Oxygenation reactions of skatole catalyzed by N, N'-ethylenebis (salicylideniminato) Co (II) [Co (salen)], N, N'-ethylenebis (acetylacetoniminato) Co (II) [Co (acacen)], Co (II)-complex of α, β, γ, δ-tetra (p-methoxyphenyl) porphine [Co (p-OCH₃) TPP] and Co (II)-complex of phthalocyanine (CoPc) were investigated. Remarkable repression of the oxygenation was observed upon addition of a Lewis base such as pyridine, imidazole or N-methylimidazole to the reaction medium. This phenomenon was thought to indicate that the oxygenation proceeds through a ternary complex of the type skatole-Co-complex-O₂. The reaction rate constants and activation energies of all the reactions were also evaluated.

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Carbon-13 and proton nuclear magnetic resonance studies were conducted on 2-aminoand 2-substituted amino-5, 6-dihydroxy-1, 2, 3, 4-tetrahydro-1-naphthalenols, which have a very potent β₂-adrenoceptor-stimulating activity, especially in the trans isomer. The results suggested that in the trans isomer, the saturated part of the tetralin skeleton takes a half-chair conformation having both hydroxy and alkylamino groups in di-equatorial orientation. The structure coincides with the crystal structure of trans-2-cyclobutylamino-5, 6-dihydroxy-1, 2, 3, 4-tetrahydro-1-naphthalenol hydrobromide. The measurement of proton relaxation times of the trans-2-isopropyl derivative in solution indicated the existence of two equilibrium conformers related to the isopropylamino group, one having a conformation very similar to that of the cyclobutylamino analog in its solid state with respect to the C (2)-N⁺bond.

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An iron complex, "astechrome, "was isolated from Aspergillus terreus IFO 6123, and its structure was determined.

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Oxidation of N-methyl (or phenyl)-N'-(4-methylpyrid-2-yl) thiourea (Ia, b) with nickel peroxide (Ni-PO) under reflux in benzene or acetonitrile afforded the corresponding ureas (IIa, b). N-(2-Hydroxy-5-methylphenyl)-N'-methylthiourea (IVa) was synthesized by the reaction of 2-amino-4-methylphenol (III) and methyl isothiocyanate in benzene under reflux. However, the reaction of III and phenyl isothiocyanate in benzene under reflux did not afford the thiourea (IVb) but IVb was obtained in ethanol at room temperature. Ni-PO oxidation of thioureas (IVa-f) in acetonitrile at room temperature afforded 2-substituted aminobenzoxazoles (VIIa-f) in good yields. The reaction mechanisms of Ni-PO and thioureas (Ia, b and IVa-f) are discussed.

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The reactions of 6-bromomethyl-5-formyl-1, 3-dimethyluracil (1) and its hydrazones (6a and 6b) with nucleophiles were investigated. Treatment of 1 with primary amines or hydrazines afforded pyrrolo [3, 4-d] pyrimidines or pyrimido [4, 5-d] pyridazines, respectively. When 6-bromomethyl-1, 3-dimethyluracil-5-carboxaldehyde tosylhydrazone (6a) was treated with hydrazine hydrate, it was readily converted into pyrrolo [3, 4-d] pyrimidine (7) and pyrimido [4, 5-d] pyridazine (8). The reaction of 6-bromomethyl-1, 3-dimethyluracil-5-carboxaldehyde acetylhydrazone (6b) with hydrazine hydrate gave N-aminopyrrolo [3, 4-d] pyrimidine (9).

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Glycyrrhetylamino acids (5a-c) were prepared by the condensation of glycyrrhetic acid (GA) with amino acids (glycine, γ-aminobutyric acid, and ε-aminohexanoic acid), which were selected for use as chemical bridges between the hapten and carrier protein in an enzyme immunoassay (EIA) for GA. The condensation was carried out in the presence of dicyclohexylcarbodiimide (method A), diphenyl phosphorazidate (method B) or diethyl phosphorocyanidate (method C), and method C gave the desired glycyrrhetylamino acids (5a-c) in the best yields. β-Galactosidase was used as the labeled enzyme and was conjugated with GA by the N-hydroxysuccinimide ester method. Separation of bound and free fractions was performed by a double antibody method using a goat antiserum to rabbit IgG. 7-β-D-Galactopyranosyloxy-4-methylcoumarin was used as substrate for the fluorometric assay of β-galactosidase activity. A satisfactory standard curve for GA was obtained in the range of 2.5-250 ng/ml.

