The oxidation of glucose to gluconic acid was carried out at 20°C in a membrane reactor in which a solution of glucose oxidase (EC 1.1.3.4) and catalase (EC 1.11.1.6) was entrapped between two semipermeable membranes of regenerated cellulose. A buffered solution (pH 5.5) of glucose saturated with oxygen was fed continuously through one grooved compartment outside the membranes (liquid side), and oxygen gas was supplied at a pressure slightly higher than 1 atm to the opposite grooved compartment (gas side). First, by holding one sheet of membrane between the two sides, experiments were performed to determine the membrane permeation coefficient for oxygen in the liquid (k_M) and the liquid-to-membrane mass transfer coefficient for oxygen in the liquid (k_L). The value of k_M was proportional to the difference between the gas-and liquid-side pressures and the value of k_L was proportional to the 0.56th power of the liquid flow rate. The reaction studies were done under conditions where the transfer of oxygen was a key process. From individual measurements of the absorption (permeation) rates of oxygen in the liquid through both membranes, it was found that, at low liquid flow rate, the transfer through the gas-side membrane contributed greatly to the global rate of absorption (reaction). For the mixing of enzyme solution, two models were considered ; the stagnant and mixing models. At low liquid flow rate, the rate data were well explained by the stagnant model. At high liquid flow rate, in contrast, the mixing model was applicable. The oxygen pressure and the membrane permeation coefficient were the most important factors affecting the global rate of reaction.

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The reaction of corticosteroid 17α, 21-cyclic ortho esters (2) with various chloroformates (3) afforded the corresponding 17α-acyloxy-21-chloro-21-deoxy derivatives (4) in good yields. It was found that several new derivatives, 17α-acyloxy-21-chloro-11β-hydroxy-6α-methyl-1, 4-pregnadiene-3, 20-diones (4a-g), exhibited potent vasoconstrictive activities.

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Mutaaspergillic and dl-hydroxyaspergillic acids, metabolites of aspergilli, were prepared by base-catalyzed hydroxylation of the corresponding 2-chloro-3, 6-dialkylpyrazine 1-oxides derived from DL-leucyl-valyl and DL-isoleucyl-leucyl anhydrides.

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The clear-cut separation of all of the secoiridoid glucosides of Swertiae Herba into acylated and unacylated glucosides fractions was achieved by solvent extractions of an aqueous suspension of the methanolic extract. The separation of all of the secoiridoid glucosides in both fractions was accomplished by high performance liquid chromatography (HPLC) on a reverse phase column, and the homogeneity of each peak was examined by means of field desorption mass spectrometry. The conditions for the quantitative analysis of these glucosides by HPLC and the application of HPLC to the analysis of the constituents of Swertia japonica and S. pseudochinensis are reported.

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Optically pure (1S, 1'S)-1-aryl-N-(1'-alkyl-2'-hydroxyethyl)-2-phenylethylamines (13-21) were synthesized from L-alanine, L-leucine, and L-isoleucine via (S)-2-aminoalkanols (1-3) and (E)-(S)-N-(1-alkyl-2-hydroxyethyl) arylmethylideneamines (4-12). On the other hand, the amines with (1R, 1'R) configuration (33-38) were synthesized from D-amino acids, i.e., D-alanine and D-leucine. The absolute configurations of these amines were confirmed by the aromatic quadrant-sector rule. The asymmetric reactions of chiral azomethines (7-12 and 30-32) with benzylmagnesium chloride were found to be extremely highly stereoselective. However, the reactions of the azomethines (4-6 and 27-29) derived from L- and D-alanine with the Grignard reagent afforded poor stereoselectivity.

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Nitrosation of 1, 3-diarylureas (Ia-f) with nitrosyl chloride or dinitrogen trioxide in dimethylformamide gave 1, 3-diaryl-1-nitrosoureas (IIa-f) in 59-96% yields, and nitrosation of 1, 3-diarylureas (Ia, c-f) with dinitrogen tetroxide also gave 1, 3-diaryl-1-nitrosoureas (IIa, c-f) in 75-91% yields. However, nitrosation of 1, 3-bis (4-methoxyphenyl) urea (Ib) with dinitrogen tetroxide in dimethylformamide resulted in the formation of 1-(4-methoxy-2-nitrophenyl)-3-(4-methoxyphenyl) urea (III) in 60% yield, and nitrosation with a large excess of dinitrogen tetroxide gave 1, 3-bis (4-methoxy-2-nitrophenyl) urea (IV) in 42% yield.

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The synthesis of the new heterocycles pyrrolo [1', 2' : 1, 2] pyrazino [6, 5-b] carbazoles was achieved by the intramolecular cyclisation of 2-(1-pyrrolyl) carbazole derivatives. These latter compounds were obtained by the Clauson-Kaas reaction starting from the corresponding 2-aminocarbazoles, obtained by reduction of 2-nitrocarbazoles. A study of this reduction has shown that the introduction of acetyl grouping in position 9 makes this reaction easier and gives better results than previous methods. ¹H-NMR spectra are studied.

