1) Biosynthesis of folic acid was carried out by the culture of Lactobacillus arabinosus in the medium used for folic acid determination. In this case, pteroic acid, p-aminobenzoylglutamic acid, p-aminobenzoic acid, and pteridine-6-carboxylic acid, all assumed to be the intermediates of folic acid, were added to the medium but no effects were observed with the exception of PABA.
2) The amount of folic acid formed by L. arabinosus is not necessarily proportional to the degree of the bacterial growth.
3) Biosynthesis of folic acid is inhibited by the presence of sulfanilamides. Addition of the foregoing folic acid intermediates, in order to find the inhibition point, showed that the inhibition was the smallest when p-aminobenzoylglutamic acid was added, from which it was assumed that the sulfanilamides damaged the bonding of PABA and glutamic acid.
4) Inhibition of the growth of Lactobacillus arabinosus by sulfathiazole, when cultured in a synthetic medium used for the quantitative determination of folic acid, is antagonized by folic acid, p-aminobenzoylglutamic acid, and p-aminobenzoic acid, the strength being in that order. p-Aminobenzoylglutamic acid antagonizes sulfanilamides in 4-5 times the strength of PAPA.
5) Folic acid is the essential nutrient of Lactobacillus caseii and is not inhibited by sulfanilamides.

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Folic acid-like actions and antagonism were examined in 16 kinds of compounds possessing pteridine ring, using Streptococcus faecalis and Lactobacillus caseii, and following results were obtained:
1) 2-Methyl-4, 6, 7-trihydroxypteridine and 2, 4, 7-trihydroxy-6-carboxy-4-aminopteroylglutamic acid antagonize folic acid.
2) Methylleucopterine, 2, 4, 7-trihydroxy-6-isobutyric acid pteridine, leucopterin, and xanthopterin show folic acid-like action, though weak, on S. faecalis.
3) Pteroic acid, pteroic acid-6-diethylaminoethyl ester, and 6-piperidiniummethyl pteridine iodide all show folic acid-like action on L. caseii and S. faecalis in 200th to 1, 600th of that of folic acid.
From these experimental results, it was assumed that, outside of folic and pteroic acids that possess substituent in 6-position of pteridine, compounds bonded to large molecules other than carboxyl and acetic acid groups are more easily able to change to substances with folic acid actions. When a methyl group is introduced into 2-position of leucopterin, the antagonism is more stronger when the substituent at 6-position is -CH₂COOH than -COOH.

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Growth of Lactobacillus arabinosus, Leuconostoc mesenteroides, and Escherichia coli was tested by substituting p-nitrobenzoic acid for p-aminobenzoic acid (PABA). With L. arabinosus, it showed approximately 80% the activity of PAPA, 90-98% of PABA with Leuc. mesenteroides, but no difference was found to have been shown with E. coli. The antagonism of p-nitrobenzoic acid against sulfathiazole was found to be about 1/10 that of PABA with L. arabinosus. It was assumed that the above bacteria utilized p-nitrobenzoic acid by reducing it to PABA.

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N-(α′-Quinolyl)-α-pyridone was obtained by warming quinoline N-oxide and α-bromopyridine on a water bath. The same pyridone was obtained by heating the sodium salt of α-pyridone and α-bromoquinoline at 200° in the presence of copper dust. In a similar manner, N-(α′-quinolyl)-carbostyril was obtained from quinoline N-oxide and α-bromoquinoline. This carbostyril was also obtained by heating the sodium salt of carbostyril and α-bromoquinoline at 200° in the presence of copper dust.

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The fact that the compounds (III), (IV), (V), and (VI), obtained by heating the respective sodium salts of α-pyridone and carbostyril with α-bromopyridine or α-bromoquinoline with copper dust are not in ether form (II) but in keto form (III) was proved physicochemically. The absorption maxima in the ultraviolet absorption spectra of these compounds and their medium effect showed the presence of a carbonyl group. The infrared absorption of (VI) also showed a strong absorption at 6.05μ assumed to be due to the carbonyl group of CONRR'. The potentiometric titration values of (III) and (V) indicated that their basicity is quite weak.