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Irradiation of the methylpyridine N-imides (3b-g) condensed with a thiophene, furan, or pyrrole ring on the c-side of the pyridine ring gave the corresponding novel fused 1H-1, 3-(5) and/or 3H-2, 3-diazepines (6), together with the aminopyridines (7) and the parent fused pyridines (1), whereas the fused pyridine N-imide (3a) having no methyl group gave only the aminopyridine derivative (4). This photolysis may proceed by rearrangement to two kinds of diaziridine intermediates, (8) and (9) ; the latter may give the 2, 3-diazepines (6) directly by ring-expansion, whereas the former may further rearrange to the aziridine intermediate (10), followed by ring-expansion to give the 1, 3-diazepines (5). Some reactions of the diazepines (5 and 6) thus obtained were also examined.

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The reaction of 5a-acetyl-6a-carbethoxy-5a, 6a-dihydro-6H-cyclopropa [5a, 6a] pyrazolo [1, 5-a] pyrimidine-3-carbonitrile (1) with N-methylaniline in refluxing benzene for 20 min afforded four ring-transformed products, namely ethyl E- and Z-β-N-methylanilino-6-pyrazolo [1, 5-a] pyrimidineacrylates (8 and 9), N-pyrazolylpyrrole (10) and N-pyrazolylpyridone (11), together with 4, 7-dihydro-7-(N-methylanilino) methylpyrazolo [1, 5-a] pyrimidine (7). However, the reaction of 2 possessing a methyl group at the 5-position of 1 with N-methylaniline in refluxing xylene gave the 5-methyl derivative of 7 (13) and 5-methylpyrazolo [1, 5-a] pyrimidine (14), together with N, N-dimethylaniline. The mechanism of formation of compounds 8, 9, 10, and 11 is discussed.

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A convenient method to synthesize 1, 4-thiazane-3-carboxylic acid derivatives was established. Condensation of L-cysteine methyl ester (2a) with monochloroacetone (3a) followed by reduction with sodium borohydride yielded methyl (3R, 5S)-5-methyl-1, 4-thiazane-3-carboxylate (6a) and its (5R)-methyl isomer (7a) in a ratio of 3.1 : 1. The use of cysteine isopropyl ester (2c) instead of methyl ester (2a) gave the corresponding (5S)-methyl isomer (6e) more stereoselectively. The reaction of chloromethyl ethyl ketone (3b) or α-bromoacetophenone (3c) with 2a gave the corresponding 5-substituted-1, 4-thiazane-3-carboxylates. Hydrolysis and oxidation of 6a yielded cycloalliin (1a).

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Three new triterpene glycosides, named momordicosides C, D and E, were isolated from the seeds of Momordica charantia L. (Cucurbitaceae). Their structures were determined on the basis of spectral and chemical evidence as 3-O-β-gentiobiosides of cucurbit-5-ene-3β, 23, 24, 25-tetraol, cucurbita-5, 24-diene-3β, 22, 23-triol and 3β-hydroxy-23, 24, 25, 26, 27-pentanor-20 (ε)-cucurbit-5-en-22-al, respectively.

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In order to investigate the relationship between the position of the hydroxy group on the aromatic C-ring of dehydroabietane and the cleavage pattern upon ozonolysis, phenolic dehydroabietane derivatives having a hydroxyl group on every possible position (11-, 12-, 13-, and 14-positions) were synthesized from dehydroabietic acid (2). Friedel-Crafts acetylation of dehydroabietane (7) derived from 2 gave the 12-acetyl compound (8), which was converted to the 12-hydroxy compound (ferruginol, 10) and 11, 12-dihydroxy dehydroabietane (14). On the other hand, nitration of 7-oxo dehydroabietane (25) afforded a mixture of the 14-nitro-7-oxo compound (26) and the 13-nitro-7-oxo compound (27) in ca. 1 : 1 ratio. The former (26) was converted into 14-hydroxy dehydroabietane (32) and the latter (27) was led to both the 13-hydroxy compound (37) and the 13, 14-dihydroxy compound (47).

