Reaction of benzoyl nitrate with 2, 4-dimethylquinoline 1-oxide and lepidine 1-oxide in chloroform solution at room temperature was examined. The products obtained from the quinoline compound were 3-benzoyloxy-2, 4-dimethylquinoline (syrup; picrate of needles, m.p. 235-237°), 2-benzoyloxylepidine (prismatic crystals, m.p. 80-82°; picrate of prisms, m.p. 146-148°), and a small amount of yellow needles, m.p. 185-187°, C22H16 O2N4 (assumed to be a glyoxime superoxide-type compound), besides recovery of 27% of the starting material (Chart 1, II). Lepidine 1-oxide produced 3-benzoyloxylepidine (needles, m.p. 18-20°; picrate of microneedles, m.p. 214-215°) besides recovery of 40% of the oxide (Chart 1, III). In both cases, a large amount of the starting material was recovered and the compounds formed by this reaction were those expected to be produced by the action of benzoic anhydride and not the 3-nitro derviatives. This supports the assumed mechanism (Chart 1, I) forwarded by Ochiai and Kaneko for the formation of 3-nitroquinoline 1-oxide from quinoline 1-oxide by the action of benzoyl nitrate. Quinoline 1-oxide forms a stable complex of m.p. 157.5-158.5° with boron trifluoride. Its nitration with benzoyl nitrate under the same conditions as above afforded 4-nitroquinoline 1-oxide in 54% yield and the reaction mechanism shown in Chart 1 was forwarded. Nitration of the boron trifluoride-complex with acid mixture at 15-20° chiefly produces 5- and 8-nitro derivatives, with a small amount of 4-nitro compound as a by-product.
It was assumed that the severence of an N-O bond in quinoline 1-oxide, while its oxygen still retained the electron octet, by the application of a proton or acyl group to quinoline 1-oxide, whose lone-pair electrons of the oxygen are bonded to functions with great electrophilic properties, would result in activation of 2- and 4-, as well as 3-position, of the quinoline to nucleophilic substitution by the resonance of extremely labile quinoline residue left with a nitrongen with sextet electrons (Chart 1). Under such assumption, the crystalline complex of quinoline 1-oxide and boron trifluoride was heated with phosphoric acid or tosyl chloride. When the complex was heated in orthophosphoric acid, a small amount of 3-quinolinol formed besides quinoline and carbostyril, while heating with tosyl chloride produced 3-(p-toluenesulfonyloxy) quinoline (prisms, m.p. 90-92°), besides carbostyril and 4-chloroquinoline.
A new phenolic lactone, m.p. 173.5°, was isolated from the fresh subterranean part of Agrimonia pilosa LEDEB. and was named agrimonolide (I). Molecular formula of (I) agrees with C18H18O5, possessing one methoxyl and two phenolic hydroxyls, one of which is chelated to a lactonic C=O and is not easily methylated. It is a γ- or δ- lactone and the acid obtained on cleavage of the lactone ring easily undergoes decarboxylation to form a compound of m.p. 169°, C17H20O4, which was named agrimonol. Bromination of (I) easily afforded a dibromo (VI) and tribromo (VII) derivatives, while oxidation of (I) and (VI) gave anisic acid (VIII). Oxidation of (VII) afforded 3-bromo-4-methoxybenzoic acid. Oxidation of the dimethyl derivative of (I) formed anisic acid and 3, 5-dimethoxyphthalic acid (XIII). Since potassium salt of the acid obtained on lactone-cleavage of (IV) is levorotatory, it is clear that asymmetric carbon is present in (I). There is no C-methyl group in (I). It was thereby concluded that the structure of agrimonolide would correspond to one of the formulae (XVI), (XVII), and (XVIII).
A few oxidation products and their reduction products of sophoradiol (I), obtained from the dried buds of Sophora japonica L., were comparatively examined with reactivity of known triterpene alcohols and the structure of olean-12-ene-3, 15-diol, -3, 19-diol, or -3, 22-diol was proposed for (I).
