The oxidation of 2-methylnaphthalene to 2-methyl-1, 4-naphthoquinone (vitamin K₃) was carried out with aqueous (60%) H₂O₂ in acetic acid in the presence of Pd(II) salts at 50°C. The activities of Pd(II) salts were in the order of SO^2-₄>ClO^-₄>NO^-₃>AcO^->PO^3-₄>Cl^->Br^->I^-. The Pd(II) salts such as PdSO₄, Pd(ClO₄)₂, Pd(AcO)₂, and PdCl₂ were heterogenized by ion exchange between Pd(II) ion and protons of sulfonated polystyrene-type resin (SP resin) to give Pd(II)-SP resin. The use of 0.24% Pd(II)-SP resins gave a good yield (50 to 60%) of vitamin K₃ at 50°C. The catalyst could be recovered by filtration and reused conveniently.

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The hydroalkylation of phenol (1) in the presence of palladium catalyst and fused salt (NaCl-AlCl₃) under hydrogen pressure was carried out. By using 1% Pd-Al₂O₃ (1 g) and the fused salt (1 : 1 mol ratio, 6 g), 4-cyclohexylphenol (6) was obtained selectively from 1 (30 g) in a yield of 31.9% at 120°C for 4.5 h. Cyclohexylphenols were formed by way of 2-cyclohexen-1-ol and 1.

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The surface properties of prostaglandins F_2a, E₂, D₂, A₂ and B₂ at the air-water interface were studied under conditions where these compounds are stable. Our values of critical micelle concentrations (cmc) of prostaglandins F_2a, E₂, A₂ and B₂ at pH 7.80 were 2.7×10^-2, 1.3×10^-2, 8.8×10^-3 and 6.2 ×10^-3 mol·dm^-3, respectively, whereas the formation of micelles at pH 4.96 was not detected for any of the prostaglandins tested. The cmc for prostaglandin D₂ could not be determined due to the instability of the compound at pH 7.80. However, the surface behavior of prostaglandin D₂ at pH 4.96 was very similar to that of prostaglandin E₂, indicating that prostaglandin D₂ may have a value of cmc at pH 7.80 close to that of prostaglandin E₂. These values of prostaglandins are comparable to those of sodium decyl sulfate, dodecanoic acid and tetradecyl phosphate. Possible structures of prostaglandins at the air-water interface and probable mechanisms of membrane penetration and permeation are discussed.

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β-Arylaminocrotonaldehydes (3) were prepared by alkaline hydrolysis of 1-arylamino-3-arylimino-1-butenes (2). On treatment with sulfuric acid, β-anilinocrotonaldehyde (3b) and p-methyl- (3a), m-chloro- (3c), and p-chloro- (3d) derivatives were cyclodehydrated to give the corresponding quinaldines in quantitative yields. The protonation of 3 was proved to take place at the oxygen atom on the basis of spectral evidence.The mechanism of the cyclodehydration is discussed.

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Reaction of 2', 3'-di- or 2', 3', 5'-tri-O-protected guanosine (I, IX) with phosphorus trichloride in ethyl methyl ketone, cyclohexanone or benzaldehyde afforded the corresponding N²-(1-phosphono)alkylguanosine derivative (IIa-c). The structure of the aglycon (IIIa) was determined definitely by the X-ray diffraction method. A similar reaction in dioxane resulted in no modification of the guanine moiety, while the reaction in tetrahydrofuran gave 4-(inosin-2-yl)amino-4-phosphonobutyl hydrogen phosphonate (VII). None of the reactions in acetylacetone, benzoquinone, naphthoquinone and anthraquinone modified the guanine base. An alternative preparation of guanosine 5'-monophosphate was accomplished by the reaction of isopropylideneguanosine(IX) with phosphorus trichloride in anthraquinone in a stream of oxygen, followed by hydrolysis and deblocking.

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The reaction of (S)-3-4'-isopropyl-1'-3'-oxazolidino-1-phenylpropan-1-ones (1a, 1b) with 4 mol eq of various organotitanium triisopropoxides in ether at room temperature for 18-20 h gave 1-alkyl(or aryl)-3-N-alkyl(or arymethyl)-N-1'-isopropyl-2'-hydroxyethylamino-1-phenyl-propan-1-ols (2a-h) in good yields.This 1, 5-asymmetric induction proceeded with extremely high diastereoselectivity. The absolute configurations of 2d and 3d were determined by X-ray analysis.

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Reactions of aliphatic, aromatic and heterocyclic thiols (2 and 5a-h) with diethyl bromomalonate (1a) gave the corresponding symmetrical disulfides (3 and 6a-h) in high yields. In the case of L-cysteine (5i), glutathione (5j) or thiamine (5k), the reaction also gave L-cystine (6i), oxidized glutathione (6j) or thiamine disulfide (6k) in high yields regardless of the presence of other functional groups. Dithiols (11) were converted into cyclic disulfides (12) by this method. In particular, N-(2-mercapto-2-methylpropionyl)-L-cysteine (9) was converted into (4R)-tetrahydro-7, 7-dimethyl-6-oxo-3H-1, 2, 5-dithiazepine-4-carboxylic acid (10)(obtained in poor yields by general oxidation methods) in good yield. The intermediate in the reaction was considered to be sulfenyl bromide (8).

