The reactions of Cu^II(en)₂ (en : ethylenediamine) with hydrogen peroxide (H₂O₂) during the successive addition of a polyamine-N-polycarboxylate such as ida (iminodiacetic acid) and edta (ethylenediaminetetraacetic acid) were investigated by the thiobarbituric acid (TBA) method and by the electron spin resonance (ESR) titration method. A relatively good relation between TBA method and ESR titration method was observed.The ligand, en, in Cu^II(en)₂ was easily replaced by ida and edta. In the case of edta, which is a tetradentate ligand, Cu^II(edta) was formed when the concentration ratio of edta to Cu^II(en)₂ was 1. On the other hand, in the case of ida which is a bidentate ligand, the reactions between Cu^II(en)₂ and ida proceeded stepwise. That is, one is the formation of a mixed ligand complex of Cu(II), Cu^II(en)(ida), when the concentration ratio of ida to Cu^II(en)₂ was 1. The other is the formation of Cu^II(ida)₂ when the concentration ratio of ida to Cu^II(en)₂ was 2.A mixed ligand complex, Cu^II(en)(ida), exhibited activity towards H₂O₂, whereas Cu^II(ida)₂ and Cu^II(edta) did not show any activity towards H₂O₂. The different reactivities of these Cu(II) complexes toward H₂O₂ were discussed.

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2-Quinolyl thiocyanate (2) was found to react with C-nucleophiles, i.e., phenylacetonitrile, p-chlorophenylacetonitrile, p-cyanophenylacetonitrile, p-methoxyphenylacetonitrile, ethyl cyanoacetate, and malononitrile, in two ways, depending on the nature of the reagent. The more reactive phenylacetonitrile carbanions attacked at the less reactive sulfur atom, which is less subject to steric effect compared with the 2-position carbon of 2, to give the corresponding sulfides (α-(2-quinolylthio)phenyl- (8), α-(2-quinolylthio)-4-chlorophenyl- (9), α-(2-quinolylthio)-4-cyanophenyl- (10), and α-(2-quinolylthio)-4-methoxyphenylacetonitrile (11)). The less reactive ethyl cyanoacetate and malononitrile carbanions attacked at the more reactive 2-position carbon of 2 to afford the corresponding ipso-substitution products (α-cyano-2-quinolineacetate (4) and 2-quinolinemalononitrile (7)). However, in the reaction of diethyl malonate carbanion, diethyl 2-quinolinemalonate (12) was not obtained, presumably for steric reasons.

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It was found that (2+2) cycloaddition reaction of diketene with Schiff bases was effectively promoted by imidazole as a catalyst to afford 3-acetyl-2-azetidinone derivatives 4. As an application of this new method, a practical asymmetric synthesis of 4 and its conversion into (3S, 4S)-4-carboxy-1-(di-p-anisylmethyl)-3-[(R)-1-hydroxyethyl]-2-azetidinone, which is a key intermediate for the synthesis of carbapenem and penem antibiotics, were accomplished.

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We synthesized useful intermediates 5 and 6 for 1β- and 1α-methylcarbapenems from 4-carboxy-3-[(R)-1-hydroxyethyl]-2-azetidinone 4-as a starting material by using stereoselective hydrogenation and hydroboration, respectively. A practical synthetic route from 4 to the (3S, 4S)-4-[(R)-1-carboxyethyl]-3-[(R)-1-hydroxyethyl]-2-azetidinone derivative 1, a useful intermediate for the synthesis of 1β-metylcarbapenem antibiotics, was established.

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Two new gypsogenin glycosides, named lobatosides I and J, and one oleanolic acid glycoside, lobatoside K, were isolated from the seed of Actinostemma lobatum MAXIM. (Cucurbitaceae), and thier structures were elucidated to be as follows based on chemical and spectral evidence.Lobatoside I : 3-O-[O-β-D-galactopyranosyl-(1→2)-β-D-glucopyranosyluronic acid]gypsogenin 28-{O-β-D-glucopyranosyl-(1→3)-[O-β-D-xylopyranosyl-(1→4)]-O-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranosyl}ester.Lobatoside J : 3-O-[O-β-D-galactopyranosyl-(1→2)-β-D-glucopyranosyluronic acid]gypsogenin 28-{O-β-D-xylopyranosyl-(1→3)-O-β-D-xylopyranosyl-(1→4)-[O-β-D-glucopyranosyl-(1→3)]-O-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranosyl}ester.Lobatoside K is an oleanolic acid glycoside. The structure of the sugar moiety is the same as that of lobatoside I.

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The Diels-Alder adduct obtained from (E)-6-bromo-3-ethoxycarbonylmethylene-2-oxoindoline and trans-1, 3-pentadiene was successfully transformed into the diacetate of the aglycone of neosurugatoxin, which is the key intermediate in our first total synthesis of neosurugatoxin in 16 steps.

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New compounds designated talaroderxines A (1) and B (2) were isolated from a new heterothallic ascomycetous fungus, Talaromyces derxii, cultivated on rice. The structures of 1a and 1b were elucidated by means of spectroscopic examination and chemical reactions. Talaroderxines A (1a) and B (1b) are atropisomers of a 6, 6'-binaphtho-α-pyrone derivative, and have strong antibacterial activity against Bacillus subtilis.

