The crystal structure of 3'-O-benzoylthymidine has been determined by X-ray diffraction analysis. The crystals are monoclinic, space group P2₁ with the following cell dimensions : a=12.528 (6), b=6.544 (2), c=10.770 (5) Å, β=102.80 (5)°. The structure was solved by a combination of the Patterson and direct methods and refined to a crystallographic R factor of 0.053 by full-matrix least-squares refinement. The thymine and phenyl rings of neighboring molecules associate through stacking interactions. The glycosidic torsion angle (χCN=49.3 (4)°) is in the anti region and the deoxyribose ring conformation is C (2')-endo, while the conformation about the C (4')-C (5') bond is gauche-gauche.

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The structures of momordica saponins I and II, the seed saponins of Momordica cochinchinensis SPRENG. (Cucurbitaceae) have been elucidated on the basis of spectral and chemical evidence as the 3-O-β-D-galactopyranosyl (1→2)-[α-L-rhamnopyranosyl (1→3)]-β-D-glucuronopyranosido-28-O-β-D-xylopyranosyl (1→3)-β-D-glucopyranosyl (1→3)-[β-D-xylopyranosyl (1→4)]-α-L-rhamnopyranosyl (1→2)-β-D-fucopyranosides of gypsogenin and quillaic acid, respectively. I and II are contained in the seed kernels in a carboxylate form.

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Four new furanoditerpenes, 6-hydroxyarcangelisin (1a), 2-dehydroarcangelisinol (2), tinophyllol (3a) and 6-hydroxyfibleucin (4b), which were isolated from the Indonesian traditional medicinal plant, Arcangelisia flava MERR. (Menispermaceae), have been shown to have the structures illustrated in Chart 1. Fibraurin (5a), 6-hydroxyfibraurin (5d) and fibleucin (4a), which were isolated from the same plant extract, were also identified. Assignments of the ¹³C-nuclear magnetic resonance signals of the isolated furanoditerpenes and their derivatives were carried out.

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3, 3-Diethyl-(IIa, b) and 3-methyl-3-(3-pyridylmethyl)-1-nitroso-1-tolylureas (IIc, d) were prepared from the corresponding ureas (Ia-d). 3, 3-Dialkyl-1-(2-tolyl) nitrosoureas (IIa, c) decomposed to produce 3, 3-dialkyl-1-(2-tolyl) triazenes (IIIa, c) at room temperature. On the other hand, 3, 3-dialkyl-1-(4-tolyl) ureas (IIb, d) gave mainly the corresponding triazenes (IIIb, d) in protic solvents, although IIb, d gave 3, 3-dialkyl-1-(2-nitro-4-tolyl) ureas (IVb, d) and the denitrosated products (Ib, d) in chloroform or carbon tetrachloride.

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Treatment of (2-hydroxyethyl) urea derivatives (Ia-e) with sodium nitrite in the presence of acids or with nitrosyl chloride in chloroform gave 3-nitroso-2-oxazolidinones (IIa-e) in 10-77% yields. These 3-nitroso-2-oxazolidinones were denitrosated with hydrogen chloride in methanol to give the corresponding 2-oxazolidinones (IIIa-e) in 35-60% yields. An N, N-disubstituted urea, 1-(2-hydroxyethyl)-1-methylurea (If) also cyclized to give 3-methyl-2-oxazolidinone (IIf) under the same conditions. The mechanism of this type of cyclization is discussed.

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As a part of our search for new types of detergent useful for biological applications, a series of alkyl-β-D-thioglucopyranosides was synthesized in several steps from glucose. The overall yield was about 80%. Critical micelle concentrations of n-hexyl-, n-heptyl-, n-octyl-, and n-nonyl-β-D-thioglucopyranoside were determined. Because of their electroneutrality, high solubility in water and high critical micelle concentration, n-heptyl-and n-octyl-β-D-thioglucopyranoside seem to be potentially useful detergents for applications in biological systems.

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Three methods have been developed for the preparation of (S)-3-amino-2-tert-butoxycar-bonylaminopropionamide suitably protected for use in the total synthesis of bleomycin.

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An efficient synthesis of the pyrimidine nucleus of bleomycin was achieved. The reaction of diethoxyacetamidine and ethyl ethoxalylpropionate gave ethyl 2-diethoxymethyl-6-hydroxy-5-methylpyrimidine-4-carboxylate in 76% yield ; this product was then converted into ethyl 6-chloro-2-formyl-5-methylpyrimidine-4-carboxylate in 85% yield by treatment with POCl₃.

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New methodology was developed for the introduction of an acetate unit into the Schiff base 2, based on the reaction of the Schiff base 2 with malonic acid monoester or vinyloxyborane. Furthermore, the synthesis of Boc-pyrimidoblamic acid, a key fragment for the total synthesis of bleomycin, was achieved by utilizing these two methods.