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A quantitative analytical study to determine the isomer ratios of the 6-piperidones (type 7) and 2-piperidones (type 5) produced by the mercuric acetate-edetic acid (EDTA) oxidation of 1-(2-aryl-2-hydroxyethyl)-3-alkylpiperidines (±)-4c, d, f, h, 4e, g, i, j, and (±)-38 was carried out. It has been found that all the substrates with a benzyloxy group in the aryl moiety, regardless of its location, undergo oxidation at the 6-position preferentially as compared with the debenzyloxy derivatives such as (±)-4a, b. Comparison of the quantitative data from 4e and (±)-4f with those from (±)-4b indicated that the cis acetate chain at the 4-position increases the extent of the 6-oxidation, whereas a trans acetate chain at the same position has little effect. These two factors enhance the practical value of the "cincholoipon-incorporating method" for chiral syntheses of the 1-type Alangium alkaloids, in which the mercuric acetate-EDTA oxidation of 4e, g, i, j to the 6-piperidones (type 3)is one of the key synthetic operations.

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Cyclic voltammetry of 2, 6-di-tert-butyl-4-methyphenol (1) in acetonitrile in the presence of an aliphatic amine such as ethyl-, diethyl-, or triethylamine shows an ill-defined anodic wave-a socalled kinetic wave-around 0.5 V vs. aqueous saturated calomel electrode, indicating an electron-transfer process preceded by a slow chemical reaction. Based on the estimated pK_a value of 1 (pK_a=12.55 in water at 25°C), the chemical reaction was ascribed to a slow hydrogen-bonding association of 1 and the added amine. Controlled potential electrolysis of 1 at the potential of the anodic wave gave an unsymmetrical dimer, 2, 6-di-tert-butyl-4-(3, 5-di-tert-butyl-4-hydroxyphenyl)-4-methyl-2, 5-cyclohexadiene-1-one, as the main product. Side-chain aminated derivatives of 1, Ar-CH₂NHEt, Ar-CH₂NEt₂, and Ar-CH₂N⁺NEt₃ (Ar=3, 5-di-tert-butyl-4-hydroxyphenyl), are suggested to be the intermediates; that is, the process of dimer formation is explained in terms of cross-coupling of the phenoxyl radicals derived from 1 and the side-chain aminated phenols followed by expulsion of the aminomethyl group.

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The reactions of 2-benzamido(and acetamido)-3-cyano-4, 5-dihydrothiophenes (Ia and Id) with ethyl cyanoacetate or malononitrile gave ethyl α-cyano-4-[2-phenyl(and methyl)-5, 6-dihydrothieno-[2, 3-d]pyrimidine]acetates (IIa-1 and IId-1) or 4-[2-phenyl(and methyl)-5, 6-dihydrothieno[2, 3-d]pyrimidine]malononitriles (IIa-2 and IId-2). Similarly, 2-benzamido(and acetamido)-3-cyano-5-methyl(or 4-phenyl)-4, 5-dihydrothiophenes (Ib, e or Ic, f) reacted with ethyl cyanoacetate or malononitrile to form the corresponding ethyl cyanoacetate derivatives (IIb, c-1, IIe, f-1) or malononitrile derivatives (IIb, c-2, IIe, f-2). Compounds IIa-f-1 and IIa-f-2 were prepared by the reactions of the corresponding 4-chloro-5, 6-dihydrothieno[2, 3-d]pyrimidines and ethyl cyanoacetate or malononitrile.

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A new lignan glycoside was isolated from the bark of Eucommia ulmoides OLIV. (Eucommiaceae) and its structure was established as (+)-1-hydroxypinoresinol 4"-O-β-D-glucopyranoside (1) on the basis of chemical evidence and spectroscopic studies. An isomer of 1, (+)-1-hydroxypinoresinol 4'-O-β-D-glucopyranoside (2), was also isolated, together with (±)-erythro-, and (±)-threo-guaiacylglycerol (3 and 4), (+)-cyclo-olivil (5) and (-)-olivil (6).

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A new porcine gastrointestinal 29-residue peptide, galanin, was synthesized in a satisfactory yield by assembling seven peptide fragments followed by deprotection with 1 M trifluoromethane-sulfonic acid-thioanisole in trifluoroacetic acid. Nⁱⁿ-Mesitylenesulfonyltryptophan was employed to suppress indole alkylation during N^a-deprotection. β-Cycloheptylaspartate was employed to suppress base-catalyzed succinimide formation. The synthetic peptide exhibited a powerful contractile activity on rat ileum, but not on guinea pig ileum and caused sustained hyperglycemia in dogs.

