(Methylenedithio) diacetic acid derivatives were prepared and were submitted to tests for antibacterial and antiprotozoal activity in order to examine the relationship between biological action and chemical structure. These derivatives in general were found to be effective against Trichomonas sp.
A total of 92 kinds of compounds selected from 3-methyl-5-pyrazolone, antipyrine, thiopyrine, phthalazine, and quinazoline series, whose effect against human tubercle bacilli had not been tested, were submitted to in vitro tests. 4-Hydrazinoquinazoline was found to inhibit growth in a concentration of 6.25γ/cc., while others showed no observable effect. Thirteen kinds of 4-hydrazinoquinazoline derivative were newly synthesized and their growth inhibitory action was tested with human type tubercle bacilli.
Aqueous solution of ammonium carbonate, sodium carbonate, ammonia water, or sodium hydroxide was added to the aqueous solution of cadmium nitrate (tetrahydrate) and cadmium carbonate or hydroxide so formed was submitted to pyrolysis. With the four kinds of cadmium oxide (CdO (I), (II), (III), (IV)) thereby obtained, bulk density, surface area, and reduction velocity with hydrogen were examined, and the oxide was used as a catalyst in the catalytic vapor-phase decomposition of isopropyl alcohol. It was thereby found that CdO (I), obtained by the pyrolysis of cadmium carbonate prepared with ammonium carbonate as the precipitation agent, had the largest surface area, was the most active in reduction with hydrogen, and dehydrogenation of the alcohol was the most efficient. On the other hand, CdO (IV), obtained by pyrolysis of cadmium hydroxide prepared with sodium hydroxide as the precipitation agent, had the smallest surface area, was consequently most inactive in reduction with hydrogen, and dehydrogenation ability of the alcohol was the smallest.
In order to study the mechanism of biosynthesis of santonin, Artemisia maritima L. was cultivated hydroponically with aeration and effect on growth and santonin formation of various elements were examined. Hydroponic culture was carried out for three generations from 1956 to 1957 and the effect of 10% decrease in potassium, calcium, nitrogen, phosphoric acid (as P2O5), magnesium, and sulfur in the hydroponic culture solution, and various concentrations of the Houghland solution were tested.
Crude drugs and plants, numbering 229 kinds, were examined for principles having uterus contracting action and it was found that an extract of Lespedeza bicolor var. iaponica NAKAI (family Leguminosae) showed a comparatively strong action. From the result of various tests, the active principle of this plant was assumed to be an alkaloid and the principle was extracted y the usual method, affording white prisms melting at 47-48°. A molecular formula of C12H16N2 was given for this substance from elemental analyticalvalues and molecular weight determination. There has been no report of identification of this kind of a substance fro the Lespedeza sp. and the substance was tentatively named alkaloid L. Ultraviolet absorption spectrum and various tests indicated the alkaloid L to possess an indole ring and a side chain of dimethylaminoethyl group was assumed to be attached to its 3-position. The alkaloid L was therefore derived to its methiodide and it was found that this methiodide was identical with N, N-dimethyltryptamine methiodide in respect to its melting point, elemental analyses, and infrared absorption spctrum. Therefore, the alkaloid L would be N, N-dimethyltryptamine. A dose of 50mγ/cc. of this alkaloid contracted excised uterus of a hamster. The effect of N, N-dimethyltryptamine on the tryptophan demand of Lactobacillus arabinosus, with tryptophan as the essential growth factor, was examined by microbiological assay but no effect was found to be exerted on fungal growth.
Quaternary salt of 4-picoline was condensed with aromatic aldehydes by the usual method to form 13 kinds of styryl-type dyes and was fused with formamidines to give seven kinds of aminovinyl-type dyes. Styryl-type dyes were also obtained by the reaction of pyridine-2- and -3-aldehydes respectively with 1-ethyl-4-picolinium iodide, 1-methylquinaldinium iodide, and 2, 3, 4-trimethylthiazolium iodide, and the dyes were converted to their haloalkyl derivatives. The majority of these dyes were submitted to antimicrobial tests with dehydroacetic acid and sorbic acid as the control.
