An interaction of resorcinol and caproic anhydride gave hexylylresorcinol with over 60% yield. Absense of an condensation agent, such as zinc chloride, in this reaction, results in the formation of mono- and di-esters of resorcinol. These esters, under the presence of zinc chloride, undergo Fries conversion and form the corresponding ketone compounds.
Condensation reactions between resorcinol and caproyl chloride were examined and it was concluded that the resulting product differed according to quantitative relations between the two reactants. When the amount of chloride is larger compared to resorcinol, resorcinol dicaproate is obtained whereas ketones, such as hexylresorcinols, are obtained when greater amount of resorcinol is present. However, it was assumed that even when hexylresorcinol is formed, a monocaproate of resorcinol is first formed, which, being comparatively unstable, undergoes Fries conversion by the effect of HCl present and forms the ketone.
As conditions controlling the reaction, the reaction temperature, concentration of sulfuric acid and the amount of the acid, were examined. As a result, the same conclusion as reached by Marvel and Hiers was obtained as to the temperature. The concentration of sulfuric acid seems to have the maximum effect and the most suitable was found to be around sp. d. 1.825. Considerations were given as to the action and the amount of sulfuric acid and the minimum limit necessary for the reaction was drawn. By the utilization of such knowledge, unpurified isatin of m.p. 194-5° was obtained in an yield of 94-5% of theory which is better than the results obtained heretofore.
Electric dialyzer was used for the purification of iodo-casein by which elimination of inorganic iodine was effected with high efficiency. Dialysis heretofore used has not been able to give products with less than 0.2% iodine but its content was brought down to 0.02-0.03% by the electric dialysis. In physiological tests using tadpoles, it was found that the physiological effects of iodo-casein has remarkably been advanced in these products and any harmful or toxic properties have been eliminated. Good results were obtained by the use of ammeter as indicator of the process of dialysis. Products with 6.2% organic iodine was obtained at 0.45amp., 5.8% I at 0.4amp., 5.2% I at 0.35amp., and 4.6% I at 0.3amp. The amount of organic iodine contained in the product was proportional to the amount of electricity passed so that this method will allow constant products to be obtained from a certain material as well as those containing optional amount of iodine.
Symmetric branched-chain fatty acids, i.e., possessing same side chains, were synthesized and the relationship between their structures and their antibacterial power against Staphylococcus aureus was examined. It was shown that, rather than the distance of branching point of the side chain from the carboxyl radical, the total number of the C-atoms in the acid, in the range of 16-17, was responsible for the strength of antibacterial properties. It was again determined that the melting point of compounds decreased as the distance of the side-chain from the carboxyl increased.
Seven kinds of fatty acids possessing branched-chain in the α-or β-positions of the carboxyl radical were given to rabbits and specific rotations were measured and compared of the monocarboxylic acids, eliminated without change, and dicarboxylic acids elimihated after ω-oxidation. In either case, values were not very great and all were dextrorotatory. No evidence was obtained as to the assumption that biological oxidation, especially the ω-oxidation, was assymmetric.
L. F. Fieser et al. in 1940, synthesized four kinds of quinonyl fatty acid, i.e. γ-quinonyl (or naphthoquinonyl)-butyric acid and ε-quinonyl (or naphthoquinonyl)-caproic acid, in order to examine their biological reactions. The authors, also with the same purpose in mind, synthesized five kinds of β-alkyl-γ-quinonylpropionic acids, in which alkyl were H, CH3, C2H5, iso-C5H11 and C12H25. The first three compounds were obtained by chromic acid oxidation of anisidine compounds but the last two, by going through hydroquinone compounds. In each cases the hydroquinone compounds were obtained as their lactones, which turned into respective quinones by boiling with a large excess of ferric chloride solution.