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Ozonolysis of phenolic dehydroabietane derivatives was investigated and the products obtained by cleavage of the aromatic ring were found to be determined by the hydroxyl substitution pattern of the aromatic C-ring. Ozonolysis of the 12-hydroxy compound (ferruginol (12)) gave pentanorlabdane-type compounds (14, 15, and 16). Ozonolysis of the 11-hydroxy derivative (18) and/or the 14-hydroxy derivatives (19 and 20) afforded optically active drimanic sesquiterpenes ((+)-isodrimenin (8), (+)-confertifolin (7), (+)-valdiviolide (9), and (+)-winterin (10)) in one step. In this case, the mode of cleavage was different from that of 12. On the other hand, ozonolysis of the 13-hydroxy compound (3) caused cleavage in yet another manner to give the butenolide (23), which was easily converted into optically active pallescensin A (11). The mechanisms of the cleavage reactions are discussed.

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14-Hydroxydehydroabietane derivatives (8 and 9), having an oxygen functional group at the 6-position, were obtained from 14-hydroxy-7-oxodehydroabietane (10) by transformation of the 7-oxo group into a 6-acetoxyl (or hydroxyl) group. Ozonolysis of the above phenols (8 and 9) and subsequent reduction gave the 6-oxygenated confertifolin derivatives 17 and 19, respectively. Oxidation of 6-hydroxyconfertifolin (19) afforded the optically active (+)-fragrolide (4). On the other hand, 19 was also converted into (+)-bemadienolide (5) by oxidation of the important intermediate, 6β-phenylselenoconfertifolin (25).

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1-Benzyl-4-[4-(2-pyridylamino)benzyl]-2, 3-dioxopiperazine derivatives, which are antitumor agents of a new type, were synthesized and the structure-activity relationships were investigated. Furthermore, the antitumor activities of 2, 3-dioxopiperazine derivatives were compared with those of 2, 5- or 2, 6-dioxopiperazines. 1-[4-(5-Amino-6-chloro-2-pyridyl)aminobenzyl]-4-benzyl-2, 3-dioxopiperazine (3a) showed excellent in vitro and in vivo antitumor activities. The compound 3a was obtained by reduction of 1-benzyl-4-[4-(5-nitro-2-pyridyl)aminobenzyl]-2, 3-dioxopiperazine (2d) with Sn-conc. HCl or SnCl₂-hydrogen chloride-MeOH. Reduction products of 2d obtained under different conditions are discussed.

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A β-keto sulfoxide (12) derived from ethyl indolebutyrate (11) and methyl methylthiomethyl sulfoxide (MMTS) was cyclized to 4-methyl-1, 1-bismethylthio-2-oxo-1, 2, 3, 4-tetrahydrocarbazole (13) by treatment with p-toluenesulfonic acid (TsOH). Introduction of an acetic ester unit at the carbonyl group with tert-butyllithioacetate gave a key intermediate (14) to all the 5-modified ellipticine analogs. An acid-catalyzed aromatization with acetic acid in xylene gave tert-butyl 4-methyl-1-methylthiocarbazole-2-acetate (15), which was readily converted to 5-methylthioellipticine (7) through a series of usual reactions. The overall yield of 7 from 11 was 25-27%. Desulfurization of 7 with Raney nickel in xylene gave 5-norellipticine (8). The bismethylthio group in 14 was easily hydrolyzed with TsOH in methanol to give a 1-keto compound (21), which was aromatized to a lactone (22), and then converted to 5-methoxyellipticine (9). Hydrolysis of 9 with 47% hydrobromic acid gave 5-hydroxyellipticine (10).

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Alkylhydroxylamines having a benzene ring in the molecule were subjected to intramolecular cyclization in trifluoroacetic acid or in the presence of Lewis acids, and benzenefused six-membered heterocycles were obtained in moderate yields from the cyclization reaction of O-acylhydroxylamines. The effect of a methoxyl group on the benzene ring was also investigated. The m-methoxy compound (1j) cyclized to give 6-methoxy-2-methyl-1, 2, 3, 4-tetrahydroquinoline (2e), while the p-methoxy compound (1k or 1l) cyclized to give the same product (2e). These unusual results could be explained in terms of a spiro-intermediate (3a).

