^<13>C Nuclear magnetic resonance (¹³C-NMR) spectra were measured for polycyclic aromatic hydrocarbons (PAH) to examine the correlation between their chemical shift and carcinogenicity. We confirmed our previous proposition that the carcinogenicity of PAH molecules can be predicted from the value of the averaged ¹³C-NMR chemical shift. It was also found, using the averaged chemical shift as a parameter, that several quantum chemical indices for the intermediate states of the metabolic transformation are correlated with the carcinogenic activity of PAH. This indicates that the averaged chemical shift can be applied to investigate the metabolic transformation of carcinogenicity.

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Several derivatives of diltiazem (9a-c) have been synthesized from the oxamate (6) through the carbon-carbon ring closure of the sulfur-stabilized benzylic anion and the ester carbonyl group, followed by stereoselective reduction of the C₃-carbonyl of the 1, 5-benzothiazepine-dione (7).

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Five new saponins, ilexosides XV-XIX, were isolated from the fresh bark of Ilex crenata, and their structures were elucidated on the basis of chemical and physicochemical evidence. Ilexosides XV-XVII are 3, 28-bisdesmosides of siaresinolic acid, whereas ilexosides XVIII and XIX are those of pomolic acid.

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By utilizing newly developed synthetic methods i.e. 2-methylbenzofuran formation by CsF-mediated Claisen rearrangement of an aryl propargyl ether and its transformation to a salicylaldehyde by oxidative cleavage of the furan ring, total synthesis of a coctus alkaloid, lemaireocereine (2), was accomplished via ten steps from the aldehyde (4) in 22% yield.

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Five new hydrolyzable tannin dimers, roshenins A-E, and eight known tannins and related polyphenols [(+)-catechin, (-)-epicatechin, procyanidins B-3 and B-4, sanguisorbic acid dilactone, sanguiins H-2, H-6 and lambertianin A], have been isolated from the root of Rosa henryi BOUL. The structures of roshenins A-E (9-12, 19), which have a sanguisorboyl group as a linking unit between monomeric components, were established on the basis of spectral and chemical evidence.

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By taking advantage of our novel synthetic methods involving CsF-mediated Claisen rearrangement of an aryl propargyl ether to a 2-methylbenzolfuran and oxidative cleavage of the furan ring to a salicylaldehyde, total synthesis of chelerythrine, a benzo[c]phenanthridine alkaloid, was accomplished via the common intermediate (5) prepared through the two routes shown in Chart 3.

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Two new oxypregnane-oligoglycosides named calotroposides A (1) and B (2) have been isolated from the root of Calotropis gigantea (Asclepiadaceae), an Indonesian medicinal plant, and their chemical structures have been elucidated by chemical and spectroscopic methods as 12-O-benzoyllineolon 3-O-β-D-cymaropyranosyl(1→4)-β-D-oleandropyranosyl(1→4)-β-D-oleandropyranosyl(1→4)-β-D-cymaropyranosyl(1→4)-β-D-cymaropyranoside and 12-O-benzoylde-acetylmetaplexigenin 3-O-β-D-cymaropyranosyl(1→4)-β-D-oleandropyranosyl(1→4)-β-D-oleandropyranosyl(1→4)-β-D-cymaropyranosyl(1→4)-β-D-cymaropyranoside, respectively.

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1, 3-Dipolar cycloadditions of the C-aryl-N-alkylnitrones 2a-c and the C, N-dialkylnitrones 2e-g with the (E)-1-alkyl-2-nitroethenes 1a, b afforded predominantly or exclusively the cis-3-substituted 4-nitroisoxazolidines 3a-d and 3f-h. Exceptions are the reactions of C-phenyl-N-isopropylnitrone (2d) and C, N-diisopropylnitrone (2h) with 1a which gave the 3, 4-trans isomers 4e and 4i as the major products. These results can be rationalized in terms of secondary orbital interactions and steric effect.

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A novel glycosidation method has been developed which utilizes a trimethylsilyl halide-zinc triflate catalyst system to activate various benzyl-protected fucosyl, glucosyl and galactosyl esters. The promoter system was extended to use benzyl-protected alkyl glycosides and N-2, 2, 2, -trichloroethoxycarbonyl-protected glucosaminyl and galactosaminyl acetates as glycosyl donors.

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Besides previously reported hydrolyzable tannin oligomers (woodfordins A-D), a new hydrolyzable tannin monomer [isoschimawalin A (7)] and five oligomers (woodfordins E-I) have been isolated from the dried flowers of Woodfordia fruticosa (an Indonesian crude drug, Sidowaya), and their structures elucidated on the basis of spectra and chemical evidence. Woodfordins G (14) and H (15) were characterized as dimers with structures related to woodfordin B (2). Woodfordins I (16), E (23) and F (24) were a macrocyclic dimer, trimer and tetramer, respectively.