The structure of convolvulinolic acid, the aglycone of convolvulin, the glycoside of Jalap resin, was synthetically denied by Davies and Adams as to 11-hydroxypentadecanoic acid proposed by Asahina and Akasu. Since the melting point of convolvulinolic acid and that of 3-desoxyipurolic acid were the same, and their mixed fusion gave no depression of the melting point, the author derived keto acid, semicarbazone and dl-hydroxy acid from both convolvulinolic and 3-desoxyipurolic acid. On the other hand, the same derivatives of 11-hydroxypentadecanoic and 11-hydroxymyristic acids were also synthesized by means different from that of Davies and Adams. By comparison and mixed fusion of these derivatives, it was found that convolvulinolic and 3-desoxyipurolic acids were identical, both being 11-hydroxymyristic acid. By the same method, jalap inolic acid, obtained from Scammony resin, was synthetically proved to be 11-hydroxypalmitic acid.
N-nitroso-p-toluenesulfomethylamide and N-nitroso-p-toluenesulfobenzylamide were synthesized and the behavior of their N-nitroso radical was studied. The reaction with hydrocarbons give, not nitroso compounds, but esters of p-toluenesulfonic acid by liberation of nitrogen in thermal decomposition, and, in the case of benzyl compound, formation of benzaldehyde as well. This reaction is similar to decomposition of N-nitrosoacetanilide and can well be explained by the reaction mechanism proposed for it. N-nitrososulfonamide also undergoes nitrosation reaction at temperatures below its decomposition point, e. g. forming N-nitrosodiphenylamine from diphenylamine.
In general, electrolysis of a solution obtained by the hydrolysis of polysaccharides with acid, placed in the cathode chamber of a diaphragm electrolytic cell, allowing acid ions to tranber quantitatively into the anode chamber, acids can be recovered, if sulfuric or nitric acids are used, as anolyte, and monosaccharides of high purity can be obtained from the neutral sugar solution as catholyte. A new process of preparing monosaccharides, designated as the electrolytic preparation of sugars, combines this process of acid saccharification of polysaccharides and an electrolytic process of neutralization. Fundamental studies of this process were carried out in order to determine its feasibility and following points were made clear. 1) The amount of acid in acid saccharification solution decreases in direct linear proportion to the amount of current passed and is removed quantitatively. In the case of sulfuric and nitric acids, these acids are recovered almost quantitatively. 2) The dissolved monosaccharides (glucose, xylose, fructose) are not electrolytically reduced. 3) Any acids that are suitable for saccharification and have a large transport number can be used in this process. 4) Glucose of high purity can be obtained in a very high yield by the electrolytic deacidification of saccharification solution obtained by treating starch with sulfuric acid at a room temperature.
Fundamental studies on the electrolytic preparation of sugars were carried out and following results were obtained: 1) Sulfuric acid recovered by this method of electrolysis can be used repeatedly. The most suitable concentration of sulfuric acid for the anolyte is between 5% and 10%. The removal of SO4-- is not complete above 30% concentration. 2) Following effects could be numerically presented at the same time. It became possible to present following effects numerically which could not be done by the neutralization method, these being effected concurrently with electrolytic deacidification and acid recovery: a) Heavy metals, such as Fe, Cu, Pb, are quantitatively removed; b) the saccharification solution is decolorized and purified to about 1/5 of the original; and c) the ash content becomes smaller than that of the original. Fundamental factors necessary for the practical use of the electrolytic preparation of sugars were thus obtained.
Electrolytic preparation of pure glucose from starch was attempted in accordance with the results obtained by its fundamental studies. A pure starch was saccharified by 2% solution of sulfuric acid by boiling at ordinary pressure until the degree of rotation and reduction value of the saccharified solution became constant. This solution was then placed in the cathode chamber of a diaphragm electrolytic cell of lead and electrolyzed in the usual manner. This pale and clear, neutral sugar solution was decolorized, condensed and allowed to solidify. This crystalline mass was found to meet all the tests, except of moisture, required by the Japanese Pharmacopoeae. The yield was 95% of theoretical amount as calculated from starch. Anhydrous glucose allowed to crystallize from decolorized and condensed electrolytic deacidified solution by the addition of methanol was found to conform in all respects to that specified in the Japanese Pharmacopoeae with an yield of 70% crystallization. Calculated from crude starch, this was an yield of 54-67% of theoretical amount. This is the first example of glucose being obtained in such high purity and in so good an yield which goes to show the overall characteristics of this process.