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Relationship between the concentration and specific gravity, and refractive index were measured in the systems of water-glycol, glycol-diethylene glycol, and diethylene glycol-triethylene glycol. The concentration-specific gravity relationship gave a curve with a very slight bend while the relationship between concentration and refractive index was linear. It was found possible, therefore, to calculate the concentration, x, of each component by the measurement of a refractive index, n, of a mixture of two substances. Following empirical formulae for each system were proposed.
Water-Glycol: glycol%, x=1006.0n-1341.0.
Glycol-Diethylene glycol: diethylene glycol%, x=6493.5n-9301.3.
Diethylene glycol-Triethylene glycol: triethylene glycol%, x=10526.3n-15240.0

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During the hydrolysis of ethylene chlorhydrin with alkali, the presence of an excessive amount of alkali or amine resulted in their acting as a catalyst and ethylene oxide formed was found to react selectively with glycols rather than with water. Larger the concentration of ethylene chlorhydrin, less was the amount of ethylene glycol formed, with attendant increase in the amount of di-, tri-, and poly-ethylene glycols. Alkaline hydrolysis of ethylene chlorhydrin solution, added with ethylene or diethylene glycol results in the larger formation of a higher diethylene or triethylene glycol. The larger the amount of glycol added, larger was the amount of diethylene glycol formed, with attendant decrease in the amount of glycol formed from chlorhydrin.

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From the 70% alcoholic extract of the air-dried bark of Engelhardtia formosana Hay, yellow plates or needles, m.p. 177-180° (yield, 5.66-7.56%), and colorless needles, m.p. 295-296° (yield, 0.10-0.11%) were isolated and they were respectively designated as Glycoside A and Glycoside B. Hydrolysis of the Glycoside A yielded l-rhamnose and two kinds of aglycones, yellow needles, m.p. 276-277°, and colerless silky needles, m.p. 231-232°, which were respectively designated as Aglycone A and Aglycone B. Aglycone A corresponds to the formula C₁₅H₁₀O₅ and gives a tetraacetate, C₁₅H₆O₆(COCH₃)₄, of m.p. 182°, a trimethyl ether, C₁₅H₇O₃(OCH₃)₃, of m.p. 146° by diazomethane (giving an acetate, C₁₅H₆O₃(OCH₃)₃(COCH₃), of m.p. 170°), and a tetramethyl ether, C₁₅H₆O₂(OCH₃)₄, of m.p. 157° with a large excess of diazomethane or by the application of dimethyl sulfate and 30% potassium hydroxide at a room temperature. Aglycone A was proved to be identical with 3, 5, 7, 4′-tetrahydroxyflavone (kaempferol), m.p. 277°, by mixed fusion with the sample prepared by the method of Robinson-Shinoda. Application of diazomethane to 5, 7-dihydroxy-3, 4′-dimethoxyflavone (III) yielded 5-hydroxy-3, 7, 4′-trimethoxyflavone (IV), m.p. 146-147° (giving an acetate of m.p. 170°) whose further methylation with dimethyl sulfate and alkali yielded 3, 5, 7, 4′-tetramethoxyflavone (V), m.p. 157°. (IV) was found to be identical with the trimethyl ether, and (V), with tetramethyl ether, obtained from Aglycone A.

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The Aglycone B (I), m.p. 231-232°, extracted from the bark of Engelhardtia formosana Hay correspond to formula C₁₅H₁₂O₆, gives a tetraacetate (amorphous) of m.p. 50°, C₁₅H₈O₆(CH₃CO)₄⋅H₂O, pentaacetate (amorphous) of m.p. 200°, C₁₅H₇O₆(CH₃CO)₅, monomethyl ether of m.p. 171-172°, C₁₅H₁₁O₅(OCH₃), dimethyl ether of m.p. 189-190°, C₁₅H₁₀O₄(OCH₃)₂, trimethyl ether (IV) (amorphous) of m.p. 60°, C₁₅H₉O₃(OCH₃)₃, tetramethyl ether (VII) (amorphous) of m.p. 50°, C₁₅H₈O₂(OCH₃)₄, and tetrabenzoate (amorphous) of m.p. 130°, C₁₅H₈O₆(COC₆H₅)₄. Air oxidation of hot aqueous solution of (I) gave 3, 5, 7, 4′-tetrahydroxyflavone (kaempferol) (II), and dehydrogenation of trimethyl ether (IV) with palladium-black and cinnamic acid or application of approximately equimolar amount of alkali to the methanolic solution of (IV), yielded 3-hydroxy-5, 7, 4′-trimethoxyflavone (V). Application of alcoholic potash to the tetramethyl ether (VII) gave α-methoxychalcone (VIII). It was assumed from these experimental results that the structure of Aglycone B would be 3, 5, 7, 4′-tetrahydroxyflavanone (I″).