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Chiral and stereoselective synthesis of methyl (2R)-[(3S, 4S)-3-isopropenyl-2-oxoazetidin-2-yl]propanoate (14), a 3, 4-cis-β-lactam, was achieved starting from (-)-carvone.

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Three new compounds, (-)-epicatechin-5-O-β-D-glulcopyranodside (1), 5, 7-dihydroxychromone-7-O-β-D-glucuronide methyl ester (6), and a novel norcarotane sesquiterpene glucoside named marioside (7), have been isolated from the rhizomes of Davallia mariesii MOORE together with five known compounds, (-)-epicatechin-3-O-β-D-allopyranoside (2), coumaric acid-4-O-β-D-glucopyranoside (3), caffeic acid-4-O-β-D-glucopyranoside (4), vanillic acid-4-O-β-D-glucopyranoside (5), and L-tryptophan (8). The structures of the new compounds (1, 6, and 7) were determined by means of spectroscopic methods including two-dimensional nuclear magnetic resonance techniques.

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Two new phenylpropanoids named pongapinone A (1) and pongapinone B (2) were isolated from the bark of Pongamia pinnata (Papilionaceae), an Indonesian medicinal plant, and their chemical structures have been elucidated on the basis of their physicochemical properties. pongapinone A (1) was found to inhibit interleukin-1 production.

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The catalytic effect of various buffer systems (citrates, acetates, phosphates, borates and carbonates) on the degradation of SCH 29482 and FCE 22101 in aqueous solution was studied at 35°C and a constant ionic strength of 0.5 mol·dm^-3 over a pH range of 3.50 to 10.0. The observed degradation rates, obtained by measuring the remaining intact antibiotic, were shown to follow pseudo-first-order kinetics with regard to antibiotic concentrations and to be significantly influenced by general acid and general base catalysis. The changes in the concentration of intact SCH 29482 in the solutions were established by spectrophotometric determination of the reaction product with imidazole, while those of intact FCE 22101 were determined by reverse-phase high performance liquid chromatography with ultraviolet-detection. Of the buffer systems employed in the kinetic studies the borate one had the greatest catalytic effect. The pH-rate profiles for SCH 29482 and FCE 22101 showed a degradation minimum at pH 5.86 and 5.22, respectively. The SCH 29482 is more reactive with hydrogen ion than the FCE 22101 and less reactive with hydroxide ion. The Arrhenius activation energies were determined for SCH 29482 and FCE 22101 at pHs 4.23, 6.59 and 8.60.

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New 1, 4-dihydropyridine derivatives bearing a 4-(disubstituted phenyl) ring and an aminoethyl ester or an amino-2, 2-dimethylpropyl ester were synthesized and their antihypertensive activities were examined in normotensive rats and spontaneously hypertensive rats. The effects of phenyl substituents and ester groups on the antihypertensive activity are discussed. Several compounds showed a more potent antihypertensive activity than nicardipine and most compounds had a longer duration of action. Among them, 7B·HCI (TC-81) showed highly potent and long-lasting activity and was selected as a candidate for further pharmacological investigations.

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In order to improve the potency and duration of biological actions of diltiazem, a number of 1, 5-benzothiazepine derivatives having the substituents at the 8 position were prepared and evaluated for their antihypertensive activity in spontaneously hypertensive rats. The introduction of methyl, ethyl, isopropyl, benzyl, methoxy, ethoxy, phenoxy, and methylthio groups increased the antihypertensive activity and prolonged duration of action, whereas cyclohexyl, cyclopentoxy, tolyloxy, p-methoxyphenoxy and phenylthio derivatives were less active than diltiazem. Among them, the 8-benzyl and phenoxy derivatives showed the most potent and long-lasting antihypertensive action.

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A series of 2-alkylamino-5- or 6-aralkyl-substituted benzazoles were synthesized and tested for histamine H₂-receptor antagonist and anti-stress ulcer activities. These new compounds showed little or no histamine H₂-receptor antagonist activity in contrast to imidazo[1, 2-α]pyridine analogues (I). On antiulcer assay, however, some pyridine derivatives (II) exerted higher activity than the reference compounds, sofalcone, sucralfate and cimetidine. The structure-activity relationships of these compounds are discussed.