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Six phenolic compounds were isolated from Coptidis Rhizoma and were identified as 3-(3', 4'-dihydroxyphenyl)-(2R)-lactic acid, 3-(3', 4'-dihydroxyphenyl)-(2R)-lactic acid 4'-O-β-D-glucopyranoside, 3', 4'-dihydroxyphenethyl alcohol 1-O-β-D-glucopyranoside, gentisic acid 5-O-β-D-glucopyranoside, 4-O-feruloyl-D-quinic acid and 5-O-feruloyl-D-quinic acid.

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An efficient total synthesis of (±)-decaline and (±)-vertaline, lactonic biphenyl ether Lythraceae alkaloids, was achieved. The [3+2] cycloaddition of the nitrone (24) with the olefin (10), prepared via the Ullmann reaction catalyzed by a phase-transfer reagent, produced the adduct (11) which, upon treatment with methanesulfonyl chloride followed by reductive cleavage of the N-O bond, gave the isomeric quinolizidinols (13 and 14) in a one-pot operation. Through the use of inter-and intramolecular Mitsunobu reaction as an inversion procedure at C-2, 13 was converted into (±)-decaline (1). On the other hand, the cis-quinolizidinol (14) was transformed in two steps to (±)-vertaline (2).

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The glycosphingolipids isolated from spermatozoa of a fresh-water bivalve, Hyriopsis schlegelii, have a unique structure containing one or two mannosyl residues. We synthesized the trisaccharide derivatives which constitute the partial structure of lipid I and/or II. Condensation of 3, 4, 6-tri-O-acetyl-2-deoxy-2-phthalimido-β-D-glucopyranosyl bromide with methyl 3-O-benzyl-4, 6-O-benzylidene-α-D-mannopyranoside in the presence of mercuric cyanide gave methyl 3-O-benzyl-4, 6-O-benzylidene-2-O-(3, 4, 6-tri-O-acetyl-2-deoxy-2-phthalimido-β-D-glucopyranosyl)-α-D-mannopyranoside in 80% yield. Condensation of the disaccharide bromide with the appropriate C-3 hydroxyl free mannose derivatives afforded the corresponding GlcNAcβ1→2Manα1→3Man derivatives (11 and 12).

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3-Acylmethyleneoxindoles (Ia-d) reacted with active methylene compounds (IIa-d) in EtOH, in the presence of NaOC₂H₅ as a catalyst at room temperature, to afford the corresponding normal Michael adducts (IIIa-f). The reactions of Ia with IIa, Ic with IIa and Id with IIa in EtOH under reflux, in the presence of Et₂NH as a catalyst, produced the corresponding 2', 4'-substituted 3-(5'-amino-2'H-furan-3'-ylidene) oxindoles (IVa-c), while the reactions of Ib with IIa, Ib with IIb and Ic with IIb afforded the 2', 4'-substituted 3-(5'-amino-3'-furyl) oxindole compounds (Va-c), respectively. The Michael adducts (IIIa-c), on being refluxed in EtOH with base catalyst, gave IVa, Vb and IVb, respectively, in high yields, whereas IIId-f did not change at all. X-Ray crystallographic analyses of IVb and Vb were performed.

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Treatment of 3-aroylpropionic acids (1) with thallium (III) nitrate causes smooth 1, 2-aryl migration to give dimethyl 2-arylsuccinates (2) in good yields. Similar transformation of 5-arylfuran-2 (3H)-ones (3) with thallium (III) nitrate to 1-methyl 2-arylsuccinates (4) is also described.

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Neutral constituents of Hypericum mysorense HEYNE, collected in Sri Lanka, were examined. Hyperenone-A, mysorenone-A, and compound-C (methyl phenacyl 1, 1-dimethylprop-2-enyl-malonate) were isolated and their structures were determined on the basis of chemical and spectroscopic evidence. Four known xanthones were also isolated and identified.

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The cyanation of 3-halo-, 3-methoxy-, and 3-dimethylaminopyridine 1-oxide with trimethylsilanecarbonitrile gave predominantly the corresponding 3-substituted 2-pyridinecarbonitriles. The deoxygenation of nitropyridine 1-oxides to nitropyridines with the same reagent is also described.

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Acetyl glyceryl ether phosphorylcholines (platelet-activating factors ; PAFs), their enantiomers, and their analogues were efficiently synthesized in a stereochemically unambiguous manner starting from D-and L-tartaric acids as chiral synthons. The enantiomer of C₁₆-PAF (S-comfiguration) showed far less activity than the natural PAF (R-configuration), and the N-methylpiperidine and N-methylpyrrolidine analogues were found to possess much higher activity than natural C₁₆-PAF.

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With a view to establishing the structure of the Alangium alkaloid desmethylpsychotrine, (+)-9-demethylpsychotrine [(+)-1] has been synthesized from ethyl cincholoiponate [(+)-6] and 3-benzyloxy-4-methoxyphenacyl bromide by the "cincholoipon-incorporating method" through the intermediates (+)-7, 8, 10-(+)-14, and (+)-17-(+)-22. The identity of synthetic (+)-1 with natural desmethylpsychotrine unequivocally established the structure of this alkaloid.

