The fact that the ribonucleic acid regenerated from its silver complex is of higher purity than that of commercial yeast nucleic acid preparation suggests the possibility of the use of this process for purification of ribonucleic acid preparations. The commercial preparation of sodium yeast-ribonucleate was found by ninhydrin reaction tests to be contaminated with a fair amount of proteinic substances. Therefore, such a commercial preparation was submitted to comparative tests of deproteinization by purification through silver-ribonucleic acid complex formation and by Sevag's chloroform gel method. The former was found to be highly effective, the deproteinization effect obtained finally by nine repetition of the chloroform gel process being attained in one purification through the silver-ribonucleic acid complex. It was assumed that the deproteinization of this purification through the silver complex is effected by colloidal absorption of occluded impurities by the silver sulfide formed. Therefore, copper nitrate or nickel nitrate and hydrogen sulfide can also effect purification of nucleic acid but the yield in such a case is only around 20-40% against that of 80-90% by the silver complex method. Further, the purification process becomes more complicated by the use of copper or nickel salts.
A monocyclic, saturated hydrocarbon, C10H20, was isolated from the flowers of Osmanthus fragrans LOUR. var. aurantiacus MAKINO and it was named osmane. On the other hand, this substance was synthesized from α-thujone and the structure of osmane was established as 1, 2-dimethyl-3-isopropylcyclopentane. Palmitic and stearic acids, and a minute quantity of acetic acid were detected as the component of this flower.
Planer structure of α-kainic acid and α-allokainic acid, the active components of Digenea simplex AG., has already been determined as 2-carboxy-4-isopropenyl-3-pyrrolidinoacetic acid. As preliminary experiments to the synthesis of this substance, Dieckmann reaction of N-ethoxycarbonyl-N-(2-ethoxycarbonylethyl) glycine ethyl ester (III) was attempted. The structural examination of the reaction product revealed it to be diethyl 4-oxo-1, 3-pyrrolidinedicarboxylate (IV) and not 1, 2-dicarboxylate (IV′) which is also a possibility. A new, dibasic amino acid, 4-carboxy-3-pyrrolidineacetic acid (X) was prepared from (IV) through the hydroxy (V) and the pyrroline compound (VI), and diethyl 1, 4-diethoxycarbonyl-3-pyrrolidinemalonate (IX).
It was assumed that the substitution of one of the methylene group in N-ethoxycarbonyl-N-(2-ethoxycarbonylethyl) glycine ethyl ester with an isopropyl group would effect cyclization in a reverse direction to the one reported in the preceding paper on the Dieckmann reaction. Therefore, this reaction was carried out on N-ethoxycarbonyl-N-(2-ethoxycarbonyl-3-methylbutyl) glycine ethyl ester (IV) and diethyl 3-oxo-4-isopropyl-1, 2-pyrrolidinedicarboxylate (V) was obtained as anticipated. The structure of (V) was established by the fact that the same substance is obtained by the Dieckmann reaction of ethyl 2-(N-cyanomethyl-N-ethoxycarbonyl aminomethyl)-3-methylbutyrate (VII) followed by ethanolysis. Reduction of (V) affords the hydroxy compound (IX) which can be derived to the 3-chloro compound (XII) with thionyl chloride or the acetoxy compound (X) with acetic anhydride. Reaction of (XII) and (X) with diethyl malonate, in the presence of sodium ethoxide, afforded diethyl 1, 2-diethoxycarbonyl-4-isopropyl-3-pyrrolidinemalonate (XIII).
Diethyl 1, 2-diethoxycarbonyl-4-isopropyl-3-pyrrolidinemalonate (XIII) was derived from diethyl 3-acetoxy-4-isopropyl-1, 2-pyrrolidinedicarboxylate and the important question in this reaction is the effect of steric relationship of the acetoxyl and isopropyl groups on the steric configuration of the diethoxycarbonylmethyl group introduced against the isopropyl group present. Therefore, reduction of diethyl 3-oxo-4-isopropyl-1, 2-pyrrolidinedicarboxylate (V) was carried out under various conditions and reduction products were examined. It was thereby found that the steric configuration of the hydroxyl and isopropyl groups was different in the hydroxy compound (IX-i) obtained by reduction with platinum or Raney nickel catalyst and that (IX-ii) obtained by reduction with sodium borohydride. The hydroxy compounds were derived respectively to the acetoxy compounds, (X-i) from (IX-i) and (X-ii) from (IX-ii), proving that the steric configuration of the acetoxyl radical differs in (X-i) and (X-ii). Moreover, substitution of the acetoxyl radical in (X-i) and (X-ii) with diethoxycarbonylmethyl group afforded the same (XIII) whose hydrolysis to 2-carboxy-4-isopropyl-3-pyrrolidineacetic acid (XV) and its optical resolution yielded L-α-dihydroallokainic acid (XVI-i). It was thereby found that (XIII), with sterically stable trans configuration, forms in this reaction irrespective of the configuration of the acetoxyl group to the isopropyl group. This has confirmed the appropriateness of the proposed structure for L-α-dihydroallokainic acid obtained by the reduction of natural L-α-allokainic acid.