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The analgesic components were isolated from a Bornean medicinal plant, Tabernaemontana pauciflora BLUME (syn. Ervatamia blumeana MARK gr.), and the major components were identified as coronaridine and 3-(2-oxo-propyl)coronaridine. Four minor components were estimated to be 5R- and 5S-(2-oxopropyl)coronaridine, 3-(2-oxopropyl)voacangine and 3, 3'-(oxopropyl)dicoronaridine, which might be produced during the isolaion process. Voacangine was also isolated as a major component of T. pandacaqui POIR. Coronaridine and voacangine exhibited significant analgesic and hypothermic effects in mice at a dose of 25 mg/kg, p.o., while 3-(2-oxopropyl)coronaridine was less effective. The former two compounds also revealed a surface anesthesia.

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Pseudocarps or seeds of Rosa multiflora, crude drug "Eijitsu" ( ?? ?? ), have been used as purgative in Japanese traditional medicine. R. wichuraiana was generally thought to be able to substitute for the plant. The n-butanol fractions of both plant seeds were tested on purgative activities with mice, and the values of the 50% effective dose (ED₅₀) were 5.6 g/kg as the seed weight for R. multiflora and 57 g/kg as the seed weight for R. wichuraiana. From pseudocarps of R. multiflora, a new purgative compound, multinoside A acetate, was isolated, and its ED₅₀ value was tested to be 150 mg/kg (77-291 mg/kg, 95% confidence limit). The other isolated compounds were three known quercetin glycsides, quercetin 3-O-xyloside, isoquercitrin and hyperin. From pseudocarps of R. wichuraiana, three quercetin glycosides, isoquercitrin, hyperin and quercetin 3-O-β-D-glucuronide were isolated similarly, but no purgative components of R. multiflora were detected.

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The chloroform-soluble and n-butyl alcohol-soluble fractions of water extract of Pyrolae Herba inhibited platelet aggregation induced by arachidonic acid and showed a positive inotropic effect. A new naphthoquinone and a new tetralone derivative and known chimaphilin, acetovanillon, and toluhydroquinone were isolated as active constituents. Three new tetralone derivatives were also obtained from an active fraction. The structures of the new compounds were elucidated.

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Three new withanolides, physagulins A (1), B (2) and D (3), were obtained from the methanolic extract of the fresh leaves and stems of Physalis angulata L. (Solanaceae). Their structures were established as (20S, 22R)-15α-acetoxy-5β, 6β-epoxy-14α-hydroxy-1-oxowitha-2, 16, 24-trienolide (1), (20S, 22R)-15α-acetoxy-5α-chloro-6β, 14α-dihydroxy-1-oxowitha-2, 16, 24-trienolide (2) and (20S, 22R)-1α, 3β, 27-trihydroxywitha-5, 24-dienolide 3-O-β-D-gluco-pyranoside (3) by spectroscopic means.

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Six new complex tannins, guajavins A (5) and B (1), psidinins A (9), B (11) and C (13), and psiguavin (15), together with a variety of condensed, hydrolyzable and complex tannins, have been isolated from the bark of Psidium guajava L. (Myrtaceae). On the basis of chemical and spectroscopic evidence, the structures of guajavins and psidinins were established to consist of a (+)-gallocatechin unit and a hydrolyzable tannin moiety linked C-glycosidically, while psiguavin was found to be a novel metabolite probably derived from eugenigrandin A (7) through successive oxidation, benzylic acid-type rearrangement, decarboxylation and oxidative coupling of the gallocatechin B-ring and one of the aromatic rings in the hydrolyzable tannin moiety.

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Four lignans, blechnic acid (1), 7-epiblechnic acid (3), 8-epiblechnic acid (6) and brainic acid (2), were isolated from six Blechnaceous ferns, Blechnum orientale, Struthiopteris amabilis, S. niponica, Woodwardia orientalis, W. prolifera and Brainea insignis. Their structures were determined by spectroscopic methods and chemical conversion.

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A class of synthetic lignins (dehydrogenation polymers of p-coumaric acid, ferulic acid, and caffeic acid) inhibited cytopathogenicity of HIV-1 and HIV-2 infection. The ratio of cytotoxic to anti-HIV (human immunodeficiency virus) doses depended strongly on conditions during polymer preparation. The activity increased when polymers were treated with reducing agent NaBH₄, whereas it decreased when treated with oxidizing agent ceric ammonium mitrate. The polymers inhibited expression of HIV-specific antigen in the infected cells and also inhibited HIV-binding to the cells, but not completely, even at doses that almost completely inhibited the HIV-induced cytopathogenic effect. These results suggest that lignin structure, regardless of whether synthetic or natural, may inhibit HIV replication by an unidentified process, and thus prove to be a new class of anti-HIV agents possibly effective in the treatment of AIDS (acquired immunodeficiency syndrome).