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The coloration mechanism in the Ehrlich reaction between furostanol glycoside and p-dimethylaminobenzaldehyde has been studied. From the reddish reaction mixture of protoaspidistrin, one of the furostanol saponins, with Ehrlich reagent, colorless condensation products were isolated and characterized as methyl 23-(p-dimethylaminobenzylidenyl)-proto-aspidistrin (5), 3, 26-dihydroxy-23-(p-dimethylaminobenzylidenyl)-furost-5, 20 (22)-diene 3-O-β-D-galactopyranosido-26-O-β-D-glucopyranoside (9), 23-(p-dimethylaminobenzylidenyl)-diosgenin (6), 3β-hydroxy-26, 7'-epoxy-23-(p-dimethylaminobenzyl)-furost-5, 20 (22)-diene (7) and a stereoisomer of 7 (8). Among these products, compounds 5, 9 and 6 showed red coloration under acidic conditions, while compounds 7 and 8, which should not be able to form iminium cations under acidic conditions, did not show the red coloration. It was concluded that the Ehrlich reaction is initiated by condensation between p-dimethylaminobenzaldehyde and furostanol saponin to form 23-benzylidenyl derivatives, which are protonated to form iminium cations under acidic conditions.

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Two new bisdesmosides of soyasapogenol A (1), named soyasaponin A₁ and soyasaponin A₂ (7), were isolated from soybean, the seeds of Glycine max MERRILL, together with the known soyasaponins I (4), II (5), and III (6). By employing a photochemical degradation method, which is a selective cleavage method for the glucuronide linkage in oligoglycosides, and on the bases of spectral analyses and chemical reactions, the structure of soyasaponin A₂ was elucidated as 3-O-[β-D-galactopyranosyl (1→2)-β-D-glucuronopyranosyl]-22-O-[β-D-glucopyranosyl (1→3)-α-L-arabinopyranosyl] soyasapogenol A (7).

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A highly efficient synthesis of the antitumor steganin lignan steganacin (1) was accomplished. Bromination of stegane (7) with N-bromosuccinimide followed by treatment with aqueous tetrahydrofuran afforded steganol (3) in 85% yield. Acetylation of 3 gave 1 in 72% yield. Stegane (7) was also oxidized with 2, 3-dichloro-5, 6-dicyano-1, 4-benzoquinone in AcOH to give 1 directly in 10% yield. Stereochemical requirements for the benzylic oxidation of dibenzocyclooctadiene lignan lactones are discussed.

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Thiazolo [4, 5-g] quinazoline 3-oxides and thiazolo [5, 4-f] quinazoline 3-oxides, the N-oxides of new heterocyclic systems, were synthesized and their chemical properties were investigated. Namely, the reaction of 7-chloro-1, 3-dimethyl-6-nitroquinazoline-2, 4 (1H, 3H)-dione (1) with methyl thioglycolate in the presence of triethylamine gave 7-methoxycarbonylmethylthio-1, 3-dimethyl-6-nitroquinazoline-2, 4 (1H, 3H)-dione (2) and subsequent treatment of 2 with pyrrolidine resulted in base-catalyzed dehydrative cyclization to afford 2-methoxycarbonyl-6, 8-dimethylthiazolo [4, 5-g] quinazoline-5, 7 (6H, 8H)-dione 3-oxide (3) and 6, 8-dimethyl-2-pyrrolidinocarbonylthiazolo [4, 5-g] quinazoline-5, 7-(6H, 8H)-dione 3-oxide (5). On the other hand, the reaction of 5-chloro-1, 3-dimethyl-6-nitroquinazoline-2, 4 (1H, 3H)-dione (10) with methyl thioglycolate in the presence of triethylamine directly yielded 2-methoxycarbonyl-6, 8-dimethylthiazolo [5, 4-f] quinazoline-7, 9 (6H, 8H)-dione 3-oxide (11). These N-oxides were confirmed to be useful starting materials for the preparation of a variety of thiazolo [4, 5-g]- and [5, 4-f] quinazoline derivatives.

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Four kinds of naphthyridinones, i.e. 1, 6-naphthyridin-5-one, 1, 7-naphthyridin-8-one, 2, 6-naphthyridin-2-one, and 2, 7-naphthyridin-1-one derivatives, were commonly synthesized by the intramolecular cyclization of pyridinecarboxamides having an ethynyl group or β, β-dimethoxyethyl group adjacent to the carbamoyl group. The syntheses of the starting pyridine derivatives were easily accomplished by cross-coupling of the corresponding halopyridines with acetylenes.

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The reaction of methyl trans-3-(4-methoxyphenyl) glycidate (1) with 2-nitrophenol was investigated under various conditions. Generally, the reaction proceeded predominantly by cis-opening of the oxirane ring of 1 to give the threo-nitro ester (7). Selective trans-opening of 1 was observed only in the reaction with sodium 2-nitrophenoxide to give the erythro-nitro ester (8). Some 1, 5-benzoxazepine derivatives (16-19), 1-oxa analogues of diltiazem, were synthesized from 7 and 8 for pharmacological evaluation. Compound 18a showed the highest vasodilating activity in this series, but it was less active and more toxic than racemic diltiazem.