Kinetics of the deamination reaction of glycine with nitrous acid was examined and it was confirmed, as did the experimental results of Spero and Schantz, that it is a first-order reaction in the presence of an excess of sodium nitrite. In the case of neurotoxin, application of nitric acid, under the same conditions as for glycine, was found to effect inactivation whose rate progressed by the first-order reaction and at a fast rate. Its half-life is 41.5 minutes at pH 4.0 and 0°C, and 48.5 minutes at pH 4.45 and 0°C. As a result of comparison with deamination reaction of glycine and with past literature, inactivation of neurotoxin by nitrous acid is due to deamination. It is therefore concluded that the essential group responsible for the toxicity of neurotoxin is the amino group. The amino groups present in neurotoxin are that of N-terminal leucine and the ε-amino group of lysine in the peptide chain. Since ε-amino group of lysine is less reactive to nitrous acid than the α-amino group, the essential group responsible for the neurotoxin activity must be the amino group in N-terminal leucine.
The Phellodendron sterol (sterol mixture), obtained from the unsaponifiable matter of Phellodendron amurense RUPR. (family Rutaceae), was derived to its acetate, purified by alumina chromatography, and fractionally recrystallized from ethanol into β-sitosterol and γ-sitosterol. Ultraviolet absorption spectrum of the phellodendron sterol indicated the presence of Δ5, 7-sterol in approx. 0.5%.
Examinations were made on the determination of blood level of isonicotinoylhydrazinopyruvic acid (IP) and free pyruvic acid, and excretion of vitamin B6 in urine, which are problems to be solved in the clinical use of IP as an antituberculosis agent, having the same effect as INAH with less toxicity. From the result of various experiments, following conclusions were drawn: 1) Comparison of paper chromatographic and ion exchanger methods for separatory determination of IP in blood showed that the two methods give well-agreeing values. Paper chromatographic method was found to be more practicable. 2) For the determination of free pyruvic acid in blood after administration of IP, total pyruvic acid, which included the bound form, was measured by the 2, 4-dinitrophenylhydrazine method, and the amount of the free acid was calculated by subtracting the value of pyruvic acid so obtained from IP. 3) The foregoing processes were used to determine IP and free pyruvic acid in blood after administration of IP, and it was found that: a) Blood IP disappeared rapidly after intravenous injection of IP-Na in a rabbit and it was not detected after 2 hours. b) After oral administration of IP-Na in a rabbit, blood level of INAH increased gradually, reached the maximum after about 2 hours, and the high level was maintained for 4-5hours. c) In either of the cases, the amount of free pyruvic acid in blood did not show any increase. 4) Excretion of vitamin B6 in urine clearly increased after administration of IP and showed results similar to that after administration of INAH.
4-Nitrosalicylic acid was acetylated and derived to its acid chloride, and this was condensed with 2-diethylaminoethanethiol to give 2-diethylaminoethyl 2-acetoxy-4-nitrobenzothiolate hydrochloride. Its reduction and deacetylation afforded the objective 2-diethylaminoethyl 2-hydroxy-4-aminobenzothiolate (IX). Condensation of 4-nitrosalicyloyl chloride and 2-diethylaminoethanethiol, and reduction of the nitro compound so produced also gave (IX), with better yield and by a simpler procedure than the former process. Antitubercular action of the hydrochloride of (IX) and its salts of penicillin G and V was examined in comparison with the oxyprocaine-penicillin G salt (I) of Grimme and others. It was found that the antitubercular activity of the penicillin G salt (II) and V salt (III) of (IX) was better than that of (I), and that penicillin V salt was less soluble in water.
The reaction of acetylacetone with the Mannich bases prepared from diethyl acetamidomalonate (I) and diethyl 2-(benzyloxycarbonylamino) malonate (VII) respectively resulted in deacetylation and formation of γ-aminoketone derivatives, diethyl 2-acetamido-2-(2-acetylethyl) malonate (IV) and diethyl 2-(2-acetylethyl)-2-(benzyloxycarbonylamino) malonate (IX). Cyclization of (IV) and (IX), followed by the reduction of 3, 4-dihydro-2H-pyrrolenine so obtained, and hydrolysis of its product afforded 5-methylproline. In this reaction, the use of (I) or (VIII) as the starting material gave different intermediates and showed different mode of reaction, affording two kinds of 5-methylproline, sterically isomeric in respect to C-2 and C-5 positions, of m.p. 188° (XVI) and of m.p. 207° (XVI′).