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An alternative synthesis of the title compound 2, a highly potent analog of 1α, 25-dihydroxyvitamin D₃ (1), is described. Starting with 1α, 3β-bis[(tert-butyldimethylsilyl)oxy]androst-5-ene (8), 2 was obtained in 3.8% total yield through 10 steps. This method provides compound 2 in much higher yield than that reported previously.

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Three positional isomers of diglucosyl-cyclomaltohexaose (diglucosyl-cG₆) were chemically synthesized via 6¹, 6²-, 6¹, 6³-, and 6¹, 6⁴-di-O-(tert-butyldimethylsilyl)-cG₆s (1, 2, and 3) prepared regiospecifically. Glucosylation of bis(2, 3-di-O-acetyl)tetrakis(2, 3, 6-tri-O-acetyl)-cG₆s obtained from the three regioisomeric compounds 1, 2, and 3 with 2, 3, 4, 6-tetra-O-benzyl-1-O-trichloroacetimidoyl-α-D-glucopyranose, followed by debenzylaiton and then deacetylation, afforded 6¹, 6²-, 6¹, 6³-, and 6¹, 6⁴-di-O-(α-D-glucopyranosyl)-cG₆s (10, 11, and 12) together with configurational isomers. The desired compounds 10, 11, and 12 containing two (1→6)-α-linkages were isolated from the mixtures of their configurational isomers by high performance liquid chromatography. The three diglucosyl-cG₆s synthesized chemically were used as authentic samples to identify the components in a mixture of diglucosyl-cG₆s produced by an enzymatic process.

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Various (E)-hydroxystilbenes were synthesized from (E)/(Z) mixtures of methoxystilbenes through a new (Z)-(E) isomerization method followed dy demethylation. The nematocidal activity appears when methoxystilbenes are demethylated to hydroxystilbenes. For this activity, a hydroxy group at the C-2 or C-3 position is necessary. Thus, 2-hydroxy-, 3-hydroxy-, 2, 6-dihydroxy-, 3, 4-dihydroxy-, 3, 5-dihydroxy-, 2, 2'-dihydroxy-, 3, 3'-dihydroxy-, 3, 4'-dihydroxy-, 2-hydroxy-4-methoxy-, 5-hydroxy-2-methoxy-, 2-hydroxy-6-methoxy-, 6-allyloxy-2-hydroxy-, 3-hydroxy-5-methoxy-, and 5-allyloxy-3-hydroxystilbenes showed rather potent nematocidal activity. The activity of 5-allyloxy-3-hydroxystilbene was the strongest [minimal lethal concentration (MLC)=30 μM]. The activities of the (E) and (Z) isomers were comparable. The activities were also retained, though they were weaker, in the dihydro derivatives, hydroxybibenzyls.

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Palladium-catalyzed cross-coupling reaction of iodobenzene and its 4-substituted derivatives, except for 4-nitroiodobenzene, with (Z)-1-ethoxy-2-(tributylstannyl)ethene under a carbon monoxide atmosphere (5 atm) gave the corresponding (E)-3-ethoxy-1-arylprop-2-en-1-ones in considerable yields. Syntheses of chromone and 4(1H)-quinolinone were accomplished by application of this method to 2-(methoxymethoxy)iodobenzene and ethyl 2-iodophenylcarbanylate, respectively. The results obtained on the carbonylative coupling reaction of halopyridines are also described.

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The conformations of 4, 6α(H), 5β(H)-tetrahydro-α-santonin (4) and 4, 6α(H), 5β(H)-tetrahydro-β-santonin (5) have been determined by X-ray analysis and examination of the proton nuclear magnetic resonance spectra. The former has a non-steroidal form in the crystalline state, but changes the A-ring conformation in solution, while the latter takes a steroidal conformation both in the crystalline state and in solution. MM2 calculations support the above results.

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An oxygen-functionalization of the C₁₃-angular methyl group in 3β-acetoxy-5α-pregnan-20-one and its tetra-O-acetyl-β-D-glucopyranosyl derivative has been effected by means of an anodic oxidation mediated by the C₂₀-carbonyl residue in the steroid skeleton.

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Claisen rearrangement of an aryl propargyl ether in the presence of CsF led to exclusive formation of 2-methylarylfuran in excellent yield. The result of a precise examination of the rearrangement is described. Satisfactory transformation of the 2-methylarylfuran to a salicylaldehyde derivative was achieved by stepwise oxidation. This combination of reactions serves as a useful method for regioselective introduction of a C₁ unit at the ortho position of a phenol group.

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Sixteen kinds of chiral C4-epoxides [(-)-10a-d, (+)-10a-d, (-)-11a-d, (+)-11a-d], which are synthons in our synthetic strategy for complex lipids, have been prepared from (2Z)-2-butene-1, 4-diol (6) by employing a Sharpless asymmetric epoxidation. By using the chiral C4-epoxides [(+)-10a, (-)-10a, (-)-11a, (+)-11a] as starting compounds, two pairs of enantiomeric (D-erythro, L-erythro, D-threo, and L-threo)-C18-sphingosines (1, 2, 3, 4) have been synthesized via a regioselective ring-opening of the epoxide ring with azide anion followed by reduction of the azide group to an amino group and a Wittig reaction. Furthermore, D-erythro-C18-sphingosine (1) has been converted to a palmitoyl analogue (5a) of Gaucher spleen glucocerebroside (5) through a reaction pathway including successive condensations with palmitic acid and D-glucose.