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1, 2-Addition of organometallic compounds to the C-1 position of 2-benzoyl-3-chloro-2-cyclohexen-1-one is described.

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Thermolysis of 5-[(n-butylthio) methylene]-2-[2-(1-cyano-5-methoxybenzocyclobutenyl)-ethyl]-3-methylcyclopentanone (16) gave the tetracyclic compound (18) in excellent yield, and 18 was transformed into both the A-homograyanotoxane (3) and the phyllocladane (4) ring systems.

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Two new coumarins (9 and 10) and a new chromone (14), together with eight known coumarins (1-8) and three known chromones (11-13), which were identified by comparison with authentic samples, were isolated from the roots of Coelopleurum gmelinii (D.C.) LEDER (Umbelliferae). The structures of 9, 10 and 14 were established as 6-[(1R, 2S)-1, 3-dihydroxy-2-isovaleryloxy-3-methylbutyl]-7-methoxycoumarin, 6-[(1R, 2S)-2-angeloyloxy-3-β-D-glucosyloxy-1-hydroxy-3-methylbutyl]-7-methoxycoumarin (tert-O-glucosylangelol A) and (S)-7-β-D-glucosyloxymethyl-4-hydroxy-2-(1-hydroxy-1-methylethyl)-2, 3-dihydro-5H-furo [3, 2-g] [1] benzopyran-5-one (prim-O-glucosylangelicain), respectively.

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Racemization of the unwanted isomer (R-1) of (S)-(-)-5, 7-dihydroxy-1-(3, 4, 5-trimethoxybenzyl)-1, 2, 3, 4-tetrahydroisoquinoline (TA-073) via the imine 6 was examined. Reduction of 6 with NaBH₄ followed by hydrogenolysis over 10% Pd-C gave (±)-TA-073 in a good yield. Asymmetric reduction of 6 to S-4, the precursor of TA-073, by the use of the chiral reducing agent (I), prepared from NaBH₄ (1 eq) and (S)-N-benzyloxycarbonylproline (3 eq), was also investigated. Treatment of 6 with I in a halogenated alkane such as CHCl₂CH₃ or CHCl₂CHCl₂ at -30°C afforded S-4 in an excellent optical yield (87% e.e.).

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1, 6-Anhydro-2, 2', 3, 3', 6'- and -2, 2', 3, 3', 4'-penta-O-benzyl-β-lactoses (4 and 7) were synthesized from 1, 6-anhydro-2, 2', 3, 3'-tetra-O-benzyl-4', 6'-O-benzylidene-β-lactose (1). Condensation of 4 with 2, 3, 4-tri-O-acetyl-α-L-fucopyranosyl bromide (acetobromofucose) in the conventional Koenigs-Knorr reaction, followed by deacetylation, gave 4'-O-linked trisaccharide derivatives bearing α- and β-L-fucopyranosyl linkages (10 and 15) in 13.4 and 25.6% yields, respectively. Analogous condensation of 7 with acetobromofucose gave a 6'-O-linked, fully protected trisaccharide bearing a β-L-fucopyranosyl linkage (20) in 64% yield. Halide ion-catalyzed condensation of 7 with 2, 3, 4-tri-O-benzyl-α-L-fucopyranosyl bromide gave a trisaccharide derivative bearing an α-L-fucopyranosyl linkage (26) in 51.8% yield. Removal of the protecting groups of 10, 15, 20, and 26 provided the title trisaccharides (14, 19, 25, and 30). ¹H- and ¹³C-NMR spectral data of 14, 19, 25, 30, and synthetic intermediates are also presented.

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A new direct allylation of aromatic compounds has been developed. A mixture of allylsilane, allylgermane, or allylstannane and thallium (III) trifluoroacetate was allowed to react with an aromatic compound, a nucleophile, to give allylation product (s) in good yields via an allylcationic species. Thus, the usefulness of these allylmetal compounds as allyl cation equivalents was established.

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An efficient method for introducing a carbon unit at the α-position of alicyclic amines is described. The method involves the reaction of monocyclic or tetracyclic hexahydro-1, 3, 5-triazines with trichloroacetic acid, cyanoacetic acid, malonic acid and their derivatives, which are introduced into the α-position of amines in the decarboxylated form.

