In addition to the two components reported previously, another substance was isolated from the root of Angelica pubescens MAXIM. (Umbelliferae) as white microneedles, m. p. 256-257°, C11H8O4; U. V. λmaxEtOH 257, 309, 332 mμ; I. R. λmaxNujol 5.7, 5.95μ. Oxime, m. p. 225°, C11H9O4N. The substance (II) obtained on opening of the lactone ring formed a 2, 4-dinitrophenylhydrazone, m. p. 275° (decomp.). The substance possesses one methoxyl but no hydroxyl. (I) is a new substance as a plant component but is similar to the substance obtained by Späth as the decomposition intermediate product of ostruthin methyl ether. The structure of (I) was established in a different manner. Clemmensen-Martin reduction of (I) afforded white needles (III), m. p. 134-134.5°, C11H10O3, and a substance, C11H12O3, of m. p. 93-94°. The lactone ring in (III) was opened to afford a substance (IV) which was decomposed with potassium permanganate, yielding white needles, m. p. 119-121°, C10H12O3. This substance was found to be identical with 2, 4-dimethoxy-5-methylbenzaldehyde, which was synthesized by another route from cresorcinol. Therefore, (II) is 6-methyl-7-methoxycoumarin and (I) would be 7-methoxy-6-coumarinaldehyde, which was named angelical. The glabra-lactone obtained earlier from Angelica glabra MAKINO was not obtained from the present material.
A new coumarin compound, glabra-lactone, had been isolated earlier from the root of Angelica glabra MAKINO and its structure had been proposed. Later, following several substances were obtained from the mother liquor after separation of glabra-lactone. White crystals (A), m. p. 256-257° (corr.), C11H8O4; white crystals (B), m. p. 83-84°, C16H15O3; a small amount of phenolic substance (C), m. p. 166-167°, C15H16O5; acid (D), m. p. 63-64°, C5H8O2; and a liquid acid (E), b.p18 85-91°. (A) was found to be identical with angelical, isolated from the root of A. pubescens MAXIM., found to be 7-methoxy-6-coumarinaldehyde. (B) was identified as osthol from its melting point, composition, and result of chromium trioxide oxidation. (C) exhibits marked bluish fluorescence under ultraviolet light and was assumed to be a phenolic coumarin derivative, but no detailed examination was made. (D) and (E) were considered to be tiglic and angelic acids from their p-bromophenacyl esters. Umbelliferone was detected by microchemical method but it was not isolated as crystals. This is the first time that osthol had been isolated from Japanese umbelliferous plants.
Several kinds of 3-phenoxypyridines were prepared from 3-pyridinol. 2, 3′-Dipyridyl ethers were also prepared and nitrated, affording 5-nitro-2, 3′-dipyridyl ether, the nitro group of which was located by decomposition with piperidine and by the synthesis of this compound from 2-chloro-5-nitropyridine and 3-pyridinol. Reduction of this nitro compound with stannous chloride and hydrochloric acid gave the 5-amino derivative while catalytic reduction with palladium-carbon in methanol afforded 5, 5′-azoxy compound.
Application of carbonyl sulfide to aminoacetonitrile and o-methoxybenzaldehyde in ethanol afforded 5-o-methoxybenzylideneamino-2-thiazolol (I). Similar reaction with anisaldehyde, salicylaldehyde, and p-hydroxybenzaldehyde afforded the corresponding 5-p-methoxy-(II), 5-o-hydroxy-(III), and 5-p-hydroxy-benzylideneamino-2-thiazolol (IV). Application of alkyl halide to the sodium salt of (I), (II), and 5-p-dimethylaminobenzylideneamino-2-thiazolol yielded the corresponding 2-alkyl-5-arylideneaminothiazoles.