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From a chiral C4-epoxide (-)-3, which is one of the synthons in our synthetic strategy for complex lipids, a glycerophospholipid C16-platelet activating factor (C16-PAF, 1) and a palmitoyl analogue (2) of an anti-inflammatory glyceroglycolipid M-5, which was previously isolated from the Okinawan marine sponge Phyllospongia foliascens, have been synthesized.

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A series of 75 imidazo[1, 2-α]pyrimidine derivatives were synthesized. The "in vitro" antibacterial activity of these compounds and their corresponding α-bromoketones against a variety of gram (+), gram (-) bacteria and Mycobacterium species is reported. Some of the prepared derivatives exhibited potent antimicrobial activity.

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A series of 2-alkoxy-2, 8-diazaspiro[4.5]decane-1, 3-diones and related compounds were synthesized and tested for muscarinic receptor binding affinity using [³H]pirenzepine and [³H]oxotremorine M as ligands. They were also evaluated for agonistic activities in the guinea pig ileum assay. 2-Methoxy-2, 8-diazaspiro[4.5]decane-1, 3-dione (1i) was found to be a relatively M1 selective agonist. It reversed CO₂-induced impairment of passive avoidance response with long duration of action, but also displayed peripheral effects at low doses. To minimize these side effects, we proposed the idea of conjugation of 1i with a muscarinic antagonist. The carbamate linked conjugate (1u) of 1i with methylatropine was therefore examined.

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Several N-substituted C-normorphinans (VIII and IX) were synthesized and tested for their analgetic and narcotic antagonist activities and physical dependence capacity. Treatment of N-formyl-octahydro-2-pyrindine (IIIc) with polyphosphoric acid readily gave N-formyl-C-normorphinan (IV). The N-nor bases (V and VII) obtained from IV were converted to VIII and IX. The N-methyl derivative (I), which was previously reported to be inactive by Haffner's method, exhibited potent analgetic activity by the hot plate method and the AcOH-induced writhing test. Compounds VIII and IX showed pharmacological properties similar to those of N-substituted morphinans and exhibited agonist (analgetic) and/or narcotic antagonist activities. The C-nor analogue (IXa) of cyclorphan (IIc) exhibited potent analgetic and antagonist activities with no physical dependence capacity in the single-dose suppression tests both in rats and monkeys.

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The structure activity relationship was studied in analogous lignans from Schisandra chinensis and their derivatives. These compounds were tested for cyclic adenosine 3', 5'-monophosphate (cAMP) phosphodiesterase inhibition. An inhibitor, nordihydroguaiaretic acid (13), was isolated from this plant, so we discussed this compound and a derivative, nordihydroguaiaretic acid tetramethyl ether, using molecular mechanics involving three-dimensional modeling and minimization of the structure using the MM2PP program. As a result, it was found that the structure of nordihydroguaiaretic acid tetrametyl ether and papaverine (30) (positive control) shared a similar low energy conformation. This fact suggested that these compounds inhibited cAMP phosphodiesterase by a similar mechanism.

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Hot aqueous extracts of medicinal plants were tested for their inhibitory effect on the binding of platelet activating factor (PAF) to rabbit platelets. The extracts of Forsythia suspensa VAHL. (Oleaceae), Arctium lappa L. (Compositae) and Centipeda minima (L.) A. BRAUN et ASCHERS (Compositae) showed significant activities. Since the main constituents of F. suspensa and A. lappa are lignans, 30 lignans were tested for their inhibitory effects on PAF binding to platelets and 9 lignans were found active. Four sesquiterpenes were isolated as active compounds from C. minima. In particular 6-O-angeloylplenolin and 6-O-senecioylplenolin are the most potent and specific PAF antagonists found in this study.

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The structure of 7-oxodihydrokarounidiol [7-oxo-D : C-friedo-olean-8-ene-3α, 29-diol], isolated from the seeds of Trichosanthes kirilowii (Cucurbitaceae), was determined by chemical correlation with karounidiol [D : C-friedo-oleana-7, 9(11)-diene-3α, 29-diol] from the same source. Two other natural products, viz. bryonolic acid (3β-hydroxy-D : C-friedo-olean-8-en-29-oic acid) and bryononic acid (3-oxo-D : C-friedo-olean-8-en-29-oic acid), were also correlated with karounidiol.

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The conformational studies of inulin oligomers from G-F₂ to G-F₉, which isolated from Platycodon grandiflorum, suggested a plausible conformational change between G-F₇ and G-F₈ from the trends in their chemical shift patterns and molecular rotation; the oligomers higher than G-F₈ would form some secondary conformations more rigid than shorter oligomers. On the other hand, spin-latice relaxation (T₁) studies of the protons proposed through-space interactions of 2- and 4-H's of glucose moiety in G-F₅, presumably with some atom(s) of the terminal fructose moiety. This would reflect that the inulin molecule adopts a 5/1 helix.