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Hydroxylation was shown to occur readily in the reactions of aromatic compounds such as benzoic acid, nitrobenzene, acetanilide, and phenol with ferrous ion-molecular oxygen in 0.5 M phosphate buffer (pH 6.8) at 40°C for 3 h. The yields of hydroxylated products were higher than those obtained with other reported hydroxylation systems of transition metalmolecular oxygen. The NIH shift was not observed in the title reactions of C (4)-deuterioacetanilide and C (4)-deuteriobenzoic acid. This system was also demonstrated to oxygenate caproic acid to give a mixture of 3-, 4-, and 5-oxocaproic acids in 67% total yield.

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The structure of sargatriol, a new phenolic compound containing an oxygenated isoprenoid component isolated from a brown alga Sargassum tortile, was elucidated to be 3 on the basis of spectral and chemical evidence. The absolute stereochemistry was established from the circular dichroism (CD) of sargatriol (3) and the shift reagent-induced CD of the methyl ether (4).

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The preparation of the title compound (1), a key intermediate for the synthesis of helenanolides (pseudoguaianolides with a C₁₀ α-methyl group), is described starting from the readily available enone (3). The correct stereochemistry of the C₁₀-metyl group was obtained because of the severe 1, 3-diaxial interaction in the perhydroindanone (5). The ring expansion of 5 by one carbon unit, the key step in our approach, was examined in three ways. Reaction of 5 with ethyl diazoacetate catalyzed by a Lewis acid was not highly regioselective, giving the perhydroazulenone (8) and (9) in a ratio of 1 to 4. Metal salt-catalyzed decomposition of the diazoester (10) produced only the β-ketoester (11). However, the desired ketone (8) was obtained by the rearrangement of the β-oxido carbenoid derivative from the dibromohydrin (12). Introduction of the Δ⁶-double bond into 8 for the conversion to 1 was achieved regiospecifically via kinetic enolization.

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Oxidative bond fission of β-alkanolamines, R¹R²C (OH) CR³₂NHR⁴ (group A amines) and R⁵-O-CH₂CH (OH)-CH₂NHR⁶ (group B amines) by chlorine dioxide was studied in buffer solution of pH 10, and the results were compared with those obtained by electrochemical oxidation of group A amines. No significant difference was found between the two groups of amines, and the fission mainly occurred at the C-N rather than the (α) C-(β) C bond except in the case of the amine in which R¹=phenyl. Chlorine dioxide oxidation, in general, caused more C-N bond fission than electrochemical oxidation did, and the reason for this is discussed.

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A highly regio- and stereoselective 1, 4-addition reaction of β-cyclopropyl-α, β-enones with an equimolar mixture of organocopper (I) and aluminum trichloride (RCu-AlCl₃) is described.

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In order to study the structure-activity relationship of sparsomycin, an antitumor antibiotic, 26 sparsomycin-related compounds (3-5) were synthesized and their antibacterial activities and lytic actions on Ehrlich ascites carcinoma cells were tested.

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QSAR analyses of rifamycin B amides and hydrazides were carried out, and the following equations containing the substltuent entropy constant, σ_s°, were obtained (the subscripts 1, 2 and 3 denote the substituent groups on the nitrogen atom). log (1/C)=-6.69 (±4.89) (Σσ_s°)²_{1, 2}+9.33 (±3.37) (Σσ_s°)_{1, 2}+5.54 where n=23, r=0.929, F=62.6, ** SD=0.34. log (1/C)=-6.00 (±1.70) (Σσ_s°)²_{1, 2, 3}+6.71 (±1.47) (Σσ_s°)_{1, 2, 3}+6.93 where n=17, r=0.950, F=64.4, ** SD=0.16.

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The inhibitory activity of flavonoids against L-phenylalanine ammonia-lyase [PAL ; EC 4.3.1.5] was systematically investigated. Twenty-three kinds of flavonoids were tested with three PAL preparations of different origins. Quercetin (8) was found to be the most active among the flavonoids tested and inhibited all three PAL preparations. Isoliquiritigenin (11), a biosynthetic intermediate of flavonoids, also showed relatively strong inhibition of PAL. However, the chalcone deactivated PAL in a time-dependent manner, and a model reaction with L-cysteine revealed that the chalcone formed an adduct with L-cysteine, indicating that PAL is deactivated by the Michael type addition of chalcone. The results obtained in this study suggest that the inhibitory activity of flavonoids against PAL does not occur by the mechanism of end product inhibition, as was suggested by Smith et al., but is merely a result of nonspecific deactivation of PAL.

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From the dried stems of Tinospora tuberculata BEUMEE (Menispermaceae), N-transferuloyl tyramine (1), N-cis-feruloyl tyramine (2), and a new phenolic glucoside, tinotuberide (6), were isolated. The structure of 6 was elucidated as 3-(4'-β-D-glucopyranosyloxy-3', 5'-dimethoxyphenylmethoxy)-2-trans-propen-1-ol.