In order to obtain melanocyte stimulating hormone (MSH) of high purity, extraction of bovine posterior pituitary gland was carried out. Crude MSH of 20-30γ/U. was obtained from gland by extracting with 0.5% acetic acid, water and dehyd. ethanol successively. The crude MSH was submitted to repeated countercurrent distribution with butanol-acetic acid-water (4:1:5) mixture as a solvent and 11-26 tubes, and purified MSH of the highest purity of 1.88γ/U, or ca. 550U/mg., was obtained. This purified MSH was submitted to paper electrophoresis at pH 11.15, 8.7, 4.0, and 3.15, and a ninhydrin-coloring substance was isolated, besides the main spot, in those at pH 11.15 and 4.0. The composite amino acids of MSH were examined by the ring chromatography of its hydrolyzate and the presence of 18 kinds of amino acids was detected. The unit of potency was expressed by the potency of MSH corresponding to 0.5mg. of the Posterior Pituitary Reference Standard J. P. VI, as 1 unit.
The principle (MG) giving positive Mainini reaction, isolated from human placental villus membrane and considered to be approximately uniform according to electrophoresis and ultracentrifugation, was submitted to oxidation by performic acid to find where cystine, one of the composite amino acids, is situated in the MG molecule and to find its relation to the efficacy. The oxidation product was further reduced to sever the -S-S- bond and various changes attendant in this reaction were examined. It was thereby assumed that cystine is not in the terminal position in the MG molecule, that -S-S- bond is necessary for the appearance of the effect, and that MG molecule is formed by the bonding of an open polypeptide chain through the -S-S- bond of cystine. Further, in order to find a part of chemical structure of MG, its terminal amino acids were examined by the DNP and carboxypeptidase methods and it was determined that its N-terminal amino acid is valine and C-terminal amino acid, leucine.
The Ekbom method of reducing 3-nitrobenzenesulfonyl chloride (I) with hydriodic acid was improved to effect the reduction with red phosphorus and a small amount of iodine by which a process was devised for the manufacture of bis(3-nitrophenyl) disulfide. The reaction conditions were examined in detail from the point of industrial process and it was determined that the optimal conditions were the calculated amount, one atom, of red phosphorus to one mole of (I), 1/100 the calculated 2.5 moles of iodine, reaction temperature of 80°, and reaction time of 1-1.5 hours. Further, the amount of red phosphorus was examined by the use of benzenesulfonyl chloride (II) and it was found that even with the use of less than calculated amount of red phosphorus, the reduction of (II) progresses to the disulfide (IV) and the intermediate formed in the Ekbom method, the disulfoxide (V), is not formed and further, that the use of red phosphorus in excess of the amount calculated resulted, unlike in the case of the Ekbom method, in further reduction of the disulfide (IV) to thiophenol (III). It was concluded that the reason for this is because the reduction agent in the Ekbom method is a combination of hydriodic acid and iodine while that in the present method is a natant hydriodic acid itself.
The Ekbom method as improved by the writer was expected to be useful as a process for the preparation of alkylated, arylated, or aralkylated heterocyclic disulfides, not possessing other functional groups in general and the process was applied to alkane-, arene-, and aralkaneylsulfonyl chlorides. Corresponding disulfides were obtained from alkane- and arenesulfonyl chlorides but phenylmethane-sulfonyl chloride, as one of the aralkane series, only afforded dibenzyl sulfide and not the disulfide. Of the heterocyclic sulfonyl chlorides submitted to the reaction, 2-thiophenesulfonyl chloride failed to afford any product under these conditions and the starting material was recovered. Even in this case, the disulfide was obtained by the addition of a calculated amount of iodine and carrying out the reaction at a low temperature.
It has been found by the preceding experiments that the reduction of arenesulfonyl chlorides with red phosphorus in the presence of iodine catalyst affords the corresponding diaryl disulfides. This process was then applied to arenesulfonyl chlorides possessing reducible groups as the functional radical, such as nitro, halogen, and azo group and it was found that this improved method is also useful as a process for preparing diaryl disulfides possessing reducible groups.
It has been shown in the preceding experiment that the process of reducing arenesulfonyl chlorides with red phosphorus in the presence of iodine catalyst is useful for the preparation of diaryl disulfides possessing a reducible group. The process was then applied to arenesulfonyl chlorides possessing hydrolyzable groups, such as cyano, acetamido, and ether and ester bondings. It was thereby learned that depending on the position of the cyano group, the cyano group is hydrolyzed together with the reduction of the sulfonyl chloride group. Other hydrolyzable groups remained intact and corresponding disulfides were obtained.