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Glycyrrhetic acid (GA), aglycone of glycyrrhizin (GL), inhibited potently (I₅₀=7×10^-6 M) and non-competitively the activity of NAD(P)⁺-linked 3α-hydroxysteroid dehydrogenase of rat liver cytosol. The inhibition was slightly weaker than that of indomethacin, a potent anti-inflammatory agent, but stronger than that of dexamethasone, another anti-inflammatory agent. GL, GA monoglucuronide, and 3-epi-glycyrrhetic acid also inhibited this enzyme activity, but did so less effectively (I₅₀=5-8×10^-5 M). Carbenoxolone (GA 3-hemisuccinate) and 3-keto-glycyrrhetic acid showed potent inhibitory effects similar to GA, and 18α-GA showed the most powerful inhibition of the activity.

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Two factors were separated from rat liver particulate fraction treated with insulin, one of them having a stimulating effect on low-K_m adenosine 3', 5' cyclic monophosphate (cAMP) phosphodiesterase activity of crude microsomal fraction (P-2 fraction) and the other having an inhibiting effect on the activity of low-K_m cAMP phosphodiesterase solubilized with 0.3% Brij 58 from P-2 fraction. Trypsin and heat treatments had essentially no effect on these two factors.The stimulating factor did not significantly change the apparent K_m value of enzyme in P-2 fraction but increased the maximal velocity of the reaction. The inhibiting factor raised the K_m value of solubilized enzyme without affecting the maximal velocity of the reaction.The stimulating factor level in diabetic rat was larger than that in normal rat while the inhibiting factor level in diabetic rat was smaller than that in normal rat. possible participation of both factors in insulin action is discussed.

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In order to investigate a possible role of lectin activity of ricin in its absorption from the small intestine, we prepared two ricin derivatives, BMH-ricin, prepared by crosslinking A and B chains of ricin with 1, 6-bismaleimidohexane, was nearly non-toxic but the lectin activity was unaltered. And, NBS-ricin, prepared by the oxidation of tryptophanyl residues of ricin with N-bromosuccinimide, was not only non-toxic but also non-lectinic.After the oral administration of ricin derivatives to rats, their interaction with the digestive tract and absorption into the circulatory systems have been compared with those of ricin, immunochemically and histologically. It was shown by immunostaining that ricin and BMH-ricin could bind to the intestinal mucosa, whereas NBS-ricin could not. No appreciable damage in the small intestine from rats treated with either BMH-ricin or NBS-ricin has been observed, in contrast to ricin treatment where severe impairment of the small intestinal tissues resulted after 5 h. Immunoreactive ricin in the liver has been determined with the ricin enzyme immunoassay (EIA). When compared at 48 h after oral administration, NBS-ricin was not detected, whereas BMH-ricin was found to be 38 μg/liver and ricin 100 μg/liver.From these results, it was inferred that the lectin activity of ricin plays an important role in the absorption of ricin from the small intestine and that the absorption of ricin protein was enhanced by its high toxicity.

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The antitumor activity of (1→3)-β-D-glucans was tested in order to clarify its conformation-dependent response together with conformational elucidation by carbon-13 unclear magnetic resonance (¹³C-NMR) spectroscopy. It was shown that the following three conformations, single chain, single helix and triple helix, are readily distinguished by the high-resolution solid-state ¹³C-NMR method. It turned out that preparations of linear (1→3)-β-D-glucans of a triple helical conformation were ineffective in the inhibition of tumor growth. These linear (1→3)-β-D-glucans were converted to an effective form in the inhibition of tumor growth when they were lyophilized from dimethyl sulfoxide (DMSO) solutions as a result of a conformational change from the triple helical to the single chain forms. They were not effective, however, when assayed in DMSO solution. In contrast, it was found that a branched (1→3)-β-D-glucan is effective not only in either saline solutions of the triple helical sample or the lyophilized sample from DMSO, but also in DMSO solution. The aforementioned drastic change in antitumor activity was interpreted in terms of resulting conformational changes as analyzed by the ¹³C-NMR method.

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Activation of the alternative pathway of complement (APC) and the Limulus factor G cascede by an alkali-soluble glucan, OL-2, isolated from a crude drug "leiwan" (Omphalia lapidescens) and its Smith-type degradation products were examined using human whole complement and Limulus lysate. OL-2 is a (1→3)-β-D-glucan having two branches at every third main chain glucosyl unit at each C-6 position (degree of branching (DB) : 2/3), and DB of the derivatives used in this study were OL-2-I (1/3), OL-2-II (1/2), OL-2-III (1/24) and OR-OL-2c (no branch : 0/1). Activation of APC by these glucans was dependent on incubation time and concentraiton. Under optimal conditions, OL-2-I, OL-2-II and OL-2-III showed stronger activation of APC than did the origical OL-2, and OR-OL-2c showed relatively weak activity. The structure-activity relationship of the activation of the factor G cascade was similar to that of APC. Considering the fact that the less branched derivatives of OL-2 also showed significantly stronger antitumor activity than OL-2, too much branching would suppress the recognition of (1→3)-β-D-glucan by the host-self defecse mechanisms.