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Eight esters (acetates and butyrates) of four phenolic naphthylazo compounds with sulfonic acid group (s) were synthesized and assessed as water-soluble chromogenic substrates for the assay of esterases. The absorption maxima of azo compounds produced enzymatically from these esters occur at wavelengths about 100 nm longer than those of the esters and their molar absorptivities are, higher than those of the esters. Investigations on the substrate specificities of these esters revealed, that all the esters are hydrolyzed by carboxyl esterase- and aryl esterase-mediated reactions, and butyrates of m-(4-hydroxy-1-naphthylazo) benzenesulfonic acid and Azorubin should be particularly useful as substrates for cholinesterase and aryl esterase, respectively.

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Ginsenosides Rb₁, Rb₂, Rc, Rd, Re and Rg₁ (GRb₁, GRb₂ and so on) isolated from the roots of Panax ginseng C.A. MEYER, and their 20S- and 20R-prosapogenins (S-PS and R-PS), 20S- and 20R-protopanaxadiols (S-PPD and R-PPD), and a mixture of 20S- and 20R-panaxadiols (SR-PD) at various doses were administered to rats intraperitoneally. Plasma corticosterone and glucose levels at 30 min after the administration were determined, and ED₅₀ values for corticosterone level were estimated. The ED₅₀ values of GRd, GRb₂, GRc and GRb₁ were 7.1, 20, 44 and 112μmol/kg, respectively. ED₅₀ of S-PS, the genuine prosapogenin of GRb₁, GRb₂, GRc and GRd, which has no sugar residue attached to the C-20 position, was 28μmol/kg, and the artifact prosapogenin R-PS also showed nearly the same activity, 26μmol/kg. The ED₅₀ values of genuine and artifact sapogenins S- and R-PPD were 42 and 32μmol/kg, respectively, but an epimeric mixture of two artifact sapogenins SR-PD showed no activity at a dose of 80μmol/kg. The ED₅₀ values of GRe and GRg₁, glycosides of 20S-protopanaxatriol, were 107 and >160μmol/kg, respectively. Most of these 11 compounds did not significantly affect the plasma glucose level at 30 min after the treatment.

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Activities of pyrimidine nucleoside phosphorylases were assayed in extracts of human tumors, normal tissues of the same organs and tumors of mice (Sarcoma-180) and guinea pigs (Line-10), with thymidine (dThd), uridine (Urd), and 5'-deoxy-5-fluorouridine (5'-DFUR) as substrates. The nucleoside cleaving activities were higher in extracts of human tumor tissues than in those of normal tissues of the same organs. In human tissues, phosphorolytic activitiy towards dThd was high, while that towards Urd was low. In animal tumors, Urd was the best substrate. 1-(2'-Deoxy-β-D-glucopyranosyl)-thymine (GPT), a specific inhibitor of uridine phosphorylase, inhibited the phosphorolysis of Urd and 5'-DFUR in extracts of animal tumors, but not that of dThd and 5'-DFUR in extracts of human tumors. A thymidine phosphorylase preparation was partialy purified from human lung cancer. K_m values of the preparation were 2.43×10^-4 M and 1.69×10^-3 M for dThd and 5'-DFUR, respectively. We conclude that in human tumors a thymidine phosphorylase activity converts 5'-DFUR to 5-fluorouracil, an activated form.

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Human liver glutathione peroxidase was purified to homogeneity by using acetone precipitation, ammonium sulfate precipitation, DEAE-cellulose column chromatography, Sephadex G-150 gel filtration, and ECTEOLA-cellulose, CM-Sephadex, and DEAE-Sephadex column chromatographies. Its homogeneity was confirmed by polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis. Human liver glutathione peroxidase contained 3.7 g-atoms of selenium per mole of enzyme. The molecular weights of the enzyme and subunit were 90000 and 23000, respectively. Glutathione peroxidase consists of 4 subunits with equal subunit molecular weight. The properties of human liver glutathione peroxidase were compared with those of human placental glutathione peroxidase which was purified by the same method. In an immunological study, placental and erythrocyte glutathione peroxidases both reacted with the antibody to human liver glutathione peroxidase.

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Hydrogen peroxide converted HbO₂ and DeoxyHb into MetHb, and MetHb into the complex [MetHbOOH], which readily regenerated MetHb. tert-Butyl hydroperoxide converted HbO₂ and DeoxyHb into MetHb, and MetHb into a complex which was rather stable. The formation of MetHb was mainly due to the direct action of each of these peroxides, and was influenced by the allosteric effector, IHP. Ascorbic acid affected the hydrogen peroxide-induced MetHb formation, probably due to hydroxyl radical produced during the interaction of ascorbic acid with hydrogen peroxide. HbO₂ and DeoxyHb treated with linoleic acid hydroperoxide at pH 7-8 produced MetHb in the presence of albumin or KCN. Complex formation between MetHb and linoleic acid hydroperoxide occurred at pH 8, and it was prevented by albumin and KCN. The reaction of MetHb with the hydroperoxide at pH 7 produced precipitates, and that at pH 7.4 yielded the complex and then precipitates. It was suggested that the interaction of MetHb with hydroperoxide first produced the complex, which regenerated MetHb with the production of some active species for cross-linking of hemoglobin tetramer upon treatment at a lower pH value or in the presence of albumin.