Formation of a 3, 4-dihydro-2H-pyrrolenine derivative by reduction of γ-nitroketone with Zinc dust and glacial acetic acid was reported earlier. In the present series, reduction of various γ-nitroketone derivatives with zinc dust and glacial acetic acid was found to form a pyrrole derivative besides the 3, 4-dihydro-2H-pyrrolenine derivative when one carbonyl group, such as carboxyl and acetyl, was present in the position α to carbonyl taking part in cyclization, while only the pyrrole derivative was formed when carbonyl groups were present in both α-and α′-positions. In the absence of a carbonyl group, only the 3, 4-dihydro-2H-pyrrolenine derivative and not pyrrole derivative was found to be formed.
The basic substance of C13H23O3N, obtained on reductive cyclization of ethyl 2-ethyl-3-isopropyl-4-nitrobutyrate with zinc dust and glacial acetic acid, was assumed to be ethyl 3-isopropyl-4-ethyl-5-hydroxy-5-methyl-2-pyrroline-4-carboxylate (III), from its physicochemical properties and various decomposition reactions. Some presumptions were made on the mechanism of formation of (III) and of pyrrole derivatives.
Two kinds of bitter principle were isolated from the dried leaves of Isodon trichocarpus (MAXIM.) KUDO. The one of m.p. 297-299° (decomp.), C20H26(28)O6, was named enmein (I), and the other melted at 263-265° with decomposition. (I) forms a dihydro compound (II) and a diacetate (III), suggesting the presence of at least one double bond and two hydroxyls, one of which was found to be secondary by chromium trioxide oxidation of (I). Saponification of (III) with oxalic acid afforded monoacetylenmein (IV) while saponification of (III) with hydrochloric acid and ethanol afforded (V), C20H26(28)O6⋅C2H5OH. The presence of at least one lactone was presumed from the result of saponification of (I) with ethanol and potassium hydroxide.
Antifungal thiol esters and aniline or amino acid were reacted under physiological conditions to presume the mechanism of their antifungal action. Reaction with aniline afforded acyl anilides, same as under organic chemical conditions. Examinations were also made in this reaction on the effect of pH (Table I), effect of additives (Table II), and changes in reactivity of various thiol esters (Table III). Amino acids used were β-alanine, 4-aminobutyric acid, L-histidine, and L-lysine, and their acylated derivatives were isolated for confirmation. Reaction with β-alanine was followed by the Folin and Van Slyke methods (Figs. 1 and 2) and those of L-histidine and L-lysine were followed by paper chromatography. The reaction products of L-lysine with phenyl acetothiolate (or caprothiolate) were submitted to polarography and their polarograms (Figs. 3 and 4) showed that their reduction waves underwent a marked change when reacted for a certain length of time. This was considered to be a valuable datum for presuming the state of acylation with thiol esters in a dilute solution.
Antifungal thiol esters were found to have fairly strong antibacterial activity against putrefaction bacteria and pathogenic bacteria (Table I). Effect of amino acids on antifungal spectrum of thiol esters was examined by the addition of 4-aminobutyric acid, L-lysine, L-histidine, L-cysteine, L-methionine, or glutathione to phenyl acetothiolate, phenyl benzothiolate, and phenyl 3-pyridinecarbothiolate (Table II, III, and IV). As a result, marked antagonism was found to exist in thiol-amino acids like cysteine and glutathione. From the effect of addition of redox agents like ferric chloride and sodium thiosulfate, and Zn2+ and Cu2+ ions (Tables V, VI, and VII), the antifungal activity of these thiol esters was found to be markedly increased by Cu2+ while no influence was found from the addition of an redox agent. These facts are endorsed by the result of addition of ferric chloride and ascorbic acid on the anti-spore action of phenyl acetothiolate against Aspergillus niger (Fig. 1). These results indicate that the anti-fungal action of thiol esters is a specific inhibition of transacylation to thiol-amino acid.