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Modulation of hyaluronidase activities by various compounds which are closely related with the degranulation of the mast cells was studied. It was found that compound 48/80, a non-specific histamine releaser from mast cells, activated hyaluronidase strongly. Hyaluronidase activated by CaCl₂ or compound 48/80 was inhibited by anti-allergic agents such as disodium cromoglycate (DSCG) or tranilast. On the other hand, tranilast greatly enhanced the activity of the hyaluronidase activated by NaCl. The inhibitory effects of these anti-allergic agents on the activation of the inactive hyaluronidase were shown to be stronger than those on activated hyaluronidase. Since the hyaluronidase activity was modulated by compounds closely associated with allergic phenomena, it is suggested that the hyaluronidase might be present as one of the target enzymes of the influent calcium ions in the mast cells and might directly control the degranulation.

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trans-4-Guanidinomethylcyclohexanecarboxylic acid (trans-GMCHA) aryl esters were synthesized and tested for inhibitory effects on serine proteases, trypsin, chymotrypsin, plasmin, plasma kallikrein, pancreatic kallikrein, urokinase and thrombin. In general, these compounds showed strong inhibitory effects on chymotrypsin, pancreatic kallikrein and urokinase, but the effects varied greatly depending on the substituent in the benzene nucleus. Some of the trans-GMCHA aryl esters strongly inhibited compound 48/80-induced histamine release from mast cells / the p-tert-butylphenyl ester was especially active.

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A newly synthesized 18-membered hexaamine carrying an acetate moiety on each nitrogen, L², has been demonstrated to be a more efficient dissolving agent that ethylenediaminetetraacetic acid for human urinary calculi whose major components are calcium phosphate and magnesium phosphate. L² is a good chelating agent for Ca²⁺ and Mg²⁺, and this chelating action is presumably responsible for the dissolution of inorganic calculi.

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Various N-aryl-N'-phenylthioureas, N, N'-diarylthioureas and N-(1, 2, 4-triazol-3-yl)-N'-arylthioureas were prepared and examined for uncoupling activities. The results indicate that substitution at the 4-position of the phenyl groups of diaryl thioureas is very important for uncoupling activities. Diphenyl thioureas substituted with two or more halogen atoms exhibited strong activities. The highest activity was exhibited by a compound containing nitro groups on both phenyl groups. These results indicate that the hydrophobicity and acidic nature of the compound are of primary importance for uncoupling activities. A remarkable decrease in activity was observed with the thioureas which were substituted with pyridine and 1, 2, 4-triazole rings. The reaction of phenyl isothiocyanate with 3-amino-1, 2, 4-triazole was also studied.

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A novel fluorometric assay method was established for latamoxef (LMOX), a new type of antibiotic. LMOX was converted into 1, 2, 4-dihydroxy-3-[(1-methyltetrazol-5-ylthio) methyl] but-2-enoic acid γ-lactone, in an acid solution. The lactone 1 reacted with 2, 6-diamino-3-nitrosopyridine to give the fluorophore, 3-(5-amino-3H-imidazo [4, 5-b] pyridin-2-yl)-2, 4-dihydroxybut-2-enoic acid γ-lactone. The fluorescence was measured at 460 nm with excitation at 392 nm. In plasma and urine, 1-15 μg/ml and 20-300 μg/ml of LMOX were determined, respectively, with good precision through a simple technique. The sample volume was 100 μl. The reaction mechanism of the fluorescence reaction is discussed.

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N-Bromoacetylsulfanilyl chloride and p-bromoacetamidobenzoyl chloride were synthesized as heterobifunctional reagents for the cross-linking of sugar with protein. These reagents react with the primary hydroxyl group of a sugar at the acid chloride group and with amino and imidazole groups of protein at the bromoacetyl group. Methyl α-D-glucoside, selected as a model sugar, reacts with these reagents to form methyl 6-O-(N-bromoacetylsulfanilyl)-α-D-glucoside and methyl 6-O-(p-bromoacetamidobenzoyl)-α-D-glucoside, respectively. These sugar derivatives combine with bovine serum albumin at weakly alkaline pHs. More than 10 of the sugar derivatives can be incorporated into one molecule of the albumin.

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A bovine serum albumin conjugate of 2-hydroxyestradiol 17-sulfate was used for antibody preparation in rabbits. The hapten was linked to the carrier protein through the C-6 position on the steroid nucleus. The antibody obtained possessed extremely high specificity to 2-hydroxyestradiol 17-sulfate, exhibiting essentially no cross-reactions with other related steroids and their conjugates.

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In vitro sulfation of catechol estrogens with guinea pig and rat liver homogenates has been investigated by means of high-performance liquid chromatography with electrochemical detection. When incubated in a neutral medium (pH 7.4) with the liver 105000 g supernatant fortified with 3'-phosphoadenosine-5'-phosphosulfate, 2-hydroxyestrone and 4-hydroxyestrone were transformed principally into the 2- and 4-sulfates, respectively. The 3-sulfate was formed, and decreasing amounts of the 2- and 4-sulfates were obtained, as the pH of the incubation medium was decreased. The pH effect on directive glucuronidation was also examined with catechol estrogens. The product ratio of the isomeric ring A glucuronides formed was not affected by the pH of the incubation medium.