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Reduction of 3, 5, 7, 4′-tetrahydroxyflavone (kaempferol) with sodium hydrosulfite by the method of Pew gave rac-3, 5, 7, 4′-tetrahydroxyflavone (II) as colorless needles, m.p. 231-232°. This substance was identical in properties and melting point with the racemic compound obtained by boiling Aglycone B with hydrochloric acid. Some time ago, Kimura obtained 3-hydroxy-5, 7, 4′-trimethoxyflavanone, related to (II), by the cyclization of 2′-hydroxy-4, 4′, 6′-trimethoxy-α-methoxychalcone (III) but the substance obtained above was found by the present experiments to be 2-hydroxy-4, 6-dimethoxy-2-(4′-methoxybenzyl)-coumaranone (V), and this reaction was found to be accompanied by the formation of 2, 4, 6-trimethoxy-2-(4′-methoxybenzyl)-coumaranone (IV), m.p. 127°. Application of acetic anhydride and conc. sulfuric acid to (V) yielded 2-acetoxy-4, 6-dimethoxy-2-(4′-methoxybenzyl)-coumaranone (VI), m.p. 135-136°, and 4, 6, 4′-trimeth-oxybenzalcoumaranone (VII), m.p. 166-167°. Confirmation of (VII) was made by its preparation from 2′-hydroxy-4′, 6′, 4-trimethoxychalcone by treatment by the Oyamada method in accordance with the Geissmann-Fukushima method.

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Salts of penicillin with p-aminomethylphenyl sulfone monomethylamide, dimethylamide, diethylamide, and p-aminomethylphenyl methyl sulfone were prepared. The p-aminomethylphenyl sulfone diethylamide salt of penicillin was found to be extremely sparingly soluble in water and the effective blood level in rabbit was found to be maintained for over 50 hours.

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Cultivation tests on Japanese summer and autumn buckwheat (Fagopyrum esculentum Moench var. aestivum and var. autumnale Makino), diploid and tetraploid buckwheat, and Tartary buckwheat (F. tataricum Gaertner) were carried out at Kasukabe during 1951 for the purpose of examining rutin-content. Relationship between the sowing time and yield of crop, rutin-content, and yield of rutin per 10 ares was chiefly examined with the diploid, tetraploid, and Tartary buckwheat. The results obtained were as follows:
1) Both the rutin-content and yield of rutin per 10 ares were larger in the summer and autumn buckwheat cultivated in the spring than those cultivated in autumn, and it was confirmed that the spring cultivation of autumn buckwheat gave better results than that of summer buckwheat (cf. Tables I and II).
2) Both rutin-content and yield of rutin per 10 ares were found to be larger in the diploid and tetraploid buckwheat cultivation during the spring than those sown in autumn. Comparison of the diploid and tetraploid cultivation at the same time showed no re-markable difference in the yield of crop per 10 ares but the rutin-content and yield of rutin per 10 ares were smaller in the tetraploid (maxima, 3.21% and 1.693kg.) than in the diploid (maxima, 5.61% and 3.589kg.) (cf. Table III).
3) Tartary buckwheat gave better results in the point of fresh useful crop than the summer and autumn buckwheat. While the yield of fresh crop, rutin-content, and yield of rutin per 10 ares of Tartary buckwheat cultivated during the spring was inferior to those of Japanese buckwheat, those cultivated in the summer and autumn showed better results (cf. Table IV).