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Irradiation of a solution of acetone and diketene in 2-propanol gave 4-(2-hydroxy-2-methylpropyl) oxetan-2-one (1) in 63% yield. 4-(2-Hydroxy-2-methylbutyl)- and 4-(2-hydroxy-2-ethylbutyl) oxetan-2-one (2 and 3) were similarly prepared. Treatment of compound 1 with hydrogen chloride in alcohol gave ethyl (E)-5-methyl-2, 4-hexadienoate (4). Ring transformation of the oxetanones (1 and 2) into pyranone derivatives was also investigated.

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Benzyl 3, 3', 4', 6'-tetra-O-benzoyl-β-di-N-acetylchitobioside (8) was prepared in 5 steps from 3, 3', 4', 6'-tetra-O-acetyl-1, 6-anhydro-β-di-N-acetylchitobiose [S. Oguri and S. Tejima, Chem. Pharm. Bull., 28, 3184 (1980)] by the following series of reactions ; de-O-acetylation, benzoylation, acetolysis of the 1, 6-anhydro-β-ring, benzyl glycosidation via oxazoline, and selective de-O-acetylation. Reaction of 8 with 2, 3, 4-tri-O-benzyl-α-L-fucopyranosyl bromide by a bromide ion-catalyzed reaction afforded benzyl 3, 3', 4', 6'-tetra-O-benzoyl-6-O-(2", 3", 4"-tri-O-benzyl-α-L-fucopyranosyl)-β-di-N-acetylchitobioside (10) in 83.4% yield. After removal of the protecting groups of 10, 6-O-α-L-fucopyranosyl-di-N-acetyl chitobiose (11) was obtained as needles. ¹³C-NMR spectra data for 11 are presented.

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Two new glucosides, named schizonepetosides A (1) and B (2), were isolated from the spikes of Schizonepeta tenuifolia (Labiatae). The structure of 1 was elucidated as (1S, 4R, 8E)-9-O-β-D-glucopyranosyl-p-menth-8 (9)-en-3-one on the basis of chemical and spectral studies. Compound 2 was identified as a glucoside possessing a dioxane ring formed by the double linkage between glucose and the aglycone, (1S, 4R, 8R)-8, 9-dihydroxy-p-menth-3-one, by X-ray crystallographic analysis.

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Twenty-two kinds of N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) analogs were synthesized and their adjuvant activity on the induction of delayed-type hypersensitivity to ABA-N-acetyl-L-tyrosine was examined. The L-alanine residue of MDP could be replaced with certain other amino acid residues without loss of activity. The structureactivity relationship of these compounds is discussed. With respect to replacement of the L-alanine residue of MDP in connection with adjuvant activity, it was shown that (1) amino acids having a suitable side chain were effective, (2) basic amino acids were unfavorable, (3) aromatic amino acids were unfavorable, and (4) acidic amino acids were effective. The D-isoglutamine residue of MDP was considered to be essential for the adjuvant activity. The adjuvant activity was decreased by esterification with methanol of the D-glutamic acid residue of MDP and related N-acetylmuramyldipeptides, but the adjuvant activity of D-glutamic acid diamide analogs was similar to that of MDP and its analogs.

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Polymers of cefsulodin sodium (CFS) formed in aqueous solution were isolated by Sephadex G-25 gel filtration and purified by dialysis in Visking tubes. Their structures were investigated chemically and by ultraviolet, infrared and nuclear magnetic resonance spectroscopy. From the results, the following polymerization process is suggested : Opening of the β-lactam ring of CFS is followed by decarboxylation, and successive cleavage of the thiazine ring results in the formation of 2-(α-sulfophenylacetamido) acetaldehyde. Aldol condensation of this aldehyde may produce polymers. The polymerization may be terminated by reaction with the isonicotinamide group of CFS. This polymerization process is different from those of penicillins previously reported by several research groups.

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The determination of some weak bases at low concentrations was investigated photometrically in non-aqueous solvents. To ensure accuracy, the chemical stoichiometric relationship between color transition of the indicator and the equivalence point was considered. The color transition of the indicator was calculated by complementary tristimulus colorimetry, which is preferable to ordinary colorimetry when dealing with several species in solution. Theoretical titration curves of titration ratio versus color transition were drawn and compared with the experimental data. It was found that 10^-2 M-10^-4 M sample solution could be determined in non-aqueous solvents.