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Carboxypeptidases C_Ua and C_Ub were both inactivated with incorporation of 1 mol ³²P-labeled diisopropyl fluorophosphate per mol enzyme. The amino acid residue that reacted with this reagent was a serine residue in the active site of each enzyme. The amino acid sequence around this reactive serine residue was determined to be Glu-Gly-Asp-Ser-Gly-Gly-Glu-Leu for both enzymes by sequence analysis of three radioactive peptides isolated from partial acid hydrolysates of the ³²P-labeled enzymes.

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The concentrations of sugars, D-glucose, D-sorbitol, D-fructose and myo-inositol, and the activities of enzymes, aldose reductase and sorbitol dehydrogenase, which are associated with the sorbitol pathway, in the lenses of normal and alloxan-diabetic rabbits were determined. It has been demonstrated that the formation of sorbitol and fructose is accelerated and the level of myo-inositol is decreaed in diabetic rabbit lens. The concentrations of glucose, sorbitol, fructose and myo-inositol in normal rabbit lens were about 0.23, 6.5, 0.3 and 6.0μmol/g wet weight of lens, and those in diabetic rabbit lens were about 0.45, 29, 3 and 0.24μmol/g wet weight of lens, respectively. It has been suggested that the levels of aldose reductase and sorbitol dehydrogenase activities in whole lens are unaffected by diabetic conditions. However, we found that the distribution pattern in the lens of aldose reductase was different under normal and diabetic conditions. In the diabetic condition, the level of the enzyme in the outer zone including the capsule, epithelium and cortex, increased, and that in the nucleus decreased.

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In order to investigate the pharmaceutical availability of the water-insoluble glucan produced by Streptococcus mutans, application of the glucan as a filler for directly compressed tablets was studied. The fluidity of combined powder of glucan with lactose was determined and then the hardness and the disintegration properties of directly compressed tablets of these mixtures were studied in comparison with those of tablets containing microcrystalline cellulose (MCC). The fluidity of the powder mixture was not much improved by the addition of glucan to lactose. The hardness of tablets containing glucan was higher than that of tablets containing MCC over the concentration range used in this experiment (4-50%). However, the disintegration properties of tablets containing a large amount of glucan were inferior to those of tablets containing the same amount of MCC, as the disintegration took place immediately when the concentration of glucan was lower than 20% but was retarded gradually at glucan levels higher than 25%. The hardness of tablets containing glucan increased with increase in the compressional pressure, but the disintegration properties were not changed. Further, in the dissolution study of ascorbic acid (V.C.) from the tablets, immediate dissolution of V.C. was obtained and no inhibition of dissolution of V.C. by glucan was observed. Overall, these results suggest that the water-insoluble glucan may be practically useful as a filler for directly compressed tablets.

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The reaction of (+)-cyanidanol-3 with sodium sulfite in aqueous solution was investigated. (+)-Cyanidanol-3 was degraded by sodium sulfite in aqueous solution to afford a water-soluble degradation product, which was assumed to be (+)-cyanidanol-3 carrying the sodium sulfonate function in place of the aliphatic hydroxy group at the C-3 position. Further, it was found that the rate of degradation of (+)-cyanidanol-3 by sodium sulfite was approximately the same as that of epicatechin, that the rate was proportional to the concentration of sodium sulfite and to the sum of the concentrations of (+)-cyanidanol-3 and sodium sulfite, and that (+)-cyanidanol-3 or epicatechin was degraded more rapidly by sodium sulfite as the pH was increased. The activation energy of the degradation was calculated to be 28 kcal/mol at pH 8.0 from Arrhenius plots.

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An electrical device was introduced in place of a torsion balance in the vertical tensile strength method, and all forces applied to the surface of the powder bed were recorded automatically. The complex peaks of tensile stresses recorded for irregular particles were consistent with the interparticulate interactions discussed in the preceding report in relation to cohesiveness. The tensile strength between particles at various humidities was measured and the influence of environmental humidity on the cohesiveness of pharmaceutical powder is discussed. Hydrophilic and water-soluble powders showed an abrupt and large increase in cohesiveness with increasing humidity and a large amount of water was adsorbed in the vicinity of the critical relative humidity (R.H.). Hydrophilic and water-insoluble powders showed moderate changes of cohesiveness and amount of water adsorbed with increasing humidity. Some powders showed a progressive and exceptional increase of cohesiveness with increasing humidity due to swelling. A large amount of water was absorbed by such powders as starchs, silica gel, microcrystalline cellulose, and methylcellulose compared with other powders. Contact angle did not appear to be related to cohesiveness at various humidities. The slightly larger cohesiveness of hydrophobic powders than hydrophilic powders may have been a result of the irregular shapes of particles. The cohesiveness of particles became increasingly sensitive to humidity changes as the diameters of the particles was decreased, except in the case of water-insoluble powders.