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A novel method for the introduction of a methyl group into aromatic rings in described. Friedel-Crafts reactions of ethyl α-(chloromethylthio)acetate (3k) and α-chloromethylthio-γ-butyrolactone (3m) with an arene in the presence of stannic chloride gave ethyl α-(arylmethylthio)-acetate (6) and α-arylmethylthio-γ-butyrolactone (7), respectively, which were easily converted to the corresponding methylated arene (8) by reductive desulfurization with Raney nickel or zinc dust-acetic acid.

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Prostanoic acid (18) and 8-isoprostanoic acid (1) constitute the basic structures of primary prostaglandins and 8-isoprostaglandins. The conversion of commercially available (+)- and (-)-limonene to these compounds was accomplilshed by a sequence of reactions involving the Rh(I)-catalyzed cyclization of 3, 4-disubstituted 4-pentenals, which were easily prepared from (+)- or (-)-limonene, to cis-3, 4-disubstituted cyclopentanones and the appropriate modification of substituents on the five-membered ring.

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The paramagnetic species formed by in situ electrochemical oxidation of N-(2-nitrophenyl-thio)dibenzylamine (1) and three N-methyl-4'-substituted 2-nitrobenzenesulfenanilides (4'-CH₃ (2), 4'-C(CH₃)₃ (3), 4'-COOC₂H₅ (4)) have been identified as the radical cations derived from the parent sulfenamides by one-electron transfer. On the other hand, the radicals generated from three 4'-unsubstituted N-alkyl-2-nitrobenzenesulfenanilides (N-CH₃ (5), N-C₂H₅ (6), N-CH₂C₆H₅ (7))have been identified as the radical cations of N, N-dialkyl-diphenoquinone-diimines formed by dimerization of the sulfenanilide radical cations and further oxidation of the dimers. From the voltammetric data, it is proposed that the dimerization takes place before the cleavage of the S-N bond in the sulfenanilide radical cations.

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The reactions of (E)-methyl 1-oxido-2-quinolyl ketone oxime (V_E), (E)- and (Z)-methyl 1-oxido-4-quinolyl ketone oxide (VII_E and VII_Z) and (Z)-methyl 2-oxido-1-isoquinolyl ketone oxime (IX_Z) with tosyl chloride in the presence of NaOH were investigated to compare the reactivity of the N-oxide with that of the oxime group in the same molecule. In the reaction of V_E, 1-hydroxy-2-(1H)-quinolinone (XII) and 2(1H)-quinolinone (XIII) were obtained by the elimination of the acetoxime group. The mechanism of the formation of XII and XIII is discussed in detail. In the reaction of VII_E, Beckmann rearrangement occurred to afford 4-acetylaminoquinoline 1-oxide(XVIII), while the reactions of VII_Z and IX_Z gave only the tosylates of the oximes. These results demonstrate that there is a large difference of reactivity between the E-form and the Z-form, and further that V_E and VII_E show markedly different chemical behavior.

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A series of 1 : 2 cycloadducts of a new type was obtained from the reaction of 2-alkylpyridine N-oxides with phenyl isocyanates. The reaction mechanisms are discussed in terms of frontier molecular orbital theory based on CNDO/2 and MINDO/2 calculations and kinetic data. The small solvent effect and activation parameters (E_a=14 kcal/mol, ΔS=-46 e.u.) observed for the reaction of 2-alkylpyridine N-oxides with phenyl isocyanates indicate that the cycloaddition proceeds via concerted pathways involving little charge separation in the transition state.

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A new triterpenol xyloside, beesioside II (2), mp 149-151°C, [α]_D +9.3°, C₃₉H₆₂O<12>·0.5H₂O, from the dried rhizomes of Beesia calthaefolia MAXIM. (Ranunculaceae), was identified as(20S, 24R)-16β, 18-diacetoxy-20, 24-epoxy-9, 19-cyclolanostane-3β, 15α, 25-triol 3-O-β-D-xylopyranoside on the basis of chemical and physicochemical evidence. The structure of 2 was confirmed by an X-ray structure analysis of a derivative.

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The reaction of 2-amino-3-cyano-4, 5-dihydrofuran (Ia) with benzoyl(or acetyl) chloride in the presence of sodium hydride and sodium hydrogen carbonate gave 2-benzoyloxy(or acetoxy)ethyl-malononitrile (IIa or IIIa). Similarly, 2-amino-3-cyano-5-methyl-4, 5-dihydrofuran (Ib) and 2-amino-3-cyano-4-phenyl(or 5-phenyl)-4, 5-dihydrofuran (Ic or Id) reacted with benzol(or acetyl)-chloride to form the corresponding malononitrile derivatives (IIb-d or IIIb-d). On the other hand, the reaction of Ia with phenacyl bromide gave 3-cyano-2-imino-3-phenacyltetrahydrofuran (IV).