Cyanothiamine was submitted to decomposition with hydrochloric acid, 4-methyl-5- (2-hydroxyethyl) -4-thiazolin-2-one, secondarily formed by the action of the acid on 3-thiocyano-5-hydroxypentan-2-one, one of the decomposition products of the foregoing reaction, was separated, and the structure of cyanothiamine was reconfirmed. The substance of m.p. 215° (decomp.), separated during the decomposition of cyanothiamine with hydrochloric acid, afforded thiochrome in an extremely good yield by the application of water or weak acid. It was found to give 2-imino-3-[(2-methyl-4-amino-5-pyrimidinyl) methyl]-4-methyl-5-(2-hydroxyethyl) thiazole on the application of a strong acid. Further, chemical properties and ultraviolet absorption spectra were examined, and the structure of this substance was concluded as 2-imino-3-[(2-methyl-4-amino-5-pyrimidinyl) methyl]-3a-methyl-3a, 5, 6, 6a-tetrahydrofuro [2, 3-d] thiazole.
Various isonicotinic acid hydrazide derivatives were prepared and their nitrous acid-consumption was measured (cf. Table I). The compounds with more than one hydrogen atom in N2-position and without any acyl group consumed 1 mole of nitrous acid while those with one acyl group or two alkyl groups in N2 did not consume any acid. The disodium isonicotinic acid hydrazide-bis (methanesulfonate) (III), reported by Obika, Tsuno-o, and Sasahara, and by Logemann, De Franceschi, and Zamboni, was prepared but (III) did not consume nitrous acid at all. Therefore, it may be assumed that the structure of (III) is 1-isonicotinoyl-2, 2-bis (sodiosulfo-methyl) hydrazine (IIIb).
As a part of work on the synthesis of chemotherapeutics, diaryl sulfones were prepared. Compounds of bis (4-aminophenyl) sulfone system included bis (4-nicotinamidophenyl), bis [4-(2-hydroxy-1-naphthylazo) phenyl], bis (2-aminobenzothiazol-6-yl), bis (4-maleylamidophenyl), bis (4-succinylamidophenyl), and bis (4-phthalylamidophenyl) sulfones. Those of bis [4-hydrazinophenyl) sulfone series included bis (4-furfurylidenehydrazinophenyl), bis [4-(3-methoxy-4-hydroxybenzylidenehydrazino) phenyl], bis [4-piperonylidenehydrazinophenyl], bis (4-cinnamylidenehydrazinophenyl), and bis [4-(4-dimethylaminobenzylidenehydrazino) phenyl] sulfones. 2-Lepidyl 4-nitrophenyl sulfone and bis (2-hydroxy-3, 5-dichlorophenyl) sulfoxide were also prepared. This latter was assumed to have been formed by the steric hindrance of hydroxyl group in the ortho position, oxidation to the sulfone not having been effected.
For the purpose of preparing cycleanine (I), an attempt was made to cyclize the Schiff base (VII) by the Pomeranz-Fritsch reaction to 1-(4-bromobenzyl)-6, 7-dimethoxy-8-hydroxyisoquinoline (VIII) but instead of the anticipated substance (VIII), 6, 7-dimethoxy-8-hydroxyisoquinoline (IX) was obtained, formed by the liberation of the p-bromobenzyl group. The structure of (IX) was confirmed by the formation of anhalidine (2-methyl-6, 7-dimethoxy-8-hydroxy-1, 2, 3, 4-tetrahydroisoquinoline) (XI) by reduction of its methiodide (X) with tin and hydrochloric acid. In connection with the foregoing, it was found that the Bischler-Napieralski reaction starting with N-formyl-3, 4-dimethoxy-5-benzyloxyphenethylamine (XIX) gave 6-benzyloxy-7, 8-dimethoxy-3, 4-dihydroisoquinoline (XX), and that the reduction and debenzylation of its methiodide (XXI) afforded 2-methyl-6-hydroxy-7, 8-dimethoxy-1, 2, 3, 4-tetrahydroisoquinoline (XXIII), an isomer of (XI).