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Noncrystalline cephalexin (NC) was prepared by freeze-drying of a saturated solution of the drug. The results of X-ray diffractometry and polarizing microscopy indicated that NC was in a noncrystalline state. The nuclear magnetic resonance spectrum and the thin-layer chromatography behavior of NC were identical with those of crystalline cephalexin (CC). NC was stored under 0-95% relative humidity (RH) at 35°C for 2 weeks. It absorbed about 1 mol of water at 20-32% RH, and about 2 mol of water at 43-66% RH, but there was no change in the X-ray pattern. When NC was stored at 75-95% RH, however, it absorbed more than 2 mol of water, and X-ray diffraction peaks appeared. This result suggests that NC was transformed into a partly crystalline state under conditions of 75-95% RH. The decomposition point (Dp) was measured with a differential thermal analysis (DTA) instrument. The Dp values of NC and CC were 173°C and 190°C, respectively. The Dp of the partly crystalline solid formed from NC under conditions of 75-95% RH was about 183°C. The solubility of NC in distilled water was examined by the equilibrium method. The amount of NC dissolved in distilled water at low temperatures reached a plateau, then decreased. This finding is due to the crystallization of NC. NC was about 6 times more soluble than CC solid at 10°C. The heat of solution for NC was calculated to be-3.24 kcal/mol from van't Hoff plots of log Cs versus 1/T.

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In order to investigate the reasons for the variation in the properties or the polymorphic transition behavior of semisynthetic fatty suppository bases, fatty acid composition, melting point, I_R value and the transition rate were measured for many kinds of commercial brands and batches. Then, the mutual relations of the above characteristics were examined. It was found that I_Rmax, the I_R value of the most stable crystal form, was correlated with both the melting point and the content of higher fatty acids such as stearic acid and/or palmitic acid. However, the transition rate did not show any special relation with I_Rmax, but was well correlated with the contents of lower fatty acids, such as caprylic acid and/or capric acid. These tendencies were also confirmed by the results of a fractionation experiment on Witepsol H-15, performed to investigate the above phenomena in more detail. In this experiment, it was observed that the X-ray diffraction pattern and I_R value of the physical mixture prepared from the fractionated samples coincided with those of the intact Witepsol H-15 in the cases of both stable and unstable crystal forms. These results suggest that the vehicle is constituted of many kinds of unit crystal cells differing in fatty acid composition, crystalline mode and physical properties. Thus, it was considered that the observed change of X-ray diffraction accompanying the A-to-B transition was mainly due to the higher melting point unit cells and that the transition acceleration was due to the lower melting ones.

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The effects of intraperitoneal treatment with hydralazine hydrochloride 5 mg/kg and phenobarbital 2.5 mg/kg daily for 7 d on the elimination of hydralazine (HP) and its acid-labile conjugates (ALC), on liver enzyme activities, and on hepatic and renal functions in both normotensive and spontaneously hypertensive rats (SHR) were studied. The rate constant (0.445±0.078 h^-1) for the elimination of HP from plasma in normotensive rats was significantly higher after the repeated treatment than that (0.205±0.085 h^-1) found in a single dosing study, while the rate constant after repeated treatment in SHR was only slightly higher (k=0.371±0.058 and 0.273±0.059 h^-1 for repeated and single administrations, respectively). The elimination of ALC from plasma was also enhanced by the repeated administration in both types of rats. Comparative i.v. injection of the combined drugs showed that the plasma HP concentration-time curve was biphasic and the terminal elimination rate constant of HP was almost the same as that for a single i.p. injection. The repeated dosing of the combined drugs significantly enhanced the drug-metabolizing enzyme activities in microsomes as compared with those of the control, but did not change the N-acetyltransferase activity of the liver. In normotensive rats, the repeated treatment of the combined drugs led to a significant increase in hepatic and renal clearance, whereas in SHR the same treatment had little effect. These results suggest that the difference in the plasma elimination of HP between normotensive rats and SHR was mainly due to the different extents of enhancement of hepatic and renal clearance following the repeated treatment.

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A simple microencapsulation of three sulfonamides (sulfanilamide, sulfisomidine and sulfamethizole) was investigated. The preparation is based on dispersion of a gelatinsulfonamide mixture in liquid paraffin, followed by drying and hardening with formalinisopropanol treatment. The microcapsules were recovered as a discrete, free-flowing powder with a particle diameter of 250-840μm. Dissolution of sulfamethizole from microcapsules approximated a zero-order release pattern from 0 to 10-30% dissolution. These microcapsules may be useful for studies related to sustained-release formulation.