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Attempts were made to prepare adsorbents having a high affinity for endotoxin in the culture supernatant of Bordetella pertussis. When poly(γ-methyl L-glutamate) (PMLG) was used as a matrix and amino groups as the ligand, the highest affinity for endotoxin was attained even at a high ionic strength (μ=0.2-0.4). PMLG beads containing amino groups of about 3.2 meq/g selectively removed endotoxin from the culture supernatant of B. pertussis without affecting the protective antigens. It was demonstrated that 1 ml of the wet adsorbent adsorbed 4.5 mg of endotoxin. The beads of PMLG derivatives, therefore, are considered to be a useful adsorbent for the removal of endotoxin from the pertussis vaccine, affecting neither filamentous hemagglutinin nor pertussis toxin.

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The effects of two polysaccharides, AT-HW and AT-AL obtained from the fruiting bodies of Armillariella tabescens on murine sarcoma 180 tumor and peritoneal macrophages were examined at intraperitoneal administration. AT-HW from the hot-water extract and AT-AL from the alkaline extract significantly inhibited the tumor, and the results of different administration schedule and phagocytic system blockade suggested that the mechanism of AT-AL differed from that of AT-HW and branched (1→3)-β-D-glucans. AT-HW and AT-AL showed reticuloendothelial system-potentiating activity, increased the number of peritoneal exudate cells, activated on macrophages (acid phosphatase activity, glucose consumption, superoxide anion production), and enhanced mitogenic reaction, although AT-HW did not produce superoxide anion in vitro.

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We examined the inhibitory activities of 3, 3'-dihydroxy-α, β-diethylstilbene (DDS) and 3, 3', 4, 5'-tetrahydroxystilbene (THS) on microtubule assembly in vitro and their effects on chromosome number and cellular microtubule networks in Chinese hamster V79 cells. DDS showed half the inhibitory activity of diethylstilbestrol (DES) on microtubule assembly in vitro, while THS had none of the inhibitory activity. DDS induced tetraploid at 30 μM, whereas THS was found to be inactive. Furthermore, DDS disturbed cellular microtubule networks at 100 μM.We also examined the effects of DES, DDS and THS on cellular actin networks in mouse BALB 3T3 cells. DES induced a change of actin stress fiber distribution and THS had similar activity, while DDS showed no activity.

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Effect of intravenously (i.v.) or intraperitoneally (i.p.) administered (1→3)-β-D-glucan, SSG, obtained from Sclerotinia sclerotiorum IFO 9395 on the murine peritoneal macrophage (PM) functions were examined. A single i.v. administration of SSG increased the number of PMs at a dose of 250 μg/mouse, and the peak appeared 4 d after administration. However, no special change was observed on peritoneal exude cell (PEC) populations. These PMs showed augmented lysosomal enzyme activity and the peaks appeared in 2 phases, on days 2 and 10. In contrast, SSG administered i.p. (250μg/mouse) increased the number of PMs and enhanced the lysosomal enzyme activity of PMs from day 4, and a broad peak appeared until days 8-12. The populations of PECs were also changed by i.p. injection of SSG. Additionally, SSG administered i.v. enhanced phagocytic activity, H₂O₂ production and interleukin 1 (IL-1) production, and the kinetics of the activation differed depending on the activities. These data suggest that the effects of SSG on macrophage functions are different depending on administration routes, and there are some different mechanisms in the activation of macrophages in vivo by SSG.

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The controlled Smith degradation and limited hydrolysis of glycyrrhizan UA, the main phagocytosis-activating polysaccharide isolated from the root of Glycyrrhiza uralensis FISCHER, was performed. The reticuloendothelial system-potentiating, anti-complementary and alkaline phosphatase-inducing activities of glycyrrhizan UA and its degradation products were investigated. Methylation analyses of primary, secondary and tertiary Smith degradation products and of the limited hydrolysis product indicated that the core structural features of glycyrrhizan UA include a backbone chain composed of β-1, 3-linked D-galactose. All of the galactose units in the backbone carry side chains composed of mainly α-1, 5-linked L-arabino-β-1, 6- or 1, 3-linked D-galactose residues at position 6. Removal of the arabinosyl side chains caused a pronounced decrease in immunological activity.

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Diets high in linoleate (safflower oil) or high in α-linolenate (perilla oil) were fed to rats for 11 months, and the effects of the diets on plasma and tissue lipids were compared. The plasma levels of total cholesterol (Cho), phospholipids (PL) and triacylglycerol (TG) were significantly lower in the high α-linolenate group than in the high linoleate group, the differences being more than 30% in the levels of total Cho and TG. The diets had differential effects on the lipid contents of major tissues : the TG level in muscle was higher but both the TG level in depot fat and the PL level in muscle were lower in the high α-linolenate group than in the high linoleate group. In order to clarify whether or not the hypolipidemic effect of the high α-linolenate diet was due to changes in the distribution of lipids among tissues, whole body lipids were estimated in mice fed these diets for 5 months. The whole body Cho content was significantly lower, by 28%, in the high α-linolenate group compared with the high linoleate group, but the total lipid content, PL and neutral lipids were similar between the groups. Our results indicate that the high α-linolenate diet has a more potent cholesterol lowering effect in plasma and body tissue than the high linoleate diet; interestingly, whole body TG levels are similar but tissue distributions of TG are different between the two dietary groups.