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Three new flavans, daphnodorin A(1), daphnodorin B(2) and daphnodorin C(3), as well as four known coumarins, daphnetin, daphnoretin, umbelliferone and daphneticin, were isolated from the root and the bark of Daphne odora THUNB. The plane structures of 1 and 2 were established by chemical and spectroscopic means.

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Seven peptide fragments were synthesized by known amide-forming reactions as building blocks for the solution-phase synthesis of the heptatriacontapeptide amide corresponding to the entire amino acid sequence of human calcitonin gene-related peptide (hCGRP). S-1-Adamantyl-cysteine [O. Nishimura, C. Kitada, and M. Fujino, Chem. Pharm. Bull., 26, 1576 (1978)] was employed, together with amino acid derivatives bearing protecting groups removable by 1 M trifluoromethanesulfonic acid-thioanisole in trifluoroacetic acid.

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The heptatriacontapeptide amide corresponding to the entire amino acid sequence of human calcitonin gene-related peptide (hCGRP) was synthesized by assembling seven peptide fragments in solution, followed by deprotection with 1 M trifluoromethanesulfonic acid-thioanisole in trifluoroacetic acid and subsequent air-oxidation to establish the disulfide bridge. The S-1-adamantyl group of the Cys residue was removed in two ways; one was by treatment with the above acid, together with the other protecting groups employed, and the other was selectively by treatment with(CF₃COO)₃Tl. The synthetic peptide produced a significant increase of cyclic adenosine monophosphate in calvaria and brain of a newborn rat, but suppressed ⁴⁵Ca-release from mouse calvaria stimulated by parathyroid hormone.

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Cycloaddition of formylketene generated in situ by thermolysis of 2, 2-dimethyl-1, 3-dioxin-4-one with N-benzhydrylidenebenzylamine yields 3-benzyl-2, 2-diphenyl-1, 3-oxazin-4-one. Analogous reactions with a carbodiimide, cyanamide, and keteneacetal afford the corresponding 4+2 cycloadducts. Reaction of formylketene with 3-amino-2-butenamides affords 4-hydroxy-2-pyridones having a C-2 unit at the 3-position.

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Daphnetin (3) was transformed with excess benzyl chloride into 7, 8-dibenzyloxycoumarin (4), which on treatment with trifluoroacetic acid in benzene or aluminum chloride in benzene gave 8-benzyloxy-7-hydroxycoumarin (5) in good yield. Condensation of 5 and ethyl 2-bromo-3-(4-acetoxy-3, 5-dimethoxyphenyl)-3-oxopropionate (9), prepared from ethyl benzylsyringoylacetate (7) in two steps, in the presence of sodium hydride afforded 10 in good yield, and the condensation product (10) was then reduced with lithium borohydride to yield a mixture of the diols (11a, b). Treatment of the diols with 36% hydrochloric acid in acetic acid provided daphneticin (1) in 68% yield.

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A chemical examination of the bark of Cinnamomum cassia( ?? ?? ?? ?? : Lauraceae) has led to the isolation of three flavan-3-ol glucosides (1-3) and three oligomeric procyanidins (4-6) named cinnamtannins A₂-A₄, together with (-)-epicatechin(7), procyanidins B-2 (8), B-5 (9) and C-1 (11), and a doubly-linked proanthocyanidin (10). On the basis of chemical and spectroscopic evidence, compounds 1-3 were characterized as (-)-epicatechin 3-O-, 8-C- and 6-C-β-D-glucopyranosides, respectively, while compounds 4-6 were shown to be tetrameric, pentameric and hexameric procyanidins, respectively, consisting exclusively of (-)-epicatechin units linked linearly through C(4β)-C(8) bonds.

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Along with procyanidins B-1 (4), B-2 (5), B-5 (6) and B-7 (7), and the doubly linked proanthocyanidin, A-2 (8), two new procyanidin glucosides have been isolated from the bark of Cinnamomum cassia BLUME( ?? ?? ?? ?? )(Lauraceae), and characterized as procyanidin B-2 8-C- and 6-C-β-D-glucopyranosides (1 and 2, respectively) on the basis of proton and carbon-13 nuclear magnetic resonance examinations and the results of thiolytic degradation. In addition, from the bark of Cinnamomum obtusifolium NEES( ?? ?? ?? ?? ?? ?? ), an acylated flavan-3-ol glucoside (3) has been isolated, together with the known proanthocyanidins B-1 (4), B-2 (5), B-5 (6) and A-2 (8). The structure of 3 has been established to be (+)-catechin 5-O-β-D-(2"-O-feruloyl-6"-O-p-coumaroyl)-glucopyranoside on the basis of chemical and spectral evidence.