A total of 73 kinds of compounds, including 11 derivatives of alkylcoumarin, 2 of 2-thiocoumarin, 3 of oxocoumarin, 4 of 6-nitrocoumarin, 14 of aminocoumarin, 9 of hydroxycoumarin, 9 of carboxylic acid, 9 of naphthopyrone, and 12 of coumarin homologs were prepared and their structure-activity relationship was examined by screening the activity of body temperature depression with albino rats. In general, almost all coumarin derivatives showed the activity and coumarin itself had a comparatively strong effect. In methylcoumarin derivatives, the effect was generally stronger when the methyl group was in the α-pyrone ring than in the benzene ring. In 3-alkylcoumarin derivatives, methyl and propyl derivatives had strong activity, while ethyl and butyl derivatives had weaker action. Saturation of the double bond in 3-4 position in coumarin and 4-methylcoumarin with hydrogen decreased the effect, the change of the ketone group in 2-position to thione group failed to show any change in effect, and introduction of a nitro or amino group in 6-position decreased the effect, the amino group being affected less. However, its acetylated or benzoylated compounds had only a weak effect. In general, derivation of the amino group to its hydrochloride increased the effect. Introduction of a carboxyl in the 3-position increased toxicity, while this group in 4- or 6-position decreased both the toxicity and effect. Oxocoumarin, hydroxycoumarin, and naphthopyrone derivatives had only a weak effect. The change of α-pyrone to γ-pyrone ring to form chromone left majority of the effect intact but the effect was very weak in isocoumarincarboxylic acid derivatives, coumarinic acid, phthalide, coumarone, 2-acetylcoumarone, coumarane, coumalinic acid, chelidonic acid, and diethyl chelidonate.
Oxidation of 10-thiaxanthenylacetic acid with hydrogen peroxide in glacial acetic acid afforded 10-thiaxanthenylacetic acid 5, 5-dioxide (IV). 10-Thiaxanthenylcyanoacetic acid 5, 5-dioxide, obtained by similar oxidation of 10-thiaxanthenylcyanoacetic acid, also afforded (IV) via 10-thiaxanthenylacetonitrile 5, 5-dioxide. 10-Thiaxanthenol 5, 5-dioxide did not undergo condensation with malonic acid in glacial acetic acid. Seven kinds of alkamine ester of (IV) were prepared and their toxicity, antiacetylcholine, antihistamine, and antibarium chloride actions were comparatively examined. These esters, especially 2-dimethylaminoisopropyl ester, were found to have stronger antihistamine and antibarium chloride actions than the esters of 9-xanthenylacetic and 10-thiaxanthenylacetic acids.
Amine derivatives of sugars and polyhydric alcohols were prepared and their utility as the protective coating agent was examined. The amine derivatives of sugars were prepared either by refluxing glucose, xylose, or lactose with various amines in alcohol or by the application of various amines to sucrose, dextrin, and mannitol p-toluenesulfonates. Of these various amine derivatives, dodecylamine N-lactoside and N-xyloside were the only ones that possessed resistance to water, solubility in gastric juice, and ability to form a membrane. These were used as a coating on starch-lactose tablets and their resistance to water and solubility in gastric juice were tested by measuring the duration of disintegration in distilled water and simulated gastric fluid. Both derivatives were found to be excellent agent for a protective coating.
Following acetylenic alcohols were oxidized with manganese dioxide and corresponding acetylenic ketones were formed without affecting the triple bond. The alcohols used were 1-phenyl-2-propyn-1-ol, 1, 4-diphenyl-3-butyn-2-ol, 1-hexyn-3-ol, 1-phenyl-2, 4-heptadiyn-1-ol, 1-(2-hydroxyphenyl)-2, 4-hexadiyn-1-ol, 1-(1-naphthyl)-2, 4-hexadiyn-1-ol, 1-(3-methoxy-4-hydroxyphenyl)-2, 4-hexadiyn-1-ol, 1, 6-di (1-naphthyl)-2, 4-hexadiyne-1, 6-diol (two isomers of m.p. 182° and 169°), and 1, 6-diphenyl-2, 4-hexadiyne-1, 6-diol (two isomers of m.p. 135° and 113°).
In order to examine the relationship between chemical structure and its atropine-and papaverine-like actions, derivatives of 1, 1-diphenyl-3-aminobutanol, 1, 1-diphenyl-3-aminobutene, and diphenylpyridylmethanol were prepared.