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The properties of phosphatidylinositol-specific phospholipase C (PI-PLC) from Bacillus thuringiensis were studied in detail. The enzyme was extremely thermostable in 0.1% bovine serum albumin and retained 73% of its activity at 100°C for 10 min, while it was labile in the absence of albumin. The enzymatic activity was inhibited by HgCl₂ or p-chloromercuriphenylsulfonic acid and restored by dithiothreitol. The kinetic parameters (k_m and V_max) of PI-PLC were determined for the mixed micelle of yeast phosphatidylinositol (PI)/Triton X-100 or sodium deoxycholate. Four PIs having different acyl chains : dilauroylphosphatidylinositol (DLPI), dimyristoylphosphatidylinositol (DMPI), dipalmitoylphosphatidylinositol (DPPI) and dioleoylphosphatidylinositol (DOPI) were synthesized from yeast PI through the processes of deacylation and reacylation, identified by infrared (IR) and Fourier transform nuclear magnetic resonance (FT-NMR) spectra, and subjected to the action of PI-PLC. All the syntheric PIs were hydrolyzed by this enzyme, with DLPI and DMPI being the best substrates. PI-PLC did not catalyze the hydrolysis of the phosphatidylnucleosides 5'-phosphatidylcytidine, 5'-phosphatidyluridine, 5'-phosphatidylthymidine, 5'-phosphatidyladenosine and 5'-phosphatidyl-2'-deoxyadenosine.

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Blue fluorescence with maxima at 350-370/420-440 nm produced by the non-radical reaction of amino groups of proteins with lipid peroxy (or alkoxy) radicals has been suggested to be derived from aldehydes other than malonaldehyde. Characteristics of fluorescence produced in the reaction of amino acids with aldehydes depended on the α-or ε-amino groups and on the unsaturation of the aldehydes. Unsaturated aldehydes, 2-hexenal and 2-octenal, produced fluorescence on ε-amino groups whose maxima at 360-380/430-460 nm were close to those produced by lipid radicals. Intensities of the fluorescence from lipid radicals and unsaturated aldehydes were similarly decreased in an alkaline solution and on borohydride treatment. The fluorescence formation from unsaturated aldehydes was enhanced by organic hydroperoxides without affecting the chromatographic profiles of the fluorescence. In the reaction of lipid radicals, it is suggested that lipid hydroperoxides from the radicals enhance the fluorescence formation from their degradation products, unsaturated aldehydes. Lipid radicals and 2-octenal formed cross-links in protein accompanying a similar decrease in lysyl and histidyl residues. Unsaturated aldehydes may be major causative molecules for protein damage by lipid radicals.

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Adenosine diphosphatase (ADPase) activity was solubilized with a non-ionic detergent, Tween 20, from human umbilical vessels and purified to homogeneity by diethylaminoethyl-Sepharose CL-6B, adenosine 5'-monophosphate-Sepharose 4B, and concanavalin A-Sepharose chromatography. The apparent molecular mass was 75 kDa. The purified enzyme hydrolyzed pyrophosphate bonds of nucleoside di- and triphosphates in the presence of calcium ion. It was insensitive to the adenosine triphosphatase (ATPase) inhibitors, oligomycin and ouabain, and sensitive to sodium azide. Therefore, we concluded that the ADPase activity in human umbilical vessels does not derive from ADPase degrading only ADP but from ATP diphosphohydrolase (EC 3.6.1.5). The broad substrate specificity and the sensitivity to various inhibitors and calcium ion are common to ATP diphosphohydrolase from bovine aorta. However, there might exist some structural difference around the active site, because the antiserum raised in rabbit against the bovine aorta enzyme acarcely inhibited the human umbilical enzyme.

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Alkaline sucrose density gradient and agarose gel electrophoresis methods were used to observe λ deoxyribonucleic acid (DNA) strand breaks by the reaction system of reduced glutathione (GSH) with alloxan in the presence of Fe³⁺-ethylenediaminetetraacetic acid (EDTA). When DNA was incubated in the reaction system for 10 min, DNA strand breaks were easily induced. The increasing concentrations of GSH up to 1.0 mM in the reaction system in the presence of 1.0 mM alloxan caused DNA strand breaks in a concentration-dependent fashion and GSH beyond 2.0 mM caused in the strand breaks of DNA by which the fragments with multiple ranges of molecular weight were produced. The strand breaks of DNA in the reaction system containing low concentrations of GSH were protected by catalase and hydroxyl radical (HO·) scavengers but superoxide dismutase (SOD) did not, indicating that such breaks were induced by HO· generated from the Fenton reaction. On the other hand, the strand of DNA at high concentrations of GSH were protected by ethanol and desferrioxamine, but not effectively by SOD and Ho· scavengers, suggesting the possible participation of some oxidizing species of iron rather than HO·. These results indicate that HO· or oxidizing species of iron generated in the GSH-alloxan system depending on the concentration of GSH attacks DNA to produce strand breaks.