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The inhibitory effects of caffeoylquinic acids isolated from the leaves of Artemisia species on the histamine release from rat mast cells induced by compound 48/80, and on that induced by concanavalin A plus phosphatidylserine were determined. At the concentration of 2.5×10^-5M, caffeic acid, chlorogenic acid and methyl chlorogenate exhibited over 50% inhibition of the histamine secretion induced by compound 48/80 from mast cells. The inhibitory effects of caffeic acid and monocaffeoylquinic acids (chlorogenic acid and methyl chlorogenate) were higher than those of dicaffeoylquinic acids on the compound 48/80-induced histamine release from mast cells. On the other hand, caffeic acid, chlorogenic acid and 3, 5-di-O-caffeoylquinic acid exhibited over 50% inhibition of the histamine secretion induced by concanavalin A plus phosphatidylserine from mast cells at the concentration of 10^-5M.

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The role of calcium in the thermal stability of semi-alkaline proteinase (SAP) from Aspergillus melleus was investigated. As removal of calcium from active SAP induced an autolytic degradation, phenylmethylsulfonyl fluoride-modified SAP (PMS-SAP), having no proteolytic activity, was used. The calcium binding isotherm obtained by equilibrium gel chromatography indicated that PMS-SAP bound a maximal amount of 2 mol of calcium per mol of enzyme. The results of high-performance liquid chromatography and differential scanning calorimetry of the EDTA-treated PMS-SAP suggested that removal of calcium lowered the transition temperature of the thermal denaturation, accompanied with a decrease in the enthalpy change (ΔH) and in the entropy change (ΔS) for the denaturation. No significant change was observed in the circular dichroism spectrum or immunological properties when one of the two calciums was removed from PMS-SAP. The other one was not removed by dialysis against various concentrations of EDTA or EGTA at pH 8.0, but was removed when PMS-SAP was irreversibly denatured under acidic conditions (pH 2.0). It seems likely that the calcium atom which is removed by dialysis is present on the surface of the enzyme molecule and stabilizes the enzyme against thermal denaturation, whereas the remaining calcium atom seems to be firmly bound to the enzyme or buried in the molecular interior.

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Deoxypodophyllotoxin (I), which was isolated from Anthriscus sylvestris HOFFM., has strong toxic activity towards killifish (Oryzias latipes) (TLm₄₈ : 0.058ppm) and shrimp (Altemia salina) (TLm₄₈ : 0.15 ppm). Furthermore, I exhibited the phytogrowth-inhibitory activity against two kinds of plant roots. On the other hand, deoxypicropodophyllin (II), a stereoisomer of I, showed none of these activities. From these results it can be assumed that the difference of activity between I and II is due to a difference in their conformations. Through analysis of the proton nuclear magnetic resonance spectra it was clarified that 1) the conformation at the 5a position of I is quasi-equatorial, whereas that of II is quasi-axial, and 2) the B-ring of I takes a half-chair form, whereas that of II takes a half-boat form.

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Neogalactobiose (α-D-galactopyranosyl β-D-galactopyranoside), β-D-galactopyranosyl β-D-glucopyranoside, β-D-galactopyranosyl α-D-glucopyranoside, α-D-galactopyranosyl β-D-glucopyranoside (GII), and α-D-galactopyranosyl β-D-fructofuranosyl-(2→6)-β-D-fructofuranoside (Gf) were synthesized as sugar sources which might selectively and efficiently enhance the growth of bifidobacteria in the human intestines. Gf was synthesized by using levansucrase and the others by means of the Koenigs-Knorr reaction. The structures of these sugars were confirmed by enzymic hydrolysis. All of these sugars were utilized by almost all strains of Bifidobacterium tested. Among them, GII, Gf and stachyose were not utilized by Lactobacillus acidophilus or Streptococcus faecalis, and were utilized by only a few strains of Enterobacteriaceae (comparable to lactosucrose). Furthermore, as regards both the growth activity of bifidobacterial cells and the generation time of the cells, the three sugars were virtually as effective as lactose or lactosucrose.