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A sensitive fluorimetric method for the assay of catechol-O-methyltransferase in a sample solution prepared from rat liver is described. Vanillin formed from the substrate, 3, 4-dihydroxybenzaldehyde, under the optimal conditions for the enzyme reaction, is determined after the removal of unreacted substrate by adsorption on alumina. Vanillin is measured by the established fluorimetric method for the determination of aromatic aldehydes with 2, 2'-dithiobis (1-aminonaphthalene). The limit of determination for vanillin formed is 300 pmol. The method is readily performed with good precision and is suitable for the rapid assay of catechol-O-methyltransferase in a small amount of sample solution.

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Although Mycobacterium smegmatis produces carotenoids when grown in the dark, the carotenoid production of this organism is enhanced by exposure to light. This enhancement consists of an initial photochemical reaction and a series of metabolic reactions (dark reactions) which lead to the enhancement of carotenoid synthesis. Inhibition experiments with chloramphenicol showed that the dark metabolic reactions following light exposure include the process of photoinduced protein synthesis. Thus, M. smegmatis is capable of light-independent and photoinduced carotenogenesis.

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1. Diosgenin and tigogenin, which are aglycones of saponins, formed liposomes with phosphatidylcholine, and these liposomes showed a rather stable barrier function. These aglycones both have the same 3β-hydroxyl group and flat steroid nucleus as cholesterol, but have different side chains. 2. The effects of the aglycones on the phase transition of phosphatidylcholine were examined by measuring their effects on the permeability increase due to perturbation of phase equilibrium and by differential scanning calorimetry. These analogs with spirostane structure have a fluidizing effect similar to that of cholesterol. 3. The permeability increase observed in egg yolk phosphatidylcholine liposomes at 42°was not suppressed by diosgenin, suggesting that the aglycone does not have a condensing effect on phospholipid bilayers. 4. Egg yolk phosphatidylcholine liposomes with diosgenin are less sensitive to digitonin and akebia saponins than those with cholesterol.

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The present investigation was undertaken to examine the exit mechanisms of D- and L-leucine compared with those of D- and L-alanine. The exit processes of D- and L-amino acids appear to consist mainly of an unsaturable process under physiological conditions. The exit velocities of D-leucine and D-alanine were slower than those of the corresponding L-amino acid under various conditions. A marked increase in the exit velocity of L-leucine was observed in the presence of gramicidin D. This is assumed to be due to the operation of an Na⁺-dependent carrier process. On the other hand, the exit of D-leucine was not accelerated, suggesting that the exit of D-leucine is little mediated by an Na⁺-dependent process, though the influx of D-leucine was well as that of L-leucine was partly mediated by an Na⁺-dependent process.

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The interactions of sesamol (I), a monophenolic antioxidant in sesame oil, pyrocatechol (II), p-hydroquinone (III) and pyrogallol (IV) with hemoglobin A were investigated. A large excess of the phenolic (I, II and III) induced methemoglobin (MetHb) formation from oxyhemoglobin (HbO₂) at pH 7 and 25°, the rates being in the order I>II>III. The diphenolics (II and III) also reduced MetHb to deoxyhemoglobin (DeoxyHb). Pyrogallol (IV) showed a more powerful ability to produce and reduce MetHb. Sesamol (I) readily produced MetHb from HbO₂ and even from DeoxyHb, but did not reduce MetHb. MetHb formation from HbO₂ by I prevailed in the acidic range. The amount of MetHb formed by I was characteristically proportional to the concentration of HbO₂, and more than 10 equivalents of MetHb was produced at high concentrations of HbO₂. MetHb formation by I, II and III from HbO₂ was enhanced by inositol hexaphosphate, whereas MetHb formation from DeoxyHb was inhibited. The mechanisms of action of the di-and triphenolics may involve electron transfer to HbO₂ and MetHb, but that of I could not be explained analogously.

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Hog kidney mutarotase was separated into four forms (types I-IV) by DEAE-cellulose column chromatography. The most abundant form (type II) was purified to homogeneity as judged by polyacrylamide disc gel electrophoresis. The physico-chemical properties of the pure type II enzyme were as follows : molecular weight, 41000 ; isoelectric point, pH 5.48 ; K_m for α-D-glucose at pH 7.4 and at 25°, 19 mM ; optimum pH, 6.5-7.5 ; optimum temperature, 30°. The enzyme activity was greatly reduced at acid pH below 6.0. The enzyme lost little activity on storage for at least 130 days at 4°, whereas about 12% of the activity was lost during the same period at -20°. When the enzyme was heated for 10 min at 59°, the activity was completely lost.