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This report proposes an efficient in vitro method for the evaluation of drug targeting with monoclonal antibody as a carrier to tumor cells. Monoclonal antibody (35G; IgG_2a) selectively binding to α-fetoprotein (AFP) from human hepatoma cells (HuH-7) was conjugated with an anticancer drug, vindesine (VDS). Human tumor clonogenic assay (HTCA) with some modifications was applied to estimate the targeting efficiency of a conjugate (VDS-35G) for the first time. In this assay, VDS-35G was cytotoxically active against HuH-7 cells at a lower concentration (0.5 ng/ml) and for a shorter contact time than VDS (50 ng/ml), while 35G and VDS-normal mouse immunogloblin conjugate (VDS-n-IgG) were not active against the cells. Both VDS-35G and VDS-n-IgG were inactive against HuH-13 cells established from a human hepatocellular carcinoma producing no AFP. In the conventional monolayer culture assay (MCA), VDS-35G showed little effect on HuH-7 cells at the concentration effective in HTCA. The cytotoxic activity of VDS in MCA was similar to that in HTCA but the cytotoxic activity of VDS-35G in MCA was considerably different from that in HTCA. This discrepancy could be explained by the hypothesis that VDS-35G was directed at stem cells of the HuH-7 cell population sensitively and selectively. HTCA was shown to be a useful in vitro evaluation method for drug targeting.

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Dopamine (DA), which is ineffective by oral administration due to first pass metabolism and is usually injected, was administered to dogs via rectal, dermal, buccal and nasal routes. The nasal route had the highest bioavailability and best avoided first pass metabolism. The effects of the addition of hydroxypropyl cellulose (HPC), sodium deoxycholate, POE (6) hydrogenated caster oil (HCO-60) and Azone on the nasal absorption increased bioavailability from 11.7% (control) to about 20%, 35%, 25% and 68%, respectively.Further, with a combination of 2%HPC and 5%Azone, bioavailability was increased to almost the same level as with i.v. administration. At the same time, plasma concentrations were maintained at a high level for more than 7 h. The increase in bioavailability is presumed to be caused by an enhancement in absorption and prolongation of the time DA is retained in the nasal cavity due to Azone and HPC, respectively.

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A simplified model for computer simulation of agglomeration in the Wurster coating process was constructed using droplet size distribution and the relation between the size of agglomerates and the number of primary particles composing them experimentally determined. Computer simulations were applied to the cases where a 2.5% aqueous solution of hydroxypropyl cellulose (containing sodium carboxymethyl cellulose of 10% on a dry basis) was sprayed don four kinds of sharply fractionized lactose powders between 32 and 75 μm. With cores larger than 53 μm, the agitation exerted on particles strongly suppressed the growth of agglomerates, but the fraction of produced agglomerates reached about 50%. The smallest droplet size that was contributable to agglomeration (critical droplet size) was estimated to be 37.1-49.0 μm, increasing with core size, and the weight fraction of droplets larger than this critical size was only 0.5-2.7%, decreasing with increase in core size. The production of even such a minor amount of coarse droplets could be responsible for significant agglomeration.

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The fate of salicylic acid-glutamic acid conjugate (salicyl-glutamic acid) following oral, intravenous, intracecal and rectal administration (60, 10, 5 and 5 mg/kg, respectively : salicylic acid equivalent) was examined in rabbits. Salicylic acid was detected in the blood 2 h after oral administration of salicyl-glutamic acid and it reached the maximum level (69.4 μg/ml) at 18 h after the dose. A high blood concentration of salicylic acid (24.8 μg/ml) was observed up to 36 h. But only a small amount of salicyl-glutamic acid was detected in the blood (<2.5 μg/ml, as salicylic acid). In contrast, unchanged salicyl-glutamic acid was found mainly in the blood following intravenous administration of salicyl-glutamic acid, suggesting that presystemic de-conjugation of salicyl-glutamic acid predominantly occurred. The intestinal mucosal de-conjugation of salicyl-glutamic acid was negligible in the in situ intestinal sac preparation with complete mesenteric venous blood collection. Immediate and very extensive salicylic acid formation in the cecum was found following intracecal administration of salicyl-glutamic acid. After oral pretreatment of rabbits with kanamycin sulfate (6 × 400 mg), a significant inhibition of salicylic acid formation following intracecal administration of salicyl-glutamic acid was observed, indicating that the intestinal microorganisms were responsible for the biotransformation of salicyl-glutamic acid. Also, in vitro incubation of salicyl-glutamic acid with gut contents showed that the primary location of hydrolysis was the hind gut.