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An intraperitoneal (i.p.) injection of rhatannin (12.5mg/kg body weight, condensed tannin purified from Rhei Rhizoma) decreased the concentration of plasma amino acids in rats. The early effect of rhatannin on the levels of amino acids was compared with those of selected hormones. Although glucagon (0.5mg/kg), adrenaline (0.5mg/kg), and corticosterone (0.5mg/kg) exerted similar decreasing effects on amino acids, the effects of rhatannin and glucagon were different from those of the others in that only these two substances caused a decrease in lysine concentration. Rhatannin also increased the levels of plasma glucose and urea 2h after i.p. administration in rats starved for 24h. The effects of rhatannin observed in the present study cannot be ascribable to its effect on the levels of glucagon and insulin, since rhatannin did not affect the physiological levels of these hormones. Glucose release from liver cells in the presence of glucagon was synergistically enhanced by rhatannin, although rhatannin itself had no effect on basal glucose release from liver cells. When this synergistic effect of rhatannin was examined at 10nM glucagon, glucose release increased with an increase in the rhatannin concentration. The maximal level of enhancement was achieved at rhatannin concentrations ranging from 5 to 60μg/ml. On the other hand, glucose release induced by adrenaline or dibutyryl adenosine 3', 5'-cyclic monophosphate (dibutyryl c-AMP) was not affected by rhatannin. Thus, it was suggested that the effects of rhatannin on plasma amino acids, glucose, and urea observed in vivo might be mediated by rhatannin's primary effect on the glucagon regulatory pathway.

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The effect of ginsenoside-Rb₂ purified from ginseng on lipid metabolism was examined in rats fed on a high cholesterol diet. A single intraperitoneal administration of ginsenoside-Rb₂ produced a significant decrease of total cholesterol, free cholesterol, low density lipoprotein (LDL)-cholesterol, triglyceride, 3-hydroxybutyrate, and acetoacetate levels in the serum. However, a significant increase of high density lipoprotein (HDL)-cholesterol level in the serum was observed after the treatment. Repeated administration of ginsenoside-Rb₂ to rats with hyperlipemia induced by a high-cholesterol diet resulted in a striking decrease in the levels of total cholesterol, free cholesterol, LDL-cholesterol, and triglyceride, whereas the level of HDL-cholesterol was again increased. The changes were larger than those produced by a single intraperitoneal administration. Furthermore, the lipolytic activity of lipoprotein lipase was stimulated with a concomitant decrease in the levels of triglyceride and very low density lipoprotein (VLDL)-triglyceride in the serum. Accumulation of lipid in the adipose tissue was observed. In addition, a slight decrease in hepatic total cholesterol was observed after the treatment, but there was no statistically significant difference between the control and ginsenoside-Rb₂-treated groups. The mechanism of hypolipemic action of ginsenoside-Rb₂ is discussed on the basis of these results.

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Two disaccharide nucleosides, 5-fluoro-2', 3'-isopropylidene-5'-O-(4-N-acetamido-2, 4-dideoxy-3, 6, 7, 8-tetra-O-acetyl-1-methoxycarbonyl-D-glycero-α-D-galacto-octapyranosyl) uridine (KI-8110) and 2', 3'-di-O-acetyl-5'-O-(4-N-acetamido-2, 4-dideoxy-3, 6, 7, 8-tetra-O-acetyl-1-methoxycarbonyl-D-glycero-α-D-galacto-octapyranosyl) inosine (KI-8115) decreased in corporation of sialic acid into glycoconjugates on the murine lymphocyte surface. Since sialidase (EC 3.2.1.18) activity, CMP-NeuAc hydrolase (EC 3.1.4.40) activity and the incorporation of galactose or N-acetylgalactosamine into cell-surface glycoconjugates were all unaffected by these disaccharide nucleosides, the observed decrease in incorporation of sialic acid into glycoconjugates is considered to reflect the inhibition of sialyltransferase (EC 2.4.99.1) on the lymphocyte surface. KI-8110 and KI-8115 specifically inhibited the transfer of sialic acid to exogenous desialylated glycoproteins or exogenous desialylated glycolipids. Namely, KI-8100 and KI-8115 inhibited the transfer of sialic acid to desialylated fetuin, porcine submaxillary mucin (PSM) and bovine submaxillary mucin (BSM), all of which have Ser (Thr)-linked oligosaccharide chains, but did not inhibit transfer to desialylated α₁-acid glycoprotein, which has only Asn-linked oligosaccharide chains. KI-8110 and KI-8115 inhibited the transfer of sialic acid to desialylated gangliosides GA₁ and GA₂, but not GA₃. By using p-nitrophenyl-β-D-galactoside as an acceptor and cytidine 5'-monophosphate-[¹⁴C] N-acetylneuraminic acid (CMP-[¹⁴C] NeuAc) as a donor, two types of sialyl derivatives, α-sialosyl-(2→3)-p-nitrophenyl-β-D-galactoside and α-sialosyl-(2→6)-p-nitrophenyl-β-D-galactoside, were produced in murine lymphocytes. The production of α-sialosyl-(2→3)-p-nitrophenyl-β-D-galactoside was specifically inhibited by KI-8110 and KI-8115. KI-8110 and KI-8115 competitively inhibited sialic acid transfer by lymphocyte sialyltransferase to desialylated fetuin as an exogenous acceptor. The apparent K₁ values were 2.3mM for KI-8110 and 2.5mM for KI-8115. When cytidine 5'-diphosphate (CDP), a known inhibitor of sialyltransferase, was incubated with lymphocyted for 24 h at 37°C, the inhibitory activity of CDP was dramatically decreased. However, such incubation did not affect the inhibitory activity of KI-8110 or KI-8115.