It was found that antifungal thiol esters had a marked specificity in inhibiting the production of spores in Aspergillus niger in much lower concentration than that required in its inhibition against growth of mycelium and swelling of spores of this fungus (Fig. 1). The effect of phenyl acetothiolate, phenyl benzothiolate, and phenyl 3-pyridinecarbothiolate against respiration of spores, cultured for 0, 3 and 6 hours, with glucose as a substrate, was examined and results shown in Fig. 2 were obtained. At the same time, sensitivity of various spores cultivated for the specified time was examined by contacting the spores for 20 minutes with phenyl acetothiolate and phenyl 3-pyridinecarbothiolate and the results are shown in Fig. 3. The foregoing facts have shown that thiol esters have marked inhibiting activities against Aspergillus niger, especially to its swollen spores, and a correlationship was found to exist between sporocidal activity and inhibition of respiration enzyme. Considerations were made on the mode of action of antifungal thiol esters from the present and earlier series of experimental observations.
The degree of denaturation of casein when iodinated under various conditions was followed by paper electrophoresis. Under milder conditions, effecting partial iodination, α, β-peaks are still observed but after complete iodination, oxidation of the β-peak occurs and the phoretic pattern becomes indistinct. In incubated iodocasein, separation of α- and β-peaks becomes impossible.
The heartwood of Ginkgo biloba L. was extracted with ether and approx. 5% of essential oil was obtained together with 0.52% of d-sesamin and 0.15% of crystals of m.p. 77-78°, C17H34O. Lowpressure distillation of this essential oil afforded about 40% of main distillate as pale yellow oil, b.p7 165-170°; d224 0.978, n20D 1.509, [α]22D+44.36°. Its molecular formula corresponded to C15H20O2 and it formed a semicarbazone of m.p. 142-143°, an oxime of m.p. 64°, and a 2, 4-dinitrophenylhydrazone of m.p. 140°. It seemed to be an unknown sesquiterpene ketone and was named bilobanone. Catalytic reduction of bilobanone with palladium-carbon resulted in absorption of two moles of hydrogen. The oxygen atom other than that forming the ketone was assumed to be in ether linkage and this was in good agreement with its infrared absorption data (9.05μ). Reduction of the ketone with lithium aluminum hydride afforded a compound, C15H22O2, b.p2 175-180°, and its acetylation formed a compound of b.p2 85-95, C17H24O4. Wolff-Kischner reduction of the ketone gave a product of b.p2 140-143°, C15H22O, and dehydrogenation of bilobanone with selenium gave a product of b.p2 130-140°, C13H18O, and a small amount of sublimable crystals, m.p. 212-213°.
In order to find reasons for differences in quality and pharmaceutical effect of two similar crude drugs, Yamato-toki (I), the root of Angelica acutiloba, and Hokkai-toki (II), that of A. acutiloba var. Sugiyamae, studies were made on their components. Both contained sugars like glucose, fructose, sucrose, and starch, and saponification of a high-boiling fraction of the essential oil afforded a substance considered to be valerophenone-o-carboxylic acid as its derivative. Presence of safrol was not detected in the medium-boiling fraction. The unsaponifiable matter from ether extracts of both afforded β-sitosterol. The largest difference between the components of the two drugs is the larger amount of extract obtained from (I) by various solvents, with greater amount of sucrose, and a low-boiling fraction of the essential oil containing p-cymene as the main component.
In connection with the formation of thiamine anhydride* (I) by the application of benzenesulfonyl chloride to alkaline solution of thiamine, the reaction was carried out under ice-cooling in order to isolate its reaction intermediate. In this case, thiamine disulfide (V) was obtained in a good yield, while O, O′-bis (benzenelsulfonyl)-thiamine disulfide (VIIIa) and diphenyl disulfone (VI) were also isolated at the same time. Application of p-toluenesulfonyl chloride to alkaline solution of thiamine, under ice-cooling, afforded thiamine disulfide (V), its ditosylate (VIIIb), and di-p-tolyl disulfone (VII). On warming (VIIIa) or (VIIIb) with alkali, in ethanol, thiamine anhydride (I) was formed easily. (I) was also obtained in a good yield by the application of benzenesulfonyl chloride at room temperature to thiamine disulfide (V), formed by periodate oxidation of alkaline solution of thiamine. O-Benzenesulfonylthiamine benzyl (or propyl) disulfide also easily formed (I) on alkali treatment.