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The structures of punicalin and punicalagin, isolated from the bark of Punica granatum L. (pomegranate), have been revised to 4, 6-(S, S)-gallagyl-D-glucose (1) and 2, 3-(S)-hexahydroxy-diphenoyl-4, 6-(S, S)-gallagyl-D-glucose (2), respectively, on the basis of chemical and spectroscopic evidence. In addition, a new hydrolyzable tannin, 2-O-galloyl-4, 6-(S, S)-gallagyl-D-glucose (3) was isolated from the same plant source, and characterized.

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A chemical examination of the bark of Punica granatum L. (Punicaceae) has led to the isolation of five new ellagitannins, punicacorteins A, B, C and D, and punigluconin, together with the known ellagitannins, casuariin (6) and casuarinin (7). Based on chemical and spectroscopic evidence, the structures of punicacorteins A, B, C and D were established as novel C-glycosideic ellagitannins, the former two possessing a unique tetraphenyl (gallagyl) ester group (1 and 2), and the latter two containing a galloyl group in place of the gallagyl group (3 and 4), while punigluconin was characterized as 2, 3-di-O-galloyl-4, 6-(S)-hexahydroxydiphenoylgluconic acid (5).

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Upon treatment with benzylamine and n-propylamine, 10-thiaisoalloxazines 3 undergo a smooth ring-contraction initiated by nucleophilic addition of alkyl amines to the conjugated diimine bond in the molecule to give the corresponding 6'-substituted amino-spiro[benzothiazoline-2, 5'-pyrimidine-2', 4'(3'H, 5'H)-diones] 4, whereas thermal reaction of 3 with benzyl alcohol results in the preferential formation of the redox products, 1, 5-dihydro-10-thiaisoalloxazines (cf. 6) and benzaldehyde, proceeding via an initial one-electron transfer process.

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A formal chiral synthesis of the Alangium alkaloid (-)-ankorine [(-)-6] has been accomplished in the form of the synthesis of the lactam phenol (+)-14 from the (+)-trans-lactim ether (+)-5 and 2-benzyloxy-3, 4-dimethoxyphenacyl bromide through the intermediates (+)-10 and 11. A parallel sequence of conversions starting from the (-)-trans-lactim ether (-)-5 and proceeding through the intermediates (-)-10, 24, (-)-14, (-)-15, 26, (+)-27, and (+)-28 produced the enantiomer [(+)-6] of natural ankorine. For an alternative chial synthesis of (-)-6, ethyl cincholoiponate [(+)-19] was acetylated and the resulting N-acetyl derivative (+)-20-was oxidized with RuO₄ to give the 6-piperidone (+)-21, and 2-piperidone (-)-23 in 55% and 27% yields, respectively. The (-)-cis-lactim ether (-)-16, obtained by ethylation of (+)-21 with triethyl-oxonium fluoroborate, was then converted into (-)-13, a known precursor for the synthesis of (-)-ankorine [(-)-6], in good overall yield by a "lactim ether route, " which proceeded through (+)-15 and 12.

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The first syntheses of 1-methoxy analogs of ergot alkaloids, (±)-1-methoxy-6, 7-secoagroclavine and (±)1-methoxy-6-nor-6, 7-secoagroclavine, were achieved with good overall yield in only nine steps from 2-nitrotoluene.

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Many (1-piperazinylcarbonyl)-2(1H)-quinolinone derivatives were synthesized and examined for positive inotropic activity on the canine heart. Among them, 3, 4-dihydro-6-[4-(3-oxo-3-phenylpropyl)-1-piperazinylcarbonyl]-2(1H)-quinolinone (XXIj) and 3, 4-dihydro-6-[4-(oxo-4-phenylbutyl)-1-piperazinylcarbonyl]-2(1H)-quinolinone (XXIl) were found to have potent activity.

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Conformational analysis of the minimum active unit of gastrin, tetragastrin (Trp-Met-Asp-Phe-NH₂), led to the formulation of common hypothetical receptor binding moieties with 5, 1-benzothiazocines, these moieties being a benzene ring, a nonbasic nitrogen and a hydrophobic group. A molecular mechanics calculation study of tetragastrin was carried out in an attempt to find a stereochemical correlation with a representative 5, 1-benzothiazocine, RS-2039, which had been structurally elucidated by X-ray crystallographic analysis. Several stable conformers of tetragastrin were discovered to have a close approximation of the 3-dimensional array of receptor binding moieties to that of RS-2039. It has thus been theoretically demonstrated that gastrins and 5, 1-benzothiazocines could bind with an identical receptor.

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2-Acetylthio-3-(4-substituted phenoxybenzoyl)propionic acids and various other ω-(4-phenoxybenzoyl)alkanoic acid derivatives were prepared, and tested for hypolipidemic activity in normal rats. Some of these compounds were active. 2-Acetylthio-3-(4-phenoxybenzoyl)propionic acid derivatives seemed to have the most potent hypocholesterolemic activities, and halogen substitution on the phenoxy group increased the activity.