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[Asu^{1, 7}]-eel calcitonin ([Asu^{1, 7}]-ECT) was not absorbed well from rat rectum. Although an unstirred layer may exist as a diffusion barrier for [Asu^{1, 7}]-ECT absorption, transport through the epithelial cell membrane is the limiting step for [Asu^{1, 7}]-ECT absorption. Coadministration of 0.33M phenylalanine enamine of ethylacetoacetate (PheEtAA), 0.17M diethylethoxymethylenemalonate (DEEMM), 0.6M sodium salicylate (SA), or 0.05M sodium p-chloromercurylphenyl sulfate (p-CMP) increased the rectal [Asu^{1, 7}]-ECT absorption significantly. In particular, PheEtAA and DEEMM resulted in a more than 180 times greater AUC of [Asu^{1, 7}]-ECT compared to that when [Asu^{1, 7}]-ECT alone was administered rectally, and these two adjuvants were more effective than SA and p-CMP on the rectal [Asu^{1, 7}]-ECT absorption, though all four adjuvants coadministered at the above concentration with sodium cefmetazole caused similar increases of rectal cefmetazole absorption.

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The quality of commercially available semi-alkaline proteinase (SAP) preparations was studied by using high-performance liquid chromatography (HPLC) on a TSK G-3000 SW column, with 0.2M phosphate buffer (pH7.0) containing 0.1% sodium dodecyl sulfate (SDS) as a mobile phase. We could quantitatively separate SAP from enteric coating, excipients and degradation products of SAP in pharmaceuticals of various dosage forms, and follow the changes in their activities during storage. When the content of SAP in pharmaceuticals was determined by this HPLC method, commercially available SAP preparations were found to contain 60-78% of the labeled amount of SAP. HPLC chromatograms obtained in the heat stability test demonstrated that SAP both in the liquid and the solid state is degraded into small fragments in the course of inactivation. Inactivation of powdery SAP by ultraviolet irradiation and by compression force in tabletting could also be followed by using HPLC. This simple and precise HPLC method was proved to be useful for assessing the stability of SAP preparations and for investigating the mechanism of inactivation of this enzyme.

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It was observed that alkyl glycosides formed lamellar vesicles like phosphatidylcholine vesicles (liposomes), and the application of these vesicles as drug carriers was attempted. Various alkyl glycosides were synthesized and vesicles were prepared with these glycosides. The encapsulation capacity of the vesicles was examined in relation to alkyl chain length, sugar moiety, and lipid composition. The glucosides of myristyl, cetyl, and stearyl alcohols formed vesicles, but those of lauryl, decyl, and octyl alcohols did not. The vesicles of glucoside, galactoside, and mannoside showed fairly good encapsulation capacity but those of lactoside showed low capacity. An appropriate ratio of glycoside, cholesterol, and dicetylphosphate is an important factor for the formation of these vesicles, especially with regard to dicetylphosphate. The alkyl glycoside vesicles show longer lives on stage in an ampule at 20°C than phosphatidylcholine vesicles. The stability in plasma was also examined. The glycoside vesicles showed rapid release of about 40% of the aqueous contents, but after that, they showed outstanding stability for 48h in plasma at 37°C. On the other hand, phosphatidylcholine vesicles showed rapid release of only about 30%, but they disintegrated gradually and showed low encapsulation capacity (about 20%) after 48h. The present results suggest that the application of alkyl glycoside vesicles as drug carriers may be feasible.

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After oral administration of deuterium-labeled pseudoracemic D-32 to human subjects, the enantiomeric metabolites in plasma and urine were analyzed by gas chromatography-mass spectrometry. D-32 was biotransformed to 3 major metabolites, 4-hydroxy D-32, 3-hydroxymethyl D-32 and 3-carboxy D-32. Twenty-five percent of the racemic dose was excreted into the urine as 4-hydroxy D-32, and 80% of 4-hydroxy D-32 in the urine was derived from (-)-D-32. Sixty percent of 3-carboxy D-32 in the urine was derived from (+)-D-32. About 1% of the racemic dose was excreted into the urine as unchanged material, but of this, in which (+)-D-32 amounted to 3-5 times more than (-)-D-32. The area under the plasma concentration-time curve of (-)-4-hydroxy D-32 was 2.6 times larger than that of (+)-4-hydroxy D-32. The half-lives of (-)-4-hydroxy D-32, (+)-4-hydroxy D-32 and both enantiomers of D-32 were 3.8, 2.4 and 3h, respectively. Thus, a marked difference in the metabolism between (-)-D-32 and (+)-D-32 was found. As 4-hydroxy D-32 and 3-hydroxymethyl D-32 are the active metabolites, the pharmacological effectiveness of D-32 after oral administration is represented by the total amount of (-)-4-hydroxy D-32 and (-)-3-hydroxymethyl D-32.