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In order to investigate the process of percutaneous absorption of indomethacin (IND) from aqueous ethanol solution, the flux of IND was determined under various conditions by using a specially designed diffusion cell which was attached to the back of a guinea-pig. It was found that the flux of IND was governed by the initial concentration of IND, pH, the amount of ethanol in the vehicle and the amount of additive ester : the flux increased with increase in the concentrations of IND and added ester, but decreased with increase in pH and the amount of ethanol. The interactions of the components of the vehicle with IND and the skin appeared to influence the process of the percutaneous absorption of IND very strongly.

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The chemical and physicochemical stability of nifedipine in nifedipine-polyvinylpyrrolidone (PVP) coprecipitate systems was studied. It was found that nifedipine in the coprecipitate systems was chemically stable to heat and humidity. Storage of the coprecipitate systems under humid conditions was found to influence the dissolution behavior. The X-ray diffraction pattern of coprecipitate which had been stored under very humid conditions showed many sharp peaks attributable to nifedipine crystals. It is suggested that the inferior dissolution of the humidly stored coprecipitate systems resulted from the partial crystallization of amorphous nifedipine in the PVP matrix. Correlations between the in vitro dissolution behavior and the in vivo bioavailability parameters following oral administration to dogs were studied to confirm the effect of storage on the bioavailability. It was concluded that coprecipitate systems of nifedipine with PVP should be stored in such a way that they are not exposed to humidity so as to avoid a decrease of drug bioavailability.

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The metabolites of aminopyrine (AM) were analyzed by using stable isotope tracer techniques. After the oral administration of an equimolar mixture of AM and AM-2-CD₃ (mixture 1), or an equimolar mixture of AM-3-CH₂OH and AM-3-CD₂OH (mixture 2), or either AM-3-CD₃ or AM-4-N (CD₃)₂ to rats, the urinary metabolites were extracted with chloroform at pH 7.0, and the extracts were subjected to gas chromatography-mass spectrometry after trimethylsilylation. Characteristic doublet peaks in the mass spectra indicated the presence of a metabolite originating from mixture 1 or 2 mentioned above. The new metabolites detected by gas chromatography-mass spectrometry (GC-MS) were identified as 3-hydroxymethyl-4-monomethylaminoantipyrine (MAA-3-CH₂OH) and 3-hydroxymethyl-4-aminoantipyrine (AA-3-CH₂OH) from the shifts of the mass numbers of the molecular ions after the administration of AM-3-CD₃ and AM-4-N(CD₃)₂. Two other metabolites were newly detected following the administration of mixture 2(AM-3-CH₂OH is an intermediary metabolite of AM) to rats. They were identified as 3-hydroxymethyl-4-acetylaminoantipyrine (AcMAA-3-CH₂OH) and 3-hydroxymethyl-4-acetylaminoantipyrine (AcAA-3-CH₂OH). MAA-3-CH₂OH was also detected in human urine after the oral administration of AM.

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Exposure of rat erythrocytes to an O₂^- generating system of xanthine oxidase resulted in the formation of cells resistant to hypotonic hemolysis along with the degradation of hemoglobin without evidence of hemolysis. Exposure of cells for 30 min to the xanthine oxidase system caused a shift of the Soret maximum at 415 to 405 nm with the disappearance of three isosbestic points. At this time, a large amount of dark brown pigment was formed in cells and rigid cells resistant to hypotonic hemolysis were formed. Catalase but not superoxide dismutase strongly inhibited the oxidative degradation of oxyhemoglobin and the formation of resistant cells, suggesting possible involvement of H₂O₂ in the xanthine oxidase system. Moreover, cells exposed directly to H₂O₂ were transformed to resistant cells, but this did not occur in the presence of KCN. Presumably, denatured cells are produced in association with the formation of methemoglobin and denatured hemoglobin, which precipitates in the cells throughout the exposure period to H₂O₂ generated in the xanthine oxidase system.