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1) Aqueous solution of berberine hydrochloride shows absorption maxima at 227.5, 262.5, 345, and 420mμ
2) Light absorption (e) was measured by the Beckmann spectrophotometer at 420mμ (l=1cm.) in different concentrations (γ/100cc.). The following experimental equation was calculated by the method of least squares from these data:
γ=7023e+25.19......(1) Limit of error (2σ): ±113γ
as berberine γ=6610e+25.19......(2) Limit of error (2σ): ±98γ
3) Berberine in crude drugs was measured by the three following methods: (A) e_420mμ of the acidified aqueous extract; (B) e_420mμ of the diluted hydrochloric acid solution of the isolated berberine hydriodide; and (C) acetone-berberine method of J.P. VI.
4) The values obtained from the above three methods agreed well, and the rate of detectable berberine by respective method is 92.5% (A), 90.4% (B), and 90.0% (C).

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Hydrolysis of the saponin, isolated from the leaf of Rhodea japonica Roth, gave a sapogenin, m.p. 293-295° (decomp.), corresponding to formula C₂₇H₄₄O₄. This sapogenin does not precipitate with digitonin but undergoes isomerization by alcoholic hydrochloric acid. From these and the fact that it easily gives a monobromo substitutent, it was assumed to be a dihydroxysteroidal sapogenin possessing a normal spiroketal side chain.

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It was confirmed by infrared spectral analysis that rhodea-sapogenin and rhodea-isosapogenin are steroidal sapogenins respectively possessing normal and isospiroketal side chain. At the same time, rhodea-sapogenin diacetate was decomposed to pregnenolone (or allopregnenolone) derivative through pseudo compound. The pregnenolone or al-lopregnenolone thereby obtained also failed to precipitate with digitonin.

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Rhodea-sapogenin, C₂₇H₄₄O₄, a dihydroxysteroidal sapogenin possessing a normal-type spiroketal side chain, submits to chromic acid oxidation and gives rhodea-sapogenic acid, C₂₇H₄₂O₆, a dicarboxylic acid formed by cleavage at C₂-C₃. Since rhodea-isosapogenin is not identical with either gitogenin or its C₂, C₃-isomer, rhodea-sapogenic acid was assumed to be identical with texogenic acid. Since both rhodea-sapogenin and its derivative, 16-pregnen-2, 3-diol-20-one do not precipitate with digitonin nor form acetonides, rhodea-sapogenin must possess spirostan-2β, 3α-diol structure.

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During the course of revaluation of tannin-bearing drugs, microanalytic method for gallotannins was followed in order to find their effect in human body, especially their change in the intestines. Satisfactory results were obtained by the modified Hagendorn-Jensen method, used in the determination of blood sugar, as well as with colorimetric method with ammonium molybdate.

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Gallotannin was fractionated with egg albumin, and extracted the combined tannin and egg albumin with 95% alcohol. It was found that tannins of higher polarization did not combine with egg albumin and showed greater mobility than others by the paper electrophoresis. It was assumed that, in order to obtain a clearer images of electrophoretic pattern of gallotannins, the existence of borate was necessary in weak alkalinity.

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Crude fatty acids were obtained in approximately 15% yield from the fruits of Angelica ursina Benth. et Hook. The distillation of the methyl esters of the acids at 3mm. pressure gave Fractions (A), (B), and (C) (cf. Table I). (A) Fraction failed to yield any acid substance. About 42% of solid and about 58% of liquid fatty acids were respectively isolated from (B) and (C) Fractions by the lead salt method. Palmitic acid, m.p. 60-61°, was obtained from Fraction (B), and crystals of m.p. 27-28° from Fraction (C). From the results of elemental analyses, elaidination, and paper chromatography, the crystals were found to be a mixture of petroselic and petroselidic acids. Permanganate oxidation of the liquid acid yielded 6, 7-dihydroxy- and 9, 10, 12, 13-tetra-hydroxystearic acids. These experimental results showed that the fatty acids composing the fruit oil of Angelica ursina are petroselic, petroselidic, palmitic, and linolic acids.

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Crude fatty acids were obtained in approximately 9.3% yield from the fruit of Bupleurum falcatum L. Distillation of the methyl ester of these acids at 4mm. pressure gave Fractions (A) and (B) (Table I). Both (A) and (B) fractions were respectively isolated into about 28% of solid and about 72% of liquid acids. (A) fraction gave crystals of m.p. 28.5-29° which were found to be a mixture of petroselic and petroselidic acids from the results of elemental analyses, elaidination, and paper chromatography. Fraction (B) yielded crystals of m.p. 29-30°, whose elemental analyses, elaidination, and paper chromatography showed it to be petroselic acid with a minute amount of petroselidic acids. Oxidation of the liquid acid by the Hazula method gave 9, 10, 12, 13-tetrahydroxystearic acid from which the fatty acids composing the fruit oil of Bupleurum falcatum were found to be petroselic, petroselidic, and linolic acids.

