 7 amino acids. Fraction III was a yellow amorphous powder soluble in water and acetone, less soluble in ether and practically insoluble in chloroform. It was not a polypeptide. Fraction IV was a yellowish white amorphous powder with solubility characteristics similar to those of fractions I and II. It was a polypeptide composed of 10 amino acids.

Biochemistry of the sphingolipides. X. Phytoglycolipide, a complex phytosphingosine‐containing lipide from plant seeds

SummaryA new complex lipide, phytoglycolipide, has been isolated from soybea, corn, flaxseed, peanut, sunflowerseed, cottonseed, and wheat phosphatides. This material is obtained by a mild alkaline saponification procedure which destroys glycerol‐containing lipides. The new lipide constitutes about 5% of the crude phosphatides and is obtained as a white amorphous powder of identical composition, optical activity, and solubility properties from the various sources. Phytoglycolipide gives on hydrolysis phytosphingosine (and, in the case of soybean only, an unsaturated derivative of phytosphingosine) fatty acids, inositol, glucosamine, a hexuronic acid, galactose, arabinose, mannose, and phosphate.Phytoglycolipide is the first sphingolipide of plant origin to be described and is unique among complex sphingolipides in that it has the structural features of a glycolipide and of a phosphatide.

The gum of Fagara xanthoxyloides.

Fagara xanthoxyloides Lam. (Xanthoxylum Senegalense DC.), a common plant in West Africa, exudes a clear yellow gum during the dry season. The gum is partly acetylated and has a significant methoxyl content. A single unpurified nodule gave, on analysis, acetyl groups, 6.95 per cent; methoxyl groups, 2.6 per cent. The nodules dissolve with difficulty in water to give a viscous solution with a faintly acid reaction. The purified gum was obtained in the usual way1, and after drying in a partial vacuum at 30° was a white amorphous powder,[α]21D + 4° (c. 0.5 in N sodium hydroxide); equivalent weight by direct titration, 1,100; sulphated ash, 0.25 per cent; nitrogen, 0.23 per cent; acetyl groups, none; methoxyl groups, 2.6 per cent (a polysaccharide of equivalent weight 1,100 containing monomethyl-hexuronic residues would have a methoxyl content of 2.8 per cent). It gave a positive naphthoresorcinol test for uronic acid, and failed to reduce Fehling's solution. Specimens prepared from nodules from different trees did not show any significant differences in optical rotations and equivalent weights, indicating the essential homogeneity of the gum.

The Thermoplasticity of Thermoprene. A Study of the Adhesion of Rubber to Metal

Abstract Among chemical derivatives of rubber, there is a type to which has been given the name of isorubbers or cyclorubbers in the technical literature. Kirchhof has described at length these products, which can be prepared by various methods, e.g., by the action of heat, as described by Harries, who isolated a white amorphous powder, having a density of 0.992, by heating rubber for several hours in ether at 250–300°, under pressure, or by the action of chemical reagents, particularly sulfuric acid and inorganic and organic halogenated compounds, with which a range of products suitable for molding powders, paints, sheets, wire, etc., can be prepared. The present work is concerned, not with a further study of these products, but rather with an investigation of a particular one of these products, viz., that which is obtained by treating rubber with phenolsulfonic acid. The B. F. Goodrich Company, and Fisher in particular, have successfully developed the manufacture and use of this product, and have given it the generic and commercial name of Thermoprene. At the beginning, a large number of applications of Thermoprene were foreseen, but only one application has survived and undergone any extensive development, viz., the use of Thermoprene as an adhesive for bonding rubber to metal, a process known as the Vulcalock process. As a result of newly observed facts, it seemed of interest to take up this problem again in an attempt to improve the process in certain ways.

CLINICAL USE OF SULFAMETHYLTHIAZOLE

Since the introduction of chemotherapeutic agents effective in the treatment of streptococcic and pneumococcic infections, efforts have been made to improve on these agents and to develop a compound equally effective against infections caused by staphylococci. Sulfathiazole (2-sulfanilamidothiazole) and sulfamethylthiazole (2-sulfanilamido-4-methylthiazole) have shown promise in this direction. Sulfamethylthiazole is a white amorphous powder which is less soluble than sulfanilamide, sulfapyridine or sulfathiazole. Sulfamethylthiazole (together with sulfathiazole) was first synthesized in August 1939 by Fosbinder and Walter, 1 who also reported its effectiveness against streptococci and pneumococci. Lawrence 2 found sulfathiazole and sulfamethylthiazole to be superior to sulfanilamide in their bacteriostatic effect against Lancefield group A Streptococcus haemolyticus and against the colon-typhoid-dysentery group. Barlow and Homburger 3 reported that in experimentally produced infections with Str. haemolyticus and Pneumococcus types I, II and III the effect of thiazole derivatives of sulfanilamide was definitely superior to that of the parent substance and compared

Poisoning by Sikimitoxin

Chinese Bastard Anise, Mang T'sao, commonly known under the colloquial name T'zu Ta Liao, and identified as the fruit of Illicum religiosum, Sieb., has long been known to be poisonous. It is chiefly used as a condiment in preparing Chinese meat dishes. Fatal poisoning by these seeds is not an uncommon occurrence. The chemical nature of its toxic principle was first investigated by Eykman who, working with the Japanese anise, or sikimi-no-ki, also identified as Illicum religiosum, Sieb., isolated from the seeds a crystalline body which he named “Sikimin” and claimed for it a powerful toxic action. 12.5 mgm. of Sikimin killed a young dog in 3 hours. This crystalline body or sikimin, has never since been isolated by other workers; crude seeds, or aqueous extracts, being generally employed for the physiological study of this poisonous plant., , In a recent chemical study of Mang T'sao, the writer isolated from the seeds an amorphous poisonous principle with definite chemical and physical characters. Given to cats, 0.2 mgm. of this amorphous substance per kilogram of body weight was found to be fatal, less than 0.1 mgm. of substance per kilogram of body weight was sufficient to produce the same poisoning symptoms as those produced by the crude seeds, i. e., salivation, vomiting defecation, convulsion and death. The name “Sikimitoxin” is suggested for the new toxic principle to distinguish it from Eykman's Sikimin from which it differs in its physical and chemical properties, and also in its much higher toxicity. Properties of Sikimitoxin. It is a feebly acid nitrogen-free body and occurs as a white amorphous powder without definite melting point. When slowly heated, it sinters at 63° C., then gradually increases its volume as the temperature rises, and finally becomes a clear liquid at 135° C.

Root Action and Bacteria

IN NATURE of July 18 (p. 270) I mentioned that I had proved the excretion from plant roots of a toxic substance. This substance proves to be alkaloidal in nature, and is precipitated, in addition to the usual alkaloidal reagents, by most of the substances in use as artificial manure. Potassium sulphate and chloride appear to be the most complete precipitants of all the reagents so far tried. They appear to precipitate the substance in the form of a base—a white amorphous powder. The amount excreted is by no means negligible, and Sesamum indicum, indeed, in its early stages at least, appears to excrete more solid matter than it builds up in its own substance.