Paper electrophoresis was carried out with the extract of the root of Indian snakewood (Rauwolfia serpentina BENTH.) with N acetic acid and 0.1N citric acid as the electrolytic solution. And nine kinds of alkaloid, serpentinine, ajmaline, yohimbine (?), sarpagine, ajmalicine, serpentine, reserpinine, reserpine, and rescinnamine, were isolated. The same extract was submitted to multi-buffered paper chromatography, using filter papers impregnated in equidistances with citrate buffers of pH 6.4, 6.1, 5.8, 5.5, 5.2, 4.9, 4.6, 4.3, 4.0, 3.0, and 2.1 in that order and using chloroform-benzene (1: 2) mixture as the developing solvent. In this case, eight spots of alkaloids were obtained, reserpine at pH 3.0, ajmalicine at pH 4.0, rescinnamine at 4.3-4.6, reserpine at 4.6, yohimbine at 5.5, methyl reserpate (?) at 6.1, ajmaline at 6.1-6.4, and serpentinine at 6.4-0, while serpentine and sarpagine remained in the original spot.
The Formosan cobra venom was purified by fractional precipitation with acetone, ammonium sulfate, and ethanol, and a homogeneous substance, assumed to be lecithinase, was obtained. Its minimum lethal dose in mouse was 12-13γ/g. and its lecithinase action was approx. 16 times that of the crude venom. Its molecular weight was calculated as 28, 500 (osmotic pressure method). Aspartic acid was detected as the N-terminal amino acid and aspartic acid, glutamic acid, and glycine as the C-terminal acid. C terminal aspartic and glutamic acids are present as asparagine and glutamine, and the carboxyl group in the β-position in the N-terminal aspartic acid is thought to be present as an amide form or in peptide bonding. From the result of determination of these terminal amino acids, the peptide chain constituting the leci thinase is assumed to bebranched. The composite amino acids of the lecithinase are shown in Table III from which it can be seen that all the nitrogen in the lecithinase are only from these amino acids. Since the lecithinase gives a weak positive Molish reaction, presence of a sugar component can be assumed but the amount must be very small since the lecithinase is composed almost entirely of these amino acids. Comparison of these results with the properties of crotoxin obtained by Fraenkel-Conrat and others indicate difference in the terminal amino acids and amino acid composition and, therefore, the lecithinase-active substance in crotoxin must have a different structure from the lecithinase in Formosan cobra venom.
Extraction of fresh leaves of Juglans regia L. var. sinensis C. DC. with methanol and treatment of the methanol extract with lead acetate afforded pale yellow scales, m.p. 224-225°, [α]23D: -169°, C20H18O10⋅1 1/2H2O, in 0.1% yield. This substance was named juglanin. Hydrolysis of juglanin with 5% sulfuric acid gave 1 mole each of kaempferol and arabinose, and permethylation with diazomethane followed by hydrolysis afforded 5, 7, 4′-tri-O-methyl-kaempferol. It follows, therefore, that the sugar is bonded to the 3-position and juglanin is kaempferol 3-arabinoside.
D-Xylose was derived to acetobromo-D-xylose, which was condensed with various aliphatic alcohols in chloroform by the König-Knorr reaction, and 10 kinds of alkyl 2, 3, 4-tri-O-acetyl-β-D-xylopyranoside were newly prepared. Butyl compound, m.p. 101.5-102.0°; pentyl, m.p. 55.0-56.5°; hexyl, syrup; octyl, syrup; decyl, m.p. 50-51°; dodecyl, m.p. 59.5-61.0°, tetradecyl, m.p. 67.5-68.5°; hexadecyl, m.p. 74-75°; octadecyl, m.p. 79-80°; cis-9-octadecenyl, b.p0.1 209°. These xylopyranosides were deacetylated with 0.001N sodium methoxide to alkyl β-D-xylopyranosides. Butyl compound, m.p. 90.0-91.5°, or m.p. 57-58° with 1 mole of water of crystallization; pentyl, m.p. 90.0-91.5°, or m.p. 58-59° with 1 mole of water of crystallization; hexyl, m.p. 90-91°; octyl, syrup; decyl, m.p. 98.5-99.5°; dodecyl, m.p. 101.5-102°; tetradecyl, m.p. 103-104°; hexadecyl, m.p. 105.5-107.0°; octadecyl, m.p. 107-108°; cis-9-octadecenyl, syrup. Of these, purification of pentyl, octyl, and cis-9-octadecenyl β-D-xylopyranosides was difficult by the usual method that they were separated and purified through column chromatography.