Attempt to obtain O-benzenesulfonylthiamine (Va) by application of benzenesulfonyl chloride to thiamine was not realized. Application benzenesulfonyl chloride to pyridine solution of thiothiamine (II) at a low temperature afforded O-benzenesulfonylthiothiamine (IVa) whose oxidation with hydrogen peroxide gave O-benzenesulfonylthiamine (Va), m.p. 206° (decomp.). (Va) was also obtained on cysteine treatment of O-benzenesulfonylthiamine benzyl disulfide (IVa). O-(p-Tolyl) thiamine (Vb) and O-methanesulfonylthiamine (Vc) were obtained by similar procedure from their corresponding thiothiamine derivatives (VIa, b, c). These O-sulfonyl esters (Va, b, c) of thiamine changed to thiamine anhydride (I) on being warmed in alkaline state and this reaction was found to take place even at room temperature. As for the formation of (I) by the application of benzenesulfonyl chloride to alkaline solution of thiamine, two routes can be considered; one of going through thiamine disulfide to from its O, O′-bis (benzene)-sulfonyl ester and the other of direct formation from O-benzenesulfonylthiamine.
Condensation of 2-dialkoxymethyl-3-alkoxypropionitrile (I, II) and acetamidine in ethanol affords 2-methyl-4-amino-5-acetamidomethylpyrimidine (VI) via 2, 7-dimethyl-3, 4-dihydropyrimido [4, 5-d] pyrimidine (V) but during the course of this reaction, formation of a reaction intermediate with absorption maximum at around 275 mμ was detected through ultraviolet spectrum. Attempt was made to isolate this intermediate and to determine its structure but neither its picrate nor hydrochloride could be isolated and this reaction mixture decolorized bromine. By introduction of dry hydrogen chloride gas to this solution, ethyl 2-methyl-3, 4-dihydro-5-pyrimidinecarboxylate (X) and 2-methyl-4-amino-5-alkoxymethylpyrimidines (VIII, IX) were obtained. Catalytic reduction of (X) over palladium-carbon gave its tetrahydro compound (XIII), which is obtained by similar reduction of the 4-chloro compound (XII). It was assumed from these experimental facts that the structure of this intermediate is 2-acetamidinomethylene-3-alkoxymethylpropionitrile (III, III′) which was thought to have been formed by condensation after the nitrile group had been converted to imido ester type by dry hydrogen chloride gas. This pyrimidine condensation and formation of a dihydropyrimidine ring by hydrochloric acid is considered to be a new type of reaction.
Condensation of D-galactose and acetone, with phosphoric acid, phosphorus pentoxide, and zinc chloride as catalysts, affords 1, 2; 3, 4-diisopropylidene-D-galactose whose further condensation with fatty acid chloride, in the presence of pyridine, gave eight kinds of D-galactose esters of fatty acid, e.g. butyrate, m.p. 75.5°; caproate, b.p2 167°; caprylate, b.p2 180° caprate, b.p0.02 177°; laurate, b.p0.035 186°, myristate, b.p0.001 205° palmitate, b.p0.005 229° stearate, b.p0.003 210°. These isopropylidene compounds were hydrolyzed with acid catalyst and D-galactose monoesters of fatty acid were obtained, butyrate and caproate as syrupy substances; caprylate, m.p. 155° (t.p. 112°), caprate, m.p. 168° (t.p. 114°); laurate, m.p. 180° (t.p. 124°), myristate, m.p. 176° (t.p. 121°), palmitate, m.p. 175° (t.p. 121°), and stearate, m.p. 175° (t.p. 119°) (t.p. transition point). Of these, esters of caprylate to stearate are considered to form liquid crystals.