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Since the raw materials could not be obtained in a large amount, the fatty acids of the fruit oil of Osmorhiza aristata Makino et Yabe, Pleurospermum kamtschaticum Hoffm., and Seseli libanotis Koch var. daucifolia Franch et Sav., were led to the hydroxamic acids, and were submitted to qualitative estimation of each fatty acid using the circular paper chromatography similar to that described in Part VIII of this series. The fatty acids from the fruit oil of the first two plants were separated preliminarily into solid and liquid acids, and each was chromatographed as its hydroxamic acid. From each were obtained petroselic, petroselidic, palmitic, oleic, and linolic acids. Since the amount of Seseli fruit oil was so small it could not be separated into liquid and solid acids and was therefore derived to the hydroxamic acid, per se, and chromato-graphed. Only the presence of petroselic and linolic acid was confirmed.

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In the previous papers of this series, the writer reported the finding of the presence of petroselidic acid, the trans isomer of petroselic acid, with the latter in the fruit oil of Umbelliferae plants. It was also shown in Part VI that petroselic acid in the fruit oil underwent gradual elaidination to petroselidic acid by the action of ultraviolet light but that such elaidination never occurred by the processes of extraction and isolation. It was therefore concluded that the petroselidic acid detected in fruit oil had been formed by the gradual elaidination of petroselic acid by the ultraviolet rays in the sunlight because there had been no example of the presence of a trans-type fatty acid of oleic acid series in plants. However, isolation of a mixture of petroselic and petroselidic acids as crystals of m.p. 27-28.5° and of m.p. 29-31°, respectively, from the unripe fruit of Angelica ursina Benth. et Hook. and Bupleurum falcatum L., has shown clearly that a minute amount of petroselidic acid was present originally with petroselidic acid in the fruit. It was also clarified that petroselidic acid was present in the fruit oil of Daucus carota L., Apium graveolens L., Petroselinum sativum Hoffm., and Cryptotaenia japonica Hassk.

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Ethyl α-(2, 4, 6-trinitrophenyl)-acetoacetate, m.p. 97-98°, (2, 4, 6-trinitrophenyl)-acetone, m.p. 77-78°, ethyl α-(2, 4, 6-trinitrophenyl)-benzoylacetate, m.p. 154-155°, and ω-(2, 4, 6-trinitrophenyl)-acetophenone, m.p. 134-135°, were prepared and their Rf values were determined by paper chromatography. Absorption spectra of their alkaline coloration were determined and it was found that the absorption maximum in the visible range was present only at 515mμ.

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Condensation of 1, 3, 5-trinitrobenzene and methyl ketones (acetone and acetophenone) in the presence of alkali gave some black needle crystals which showed an absorption spectrum similar to that of color reaction produced by 1, 3, 5-trinitrobenzene and active methylene compound in the presence of alkali. This complex decomposes into respective components in an acid solution but in the presence of hydrogen peroxide, 1, 3, 5-trinitro-benzene cannot be obtained and the picryl compound of the active methylene group is formed. Results of paper chromatographic observation showed that the active methylene group in the complex molecule had a tendency to undergo partial substitution with other active methylene compound when they come into contact. From these facts and from the values of elemental analyses and molecular weight determination, it was concluded that the structure of the above complexes should be respresented by formulae (VII) and (VIII).

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Phenylethynylcarbinol, prepared by the alkynol synthesis of benzaldehyde and acetylene, was reduced to phenylethylcarbinol and subsequently oxidized to propiophenone. In a similar manner, 3, 4-methylenedioxypropiophenone was synthesized from piperonal. Hydrolysis of phenyl ethynyl ketone gave benzoyl methyl ketone.

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The corm of a garden variety meadow saffron, Colchicum autamnale L.; of white flower, was harvested during the early part of September. From the dried corm were extracted 0.114% of an alkaloid of colchicine series which Santavy designated as Substance F, 0.034% of colchicine, and 2.5% of sucrose.