Structure of the triterpenoid, jegosapogenol, forming the parent structure of jegosaponin, the saponin contained in the fruit rind of Styrax japonica SIEB. ET ZUCC., was examined. Jegosapogenol, C30H50O5, possesses a double bond, -CH=C<, and five primary or secondary hydroxyls, four of which are two pairs in adjacent positions, such as 1-2 or 1-3 positions, and the remainder is an inactive hydroxyl. Selenium dehydrogenation of jegosapogenol afforded 1, 2, 3, 4-tetramethylbenzene, 2, 7-dimethyl-naphthalene, 1, 2, 7-trimethylnaphthalene, and a product assumed to be a picene derivative of high melting point. It was thereby assumed that jegosapogenol Would be a pentacyclic triterpenoid of the α- or β-amyrin system.
The structure of jegosapogenol was approximately assumed as (I) from the result of its oxidation with three kinds of oxidation agent. Oxidation of tetraacetyljego-sapogenol with selenium dioxide afforded tetraacetylanhydrojegosapogenol (saponified product, C30H48O4) whose ultraviolet absorption spectrum suggested the presence of β-amyrin ring with axial hydroxyl at 19-position. Properties of the hydroxyls were examined by chromium trioxide and Criegee oxidation and the presence of 1, 2 and 1, 3-diols was confirmed.
Examinations were made on the saponin, japoaescin, contained in the fruit of Aesculus turbinata BLUME, and its components. It was found that japoaescin is formed with a triterpene alcohol of m.p. 293-294°, [α]D=-11.6°, C30H50O6, as the parent structure, with xylose, glucose, glucuronic acid, and tiglic acid bonded to it in the following manner: C58H90O28+5H2O=C30H50O6+C5H10O5+C6H12C6+2C6H10O7+C5H8O2 Japoaescin Japoaescigenol Xylose Glucose Glucuronic Tiglic acid acid.
Structure of the japoaescigenol, forming the parent structure of japoaescin, a saponin contained in the fruit of Aesculus turbinata BLUME, was examined, and it was assumed that japoaescigenol would be a triterpene alcohol with five hydroxyls, -CH=C<, and an ether linkage. It was found that four of five hydroxyls are two pairs in adjacent positions, the one pair being at 1-2 positions and the other at 1-3 positions. Japoaescigenol has one more hydroxyl than aescigenin whose structure has been proposed by L. Ruzicka and there is difference between their attitudes of ether-linkage.
From the air-dried pericarps of Ruta graveolens L., a trace of phenolic and nonphenolic weak bases (0.07%) were isolated by succesive extraction with petroleum ether and methanol, and subsequent treatment in the usual manner. The colorless needle crystals, m.p. 169-170° (picrate: m.p. 217-218°), obtained from the non-phenolic bases by crystallization from hydrated ethanol, were found to be identical with those of kokusaginine. The pale yellow prismatic crystals, m.p. 176° (picrate: m.p. 195-197°), obtained in 0.0018% yield from the foregoing crystallization mother liquor by chromatography on alumina in benzene solution, were proved to be those of skimmianine.
During the course of isolation of an effective component from Ligusticum acutilobum SIEB. et ZUCC., a phytosterol was obtained. Its melting point, optical rotation, analytical values, and chemical properties agreed with those of β-sitosterol and their identity was confirmed by direct comparison with an authentic specimen.
Several kinds of alkaloid are present in the leaves of Neolitsea serica (BLUME) KOIDZ., a domestic plant of the Lauraceae family, and one of its non-phenolic bases was proved to be l-roemerine by its Hofmann degradation and infrared spectral measurement.
Cleavage reaction of isotetrandrine dimethiodide (VI), a quaternary base of the biscoclaurine type, with liquid ammonia and sodium was examined. As a result, N, N-dimethylcoclaurine hydromethine (VII) was identified as the phenolic base. The nonphenolic base was examined by paper chromatography and it was found to be a mixture of several decomposed bases, which could not be isolated into each unity. From the Rf values, however, the presence of N, O-dimethylarmepavine hydromethine (V) was assumed. It follows that in this reaction, Emde decomposition occurs besides the ordinary cleavage of the ether oxygen forming the diphenyl ether linkage and the base is decomposed to the methyl hydromethine stage.
Phenyl esters of o-, m-, and p-fluorobenzoic acid and 3-methyl-4-fluorobenzoic acid were prepared and fluorine-containing N-sulfanilylbenzamides were derived from these by the fusion of a mixture of 2 moles of these phenyl esters, 2 moles of sulfanil-amide, and 1-2 moles of anhydrous potassium carbonate. All these fluorine-containing phenyl esters and N-sulfanilylbenzamide derivatives are yet unknown in literature.