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The reactions of human serum albumin (HSA) with optically active amino acid p-nitrophenyl esters (substrate, S) were examined kinetically at 25°C. The rate data were analyzed in terms of a mechanism involving 1 : 1 complexing (S·HSA) between S and HSA. The dissociation constant (K_S in M) and the catalytic rate constant (k₂ in S^-1) of S·HSA were determined. Among ten substrates examined, the reactions with N-carbobenzoxy-D(L)-alanine p-nitrophenyl esters (N-CBZ-D(L)-AlaNP) were most accelerated by HSA. Results of the reaction in the presence of excess N-CBZ-D(L)-AlaNP over HSA indicated the existence of one strong reactive site on HSA. The effects of the reversible binding of the site-specific drug and the chemical modification by site-specific reagents on the HSA activity showed that the reactive site towards N-CBZ-D(L)-AlaNP is the R site located near tyrosine-411 residue of HSA.

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Percutaneous absorption of thiamine disulfide, (TDS), a lipophilic derivative of thiamine, from a mixture of propylene glycol (PG) and fatty acid (FA) or its analog through rat skin was tested in vitro. Lauric acid (12 : 0) enhanced the absorption depending on its concentation in PG and showed a maximal enhancement at 10% w/v. At 10% w/v, lauryl alcohol also enhanced the absorption, but less than 12 : 0, while lauric acid methyl ester suppressed the absorption. The flux of TDS did not depend on the solubility of TDS in the vehicle, but on the permeability coefficient. From these rsults, it is suggested that FA increases the permeability coefficient not only because FA increases TDS diffusion by disrupting lipid packing in the stratum corneum but also, FA increases TDS partition to lipid plase by interacting with TDS.

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In the present study, we examined the effects of methotrexate (MTX) on the development of autoimmune kidney disease in three kinds of autoimmune prone mice, NZB/NZW F1 (BWF1) mice, MRL/Mp-lpr/lpr (MRL/lpr) mice and NZW/BXSB F1 (WBF1) mice. The results showed that MTX delayed the appearance of proteinuria and prolonged survival of both BWF1 and MRL/lpr mice and inhibited the elevation of blood urea nitrogen (BUN) levels which accompanies the development of lupus nephritis. However, MTX treatment did not affect these in WBF1 mice. Furthermore, MTX could not suppress immunoglobulin G (IgG) class anti-deoxyribonucleic acid (DNA) and anti-trinitrophenol (TNP) antibody production in any variety of mice. These suggest that the therapeutic effect of MTX on BWF1 and MRL/lpr mice does not result in the suppression of IgG autoantibody production.

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Rat ascites hepatoma AH66 cells have lower sensitivity to Vinca alkaloids and anthracycline antibiotics than AH66F cells, a subline of AH66 cells. AH66 cells expressed P-glycoprotein, while the protein was not detectable in AH66F cells. There are two affinity sites for [³H]vinblastine binding in the AH66 cell membrane, while AH66F cells have only one affinity site. The high affinity [³H]vinblastine binding in AH66 cells was inhibited by Adriamycin, verapamil, nicardipine, and reserpine. The high affinity site of the binding may be the multidrug transporter, P-glycoprotein. [³H]Vinblastine binding was not influenced by adenosine 3', 5'-monophosphate (AMP), adenosine triphosphate (ATP), or guanosine triphosphate (GTP). The multidrug resistance in AH66 cells may depend on P-glycoprotein which is not modulated by nucleotide.

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Wohl-Ziegler bromination of 10-membered thiolcarbonates (3) gave regioselectively 7-bromocyclic thiolcarbonates (4). The structure of 4a was unambiguously established by an X-ray crystallographic analysis.

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Arylacetic acids, when the carboxyl group is at a secondary or tertiary carbon, are decarboxylated in considerable yields on irradiation of their aqueous alkaline solutions with 254 nm light, while the corresponding free acids are not decarboxylated. Together with the simple decarboxylation reaction (type A), two other side reactions, oxidative decarboxylation (type B) and decarboxylative dimerization (type C), were observed for some compounds, particularly when >290 nm light was used. The observation of high-yield decarboxylation of angularly substituted phenanthridone derivatives suggests that the above photodecarboxylation reaction would be a useful synthetic tool, if the substrate is appropriately designed.