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A series of 5-fluoro-t-4-[(Z)- and (E)-furfurylideneaminooxy]hexahydro-2, 6-dioxor-5-pyrimidinecarboxylates (6 and 7) was prepared by treatment of the corresponding 4-acetoxyhexa-hydropyrimidinecarboxylates 5 with (Z)- and (E)-furfuraldoximes (10 and 11), respectively, and tested for antitumor activity against murine colon carcinoma 26. The oxime ether 7c (TAC-788) showed antitumor activity against various murine tumors.

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Hydrolyzable tannins from crude drugs were examined for inhibitory activity against glucosyltransferase from a cariogenic bacterium, Streptococcus mutans. Pentagalloylglucose showed a strong inhibitory effect, whereas ellagitannins stimulated the glucan synthesis in 10% ethanol. All the gallotannins were more potent than chlorhexidine gluconate in an aqueous reaction mixture. Among them, penta- and hexagalloylglucose were the most potent, being inhibitory at a concentration of 10^-3M. The inhibitory character of gallotannins depended on the number of galloyl residues.

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Thalictoside (1), a novel glycoside containing a nitro group, was isolated from Thalictrum aquilegifolium and the structure was shown to be 4-hydroxy-1-(2-nitroethyl)benzene 4-O-β-D-glucopyranoside on the basis of chemical transformations, spectral analysis and synthesis. Several known compounds were also isolated.

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Saponins of plants of wild Panax species (Araliaceae), collected at Chame and Ghorapani in central Nepal and designated as a subspecies or a variety of P. pseudo-ginseng, were investigated. From rhizomes of the specimen collected at Chame, the known dammarane-saponins, ginsenosides-Rg₁ (1), -Re (2), -Rb₁ (4), -Rb₃ (5), -Rd (6) and gypenoside XVII (7) were isolated together with two new saponins, 24(S)-pseudo-ginsenoside F₁₁ (3) and monoacetyl-ginsenoside-Rd (8; named pseudo-ginsenoside-RC₁). From rhizomes of the specimen collected at Ghorapanai, 1-7, notogin-senoside-R1 (11), quinquenoside-R₁ (12), majonoside-R2 (13) and malonyl-ginsenoside-Rb₁ (14)were isolated, No saponin of oleanolic acid (16) was detected in either of the specimens. The specimens of the present study have a horizontally elongated rhizome, being morphologically similar to the Panax spp. which distributed from Bhutan in the Eastern Himalaya (P. pseudo-ginseng subsp. himalaicus) to Japan through the South-West province of China, the rhizomes of which contain a large amount of the common saponins of 16 along with the dammarane saponins. It is chemotaxonomically and pharmacognostically significant that the saponin composition of the specimens of the present study is evidently different from that of these plants, being rather similar to that of roots of P. ginseng, P. quinquefolium and P. notoginseng whose big carrot-like roots contain a number of physiologically active dammarane saponins with only trace levels or none of the saponin of 16.

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A new spectrophotometric method for the determination of small amounts of chlorine ion by using 1, 5-bis(6-methyl-4-pyrimidyl)carbazone (MPC) has been established.The proposed method is based on the reduction of the absorbance of silver-MPC complex at 530 nm after the reaction of chlorine ion with the complex to form AgCl in 1 M ethanolic acetic acid solution. Silver-MPC is a violet complex (λ_max=530 nm) which is soluble in water, pyridine, dimethylsulfoxide and lower alcohols, and is stable when kept in light-resistant containers. A surfactant was added to the solvent to disperse silver chloride colloid uniformly in the test solution, and this allowed direct measurement of absorbance without the separation of AgCl. The calibration curve conformed to Beer's law between 1×10^-5 and 1×10^-4 M chlorine ion.This method could be applied to the determination of various chlorine-containing organic compounds listed in The Japanese Pharmacopoeia (JPX), when they were processed by the oxygen flask combustion method described in the General Test Methods of JPX.

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A simple and highly sensitive method for the determination of serum albumin based on the formation of a ternary complex from chrome-azurol S aluminium chelate was developed. A nonionic detergent, polyethylene glycol-p-nonylphenyl ether n=10, acted as a stabilizer of the ternary complex in the present system. The formation of the ternary complex caused a large increase in absorbance at 630 nm, and the calibration curve was linear between 10 and 200 μg of albumin in the final colored solution (8.0 ml). The sensitivity of the present method was about eight times that of a bromcresol green control method. Heparin and bilirubin did not interfere with the determination.