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Following derivatives were prepared from Substance F, m.p. 183-185°, C₂₁H₂₅O₅N, isolated from white meadow saffron corm. Monoacetate (II), m.p. 227-229°, [α]_D¹⁷: -232°, C₂₃H₂₇O₆N; monomethyl compound (III), m.p. 200-203°, [α]_D²⁰: -106°, C₂₂H₂₇O₅N; nitroso compound (IV), m.p. 187-190°, [α]_D²⁰: -99°, C₂₁H₂₄O₆N₂. Hydrolysis of Substance F with diluted hydrochloric acid gave the demethylated compound (V), m.p. 132-135°, [α]_D¹⁷: -226°, C₂₀H₂₃O₅N. Similar hydrolysis of (II) gave C₂₂H₂₅O₅N (VI), m.p. 189-190°, [α]_D²⁰: -279°, and of (III), C₂₁H₂₅O₅ (VII), m.p. 129-131°, [α]_D²²: -225°. Treatment of Substance F with conc. ammonia yielded an amino compound (VIII), m.p. 128-131° (decomp.), [α]_D²²: -133°, C₂₀H₂₄O₄N₂⋅1/2 CH₃OH. Amination of (II) in a similar manner gave C₂₂H₂₆O₅N₂⋅1/2CH₃COCH₃ (IX), m.p. 122-125° (decomp.), [α]_D²²: -293°.

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Following derivatives of Substance F were also prepared. Hydrolyses of (VIII) and (IX) with sodium hydroxide solution respectively yielded (V) and (VI). Application of sodium methoxide or methanolic potash to Substance F and (II) respectively gave C₂₀H₂₃O₅N (X), m.p. 256-258° (decomp.), [α]_D¹⁷: -160°, and C₂₂H₂₅O₆N (IX), m.p. 283-284° (decomp.), [α]_D²⁰: -143°. Acetylation of (X) gave (XI) whose methylation yielded C₂₃H₂₇O₆N (XII), m.p. 162-165°, [α]_D²³: -152°.

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The structure of the Substance F was assumed from its properties, its derivatives, and the color reactions. In order to prove this structure, N-methyldeacetylcolchiceine, m.p. 129-131°, C₂₁H₂₅O₅N, was prepared from colchicine. This substance was found to be identical in melting points and various properties with a substance (VII) of m.p. 129-131°, C₂₁H₂₅O₅N, obtained by the hydrolysis with diluted hydrochloric acid of (III), C₂₂H₂₇O₅N, formed by the methylation of Substance F. It follows, therefore, that the structure of Substance F may be represented by Formula D or E in Fig. 3.

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It was assumed that the structure of Substance F would be represented by formula D or E in Fig. 1, but the infrared absorption spectrum made it possible to conclude that the structure is N-methyldeacetylcolchicine, represented by formula D (normal). The formation of the various derivatives of Substance F obtained to date and their structures were clarified (Fig. 4). It was also found that Substance F and its derivatives possessed characteristic action against the animal and vegetable cells like that of colchicine.

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It was found that aldoximes undergo dehydration when heated with organic amides to form a nitrile. Formamide, acetamide, and p-toluenesulfonamide were used as the organic amide, and their reaction with α-benzaldoxime, p-sulfonamidobenzaldoxime, and butyraldoxime yielded the corresponding nitriles.

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Degradation of the total alkaloid contained in ergot fluidextract was observed during 125 days at 0° to 2° and at 25-26°. The alkaloidal content decreased rapidly at 25-26° but no decrease was observed at 0° to 2°. Effect of the addition of stabilizers such as l-ascorbic acid, cysteine hydrochloride, thiourea, and sodium thiosulfate, was found to prevent alkaloidal degradation in the fluidextract, thiourea being especially effective.

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Recently, Backer and Boer recommended the use of N-nitroso-p-toluenesulfone-methylamide (IV) as the starting material for diazomethane. The present writers reëxamined this experiment and its stability, and found (IV) to be more stable than nitrosomethylurethane and nitrosomethylurea, heretofore used as the materials for diazomethane. It was also proved that (IV) could be maintained for a fairly long period, even during the summer months with atmospheric temperature of around 36°, if kept in a closed desiccator, without undergoing decomposition.

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