Benzaldehyde phenylhydrazone and acetaldehyde phenylhydrazone reacted with formamide when they were heated to form chiefly 1-phenyl-1, 2, 4-triazole and the corresponding N-alkylformamide The reaction of benzaldehyde azine and formamide afforded 1, 2, 4-triazole and N-benzylformamide. In these reactions, it appears that an intermediate of hydrazine or formylhydrazine is formed during the course of triazole formation and cleavage reaction occurs at the =C=N- bond with reductive condensation.
Derivatives of 2-aminoketone, 1-substituted 3-aminopropanol, and 1, 1-diphenyl-3-aminobutane were synthesized for the purpose of examining chemical structure and physicochemical properties required for the appearance of atropine-, papaverine-and acetylcholine-like actions.
Yellow needle crystals, m.p. 118.5°, were obtained in 0.25% yield from the root of Eupatrium japonicum THUNB. This substance indicated bright green coloration with ferric chloride, negative flavone and Fehling reactions. It possesses a conjugated double bond and a carbonyl group, and isopropenyl group was found from its infrared spectrum. Its properties agreed entirely with those of euparin and they were assumed to be identical, although no direct comparison was made.
Extraction of the fresh leaves of Cornus controversa HEMSL and of Ailanthtus altissima SWINGL with methanol afforded pale yellow microneedles, m.p. 225-226° and m.p. 230°, respectively in 0.4% and 0.2% yield. The two were found to be one and the same isoquercitrin (quercetin 3-glucoside). Pale yellow microneedles, m.p. 180-181°, were obtained in 0.2% yield from the leaves of Ricinus communis L. and the substance was proved to be rutin.
Twelve kinds of hydrazone were prepared by the application of p-aminosalicylic acid hydrazide to 12 kinds of aldehydes and ketones including orsellinaldehyde, β-orsellinaldehyde, 5-ethyl-2, 4-dihydroxybenzaldehyde, 3-chloro-2, 4-dihydroxy-5-amylbenzaldehyde, methyl isohaemmatomate, and usnic acid. A total of 44 kinds of compounds including these and other known substances were submitted to in vitro tests against tubercle bacilli H37Rv but none had greater activity of inhibiting growth than PAS at 0.156-0.625γ/cc. None of the compounds tested showed any specific antibacterial action against PAS-resistant strains. Growth inhibition was observed with 0.313γ/cc. of p-aminosalicyloylhydrazones of ethyl acetoacetate, salicylideneacetone, and p-dimethyl aminobenzaldehyde, and with 0.63γ/cc. of p-aminosalicyloylhydrazones of ethyl methyl ketone and anisaldehyde.
Determination of calcium content in the casein coagulated by rennet or pepsin indicated that the amount of calcium bonded increases in proportion to pH when the application of the two enzymes to milk is made within the range of isoelectric point of casein to pH 7.0, with smaller content in milk serum. In the milk of same pH, coagulation time changes with the strength of enzyme activity but the content of calcium in coagulated casein remains constant. Calcium in coagulated casein dissolves out reversibly by acidification and there is no great variation of pH in the course of milk coagulation by the two enzymes. Ultraviolet absorption spectra of coagulated casein by the two enzymes and that of natural casein were measured. There was no difference among the three at pH 2.0 but at pH 11.0, the absorption band of the coagulated casein at around 276-290mμ was different from that of natural casein.
Specific gravity and dielectric constant of polyethylene glycol and allied substances were measured. The specific gravity of a mixture of polyethylene glycol and water, and of glycerol and water increases with increasing concentration (Fig. 2), and the maximum value of specific gravity of polyethylene glycol-water system was at 60-70% concentration (Fig. 1). It is therefore assumed that the mixture of polyethylene glycol and water is in strongest association in this concentration range. Measurement of dielectric constant was made by the phase compensation method, using the cell shown in Fig. 4. By plotting the dielectric constant against concentration, the curve shown in Fig. 3. was obtained. The dielectric constant-concentration curve was almost straight for the polyethylene glycol 400-water and of glycerol-water mixtures, indicating that association is unlikely in these cases. A specific curve was seen in polyethylene glycol-water mixture in the range of 50-90% concentration. From this fact, polyethylene glycol-water mixture is in association at 50-90% concentration and it becomes the maximum at around 60%.