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N-Containing activated carbon (N-CAC) was prepared by impregnating activated carbon with N-containing additives. Adsorption isotherms of hydrogen sulfide on N-CACs were obtained by a gravimetric method at 30°. A positive correlation between N content and specific adsorption of hydrogen sulfide at an equilibrium pressure of 50 Torr was found. It is considered that the adsorption of hydrogen sulfide resulted in the volume filling of micropores of N-CAC, based on application of the Dubinin-Astakhov equation to the adsorption isotherms. The finding that the net differential heat of adsorption and differential molar entropy of adsorption decreased with increasing degree of filling of micropores indicated that the micropores of N-CAC were successively filled with hydrogen sulfide from the smallest pores to the largest ones, and that hydrogen sulfide molecules were compactly filled in the micropores at an early stage of filling.

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New mesoionic heterocycles, 1, 2, 3-thiadiazolium-4-ethoxycarbonylaminides (9 and 10), were prepared by alkylation of 1, 2, 3-thiadiazoles (5) followed by treatment with base. Compound (9) was hydrolyzed to the hydrochloride of the corresponding 4-imine derivative (13), which was converted to the 4-oxo analog (16) via N-nitrosation.

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α-Ureidomethylated carboxylates were obtained by the reaction of ketene silyl acetals with benzyl N-(chloromethyl) carbamates in the presence of titanium tetrachloride. Successive hydrogenolysis over palladium-on-charcoal followed by treatment with lithium diisopropylamide gave β-lactams.

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The circular dichroism spectra of the N-2, 4-dinitrophenyl (Dnp)-derivatives of some aliphatic olefinic and acetylenic α-amino acids were examined in order to compare them with those of N-Dnp-α-amino acids with alkyl and aryl side chains. All of the L-series compounds showed negative Cotton effects of moderate strength near 400 nm. The results were explained by application of exciton chirality theory to the probable conformers. Such an explanation can also be extended to S-containing and aromatic amino acids. Thus, the results should be useful for assigning the absolute configurations of new amino acids and related amines.

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A tetradecapeptide amide, H-Ile-Asn-Leu-Lys-Ala-Ile-Ala-Ala-Leu-Ala-Lys-Lys-Leu-Leu-NH₂, corresponding to the entire amino acid sequence of a wasp venom, mastoparan M, was synthesized using the thioanisole-mediated trifluoroacetic acid deprotecting procedure.

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A sensitive spectrophotometric method for the determination of gold (III) with 5-p-dimethylaminocinnamylidene-1-phenyl-2-thiobarbituric acid (DACTB) is described. DACTB reacts easily with gold (III), forming a blue complex in diluted hydrochloric acid which can be extracted with chloroform. The chloroform solution of the complex has an absorption maximum at 622 nm against a reagent blank and shows a constant absorbance over the final hydrochloric acid concentration range of 0.02-0.07 M. Beer's law holds over the range of 0.1-0.9 μg/ml of gold (III) at 622 nm. The molar extinction coefficient of the complex is 1.1×10⁵·l·mol^-1·cm^-1. The coefficient of variation was 1.34% for 0.5 μg/ml of gold (III). The coexistence of cations such as Pd (II), Fe (II), Ce (IV), and Mn (VII) interfered considerably with the determination.

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The mutagenicity of several N-nitroso compounds, RCONHCH₂N(NO)R', which were reported as new diazoalkane-generating agents, was assayed by the Salmonella/microsome test. Among 6 amide type N-nitroso compounds which had an alkyl group at position R, only two which had a benzyl group at position R'were weakly mutagenic to Salmonella typhimurium TA100, a base-pair substitution strain, with metabolic activation by S-9 mix. On the contrary, 6 carbamate type N-nitroso compounds which had an alkoxy or benzyloxy group at position R showed considerable mutagenic activity for TA100 with metabolic activation. Two of the carbamate type compounds which had a benzyl group at position R'were also mutagenic in Salmonella typhimurium TA98, a frameshift strain, even without metabolic activation.

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Four kinds of stereoisomeric Z-Ala-Ala-OMe and eight kinds of stereoisomeric Z-Ala-Ala-Ala-OMe were tested as substrates for human spleen fibrinolytic proteinase (SFP) in comparison with porcine pancreatic elastase. Both enzymes exhibited esterase activity towards not only Z-L-Ala-L-Ala-L-Ala-OMe (VI) but also Z-D-Ala-L-Ala-L-Ala-OMe (VII). The rate of esterolysis of VI by elastase was only about twice the rate of esterolysis by SFP although the rate of amidolysis of Suc-L-Ala-L-Ala-L-Ala-pNA (XVI) by elastase was tenfold faster than that by SFP.