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Acid phosphatase isozyme was highly purified from rat liver mitochondrial fraction. The enzyme showed an isoelectric point value of above 9.5 on isoelectric focusing, and the apparent molecular weight was estimated to be 32000 by Sephadex G-100 gel filtration or 16000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme catalyzed the hydrolysis of adenosine 5'-triphosphate, adenosine 5'-diphosphate, thiamine pyrophosphate, inorganic pyrophosphate, and phosphoproteion such as casein and phosvitin, but not of several phosphomonoesters, except for p-nitrophenyl phosphate and o-phosphotyrosine. The enzyme was not inhibited by L-(+)-tartrate, and was significantly activated by Fe²⁺ and reducing agents such as ascorbic acid, L-cysteine, and dithiothreitol. The enzyme was found to be distributed in various rat tissues including liver, spleen, kidney, small intestine, lung, stomach, brain and beart, but not in skeletal muscle.

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The gamma subunit of enolase (γ-enolase) was purified from the brain tissues of cow, dog, goat, pig, rabbit, and rat. The purificaiton was achieved in only three steps : ammonium sulfate-precipitation, DE 53 cellulose ion-exchange chromatography, and polyacrylamide gel electrophoresis (PAGE) in a preparative mode. The purification procedure was comparatively more simple than previously reported methods, and the yield of γ-enolase was sufficient for subsequent structural and immunological analyses. In all mammals, the purified γ-enolase migrated in sodium dodecyl sulfate-PAGE (SDS-PAGE) with a molecular mass of 46 kilodaltons (kDa), and the immunological cross-reactivity between those γ-enolases was very strong. The structural homology of these γ-enolases was examined by peptide mapping using cyanogen bromide cleavage and subsequent two-dimensional electrophoresis. The resulting peptide patterns were highly similar and in cow, dog, and goat, the patterns were almost identical. These results indicate that structural homology, that is, the species non-specificity of γ-enolase, appears to be very high.

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Water/oil/water emulsion (w/o/w emulsion) was prepared with liquid paraffin, a hydrophobic surfactant (Span 80) and a hydrophilic surfactant (Tween 20) by a two-step emulsification procedure. The percentage of solute entrapped in the inner aqueous phase and the viscosity of the emulsion system increased with an increase in the concentration of solute (glucose of sodium chloride) initially added to the inner phase of the emulsion. The oil membrane of the w/o/w emulsion, which entrapped the hypertonic inner aqueous phase, was thick, and the release of the solute from the emulsion was slow. The viscosity of w/o/w emulsion entrapping a hypertonic inner aqueous phase was large, and consequently, separation of the aqueous phase was delayed. A decrease in the encapsulation efficiency of w/o/w emulsion during storage was considered to be the result of a rupture of the oil membrane. Destruction of the w/o/w emulsion followed first-order kinetics. The rate constant of destruction of w/o/w emulsion at room temperature could be predicted by meauring the destruction rate at a higher storage temperature.

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The inhibitory effect of fluconazole (FCZ), a bis-triazole antimycotic, on mouse hepatic microsomal cytochrome P-450-mediated drug-metabolizing enzyme system was compared with those of ketoconazole (KCZ) in vivo and in vitro. Additionally, the change in the hepatic oxidative drug-metabolizing capacity in humans treated with FCZ was followed. The pentobarbital sleeping time in mice given a single dose of 1-10 mg/kg of FCZ or 30-50 mg/kg of KCZ was prolonged significantly, and the potency of FCZ for the prolongation of sleeping time was greater than that of KCZ. In contrast, in vitro the affinity and the inhibitory potency of FCZ for cytochrome P-450 and aminopyrine N-demethylation were 4- to 6-fold smaller than those of KCZ. However, the order of the inhibitory potencies among antimycotics for this enzyme system in vitro was reversed by the addition of albumin into the reaction mixture. These results indicate that the difference in the plasma protein binding properties between FCZ and KCZ is an important factor which leads to a reverse in the order of their inhibitory potencies for this enzyme system in vitro and in vivo. The ratio of 6β-hydroxycortisol (6β-OHF) to cortisol (F) in urine, used as an indicator of oxidative drug-metabolizing capacity in humans, decreased to 50% of the original level during treatment with 200 mg/d of FCZ. These findings indicate that the inhibitory effect of FCZ on hepatic microsomal cytochrome P-450-mediated drug-metabolism in vivo was unexpectedly potent from its potential obtained in vitro experiments in the absence of albumin, and that FCZ could be a potent inhibitor for hepatic oxidative drug-metabolism in humans.