In accordance with the method adopted for the synthesis of α-dihydroallokainic acid reported in Parts XXXIX and XL of this series, preliminary tests were with substitution of the isopropyl group with 1-methyl-2-diethylaminoethyl group an then with 1-methyl-2-dimethylaminoethyl group. In these procedures, optimal reaction conditions suitable for these substituents had to be found but the desired diethyl 1, 2-diethoxycarbonyl-4-(1-methyl-2-dimethylaminoethyl)-3-pyrrolidinemalonate (X) was finally obtained. The Hofmann degradation of (X) was carried out to substitute the side chain at 4-position with isopropenyl group and subsequent hydrolysis afforded 2-carboxy-4-isopropenyl-3-pyrrolidineacetic acid (XII). The compound (XIV) obtained by the optical resolution of (XII) with l-ephedrine was found to be identical with L-α-allokainic acid, one of the active components of Digenea simplex AG.
Introduction of 1-methyl-2-dimethylaminoethyl group for later substitution to the isopropenyl group was examined by the use of other groups which are more easily available, easily handled, and more easily derived to the isopropenyl group at later stages, such as 1-methyl-2-methoxyethyl, 1-methyl-2-ethoxyethyl, and 1-methyl-2-phenoxyethyl groups. Using ethyl 2-cyano-3-methyl-4-ethoxybutyrate (I), obtained by the condensation of 1-ethoxy-2-bromopropane and ethyl cyanoacetate, as the starting material, diethyl 1, 2-diethoxycarbonyl-4-(1-methyl-2-ethoxyethyl)-3-pyrrolidinemalonate (VIII) was prepared by series of reaction similar to those reported in the preceding two papers.
A new amino acid, 4-isopropylproline (VI), prepared by three different routes from 2-isopropyl-1, 3-dibromopropane (II), 2-isopropylacrylonitrile (VII), and diethyl 4-isopropyl-2-pyrroline-1, 2-dicarboxylate (XII), was found to be identical and the other theoretically possible steric isomer was not obtained.
Ethyl 2-oxo-3-chloro-5-(1-methyl-2-ethoxyethyl)-3-piperidinecarboxylate (VI) was prepared from 2-(1-methyl-2-ethoxyethyl) acrylonitrile (III) by the same method as that described in Part XLIII of this series. Heating of (VI) with hydrochloric acid and subsequent treatments afforded methyl 1-acetyl-4-(1-methyl-2-ethoxyethyl)-2-pyrrolidinecarboxylate (IX) and its 4-(1-methyl-2-hydroxyethyl) compound (X). On heating (IX) with hydrobromic acid, 1-methyl-2-ethoxyethyl group in 4-position was converted to isopropenyl group, while the treatment of (X) with phosphorus tribromide and organic amine was found to convert the 1-methyl-2-hydroxyethyl group to isopropenyl group. A new amino acid, 4-isopropenylproline (XV), was prepared by the foregoing two different methods.
Heating of diethyl 1, 2-diethoxycarbonyl-4-(1-methyl-2-ethoxyethyl)-3-pyrrolidine-malonate (I) with hydrobromic acid results in the transfer of the 1-methyl-2-ethoxy-ethyl group to an isopropenyl group and treatment of its reaction product gives methyl 2-methoxycarbonyl-4-isopropenyl-3-pyrrolidineacetate (II) and its 1-ethoxy-carbonyl compound (IV). The presence of an isopropenyl group was confirmed by ozonolysis of (II) or catalytic reduction of (IV). Hydrolysis of (IV) afforded DL-α-allokainic acid (VI), which was optically resolved and the l-ephedrine salt (VII) of L-α-allokainic acid agreed with the salt derived from natural L-α-allokainic acid, one of the active components of Digenea simplex AG. Heating of (I) with hydrobromic acid under more drastic conditions and similar treatment as before gave DL-α-isokainic acid (IX), which was optically resolved to a compound (XII) that agreed with L-α-isokainic acid derived from natural L-α-kainic acid. The foregoing facts have shown that the heating of (I) with hydrobromic acid partly changes the isopropenyl group to isopropylidene group and that the formation ratio of the two differs with reaction conditions.