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Genetic control of carotenoid synthesis in Mycobacterium smegmatis (M. smegmatis), which produces carotenoids both photoinducibly and constitutively, was investigated in several strains of M. smegmatis by using a multi-polar conjugation system. The analysis of the recombinants revealed that the amount of carotenoids produced was strain specific, and the photoinduced and constitutive carotenoid syntheses were under the same genetic control. At least 3 genes participate in the genetic control of carotenoid synthesis in M. smegmatis. Constitutive carotenoid synthesis of M. smegmatis is a result of an incomplete repression of carotenoid gene.

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The effect of light on the pigmentation of various strains of Micromonospora, Microbispora and Actinoplanes was investigated. It was found that four of eight strains of Micromonospora, two of five strains of Microbispora and two of three strains of Actinoplanes were photochromogenic. These photochromogenic strains produced carotenoids by photoinduction. Biochemical studies on the mechanism of photochromogenicity in Micromonospora echinospora, Microbispora chromogenes and Actinoplanes philippinensis showed that photoinduced carotenoid synthesis in these strains consists of an initial temperature-independent photochemical reaction step and a series of dark metabolic reaction steps, which involve de novo protein synthesis.

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L-Phenylalanine was administered intraperitoneally, intravenously, intramuscularly and orally to rats, and its metabolites were separated and identified by high-performance liquid chromatography (HPLC) with fluorescence detection. Chromatographic peaks were identified on the basis of their retention behavior and the assignment of peaks of HPLC was verified by ion-exchange chromatographic analysis. The three metabolites p-, m- and o-tyrosines were formed in vivo after phenylalanine administration. The extents of formation of m- and o-tyrosines were significantly increased by the administration of L-phenylalanine. However, the concentrations of m- and o-tyrosines in the serum were reduced by the administration of α-methyltyrosine, which is an inhibitor of tyrosine hydroxylase. On the other hand, the inhibition of phenylalanine hydroxylase activity by the administration of p-chlorophenylalanine and ethionine resulted in a marked increase of the concentration of phenylalanine in the serum, and the formation of m- and o-tyrosines was also significantly increased. These results suggest that the formation of m- and o-tyrosines from phenylalanine is caused mainly by tyrosine hydroxylase, but not by phenylalanine hydroxylase.

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The mutagenicities of methyl, ethyl, isopropyl, and butyl methanesulfonates and the corresponding alkyl derivatives of N-nitrosoureas were examined using E. coli B Hs30R tester strain deficient in the excision deoxyribonucleic acid-repair system. Their mutagenic capacities were standardized by converting the experimentally obtained mutation frequencies into those per unit of the concentration-time integrated dose with various dimensions, μM·h, mM·h, and M·h. The mutation frequencies under various conceptual exposure conditions were computed by using those at unit integrated dose, on the assumption that the dose-response relation is linear on a log-log scale. The results indicate that the relative mutagenic capacities of these alkylating agents were strongly dependent on the measure (dimensions) of the mutagenic capacities computed in the present study. Consequently, care is necessary in the quantitative evaluation of mutagenicity, especially when the dose-response relation is not linear but exponential.

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Human erythrocyte ghosts modified with 13-hydroperoxylinoleic acid (LOOH) and the secondary degradation products of peroxidized lipids, i.e. malonaldehyde (MDA) and monofunctional aldehydes, were analyzed for fluorescence formation and protein cross-linking. Reaction of ghosts with LOOH produced fluorescent ghost proteins with an excitation maximum at 357 nm and an emission maximum at 438 nm. The MDA-modified ghost proteins exhibited fluorescence spectra with a longer maximum wavelength, an excitation maximum at 398 nm and an emission maximum at 467 nm, whereas the fluorescence spectra of the ghost proteins modified with 1-heptanal and 2, 4-decadienal were indistinguishable from those observed for LOOH-modified ghost proteins. Similar results were obtained for lipid extracts of the modified ghosts. Like LOOH and MDA, the monofunctional aldehydes such as 1-hexanal, 1-heptanal and 2, 4-decadienal were capable of cross-linking the ghost proteins as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The importance of MDA in the formation of fluorescence and cross-links may have been exaggerated in earlier reports.

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Type IV collagen was purified from the pepsin digest of mouse kidneys by heat-gelation and column chromatography on dimethylaminoethyl (DEAE)- and carboxymethyl-cellulose under nondenaturing conditions. The mouse type IV collagen was separated into two fractions on DEAE-cellulose, one (type IV collagen-1) non-adsorbed and the other (type IV collagen-2) adsorbed on the column, although both gave similar results in amino acid analysis.Indirect immunofluorescence using rabbit antiserum against the purified collagen revealed specific localization of the collagenous protein in the basement membrane of both mouse and human kidneys. This fundings strongly suggests that the basement membrane collagens of both species share certain antigenic determinants. In dodium sodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) without 2-mercaptoethanol (2-ME), both type IV collagen-1 and -2 migrated poorly into the 5% separating gel, suggesting high molecular weight. After reduction with 2-ME, the proteins penetrated better into the gel and were resolved into three major components with apparent molecular weights of 150000, 135000 and 90000, though slight differences were found in the ratios of these polypeptides and minor peptides. In addition, the purified collagen preparations were sensitive to bacterial collagenase, indicating that the preparations did not contain any other constituents of the basement membrane (proteoglycan, laminin and entactin). Mouse type IV collagen-1 and -2 gave amino acid compositions characteristic of the type IV collagen reported earlier, although they had 20 to 30% higher glutamic acid content than the pepsin extracted collagens from other sources.These results suggest that the present collagenous protein and the antiserum against it might be useful tools for elucidating the roles of type IV collagen in vivo, since the mouse is utililzed in various models of diseases.