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The effects of two kinds of cyclodextrins (CyDs), α- and β-CyD, on biological membranes were investigated by measuring changes in the absorption of a non-absorbable drug, sulfanilic acid (SA), from the rat small intestine, using in situ and in vitro experiments. After pretreatment with a mucolytic agent, N-acetyl-L-cysteine (N-Ac), only β-CyD increased the absorption of SA significantly compared to the absorption without pretreatment.The mechanism of the enhancing effect of CyDs on the absorption of SA was discussed. Almost no morphological change in the small intestine was observed by pretreatment with N-Ac alone, N-Ac or α- or β-CyD combinations. The liberation of membrane components differed among the CyDs, e.g., α-CyD selectively released phospholipid while β-CyD released mainly cholesterol from the intestinal membrane. It is suggested that the interaction of membrane components with DyDs may be at least partly responsible for the enhanced absorption of SA. Moreover it was found from in vitro electrophysiological experiment, that the alteration in enhanced permeability caused by β-CyD occurred primarily in the transcellular pathways, rather than in the paracellular pathways of the small intestine.These results suggest that the enhancement of intestinal absorption by β-CyD, after removal of the mucin layer from the intestinal surface, is due to the interaction between the membrane components and CyD. This interaction would induce disorder in cell membrane lipid, resulting in the increased permeability of the transcellular route.

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The effects of magnesium aluminum silicate (MAS) addition on the sorption of bromhexine HCl to polyethylene film in tablets were studied. The addition of MAS prevented the sorption of bromhexine HCl to polyethylene film. In order to investigate the mechanism, the interaction between bromhexine HCl and MAS was studied by the powder X-ray diffraction method. It was observed that bromhexine HCl was preferentially adsorbed to the surface of MAS rether than to polyethylene film.The adsorption was accelerated at high temperature and reduced pressure conditions. The sorption of bromhexine base and bromhexine HCl to packaging material were compared using tablet dosage forms. The sorption of bromhexine base to polyethylene film was greater than that of bromhexine HCl.

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Indomethacin-induced mucosal damage was assessed in vivo by measuring salicylamide (SAM) metabolism in rabbit intestine. Intestinal mucosal damage 48 h after oral indomethacin (500 mg/kg) administration was examined using a scanning electron microscope. Duodenal, jejunal and ileal mucosal toxicity was compared with that in controls. Intestinal first-pass metabolism of SAM was studied using in situ intestinal sacs with intact mesenteric venous blood collection. The appearance of both SAM and its metabolites in the mesenteric venous blood was measured following cannulation of the mesenteric vein of the exposed intestine and collecting all venous blood draining from the absording region. Following oral pretreatment with indomethacin, the appearance of SAM and SAM glucuronide (SAMG) in the mesenteric venous blood was significantly increased. The concentraions of SAM and SAMG in the blood increased following intraduodenal administration of SAM in vivo in rabbits orally pretreated with indomethacin compared with controls. However, after intravenous administration of SAM, the blood concentration of SAM and SAMG was not increased compared with controls. These findings suggest that the differences in intestinal first-pass metabolism of SAM may be due to the intestinal mucosal damage induced by oral indomethacin pretreatment. The results indicate that the alteration of intestinal first-pass metabolism of a marker compound may be utilized to assess intestinal mucosal damage in vivo.

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An oral administration of partially purified LPSw, a lipopolysaccharide (LPS) from wheat fluor, at a concentraion of 20 ng/ml in drinking water beginning 1 d after infection significantly decreased mouse mortality and prevented animal weight loss in acute infection with Toxoplasma gondii. Whereas 71% (5/7) of mice in a control group that did not receive LPSw died of toxoplasmosis, only 14% (1/7) of mice treated with LPSw died (p<0.05). The administration of LPS purified from Bordetalla pertussis also significantly decreased the mortality of infected mice. LPS from Escherichia coli and synthetic lipid A (LA-15-PP(506)), however, did not show a significant decrease in mortality.

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The effect of LPSw (a lipopolysaccharide from wheat flour) on cholesterol catabolism was examined using WHHL (Watanabe heritable hyperlipidemic) rabbit, which is an experimental model of familial hyperlipidemia. The serum cholesterol level of the animal decreased by the addition of LPSw to drinking water. Following cessation of the affition of LPSw to the drinking water, the cholesterol level was decreased for 30 to 40 d and then gradually elevated. The serum level of apolipoprotein B, which is a constituent of apolipoprotein of low density lipoprotein (LDL), also decreased in accord with serum cholesterol at a nearly coincident rate. Conversely, the level of apolipoprotein A-I, which is a constituent of apolipoprotein of high density lipoprotein (HDL), did not change, nor did HDL-cholesterol. Furthermore, the atherosclerosis risk factor, expressed as the ratio of apolipoprotein B to apolipoprotein A-I, was decreased by LPSw administration.

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The effect of LPSw (a lipopolysaccharide from wheat fluor) on the bone resorption of 18-d chick embryonic calvaria was examined in an organ culture following the method of Raisz. Bone was prelabeled in culture medium containing ⁴⁵Ca and chased in a cold medium. On addition of test smples, labeled calcium was released indicating the grade of bone resorption. LPSw (10-100 ng/ml) stimulated bone resorption, showing an effect comparable to parathyroid hormone (PTH) (1 U/ml). PTH at 1 U/ml decreased the total amount of calcium and phosphorus, while LPSw did not. LPSw is thus assumed to simulate bone resorption more actively than PTH.