As an intermediate in the synthesis of dihydrokainic acid, diethyl 2-oxo-5-isopropyl-4-piperidinemalonate (VIII-i, -ii) was prepared by the process shown in Chart 2. Ethyl 2-cyano-3-methylbutyrate (I) was hydrolyzed to the carboxylic acid compound (II), then to its chloride (III), and condensed with diethyl malonate in the presence of magnesium ethoxide to the butyroylmalonate compound (IV). Decarboxylation of (IV) by heating gave butyroylacetate compound (V) which was reduced to two kinds of hydroxy-piperidones (VI-i and -ii). Each of these was boiled with acetic anhydride and both afforded the same dihydropyridone compound (VII) which was submitted to the Michael condensation with diethyl malonate to give two kinds of piperidone compound (VIII-i and -ii). (VIII-i) was derived to its half ester (IX-i), ethoxycarbonylmethyl compound (XI-i). (VIII-ii) was also derived through its dicarboxylic acid compound (X-ii) to the carboxymethyl compound (XII-ii), thereby confirming the structure of (VIII-i) and (VIII-ii), and proved that these compounds are stereoisomers with regard to the C4-C5 position. It was assumed that the configuration of the side chain in C4-C5 is in trans in the product (VIII-i) with overwhelmingly large yield and cis in the other product (VIII-ii).
The active methylene in the side chain of the piperidone compound (VIII) was brominated to obtain a bromo-diester compound (XVI), which was saponified to the bromo-carboxylic acid (XVII). Bromination of the dicarboxylic acid (X) gave a dibromo compound (XXII), and that of the half ester (IX) gave the bromo-half ester compound (XIX), whose decarboxylation afforded two kinds of bromo-monoester (XX and XVIII). (XVIII) was also obtained by esterification of (XVII) and saponification of (XX) resulted in isomerization to form (XVII). Alkaline treatment of (XVI), (XVII), (XVIII), and (XX) all afford DL-2-carboxy-4-isopropyl-3-pyrrolidineacetic acid (XXI racemate). L-Form compound (XXI) obtained by the optical resolution of this racemic compound was found to agree with L-α-dihydrokainic acid (L-XXI) obtained by the reduction of natural α-kainic acid.
Synthesis of α-kainic acid in accordance with the synthetic procedures for α-dihydro-kainic acid described in the proceeding paper* was attempted and the pyrrolidine compounds (XIV-i and -ii) were first prepared through the piperidone compound (VIII). Ethyl 2-cyano-3-methyl-4-ethoxybutyrate (I) was saponified to the carboxylic acid (II), derived to the acid chloride (III), and condensed with diethyl malonate to form but-yroylmalonate compound (IV). Its decarboxylation gave the butyroylacetate compound (V), which was reduced to the hydroxypiperidone compound (VI), treated with aceticanhydride to form the dihydropyridone compound (VII), and submitted to the Michael condensation with diethyl malonate to obtain (VIII). Saponification of (VIII) gave the half ester (IX-i and -ii), dicarboxylic acid (X-i), (X-ii). (X-i and -ii) was derived to monocarboxylic acid (XI-i and -ii) and the dibromo compound (XV-i and -ii). The isomers of (IX) and (X) are stereoisomers arising from the carbon bonded with the ethoxymethyl group, and the configuration of the side chain at C4-C5 position in the compounds was assumed to be in trans. (VIII) was then brominated, the bromo compound (XII) obtained was treated with an excess of alkali, and (XIV-i and -ii) were obtained. Saponification of (XII) with 2 moles of alkali afforded the bromomonocarboxylic acid compound (XIII-ii) which was derived to (XIV-ii). From the comparison of the yields of (XIV-i) and (XIV-ii) with that of the isopropyl compound, (XIV-i) was found to be the chief product.
Saponification of the ethoxyl group in the side chain at 4-position of the pyrrolidine compound (XIV-i) with 48% hydrobromic acid to the alcohol (XVI), followed by esterification and N-ethoxycarbonylation afforded (XVIII). Treatment of (XVIII) with phosphorus tribromide to (XIX) and vacuum distillation gave the isopropenyl compound (XX) and its saponification with potassium hydroxide afforded DL-α-kainic acid (XXI). Optical resolution of this compound with l-ephedrine gave two optical isomers one of which was entirely identical with the natural L-α-kainic acid. The other was its antipode, D-α-kainic acid.