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A major glucoamylase [EC 3.2.1.3] from a Rhizopus sp., Gluc₁, was polymerized by crosslinking with glutaraldehyde. The polymerized Gluc₁ (named poly-Gluc₁) showed a drastic decrease (55%) in lysine content as well as a slight decrease (11%) in tyrosine content as compared with Gluc₁ and had an apparent molecular weight higher than 10⁶ daltons as estimated by gel filtration on Sepharose 6B. The circular dichroism spectrum, together with the ultraviolet and fluorescence spectra, indicated that poly-Gluc₁ was different from Gluc₁ not only in the states of aromatic amino acid side chains but also in the protein backbone conformation. The stabilities of poly-Gluc₁ to pH and heat were not enhanced appreciably as compared with those of Gluc₁, though the heat stability showed a slight enhancement at 40-45°C followed by a sharper decline at higher temperatures. For low-molecular-weight substrates, poly-Gluc₁ had similar kinetic parameters and activities to those of Gluc₁, whereas for high-molecular-weight substrates, poly-Gluc₁ showed 2-10 times higher K_m and 2-4.5 times lower V_max values and thus 2-4.5 times lower activities. Poly-Gluc₁ exhibited 25 times lower activity than Gluc₁ towards raw starch but was still tightly bound to it, suggesting that the lysine residues are not involved in the binding to raw starch.

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The adsorption of ammonium ion by three types of synthetic hydrated aluminum silicate (ZPC-10A, ZPC-50A and Molequlite 401) was studies to assess their possible utility as orally administered adsorbents for the treatment of uremia and ammoniemia. In vitro and preliminary in vivo studies suggest that ZPC-10A is promising as an adsorbent in terms of adsorption capacity, ion selectivity and resistance to acidity.

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The rabbit model of warfarin-induced hypoprothrombinemia was statistically investigated in terms of the relation between prothrombin time (PT) and prothrombin complex activity (PCA). Among various thromboplastin reagents examined, Simplastin-A was used because of its relatively distinct endpoint in the manual tilt-tube method and convenient coagulation time. The PCA 60%, selected as a measure for assessing the coagulation recovery induced by various oral vitamin K₁ preparations after experimental hypoprothrombinemia in the previous work (Nagata et al., J. Pharm. Pharmacol., 36, 527 (1984)), was confirmed to be a reasonable criterion to judge whether the coagulation recovery reaches normal based on a regression analysis of the compiled standard curves of PCA (n=194). The regression equation was given by log PT(s)=1.78-0.428×logPCA (%), r=0.996. The criterion of PCA 20% or less for maximal warfarin-induced hypoprothrombinemia was also justified (13.5±8.5%, n=102). The advantages of the rabbit model include repeated availability of the same animal (at intervals of more than 3 weeks), and the convenient PT difference between PCA 60% and 20% (6-8s).

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The effects of cinnamon bark and zanthoxylum fruit on various digestive enzymes were investigated. Both crude drugs were without effect on starch-dextrinizing activity of diastase and protein-peptic activity of biodiastase. Starch-saccharifying and starch-dextrinizing activities of pancreatin were inhibited by both crude drugs, while the protein-peptic activity of pancreatin was inhibited only by zanthoxylum fruit to below 30% of the activity in the absence of the crude drug. Both crude drugs inhibited starch-saccharifying activity of diastate, lipid-peptic activity of pancreatin and cellulose-saccharifying activity of biodiastase by 30 to 40%.The effects of cinnamon bark and zanthoxylum fruit on digestive enzymes in gastric and intestinal juice collected from rats were investigated. Starch-dextrinizing, starch-saccharifying and protein-peptic activities of intestinal juice were decreased by the crude drugs, zanthoxylum fruit being more inhibitory than cinnamon bark.To investigate the effects of the crude drugs on digestive enzymes in vivo, 600 mg (5 μCi) of either ¹²⁵I-bovine serum albumin or ¹²⁵I-egg white albumin was orally administered to rats 10 min after administration of 100 mg of cinnamon bark or zanthoxylum fruit. Radioactivity transferred to the blood was less in the animals pre-fed with zanthoxylum fruit than in the control animals, indicating that digestion of either bovine serum albumin or egg white albumin was delayed in the presence of the crude drug.

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