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Values for the acid dissociation constant K_a of various acidic and basic compounds were determined from the pH-dependent capacity factor k' by reversed-phase high-performance liquid chromatography (HPLC) with octadecyl silane as the stationary phase. Both the neutral and ionic forms of acids and bases were retained on the stationary phase, and k' of the ionic form markedly influenced the calculation of K_a value. Values of K_a determined by HPLC agreed well with those determined by the conventional potentiometric method, indication the availability of this method for the determination of K_a values. The "hydrophobicity" of the ionized forms of these compounds is discussed in terms of the partition coefficient of the neutral form between octanol and water.

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The interaction of salicylic acid with human serum albumin (HSA) was studied at 4°C by a frontal affinity chromatographic technique employing HSA monomer immobilized on agarose beads in two buffer system, i.e. Tris-HCl and phosphate buffers. A large difference in the apparent binding constants in these buffer systems was almost entirely attributed to the presence of chloride ions in Tris-HCl buffers. The inhibitory effect of chloride ions was directly demonstrated to be due to the binding of chloride ions to HSA, and other components of the buffers had little effect. The data can be interpreted on the basis of competitive binding at sites other than the primary chloride ion binding sites.

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The extraction ratio (E_c) and the mean cycle times (t^^-_c) for single systemic and pulmonary circulation were evaluated for 115 drugs in man. Heparin and fluorohydrocortisone, which have the smallest t^^-_c values (about 1min) show the small E_c values (close to zero). This result suggests that these drugs circulate through the body restricted within the blood vessels. The theoretical considerations indicate that the clearances defined by A_i (∞)/AUC differ from E_iQ_i, where A_i(∞) is the amount eliminated by organ i, AUC is the area under the plasma concentration curve, E_i is the extraction ratio and Q_i is plasma flow rate through organ i. The hepatic extraction ratios (E_h) of alprenolol, metoprolol and propranolol calculated from intravenous data alone are large (above 80%). It is also shown that the steady-state volume of distribution (V_ss) is rather independent of hepatic and renal extraction ratios, while the mean residence time (MRT) is considerably affected by change of these ratios.

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The effect of the crystallinity of a topically applied drug on its percutaneous absorption was investigated with hydrocortisone acetate as a model drug. To decrease the degree of crystallinity, the drug was ground with crystalline cellulose. The X-ray diffraction method for determining the degree of crystallinity was shown to be valid in the range of amorphous cellulose ratio of 0 to ca. 50% by using simple mixtures of glutathione and amorphous cellulose. Thus, the dissolution rate of hydrocortisone acetate was confirmed to increase quantitatively with decreasing crystallinity.

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Changes in the degree of crystallinity and in the dehydration and decomposition points of cephalexin (CEX) crystalline powder caused by tabletting were studied by means of X-ray diffraction analysis, infrared (IR) spectroscopy and differential thermal analysis (DTA). The degree of crystallinity of the compressed phase IV CEX was determined by the X-ray diffraction and IR-spectral methods, and the results agreed reasonably well. The maximum compression stress (MP) and the compression loss energy (LE) of phase IV CEX powder during tabletting compression were measured during compression in a single-punch tabletting machine. The degree of crystallinity of the compressed phase IV CEX decreased with increasing values of MP and LE, and was about 40% at LE=1.75 kcal/mol. The dehydration and decomposition points of the compressed phase IV CEX fell with decreasing degree of crystallinity. The plot of log (LE) against the degree of crystallinity showed a good straight line. The value of LE estimated by extrapolating the plot to zero crystallinity was 14.0 kcal/mol.

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The effects of Neurotropin (NSP) on lysosomal and microsomal enzyme activities, antioxidant levels and fatty acid composition of microsomal phospholipids in rat liver were studied before and after CCl₄ intoxication. The effect on in vitro lipid peroxidation was also determined. NSP posttreatment (60 mg/kg/d for 3 and 7 d after CCl₄) did not produce a significant recovery of the enzyme activities, while NSP pretreatment (60 mg/kg/d for 7 d before CCl₄) partly prevented the decrease in lysosomal enzyme activities after CCl₄ intoxication and increased the level of water-soluble antioxidants as compared with that of CCl₄-treated rats. NSP significantly decreased ascorbateinduced lipid peroxidation in vitro, by 20% at the concentration of 1 mg/ml, without affecting the reduced nicotinamide adenine dinucleotide phosphate (NADPH)-induced lipid peroxidation. Further, NSP significantly enhanced, by 20-23%, the protecting effect of inhibitors (CoCl₂ and aniline) of lipid peroxidation. Thus, NSP pretreatment appears to have a partial protecting effect against CCl₄ intoxication and accompanying lipid peroxidation.

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Derivatives of 3- and 4-acyloxy-1-(1, 3-dioxolan-4-ylmethyl) piperidine were synthesized and tested for atropine-like activities on the ileum from guinea pigs. The structure-activity relationship was assessed. Features favoring potent atropine-like action were considered to be as follows : (1) both the acyloxy group and the dioxolane ring should be diequatorial on the piperidine ring, (2) the acyloxy group should be moderately bulky, and (3) a substituent on the dioxolane ring is unnecessary. The highest activity (pA₂) determined was 8.64 which is about 50 times that of scopolamine N-butyl bromide.

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