As one method for preparing diethyl 2-oxo-5-isopropyl-4-piperidinemalonate (XIII), an intermediate in the synthesis of dihydrokainic acid, diethyl 4-cyano-4-iso-propylglutaconate (III) was prepared from diethyl 4-cyanoglutaconate (II) and selective liberation of the 4-ethoxycarbonyl group in (III) followed by Michael condensation of the product (V) with diethyl malonate gave diethyl (1-ethoxycarbonylmethyl-2-cyano-3-methylbutyl) malonate (XII). High-pressure reduction of (XII) finally gave (XIII), with formation of ethyl 2-oxo-5-isopropyl-4-piperidineacetate (XIV) and ethyl 2-oxo-3-ethoxycarbonyl-5-isopropyl-4-piperidineacetate (XV) as by-products.
In accordance with the synthetic procedures for 2-piperidone derivatives, the intermediates in the synthesis of kainic acid, diethyl 2-oxo-5-(1-methyl-2-ethoxyethyl)-4-piperidimemalonate (IXa) and diethyl 2-oxo-5-(1-methyl-2-dimethylaminaethyl)-4-piperidinemalonate (IXb), were prepared.
γ-Ethoxycarbonyl-γ-nitroketones (V) and (X) were prepared by the Michael condensation of α, β-unsaturated ketone (III) and ethyl nitroacetate or by the application of ethyl nitroacetate to β-tert-amino ketone (IV) or (IX). Catalytic reduction of these compounds with Raney nickel as a catalyst afforded several kinds of ethyl pyrroline-2-carboxylate derivatives, and their structures were discussed.
The metal chelating ability of N-bis(2-chloroethyl)-glycine and -alanine, which are cytotoxic agents, was studied comparing with that of N-bis(2-hydroxyethyl)glycine, sarcosine, and glycine. N-Bis(2-chloroethyl)-glycine and -alanine form chelate compounds only with copper and their stability constants were estimated as log k1 4.90, 4.30 and log k2 3.30, 3.02 respectively, i.e. far weeker than that of the other amino acids compared. The chlorine-liberating velocity of the chelate compound was of the same order as that of the free amino acid. These results suggest that the copper chelates of N-bis(2-chloroethyl)amino acids are unstable and transform easily under hydrolysis to the more stable N-bis(2-hydroxyethyl)amino acid chelates.
Alkaline hydrolysis of the oxidation product (II) of thiamine benzyl disulfide (I) affords thiamine (III) and phenylmethanesulfinic acid (IV), which would suggesd that the structure of (II) should be represented as (A). Hydrolysis in acetic acidity results in the formation of thiamine (III), benzyl phenylmethanesulfonthiolate*** (XI), and dibenzyl disulfide (XII). Refluxing of (II) in ethanol affords thiamine disulfide, thiamine benzyl disulfide and dibenzyl disulfide, while the same reaction in isobutanol gives thiamine disulfide, thiamine benzyl disulfide, thiochrome, and dibenzyl disulfide. Further heating however causes disappearance of thiamine disulfide and thiamine benzyl disulfide and formation of thiochrome, thiothiamine and (XI) is observed. Oxidation of (II) with hydrogen peroxide failed to show the formation of sulfonthiolate*** (XIV).
In order to examine the analgesic activity, 2-(2-dimethylaminoacylamido) benzothiazoles (III) were synthesized by the application of 2-bromoacyl bromide to 6-alkoxyor 4 (5, or 6)-chloro-2-aminobenzothizole (I) to the 2-(2-bromoacylamido) derivatives (II) and its condensation with dimethylamine. Of the starting materials (I), the 5-chloro derivative (VIII) was obtained by the oxidative cyclization from (3-chlorophenyl) thiourea with bromine but the 7-chloro derivative (IX) was also obtained as a by-product. (VIII) was confirmed by its identification with the compound obtained by reductive cyclization of 5-chloro-2-thiocyanatonitrobenzene (X).