In connection with relationship between chemical structure and pharmacological activity of α-methyl-2-methoxyphenethylamines, the isomeric α-ethyl-2-methoxybenzylamines were prepared. α-Ethyl-2-methoxybenzylamines were obtained by amination of 1-chloro-1-(2-methoxyphenyl) propane, formed by addition of hydrogen chloride to 2-propenylanisole. N-Methyl-α-ethyl-2-methoxybenzylamine was obtained by reductive amination with methylamine and activated aluminum, and also by the reaction of N-(2-methoxybenzylidene) methylamine and ethylmagnesium iodide.
In order to remove the characteristic bitterness of chloramphenicol and to obtain its derivatives still retaining its antibacterial activity, two series of derivatives were prepared. One series was derivatives of D-(-)-threo-1-p-nitrophenyl-2-dichloroacetamido-3-alkylcarbamoyloxy-1-propanol (chloramphenicol alkylcarbamate) in which the alkyls were from C5H11 to C11H23 and the other was a series of derivatives of D-(-)-threo-1-p-nitrophenyl-2-dichloroacetamido-3-alkoxycarbonyloxy-1-propanol (chloramphenicol alkyloxyformate) in which the alkyls were C2H5 and C3H7. The first series of compounds were obtained from fatty acid chlorides, which were derived to azides, submitted to the Curtius rearrangement to form alkyl isocyanate, and condensed with chloramphenicol. The second series were obtained by dissolving chloramphenicol in chloroform and reacted with ethyl or propyl chloroformate, in the presence of pyridine.
Alkaloidal content was examined in Skimmia japonica THUNB. var. intermedia KOMATSU form. repens (NAKAI) HARA (Japanese name “Tsurushikimi”) of Rutaceae family, growing in the suburbs of Kyoto, and the known skimmianine was isolated as the tertiary base. Three kinds of new water-soluble bases were also isolated. Base-A was obtained from the leaves and rhizome of the plant collected in January and the base formed a chloride, m.p. 191-192.5° (decomp.) (C9H18ONCl. 1/4H2O), a styphnate, m.p. 188° (decomp.) (C9H18ON⋅C6H2O8N3), and a picrate, m.p. 202-204° (decomp.) (C9H18ON⋅C6H2O7N3). The infrared spectrum of this base exhibited absorptions in the range corresponding to >C=O and -NH+, while its ultraviolet spectrum showed no characteristic absorptions in the range of 220 to 350mμ. Base-B, obtained from the rhizome of the plant collecting during August, gave a chloride of m.p. 158° (decomp.) (C6H14ONCl) and its infrared spectrum exhibited absorptions in the ranges corresponding to >C=O and -NH+, while no characteristic absorption was observed in its ultraviolet spectrum in the range of 220 to 350mμ. Base-C, obtained from the leaves of the plant collected during August, formed a styphnate, m.p. 103-106° (decomp.) (C15H22O3N⋅C6H2O8N3), and a chloride, m.p. 79-81° (C15H22ONCl⋅2H2O).
As a method for simple detection of Meprobamate (2-methyl-2-propyl-1, 3-propanediol dicarbamate), paper partition chromatography was carried out and the Ehrlich reagent (2% hydrochloric acid solution of p-dimethylaminobenzaldehyde) was found to be suitable as a coloring reagent. Rf values of Meprobamate by various developing solvents were determined (Table I). Separatory detection of Meprobamate from a mixture with urea and ammonium chloride (Table II) and from a compound powder (Table III) was carried out.
There has not been any report on the colorimetric determination of Meprobamate and it was found by present series of work that p-dimethylaminobenzaldehyde, used as a hydrochloric acid solution, in the coloring of spots in paper partition chromatography, was found to be applicable to colorimetry. Addition of this reagent as a solution in hydrochloric, glacial acetic, or 19 N sulfuric acid to methanolic solution of Meprobamate produces yellow color which has an absorption maximum at 416mμ. The best sensitivity is obtained with a 3.0% solution in conc. hydrochloric acid. This color produced becomes stable after 5minutes and sensitivity is the best when reaction is carried out under ice-cooling. The coloring reagent solution should be prepared extemporaneously and this process enables determination of Meprobamate in a tablet.