The Ekbom method improved by the writer was applied to compounds possessing atomic groups related to sulfonyl chloride. The sulfonic acid and sulfone are not reduced but sulfinic acid, sulfenyl chloride, selfenamide, disulfoxide, and sulfohydrazide easily form corresponding disulfides under the reaction conditions selected. It was also found that sulfonamides and sulfoxides would be reduced under a more drastic conditions. As a result, the reduction mechanism for the formation of disulfide from sulfonyl chloride, sulfohydrazide, and sulfonamide was assumed to be in a following process: -SO2Cl → -SOCl → -SO2H → -SO2-S- → -S-S- -SO2NHNH2 → -SO2H → -SO2-S- → -S-S- -SO2NH2 → -SONH2 → -SO2H → -S-S-
Some considerations were made on the mechanism of the formation of dibenzyl sulfide (II) by the reaction of phenylmethanesulfonyl chloride (I) with red phosphorus, in the presence of iodine catalyst. A part of (I) is reduced through dibenzyl disulfide to phenylmethanethiol (V). The remaining part of (I) undergoes pyrolysis at the same time to form benzyl chloride (III), which is changed to benzyl iodide (IV) by the action of hydriodic acid. Finally, (II) is formed by the condensation of (V) and (IV).
It had earlier been concluded that the formation of dibenzyl sulfide from phenylmethanesulfonyl chloride by red phosphorus and iodine involved the formation of phenylmethanethiol by reduction. It was assumed that, if phenylmethanesulfonyl chloride is reduced to the thiol, addition of 4-nitrobenzyl chloride in the reaction system of phenylmethanesulfonyl chloride would afford a mixed-type sulfide, benzyl 4-nitrobenzyl sulfide, together with dibenzyl sulfide. The experiment, however, afforded only the symmetrical bis (4-nitrobenzyl) sulfide alone. The reason for this was clarified as follows: phenylmethanesulfonyl chloride is reduced to form phenylmethanethiol, as expected. On the other hand, 4-nitrobenzyl chloride added into this reaction system is changed to 4-nitrobenzyl iodide by hydriodic acid and the condensation of the thiol and the iodide results in the formation of a mixedtype benzyl 4-nitrobenzyl sulfide as an intermediate. This mixed-type sulfide undergoes substitution reaction with 4-nitrobenzyl iodide present in excess and the symmetrical bis (4-nitrobenzyl) sulfide is formed. This substitution is a new reaction in sulfide-type compounds.
de Smet obtained the corresponding disulfide from haloarenesulfonyl chloride by reduction with palladium catalyst and reported that there was no formation of a further reduced thiol because the thiol is a catalyst poison. Anticipating the formation of bisaminophenyl disulfide by the catalytic reduction of bisnitrophenyl disulfide, bis(2-nitrophenyl) (I), bis(3-nitrophenyl) (II), and bis(4-nitrophenyl) (III) disulfides were submitted to catalytic reduction with platinum oxide as a catalyst. The corresponding diamino compound was obtained quantitatively from (II), but (I) and (III) were resistant to reduction. Only when the amount of platinum was increased and the reaction time prolonged, (I) afforded the diamino compound and a fair amount of the thiol, while (III) afforded only the thiol compound. When the amount of hydrogen absorbed was reduced to around 1/6, (I) afforded the diamino compound and a minute amount of the thiol and (III) a fair amount of the thiol with the diamino compound. From these facts, it was concluded that, in this reduction, the nitro group is preferentially reduced and the position of the amino group so formed affects the reducibility of the -S-S- bond and that the catalyst-poison effect of the SH group, as pointed out by de Smet, becomes weak according to the position of the substituent.