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To evaluate the efficacy of gelatin microcapsules containing sulfonamides (sulfanilamide, sulfisomidine and sulfamethizole), blood concentration-time curves were obtained using gastric-emptying-controlled rabbits after intravenous or oral administration of powder and microcapsule dosage forms. Using the pharmacokinetic parameters derived from the intravenous study, the oral administration rate constant for sulfanilamide was calculated and the extent of bioavailability of the microcapsules was compared with that of the powder. It was very hard to obtain a significant advantage with regard to the prolongation effect in the gelatin microcapsules containing sulfanilamide. Similar result was also obtained in the case of sulfisomidine. However, prolonged and sustained release properties were clearly obtained with the microencapsulated sulfamethizole prepared by this method.

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Microencapsulation of three orally administered antibiotics (ampicillin, amoxicillin and cefalexin) was studied. Good reproducibility in microcapsule preparation was obtained, as in the case of the sulfonamides reported previously. In comparison with the release profile of ampicillin powder, sustained ampicillin release was observed from the microcapsules in the neutral medium. Gastric-emptying-controlled rabbits were used for the in vivo evaluation of microcapsules. No sustained release was observed from microcapsules of amoxicillin and cefalexin. However, the gelatin microcapsules containing ampicillin showed significant sustained release of ampicillin.

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The effect of probenecid on the plasma protein binding of sulfadimethoxine (SDM) was investigated in rabbits. Probenecid markedly reduced the in vivo binding of SDM to rabbit plasma proteins. On the other hand, probenecid had no effect on the in vitro binding of SDM to rabbit plasma proteins. Probenecid significantly increased N⁴-acetylsulfadimethoxine (N⁴-AcSDM) concentration in plasma after intravenous bolus injection of SDM, and prolonged the elimination half-life of N⁴-AcSDM after intravenous bolus injection of N⁴-AcSDM. In addition, N⁴-AcSDM reduced the in vitro binding of SDM to rabbit plasma proteins. These results indicate that probenecid indirectly reduces the in vivo binding of SDM to rabbit plasma proteins, by causing a significant increase of N⁴-AcSDM concentration in plasma.

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Magnetic guidance of magnetic emulsions with site specificity was investigated in vitro and in vivo. The emulsions consisted of ethyl oleate-based magnetic fluid as the oily dispersed phase and 1% casein solution as the aqueous continuous phase. The magnetic emulsion was characterized in vitro for magnetic responsiveness by using a constant flow apparatus, and its high retention by a magnetic field was confirmed. Ethyl oleate in the magnetic emulsion was labelled with ¹⁴C-palmitic acid and a selective localization of the magnetic emulsion at a predetermined site (lungs) by application of an electromagnet to the lungs was demonstrated. Such preferential localization by magnetic means suggested that this new carrier system can provide a highly specific delivery system for chemotherapeutic agents in cancer chemotherapy.

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Inclusion complex formations of spironolactone (SP) with three cyclodextrins (α-, β-, γ-CyDs) in aqueous solution and in the solid state were studied by the solubility method, by spectroscopic methods (UV, CD, IR) and by X-ray diffractometry, and their modes of interaction were assessed. The solid complexes of SP with β- and γ-CyDs were obtained in molar ratios of 1 : 2 and 2 : 3, respectively, and their dissolution, membrane permeation and oral absorption properties were examined. The rates of dissolution and permeation through a cellophane membrane in water were significantly increased by inclusion complexation (γ-CyD complex>β-CyD complex>SP alone), depending upon the solubility of the test samples. The serum levels of SP following oral administration of CyD complexes were found to be greater than those after administration of SP alone. The results indicated that the γ-CyD complex rather than β-CyD complex may have great utility as a faster dissolving form of SP able to produce higher serum levels.

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The pharmacokinetic charactor of ginsenoside Rg₁, one of the main saponins of ginseng (Panax ginseng C.A. MEYER), was investigated in rats by using thin-layer chromatography (TLC) and a dual-wavelength TLC scanner. Ginsenoside Rg₁ was absorbed rapidly from the upper parts of the digestive tract (accounting for 1.9-20.0% of the dose of Rg₁ administered orally). The serum level of ginsenoside Rg₁ reached its peak at 30 min, and the maximum levels of ginsenoside Rg₁ in tissues were attained within 1.5 h. However, ginsenoside Rg₁ was not found in the brain. Ginsenoside Rg₁ was excreted into rat urine and bile in a 2 : 5 ratio. It was also proved that ginsenoside Rg₁ was not significantly metabolized in the liver. However, the decomposition and/or metabolism of ginsenoside Rg₁ in rat stomach and large intestine were confirmed.