In order to study the presence of a tuberculostatic activity, (N-arylglycylamino)-thiazole derivatives were synthesized. By the application of bromoacetyl bromide and pyridine on ethyl 2-amino-4(or 5)-thiazolecarboxylate, 2-bromoacetamidothiazole derivatives were obtained, which gave 2-(N-arylglycyl) aminothiazole derivatives by the condensation with aromatic amines. By the application of hydrazine hydrate on ethyl 2-(N-arylglycyl) amino-4-thiazolecarboxylate, 2-(N-arylglycyl) aminothiazole-4-carbohydrazides were prepared but in a very poor yield, and the main product was arylaminomethanecarbohydrazides (tuberculostatic data shown).
10-Amino and 10-dimethylamino derivatives of 10, 11-dihydrodibenz[b, f]oxepine were prepared and optically active amines were derived by resolution. Their 10-methylamino-, 10-amino-ll-hydroxy-, and 10-dimethylamino-ll-hydroxy derivatives were also prepared.
The effect of the position and kind of substituents on the dissociation as an acid of 26 kinds of compound of Phenylazo-p-cresol and phenylazoresorcinol series, possessing nitro, bromo, methyl, or methoxyl on the phenyl ring, was examined.
By catalytic vapor-phase reaction, using cadmium phosphate-acid clay as a catalyst, 2-ethyl-3-methylpyridine was obtained from allyl alcohol, diethyl ketone, and ammonia, and 2-propyl-3-ethylpyridine from allyl alcohol, dipropyl ketone, and ammonia. When the reaction temperature was 375-400°, the yield of the pyridine base was 25% in case the molar ratio of allyl alcohol to dialkyl ketone was 1:1 and ca. 30% in case this molar ratio was 1.5:1. It was also found that cobalt phosphate is also an excellent catalyst in this reaction besides the above cadmium salt. On the other hand, 2-ethyl-3-methyl- and 2-propyl-3-ethylpyridines were respectively obtained by the application of methyl or ethyl iodide to the lithium derivatives of 2, 3-lutidine and 2-methyl-3-ethylpyridine.
Examinations were made on the structure of the polysaccharide composed of D-xylose, obtained from human placenta, and it was found that it was composed of about 20 molecules of D-xylopyranose, bonded by C1-C4 bond in β-type in a straight chain with a reducing group at one end and with two side chains.
The nitrogen-containing polysaccharide obtained from human placenta was purified and submitted to determinations of molecular weight and number of componental sugars. It was thereby found that this substance is composed of 6 moles of D-galactose, 6 moles of D-mannose, and 8 moles of N-acetyl-D-glucosamine.
The nitrogen-containing polysaccharide obtained from human placenta was submitted to periodate oxidation and methylation. From the result of molar number of periodic acid consumed, molar number of formic acid formed, and from the estimation and determination of the methylated monosaccharides obtained, a structure represented in Fig. 1 was proposed for the polysaccharide.
It has recently been found that glucosone methylphenylhydrazone-2, whose formation was reported in the preceeding paper, should be corrected to D-glucosone methylphenylhydrazone-1, since 1-methyl-1-phenylhydrazine is bonded to C1-position of D-glucosone. Consequently, the bonding position of 1-methyl-1-phenyl hydrazine in various derivatives of this compound is also corrected to the C1-position of the sugar. Examination of the mode of bonding of the sugar and hydrazine at C1-position of these derivatives suggested -CH2-NH-N< bonding, such as that of a sugar and amine in the Amadori rearrangement product, rather than a hydrazone bonding, -CH-N=N<, but details are now under investigation.
An examination was made for the process of regenerating ribonucleic acid from its complex with silver, reported in the preceding paper, and following processes were carried out. 1) To 100cc. of 1% aqueous solution of silver-ribonucleic acid complex, 1cc. of 5% ammonia water and 20cc. of saturated sodium chloride solution are added in that order, and hydrogen sulfide is passed through this solution to precipitate the silver. 2) This solution is then centrifuged, to its supernatant solution is added ethanol, and the precipitate formed is collected. The precipitate is dissolved in distilled water, dialyzed, and ethanol added to the dialyzate in the membrane. The precipitate thereby obtained is washed with ethanol and ether, and dried under a reduced pressure. By such a procedure, white amorphous powder is obtained that agrees with ribonucleic acid in various physical and chemical properties as well as in biological activity, such as the increased production of streptolysin S from Streptococcus hemolyticus, and entirely devoid of silver. This regenerated ribonucleic acid is obtained in 80-90% yield and its purity was found to be far higher than the commercial yeast nucleic acid preparation by the ninhydrin reaction and sulfur detection tests.