Water-soluble vitamin A derivative was obtained by the formation of an ester of vitamin A alcohol and methoxypolyethyleneoxyglycolic acid, prepared from methoxypolyethyleneglycol. As the esterification reaction, dehydrochlorination from acid chloride and vitamin A alcohol, ester exchange between methyl ester of an acid and vitamin A alcohol, and removal of potassium chloride from acid chloride and potassium salt of vitamin A were examined and it was found that all these processes afforded water-soluble, yellow ester by purification of the reaction product by chromatography through weak alumina. The ultraviolet absorption spectrum of this ester was identical with that of vitamin A alcohol.
Methylation of coixol in ether solution with diazomethane and purification through alumina chromatography affords O-methylated compound of m. p. 55° and N-methylated compound of m. p. 103°. From determination by ultraviolet absorption spectra, the ratio of O-methyl- to N-methylcoixol is 40.5:59.5. This fact reveals that coixol is present, at least in the ether solution under application of diazomethane, as a mixture of tautomers of 60% of the lactam type and 40% of the lactim type. Methylcoixol alone can be obtained by the application of sodium methoxide to 2-chloro-6-methoxybenzoxazole. Methylation of coixol with methyl iodide in the presence of alkali affords only N-methylcoixol. Methylation of 4-, 5-, and 7-methoxy-2(3H)-benzoxazolone with diazomethane and purification by chromatography give the corresponding O-methylated derivatives (m. p. 78°, 40-41.5°, and 58.5-59.5°) and N-methylated derivatives (m. p. 105°, 1.31-132°, and 127-128°).
Acceleration of pyridoxine deficiency was examined with 2, 5-dimethyl-4-aminopyrimidine (I) and 2, 6-dimethyl-4-aminopyrimidine (II), the homologs of 2-methyl-4-amino-5-hydroxymethylpyrimidine (OMP) and possessing a specific spasmodic action. Healthy rats of H-1 strain, weighing 40-60g., were fed with synthetic pyridoxine-deficient diet containing 1mg. of the compound per rat per day. The rats in the group administered with (I) in the diet failed to grow after 1-2 weeks and showed a marked symptoms of pyridoxine deficiency after 5 weeks, indicating the same results as with the control group administered with OMP. On the other hand, the rats in the group administered with (II) in the diet showed the same growth curve as those in the control group with pyridoxine-deficient diet alone. According to histological observations of the livers and kidneys of these rats after 5 weeks, marked damages were observed in those fed with (I) or OMP but there was no abnormality in the group fed with (II), as in the control group with pyridoxine-deficient diet.
Detailed investigations have been made on insularine, the main alkaloid of Cyclea insularis (MAKINO) DIELS and an assumed structural formula (I) was forwarded. However, steric configuration of the two asymmetric centers of insularine has been left unsolved. This question was solved in the present series of experiments by cleavage reaction of insularine with sodium in liquid ammonia. Cleavage of insularine afforded two kinds of crystalline phenolic bases, A and B, and one kind of noncrystalline phenolic base, C. Of these, B base agreed with l-N-methylcoclaurine (IV). A is a new base, not found in any literature to date, corresponding to the composition of C20H25O3N, which was designated l-homoarmepavine and determined as l-1-(3-methyl-4-hydroxybenzyl)-2-methyl-6, 7-dimethoxy-1, 2, 3, 4-tetrahydroisoquinoline (III). O-Alkylation of the C base followed by second cleavage with sodium in liquid ammonia afforded l-homoarmepavine (III) and l-O, O-dialkyl-N-methylcoclaurine (VI), from which the C base was found to be a bis-type structure like (Va) formed by the partial cleavage of the depsidan ring in insularine. These experimental results have proved that the steric configuration of the two asymmetric centers in insularine (I) is l-form in both and that the structure (I) proposed by Tomita and Uyeo is correct.
Matsukawa and others detected the formation of thiothiamine during air oxidation of aqueous solution of free thiamine but later, Zima and others showed that these reactions were instituted by hydrogen sulfide on thiamine and that air oxidation was unnecessary. Reëxamination of Zima's experiments was carried out with examination of various sources for sulfur supply anticipated in this reaction, and it was confirmed that the substance responsible for this reaction is sulfur itself. It is assumed that this sulfur is formed by the oxidation of hydrogen sulfide which is produced by the decomposition of thiamine and that air is required in this reaction.