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A gas chromatographic-mass spectrometric (GC-MS) procedure using selected ion monitoring is described for the determination of chinoform (CF) and its two metabolites, glucuronide and sulfate, in plasma. The method consists of extraction of CF from plasma with pyridine-benzene (1 : 9, v/v) mixture containing 5-chloro-7-bromo-8-quinolinol as an internal standard, selective hydrolysis and extractions of the two conjugates, acetyl derivatizations and GC-MS analysis. The lower limit of CF quantitation by the present method was 3.3 pmol (1 ng) in 0.1 ml plasma volume. The method has sufficient sensitivity to permit pharmacokinetic studies with rats after single oral administration of CF.

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Previously, in order to clarify the mechanisms of the insecticidal action of streptothricin antibiotics, we had investigated the distribution of racemomycin-D into the tissues of the 5th instar larvae of silkworm, Bombyx mori, and reported that racemomycin-D accumulated in larger quantities for a longer time in the Malpighian tubules than in any other tissue. In this work, in order to clarify the mechanism of the insecticidal action in more detail, we investigated the Malpighian tubules of the larvae histopathologically and confirmed the occurrence of severe delayed damage. It is noteworthy that streptothricin antibiotics show strong nephrotoxicity in mammals. At 24 h after injection, which was the onset time of the damage to the Malpighian tubules, both the blood level and excretion amount of uric acid were increased, and they subsequently increased much further as the damage became more severe. Thus, through histopathologic examination and analysis of uric acid levels, we showed that the onset time of delayed toxicity of racemomycin-D in the organs of the insects was at 24 h after injection.

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Optically pure (3S)-1, 2, 3, 4-tetrahydroisoquinoline-3-carboxylic acid (1) was easily obtained by fractional crystallization of its benzyl ester (2b) p-toluenesulfonate, which was prepared from partially racemized 1 hydrochloride, followed by catalytic debenzylation. Similarly, (3R)-1 was prepared by the same procedure. The degree of racemization during the Pictet-Spengler reaction using optically active phenylalanine was determined by ¹H-nuclear magnetic resonance (¹H-NMR) spectroscopy of the corresponding methyl ester (2a), derived from the reaction product (1), in the presence of a chiral shift reagent.

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Lectin from tadpoles of Rana catesbeiana was partially purified by gel filtration on Sephadex G-75 followed by successive ion-exchange chromatographies on diethylaminoethyl (DEAE)-cellulose and carboxymethyl (CM)-cellulose columns. Since intact and enzymetreated erythrocytes showed no difference in agglutinability by the lectin, a β-galactosidebinding basic protein, this may indicate that the lectin recognizes glycolipid antigens rather than glycoprotein antigens of erythrocytes. In view of the lack of hemagglutinating activity with both acetylated and succinylated lectin, it is probable that amino groups are present in the visinity of the carbohydrate-binding site of the lectin molecule.

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The binding of 3', 4'-dideoxykanamycin B with a lysosomal enzyme, N-acetyl-β-D-glucosaminidase, obtained from rat kidney was examined by affinity chromatography of the enzyme on 3', 4'-dideoxykanamycin B-conjugated Sepharose 4B. N-Acetyl-β-D-glucosaminidase could be adsorbed on the affinity column. Furthermore, the enzyme activity was significantly increased by the addition of 3', 4'-dideoxykanamycin B. These findings indicate that 3', 4'-dideoxykanamycin B does interact with N-acetyl-β-D-glucosaminidase.

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Racemomycin-D showed strong delayed insecticidal action against the 5th instar larvae of silkworm, Bombyx mori. The pattern of toxic action was similar to that seen in mammals. In order to clarify the mechanism of insecticidal action of racemomycin-D, the authors investigated the distribution of racemomycin-D into the tissues of the larvae. In groups of larvae given various doses of racemomycin-D (50-200μg/g), the concentration of racemomycin-D in the blood decreased gradually in all cases, but the decrease rate was lower than that found in mammals. Racemomycin-D was not excreted in the feces. Racemomycin-D was accumulated in larger quantities for a longer time in the Malpighian tubules than in any other tissue. Change of color of the Malpighian tubules was observed visually. These phenomena resemble the findings in mouse and rat described in a previous report, namely, in the mammals, racemomycin-D was accumulated in large quantities for a long time in the kidney, and the organ turned white.

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The novel substituent entropy constant σ_s° represents the molecular connectivity _X, one of the QSAR descriptors developed by molecular topology. It is closely correlated with chromatographic retention data, such as retention time Rt or RT, and with retention index R.I. and specific retention volume Vg. Also, water solubility, boiling point and partition coefficient are represented by σ_s°.

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