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Oral administration of LPSw (a lipopolysaccharide from wheat flour) given at 60 μg/hen/d in drinking water, markedly enhanced eggshell strength. The monthly percentage of eggs laid with a shell strength of more than 4 kg to the total number of eggs was 32% in the group given LPSw in drinking water while it was 12% in the control group given plain water. At the same time, LPSw caused a 30% enhancement of total monthly number of eggs laid over that of control.

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Transfer selectivity to the blood and the lymph of exogenous dextrans of various average molecular weight (approximate 4, 10, 18, 39 and 70 kilodaltons (kDa)) after dosing to the subserosal layer of the rat stomach wall was investigated by measuring the fluorescein isothiocyanate labelled dextran concentrations in the lymph of the thoracic duct and the peripheral plasma. The lymph/plasma level ratio of the dextrans rose greatly with the increase in molecular weight (over 10 kDa) owing largely to the lower plasma concentration, although the lymph levels of small dextran (4 kDa) were not significantly higher than the plasma levels. These results indicate that there is an inverse relation between plasma levels of dextrans and their molecular weight, and also suggest that the molecular weight threshold of transfer selectivity of dextran to the blood and the lymph administered in the rat stomach wall is between 4-10 kDa.

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The relationship between the occurrence of side effects (SEs) and drug factors, such as antiepileptic drugs (AEDs), daily dose, duration of treatment, drug combination pattern, total and free serum concentrations, metabolite per parent level ratio as an index of metabolism ability, and co-medicated drugs except AEDs were evaluated in 227 outpatients with epilepsy. The possible influences of certain physiological and/or the pathophysiological factors were also evaluated. SEs with 19 clinical signs were observed in 66.1% of all patients. There was no definite dose- or serum concentration-dependent increase in the incidence of SEs. Stepwise discriminant function analysis revealed that benzodiazepines (BZN) polytherapy with AEDs produced a higher incidence of somnolence and general fatigue than did any other AED or drug combination. The effects of various drug combination patterns on the incidence of SEs were also evaluated on the basis of observed frequencies. The incidence of somnolence was significantly higher in patients taking phenytoin (PHT) plus carbamazepine (CBZ) therapy, and in patients taking BZN plus either PHT, phenobarbital (PB) or CBZ therapy compared with patients taking either PHT, PB or CBZ therapy. Other responsible drug combination patterns were PHT plus valproic acid (VPA) therapy for mental function impairment, acetazolamide (AZM) polytherapy with PB or PHT for dry mouth, and CBZ plus BZN therapy for constipation. In this study, the stratifying points (occurrence limits) of SEs were detected in various variables such as the number of prescribed drugs, daily dose and serum concentrations. Interestingly, these limits are within the commonly accepted "therapeutic range" or "usual daily dose, " and some of these limits shifted down when another AED was co-medicated. Furthermore, additional risk factors for patients who had clinical SEs, even though their serum concentrations or daily dose stayed below the limits, were evaluated. However, this study confirms that variables related to drug therapy are more closely involved in the occurrence of SEs than variable patient characteristics, especially the number of prescribed drugs and the AEDs polytherapy with BZN. The incidence of almost SEs (e.g. somnolence, weakness) significantly increased when three AEDs were co-medicated with BZN or AZM. Thus, it is emphasized that one or at most two AEDs, including psychopharmacological drugs, should be given to minimize the risk of SEs.

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The molecular behavior of flufenamic acid (FFA) was investigated in the physical and ground mixtures with two types of florite, florite R (FR) and florite S (FS). FR is mainly composed of porous calcium silicate while the main component of FS is porous silicon dioxide. The interaction of FFA and nonporous calcium silicate was also studied. Analyses were performed by differential scanning calorimetry, powder X-ray diffraction, and infrared-spectroscopy. Storage and grinding of the mixtures of FFA and FR resulted in the transformation of FFA to the amorphous ionic state, predominantly to calcium salt, and the amorphous state of the drug was found to be more stable in mixtures of higher FR content. In the mixture of FFA and FS, longer storage or grinding was necessary to obtain the amorphous state of FFA, and no change in its chemical state was observed. Differences of the FFA molecular state in the mixtures with FR and FS were attributed to differences of the chemical composition of these additives. Nonporous calcium silicate was found to have limited ability to induce transformation of FFA to the amorphous state as it has small surface area and lacks a porous structure. Stored or ground mixtures of FFA and FR showed marked enhancement in the dissolution behavior of FFA due to the existence of FFA in the amorphous ionic form.

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The pharmacokinetics of [6]-gingerol were investigated in rats with acute renal failure induced by bilateral nephrectomy, or those with acute hepatic faliure induced by a single oral administration of carbon tetrachloride (CCl₄), to clarify the contribution of the kidney and liver to the elimination process of [6]-gingerol. After bolus intravenous administration, a plasma concentration-time curve of [6]-gingerol was illustrated by a two-compartment open model. There was no significant difference in either the plasma concentration-time curve or any pharmacokinetic parameters between the control and nephrectomized rats. It is suggested, therefore, that renal excretion does not contribute at all to the disappearance of [6]-gingerol from plasma in rats. In contrast, hepatic intoxication with CCl₄ elevated the plasma concentration of [6]-gingerol at the terminal phase. Its elimination half-life increased significantly, from 8.5 to 11.0 min, in CCl₄-intoxicated rats. The extent of [6]-gingerol bound to serum protein was more than 90% and was affected very slightly by the CCl₄-intoxication. These aspects indicate that [6]-gingerol is eliminated partly by the liver.