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Undifferentiated callus tissue of S. verbascifolium LINN. was established from sterilized seeds on Murashige and Skoog's revised medium and maintained on the same medium. Six-month-old callus was then analyzed for steroidal sapogenins and glycoalkaloids. Diosgenin and solasodine were isolated and estimated quantitatively in tissue samples harvested periodically (2, 4, 6 and 8 weeks).

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The stability of tryptophan in aqueous solutions of HCl, H₂SO₄, or CH₃SO₃H under aerobic conditions was examined, and a specific effect of HCl was found. A kinetic study of the HCl-induced decomposition, tests for the free chlorine formation on heating the HCl used for the above run, etc. suggested that free chlorine produced by the air oxidation of HCl may hace participated in the decomposition of tryptophan. Thin-layer and ion-exchange chromatography of the decomposition products of tryptophan revealed that oxindolylalanine and dioxindolylalanine were formed by the reaction. These two compounds were also formed by treating tryptophan with ClO^- or N-chlorosuccinimide in a solution of HCl. These results support the above possibility.

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Difference of anodic oxidation potentials of hydroxamic acid between those in the absence and presence of a base depends on the strength of hydrogen-bonding between the acidic proton and base, being a measure of hydrogen-bonding and relative basicity of the base in the medium.

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A mixture of diethyl phosphorocyanidate (DEPC) and hydrogen peroxide in the presence of 2-hydroxypyridine or 1, 2, 4-triazole functions as an epoxidizing agent for olefins.

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Acacetin, tilianine, and new glucosylflavones, isoagastachoside (2"-O-acetyl tilianine) and agastachin (di-6"-tilianine malonate), were isolated from the aerial part of Agastache rugosa (Labiatae). These structures were confirmed by the various spectroscopic evidences.

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Monothiazolization of ethyl 2-methyl-1, 3-dioxo-2-cyclohexaneacetate (I) afforded 2-aminothiazole derivative (IIa) corresponding to tetralone. In several steps, IIa was converted to some thiazolo [4, 5-f] morphans (X) via 9-oxothiazolo [4, 5-f] morphan (VIII).

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Geosmin, an earthy-musty smelling compound, and 2-phenylethanol were detected by gas chromatography and mass spectrometry combined with gas chromatography from the volatile metabolites of Chaetomium globosum KINZE ex FR., a fungus isolated from the soil at Sugadaira, Nagano Prefecture. It was suggested that fungi are partly responsible for the unpleasant earthy-musty odor and taste in public water supplies.

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Highly purified hog pancreatic kallikreins A and B from the autolysed hog pancreas were digested with pronase and subjected to hydrazinolysis to release asparagine-linked sugar chains. The oligosaccharides released were separated into fractions based on the acidities due to the contents of neuraminic acid residues. Out of these oligosaccharides, fractions having no neuraminic acid obtained from both A and B were further separated according to the molecular size by the 2 times repeated gel filtrations and their carbohydrate contents were analysed. Thus varied primary structures of carbohydrate chains-namely, different number of neuraminic acid residues being bound, straight and branched oligosaccharide chains, and the high mannose containing and the complex carbohydrates containing structures-of these asparagine-linked oligosaccharides being consisted parts of hog pancreatic kallikreins were observed.

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Vineomycin A₁ (formerly OS-4742 A₁) produced by Streptomyces matensis subsp. vineus, is an antibacterial and antitumor antibiotic. The aglycon part obtained by mild hydrolysis turned out to be identical with aquayamycin, and its ¹³C-NMR assignment was also determined.

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The new pungent principles, γ-sanshool and hydroxy γ-sanshool, were isolated from the pericarps of Zanthoxylum ailanthoides SIEB. et ZUCC. Their structures were determined as (2E, 4E, 8Z, 10E, 12E)-N-isobutyl-2, 4, 8, 10, 12-tetradecapentaenamide and (2E, 4E, 8Z, 10E, 12E)-2'-hydroxy-N-isobutyl-2, 4, 8, 10, 12-tetradecapentaenamide by chemical and spectroscopic evidences.

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