The dried flowers of lily of the valley (Convallaria majalis L. var. Keisukei MAKINO or Convallaria Keisukei MIQ.), growing in the Hokkaido area, was extracted with cold methanol, its residual extract was dissolved in ethanol, instead of purification through the lead salt, and acetone-soluble portion was collected. This portion was dissolved in water, shaken with an ethanol-chloroform mixture (1:9), and a portion transiting to this solvent layer was submitted to liquid chromatography through alumina and developed with methanolic chloroform. Convallotoxin was obtained in an yield of about 0.02% against the dried flower.
A kind of carotenoid pigment was isolated from the flowers of Osmanthus fragrans LOUR. var. aurantiacus MAKINO, as deep red scales, m.p. 179.5°, C40H56, which was identified with all-trans-β-carotene, kindly donated by Professor Zechmeister.
A process whereby nucleosides are prepared in a good yield from yeast nucleic acid, as the starting material for the synthesis of nucleotide, coenzymes and their allied compounds, was devised. Extraction of ribonucleic acid (RNA) was made through improvement of the Clarke-Schryver method and 50-60g. of RNA was obtained for 1kg. of dry yeast. Cytosine was abnormally small in this RNA. RNA was also obtained from the baker's yeast, torula yeast, and medicinal yeast, as well as from the brewer's yeast. Preparation of nucleoside by hydrolysis of RNA was examined and following procedure was adopted. After hydrolysis with 50% pyridine, guanosine was removed, a majority of adenosine was removed from ethanolic solution, and the solution was divided into uridine and cytidine-adenosine portions by ion exchanger, Amberlite IR-120. Cytidine and adenosine were separated by sulfate fractionation and cellulose-powder-chromatography. Shortening of the hydrolysis period to one half was effected by preliminary hydrolysis with N sodium hydroxide to nucleotide and then hydrolyzed with pyridine.
Yield of hypoxanthine from 4-amino-2-mercapto-6-pyrimidinol by eight routes of synthesis was comparatively examined. It was found that the yield is poor in the introduction of amino group from 4-amino-6-pyrimidinol. Imidazole cyclization of 4, 5-diamino-2-mercapto-6-pyrimidinol to 2-mercaptohypoxanthine and its desulfurization with Raney nickel to hypoxanthine was found to be the best in the points of experimental procedures and yield.
A series of experiments were carried out in order to establish a method of detecting affected rice infected with Penicilium islandicum. P. islandicum was artificially inoculated on. non-sterilized and sterilized rice, such rice granules were placed on a strip of filter paper in a test tube, and these were incubated for 1-2 weeks at 26-29°, with only a supply of moisture. The pigment produced by metabolism of P. islandicum was extracted and the extract solution was submitted to paper chromatography. The kind and amount of pigments detected were used as the basis for establishing a simple method of detecting rice granules affected with P. islandicum. It was thereby found that the pigments produced from granules inoculated with this fungus and incubated as above were the same as those obtained by pure culture of this fungus on a Czapek medium, with a slight variation in the amount and decrease in the number of pigments.
Examinations were made on the amount and kind of pigments metabolised by Penicillium islandicum when rice granules are infected with P. islandicum and other fungi or bacteria at the same time. It was found that there was no change in the pigments produced in such a case as in pure culture and that the usual metabolic pigments are detected in case different strains of P. islandicum are present on the same rice granules.
A piece of filter paper was soaked in 1% toluene solution of polyethylene (mol. wt., 4000-6000 and 21000) and dried at around 90° to make the paper water-repellent. This treated filter-paper was used for papyrography of essential oil components and good results were obtained.
Paper chromatography of methylated D-glucosamine, D-galactose, and D-mannose was examined and RG values of these were recorded in case of butanol-ethanol-water-ammonia (40:10:49:1) and butanol-acetic acid-water (4:1:1) mixture as the solvents.
By a route similar to the synthesis of 5-butylpicolinic acid from 2-methyl-5-cyanopyridine, 4-butyl- and 4-pentylpicolinic acids were prepared from 2-methyl-4-cyanopyridine. 4-Ethyl- and 4-sec-butyl-picolinic acids were prepared by the method whereby a desired alkyl group is introduced into the 4-position by submitting 4-cyanopyridine to the Grignard reaction and Wolff-Kishner reduction (with hydrogen iodide in the case of sec-butyl group), amino group is introduced into 2-position by the Tschitschibabin reaction, substituted with bromine atom by diazotization reaction, heated with copper cyanide in diphenyl to form a nitrile, and hydrolyzed to the α-picolinic acid.