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An attempt was made to isolate cancer cell lines from liver tumors that had been induced by aflatoxin B₁ (AFB₁) in rats. A clonal cell line named AFB-1 was isolated from a liver tumor that was histologically diagnosed as hepatocellular carcinoma. When AFB-1 cells were inoculated into the subcutaneous tissue at the dorsal region of syngenic animals, they metastasized from the site of inoculation into the abdominal cavity to form many tumor nodules throughout the serous membrane and metstatic foci in the kidney and pancreas. They also metastasized into the thoracic cavity to form metastatic foci in the lung. This is the first instance where a metastasizing AFB₁-induced cancer cell line has been isolated.

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The mutation of tyrosine 45 to tryptophan in ribonuclease T₁ enhances uncleolytic and binding abilities to its ligands [S. Nishikawa et al., Eur. J. Biochem., 173, 389 (1988)]. To examine the energetic and structural influence of this mutation in ribonuclease T₁, we made molecular dynamics and free energy perturbation calculations by converting the wild-type enzyme to the mutant one. The calculated difference of free energy changes following binding to 2'-guanylic acid (2'-GMP) molecule well agreed with experimental value. Between the mutant-2'-GMP complex and the wild-type-2'-GMP complex, subtle structural changes in stacking and hydrogen bonding interactions were found. Enhanced activity was almost entirely attributable to increased hydrophobic interaction between the ligand and the mutant enzyme. in the vicinity of ligand binding site, distributed water molecules revealed typical unordered structure around apolar atoms.

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We prepared test solutions which contained 80% (v/v) ethanol and 0.2% (w/v) chlorhexidine (CH) or benzalkonium chloride (BC) with or without a dibasic acid diester. After complete evaporation of the ethanol from the solution on filter paper, an overnight broth culture (Staphylococcus aureus) was repeatedly inoculated onto the filter paper, and viable bacterial counts were measured at 5 min after the last inoculation. By comparison with viable counts for CH or BC alone, we estimated the potentiating effects of dibasic acid diester on the bactericidal activity of CH or BC, and confirmed that this activity of the two disinfectants was potentiated in the presence of certain compounds in the homologs of di-n-butyl esters of aliphatic dibasic acid, and di-alkyl esters of adipic and phthalic acid. Diisobutyl adipate, one of the most effective diesters, substantially enhanced the bactericidal activities of benzethonium chloride, cetyl pyridinium chloride and didecyl dimethyl ammonium chloride, as well as CH and BC, but not those of polyhexamethylene biguanide or alkyldiaminoethyl glycinate. The potentiating effects of dibasic acid diesters observed for both CH and BC seemed to be affected by the hydrophobic character of these diesters themselves and are also expressed well by a particular quadratic equation as a function of these characters : namely, capacity factors, as determined by high-performance liquid chromatography.

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1-β-D-Arabinofuranosylcytosine (ara-C), an anticancer drug, has been isolated for the first time from a natural source, the mushroom Xerocomus nigromaculatus HONGO.

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The synthesis of 8-methylguanine 7-oxide (3) was accomplished via a "phenacylamine route", which started from condensation of α-(4-methoxybenzylamino)propiophenone (6), prepared by coupling of α-bromopropiophenone (4) and 4-methoxybenzylamine (5), with 2-amino-6-chloro-5-nitro-4(3H)-pyrimidinone (7) and proceeded through cyclization of the resulting phenacylaminopyrimidinone (8) and removal of the 4-methoxybenzyl group. The N-oxide 3 and its 9-arylmethyl derivatives 9 and 11 showed only very weak antileukemic activity and no antimicrobial activity.

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6, 7-Demethylenedesoxypodophyllotoxin (1) was isolated from the seeds of Hernandia ovigera L. (Hernandiaceae) collected in Taiwan, together with several known lignans. This is the first example of the occurrence of 1 in a natural source. The assignments of the ¹³C-nuclear magnetic resonance signals of several podophyllotoxin analogues isolated from this plant were also established by means of two-dimensional H-C correlation spectroscopy (COSY) and H-C long range COSY techniques.

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2-Substituted 6-, 7- or 8-methoxyquinoline-4-carboxylic acid derivatives were synthesized. The fluorescence quantum yield (Φ) of these compounds increased in the order, 2-thioxo-, 2-methylthio-, 2-methylsulfinyl-, 2-methylsulfonyl derivatives of 6-methoxyquinoline-4-carboxylic acid. Ethyl 6-methoxy-2-methylsulfonylquinoline-4-carboxylate (Φ_CH3CN=0.74 or Φ_EtOH=0.69) showed a much higher fluorescence quantum yield than those (Φ_CH3CN=0.19 or Φ_EtOH=0.19 and Φ_CH3CN=0.16 or Φ_EtOH=0.05) of the 7- and 8-methoxy derivatives in both acetonitrile and ethanol.

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