When aqueous solution of the sodium salt of thiol-type thiamine is warmed, there is an evolution of hydrogen sulfide and butanolic extract of this reaction solution affords a new substance of m. p. 171-172°. The molecular formula of this substance, C12H16O2N4, agrees with those of a compound formed by the liberation of H2S from thiamine. A new substance of m. p. 238° is obtained similarly from the 5-methyithiazolium homolog (II) of thiamine. These substances were assumed to be a pyrimidodiazepine compounds (V and VI) from the infrared spectral measurements, chemical reactions, and syntheses of their decomposition products.
In order to determine the structure (IV or V) of l-phanostenine, the phenolic aporphine-type base contained in Stephania Sasakii HAYATA (Menispermaceae), dl-1, 2-methylenedioxy-9-hydroxy-10-methoxyaporphine (V), m. p. 111-113°, was synthesized and its ultraviolet and infrared absorption spectra were compared with those of the natural product. They were clearly different and showed that phanostenine does not take the structure represented by (V).
Hey and Lobs recently synthesized dl-1, 2-methylenedioxy-9-methoxy-10-hydroxy-aporphine (III) and reported that the free base is an unstable substance melting at 126-129°. Reëxamination of this reaction revealed that the pure substance of (III) came in crystals of m. p. 209-210° and it was assumed that (III) obtained by Hey and Lobs is an impure substance. Comparison of ultraviolet and infrared absorption spectra of (III) obtained here with l-phanostenine, m. p. 210°, the alkaloid of Stephania Sasakii HAYATA, showed them to be identical. It follows, therefore, that the structure of l-phanostenine would be represented by (III).
Cleavage reaction of isotetrandrine (I) with metallic lithium in liquid ammonia, with benzene or toluene as a solvent, proceeds as with metallic sodium or potassium and l-O, O, N-trimethylcoclaurine (III) and d-N-methylcoclaurine (IV) are formed almost quantitatively as the bisected bases. However, the same reaction of (I) with dioxane as a solvent, affords, besides the foregoing (III) and (IV), two kinds of a phenolic base with a composition of C19H23O3N. The amount of the nonphenolic portion formed in this case is extremely small. The two kinds of phenolic base melted at 132° and 162°, and identified as polymorphs. Oxidation of its ethyl ether with cold potassium permanganate afforded 1-oxo-2-methyl-6-ethoxy-7-methoxy-1, 2, 3, 4-tetrahydroisoquinoline (XIII), m. p. 97°, from which the structure of the phenol base was proved to be l-1-(4-methoxybenzyl)-2-methyl-6-hydroxy-7-methoxy-1, 2, 3, 4-tetrahydroisoquinoline (XI), formed by the secondary demethylation of (III) produced by the cleavage.
By the Ullmann reaction of bromobenzonitrile and potassium phenoxide, 2-, 3-, and 4-cyanodiphenyl ethers were prepared and their cleavage reaction with metallic sodium in liquid ammonia was examined. In the case of 2-cyano (I) and 4-cyano (II) compounds, the main decomposition products were benzylamine and phenol, and a trace of dibenzylamine was obtained as a by-product. On the other hand, 3-cyano compound was found to form 3-amidinodiphenyl ether as the main product, with a trace of phenol. As a result, it was found that this reaction proceeded towards severance of ether-type oxygen constituting the diphenyl ether of identical type, shown by (I) and (II) in the case of 2- and 4-cyano compounds and that, at the same time, the cyano group was reduced to the benzylamine type. On the contrary, the ether-type oxygen linkage in 3-cyano compound was comparatively resistant to the severance compared to that in the 2- and 4-cyanocompounds.
Quantitative determination of a mixture of 2-, 3-, and 4-nitro-l-chlorobenzenes, which was difficult to determine by the hitherto existing method, was attempted by infrared absorption spectral measurements. Examination of the results by the Youden's assay method revealed that the standard deviation was 0.63% in the 2-nitro compound, 0.60% in 4-nitro compound, and 0.33% in the 3-nitro compound, without any deviation, and this was found to be a useful method of analysis.