As an application of the electrolytic preparation of sugars to that other than glucose, preparation of xylose from corn (maze) stalk, and of crystalline fructose from crude inulin of dahlia, were carried out. Instead of isolating xylan from corn stalks, this was directly saccharified at an ordinary pressure and the saccharified solution electrolyzed in the usual manner. With the purification and removal of iron and color, dissolved furfural disappeared, and a neutral sugar solution of high purity was obtained. This solution was decolorized, condensed under reduced pressure, and the syrup herewith obtained solidified to a crystalline mass giving an m.p. of 108-117°. Yield, 14%. By recrystallization, products of m.p. 141-5°, [α]D10=+19.4 was obtained in a 6.5% yield. Crude inulin from dahlia bulb was treated in the same manner and fructose crystallized from its syrup. By treating this crystalline mass with methanol, crystalline fructose was obtained in a 41% yield, giving m.p. 91-5°, [α]D18=-92.7. Recrystallization gave pure product of m.p. 96-101°, [α]D16=-93.0. Yield, 35%. Comparison of the ash content and color of sugar solution obtained by the neutralization method with those of the neutral sugar solution by the present process and those of the original saccharified solution showed the neutral sugar solution obtained by the present method to posses far smaller amount of ash with less color. These have been numerically presented.
Having succeeded in obtained glucose, xylose and fructose of high purity in good yields by the electrolytic process, its industrialization was planned and experiments on a semi-industrial scale were carried out. As a result, automatic, continuous neutralization of starch saccharified solution was successfully carried out thereby confirming the possibility of practical industrial application of this process for the manufacture of monosaccharides. Points noted in the industrial application of this process were as follows: 1) In order to make automatic, continuous neutralization of acid saccharified solution, flow type electrolysis was used in a following manner: a) In order to allow electric wiring so as to correspond to individual resistance of cells connected in series and placed on different levels, a suitable number of electrolytic cells lined in series is taken as one group and these groups are connected in parallel. By such combination of electrolysis in series and in parallel, capacity of each cell is approximately equalized. b) A special electrolytic cell was designed so as to cope with excessive effervescence of saccharified solution (catholyte). However, in actual practice, the effervescence was not strong enough to necessitate the use of such special cells 2) Iron is almost quantitatively removed at the time of electrolytic deacidification. 3) It goes without saying that the electrolytic removal of SO4-- is completely quantitative. 4) The yield on sugars was 96-99% and the loss was very small. As can be seen from these results, the experimental application on semi-industrial scale was more than equal to that of laboratory scale.
By the hydrogenation of carbonyl compounds, in the presence of an amide at high temperature and high pressure over nickel catalysts, corresponding acylamino derivatives were obtained. As the carbonyl compounds, acetone, phenylacetone, acetophenone, benzaldehyde and p-sulfonamidobenzaldehyde were employed, with formamide, formylmethylamide and acetamide as the amides.
By the hydrogenation of nitriles in the presence of amide or esters of formic acid, at high temperature and high pressure over nickel catalysts, formylamino derivatives were obtained with good yields. In general, the yield of primary amines obtained by the hydrogenation of nitriles is very poor due to formation of secondary amine, but by the present method, the side reaction is inhibited strongly and the yield of formylated primary amines show an increase of over 30% compared to the ordinary catalytic reduction. The nitriles used were benzonitrile, benzyl cyanide, acetnitrile, propionitrile, p-sulfonamidobenzonitrile, 2-methyl-4-amino-5-cyanopyrimidine, ethylenecyanohydrin, methyl cyanoacetate, ethyl cyanoacetate and cyanoacetamide.