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The water extract of Populus sieboldii MIQUEL (Salicaceae) inhibited arachidonic acid-induced platelet aggregation. Pyrocatechol and salicyl alcohol were isolated as active constituents. Pyrocatechol showed an inhibitory effect on platelet aggregation induced by arachidonic acid with IC₁₀₀ value of 4μM, which was 25 times more potent than aspirin.

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A novel chlorine-containing neo-clerodane diterpene, teupernin D, and two known compounds, teucvidin and teuflin, were isolated from the whole parts of Teucrium pernyi. The structure of teupernin D was characterized as (12S)-15, 16-epoxy-8β-hydroxy-17-chloro-19-nor-10α-neo-cleroda-4, 13, 14-triene-18, 6β : 20, 12-diolide on the basis of spectral evidence. The absolute configuration was established by the circular dichroism (CD) spectrum and confirmed by X-ray crystallographic analysis.

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A high-performance liquid chromatographic (HPLC) method for the determination of ornithine conjugation of some carboxylic acids in vitro has been developed. The ornithine conjugates of benzoic acid, p-nitrobenzoic acid, furancarboxylic acid and phenylacetic acid in an incubation mixture with kidney mitochondria were well separated on a reversed-phase C18 column using a mixture of 10 mM ammonium acetate buffer and methanol as the mobile phase. In addition, by varying the pH of the mobile phase and utilizing the absorption wavelengths (nm) of the conjugates it was possible to resolve and specifically detect each conjugate. The calibration curves were linear in the range of 0.2-16 μg/ml for all compounds and the detection limits were about 50 ng/ml except for the ornithine conjugate of phenyl acetic acid (S/N=2). The ornithine conjugatin of some carboxylic acids with chicken kidney mitochondria were determined by this assay method. The activity of ornithine conjugation of benzoic acid, furancarboxylic acid, p-nitrobenzoic acid and phenylacetic acid were 14.5, 5.5, 0.5 and 6.9 nmol/mg of protein, respectively. Moreover, the ornithine conjugation and the glycine conjugation of benzoic aicd were examined in birds and rodents. The ornithine conjugation was observed only in chicken (14.5 nmol/mg of protein) and mallard (0.99 nmol/mg of protein).

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A sensitive and specific double-antibody enzyme immunoassay (EIA) for a thyrotropin releasing hormone (TRH)-like immunoreactive substance has been developed. In order to synthesize TRH-labeled β-D-galactosidase (β-gal), a newly devised TRH derivative, pGlu-His-Pro-NH-(CH₂)₆-NH₂ (TRH-Hex), was employed. TRH-Hex was linked to β-gal by the N-(ε-maleimidiocaproyloxy) succinimide coupling procedure. For competitive reactions, the TRH antibody was incubated with standard TRH and TRH-Hex-β-gal (delayed addition). Free and antibody-bound enzyme hapten were separated by using an anti-rabbit immunoglobulin G coated immunoplate. Activity of the enzyme on the plate was fluorometrically determined. The present immunoassay allows detection of 0.8 to 100 pmol/well of TRH.

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A high-performance liquid chromatographic method with precolumn fluorescence derivatization using 2-(5-chlorocarbonyl-2-oxazolyl)-5, 6-methylenedioxybenzofuran is described for the quantification of 2', 3'-dideoxyinosine, a therapeutic drug for acquired immunodeficiency syndrome, and 2', 3'-dideoxyadenosine, an anti-human-immunodeficiency-viral agent, in rat plasma. The dideoxyribonucleosides and 3'-deoxythymidine (internal standard) in rat plasma (0.1 ml) are cleaned up by a solid-phase extraction technique using an octadecyl silica (ODS) cartridge, Toyopak ODS M, and the dideoxyribonucleosides in the eluate are reacted with the reagent to produce the corresponding fluorescent esters. The esters are separated by chromatography on a reversed phase column, TSKgel ODS-80T_M. The detection limits (signal-to-noise raito = 3) for the dideoxyribonucleosides are 1.3-5.4 pmol on column. Plasma concentrations of 2', 3'-dideoxyinosine after intra-jugular-vainous administration to rat can be monitored by this method.

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Numbers of functional groups introduced into horseradish peroxidase in reactions with four heterobifunctional reagents, S-acetylmercaptosuccinic anhydride, N-(ε-maleimidocaproyloxy)succinimide, N-succinimidyl 3-(2-pyridyldithio)propionate and N-(3-bromoacetamido-n-propionoyloxy)succinimide, were investigated. In the reactions at large molar ratios of the reagents to the enzyme in neutral and slightly alkaline media, maximum numbers of the incorporated functional groups were approximately 2.2 : two reactive amino groups are present in the enzyme molecule.

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