Attempts were made to determine a mixture of 2, 4-, 2, 6-, and 3, 4-dinitro-1-chlorobenzene, which was difficult to determine by the hitherto existing method, by infrared absorption spectra. Examination of results obtained by determination of a standard mixture sample by the Youden's assay method showed standard deviation to be 0.56% for the 2, 4-dinitro compound, 1.68% for the 2, 6-dinitro compound, and 0.51% for the 3, 4-dinitro compound, and indicated that this is a useful method for this kind of analysis.
Reaction of the sodium salt of thiamine and phenylmethanesulfonyl chloride affords, besides thiamine disulfide, a minute amount of two kinds of crystals of m. p. 201°(decomp.) and 148°(decomp.). The structures of these substances were assumed from infrared absorption spectra and others to be O, O′-diphenylmethanesulfonylthiamine disulfide (V) for that of m. p. 201°(decomp.) and O-phenylmethane-sulfonylthiamine disulfide (VI) for that of m. p. 148°(decomp.), and they were confirmed by syntheses.
Reaction of mercuric acetate and sodium undecylenate in aqueous solution results in immediate precipitation of a mercury compound (II). In order to determine the structure of this compound, it was treated with potassium bromide and bromine to substitute the mercury with bromine and oxobromoundecanoic acid (VI) was obtained. Its debromination with sodium amalgam in ethanol or catalytic reduction with palladium black in methanol afforded 10-oxoundecanoic acid (VIII), m. p. 59°, whose semicarbazone (IX), m. p. 136°, agreed with data for this compound. It follows, therefore, that (VI) is 10-oxo-11-bromoundecanoic acid and the original mercury compound (II) would be 10-hydroxy-11-acetoxymercuriundecanoic acid.
The presence of triterpenoidal substances was found in 11 kinds of plants belonging to Oleaceae family by the simple and direct test method of treating the dried leaf powder with acetic anhydride and conc. sulfuric acid in a watch glass. Further paper chromatographic treatment of the leaves of Jasminum odoratissimum L., developed with 4:1 mixture of benzene and xylene and 1:4 mixture of benzene and toluene, revealed the presence of two kinds of a triterpenoid. Thus, 10.5g. of crude triterpenoid was separated from 700g. of powdered leaf of J. odoratissimum and purification of the crude substance yielded two kinds of crystalline products of m. p. 302-303° and m. p. 278-279°. These were respectively identified as oleanolic acid and ursolic acid by the preparation of their derivatives, elemental analyses, infrared absorption spectra, and mixed fusion with authentic samples. This indicated that oleanolic acid is also contained in the Jasmimum species.
6, 7-Trimethylenedioxy-1, 2, 3, 4-tetrahydroisoquinoline (VIII) and its N-methyl derivative (X) were synthesized by the Bischler-Napieralski reaction from 1, 3-dibromo-propane (I) and protocatechualdehyde (II).
Microdetermination of dulcin by colorimetry was devised. The color developed by the modified Jorissen reaction, on addition of a small amount of glacial acetic acid, turns into a violet solution (λmax 550mμ). By measuring the optical density of this solution at 550mμ, 30-360γ of dulcin in 1cc. of the solution can be determined. This method was found to be comparatively specific to dulcin.
Fustin, fisetin, sitosteryl β-D-glucoside, and a structurally unknown pigment were isolated in crystalline form from the heartwood of Rhus tricocarpa MIQ. D-Glucose and L-rhamnose were identified by paper chromatography. Only sitosteryl β-D-glucoside was obtained from the white peripheral wood.
The product obtained from the reaction of o-acetotoluidide and chloral in conc. sulfuric acid failed to be crystallized but its reduction with zinc dust and glacial acetic acid gave crystals of m. p. 156°. Its structure was clarified by the formation of 3-acetamido-4-methylbenzoic acid by its dehydrochlorination and oxidation.