The conformation of semotiadil (1) was investigated by the molecular mechanics method. The analysis of energy components of the stable conformations suggested that stabilities are principally under the control of van der Waals and torsional energy terms. Two major van der Waals interactions were found between the 2-phenyl and the methylene-dioxyphenyl rings, and between the alkylamine side chain and the benzothiazine ring. The torsional energy term was caused mainly by the alkylamino side chain conformation. Stable conformations would be useful when considering possible solution conformations of 1.

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The synthesis of 7-[(3-N, N-dimethylamino)propylamino]-1, 4, 6, 11-tetrahydropyridazino[1, 2-b]phthalazine-6, 11-dione derivatives is reported. The expected monoalkylamino substituted derivative (4a) was obtained from the 7-chloro-substituted compound (3a), whereas the 7, 10-dichloro-substituted compound (3b) gave a mixture of the monoalkylamino derivative (4b) and the dialkylaminophthalimide (4c). The cytotoxic activity of 4a-c against HeLa cells was assayed. Compounds 4a and 4b showed a higher cytotoxicity than the starting adducts (3a and 3b).

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Zinc triflate was found to be superior to the heavy metal salts as a promoter in the Koenigs-Knorr type glycosidation reaction in the synthesis of lipid A disaccharide intermediates. It readily promoted the reaction of a complex glycosyl bromide with a reducing sugar moiety and gave the disaccharide with β-selectivity in good yield. This method would be suitable for the bulk preparation of lipid A disaccharide intermediates.

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The structures of several newly isolated anodendrosins, oxygenated derivatives of 4-O-glucosyl-3, 5-diprenyl-4-hydroxybenzoic acid ester with sucrose, dambonitol or glucose, from the seeds of Anodendron affine were elucidated by spectral methods.

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From the seeds of Asclepias curassavica, two cardenolides and twelve glycosides were obtained. Among these, four compounds were determined to be 16α-hydroxycalotropagenin, 16α-hydroxycalotropin and its 3'-O-glucoside and 3'-O-gentiobioside. Normally linked triosides of corotoxigenin, coroglaucigenin and 12β-hydroxycoroglaucigenin were characterized as cellobiosyl-allomethylosides.

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A new chiral 1, 3-bisphosphine, (1R, 2R)-1-diphenylphosphino-2-(diphenylphosphinomethyl)cyclopentane, which was designed to form the favorable skew conformation of the six-membered chelate with rhodium, was developed. Its rhodium complex was found to be one of the most efficient catalysts known for asymmetric hydrogenation of amino acid precursors. Further improvement of this ligand was also attempted for catalytic asymmetric hydrogenation of prochiral ketones to clarify the enantioselective mechanism.

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The alkaloidal constituents of the roots and aerial parts of Aconitum sanyoense NAKAI var. tonense NAKAI collected at Kuzure-sawa (Nagano prefecture) were reinvestigated. From the aerial parts, two new C₁₉-diterpene alkaloids, 10-hydroxyisotalatizidine (5) and 10-hydroxytalatizamine (7), were isolated along with five known diterpene alkaloids and two aporphine alkaloids. Three new alkaloids, i.e. 10-hydroxyisotalatizidine (5), 1, 15-di-O-acetylhypognavine (11), and 1-O-acetylhypognavine (12), were obtained from the roots in addition to eight known diterpene alkaloids. The structure of Hanamiyama base (14), found in the previous examination of this plant, was determined to be deacetyl-hanamisine.

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A new synthesis of 24-fluoro-1α, 25-dihydroxyvitamin D₂ (4a) and its 24-epimer (4b) is described. Starting with 1α, 3β-bis[(tert-butyldimethylsilyl)oxy]-24-norchol-5, 7-dien-23-al (5), a mixture of 4a and 4b was obtained in 3% overall yield in 6 steps. Reversed-phase HPLC cleanly separated the mixture into the two C-24 epimers. The X-ray crystallographic analysis of the 4-phenyl-1, 2, 4-triazoline-3, 5-dione (PTAD) adduct 11b, which was derived from the ester 6, unambiguously determined the configuration at C-24 of this compound. Based on the X-ray analysis, the configuration at C-24 of 4a and 4b was unequivocally determined.

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The dehydroellagitannins having a dehydrohexahydroxydiphenoyl ester group in the molecule were found to undergo highly regio- and stereospecific condensation with acetone in the presence of ammonium ion under almost neutral conditions. This reaction was successfully applied to high-performance liquid chromatographic analysis to detect the dehydroellagitannins in the plant extract. Furthermore, the reactions of the acetone condensates with L-cysteine methyl ester were examined, and appear to be applicable to structural studies of dehydroellagitannins.

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Optically active cerulenin 1, a potent inhibitor of fatty acid synthetase, was prepared via the condensation of the epoxy aldehyde 8 and the alkenyl lithium 16. In order to evaluate the effects of (E, E)-1, 4-double bounds of the cerulenin side chain on the interaction with the enzyme, a series of optically active cerulenin analogs 32a-i with modified side chains and tetrahydrocerulenin 3 were synthesized by similar procedures.

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2, 3-Epoxy-4-hydroxy-4-((E, E)-3, 6-octadienyl)cyclopentanone (dl-carbacerulenin 5) was synthesized via the epoxyketones 15a and 15b as a mimic of the active form of the antibiotics cerulenin 1, a potent inhibitor of fatty acid synthetase (FAS). The monobenzyl ethers (12 and 13), synthetic intermediates of 15, were prepared by direct benzylation of the epoxycyclopentene (7). Inhibitory activity of synthesized 5 toward yeast FAS was less than that of cerulenin by a factor of 1000.

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Tertiary tetraamines and quaternary pentaamines composed of aminopropyl and/or aminobutyl groups were synthesized as authentic samples for the identification of naturally occurring branched polyamines. Four tertiary tetraamines were obtained by alkylating the free secondary amine group of diphthaloyl derivatives of sym-norspermidine or sym-homospermidine with N-(3-bromopropyl)phthalimide or N-(4-bromobutyl)phthalimide in the presence of KF-Celite. Five quaternary pentaamines were obtained by fusing triphthaloyl derivatives of the tertiary tetraamines with an excess amount of N-(3-iodopropyl)phthalimide or N-(4-iodobutyl)phthalimide. The present methods are simple and achieved high yields. The ¹³C-NMR spectra of these branched polyamines were recorded in D₂O as fully protonated forms, and all ¹³C chemical shifts were assigned consistently.

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The quantitative structure-activity relationships (QSARs) of 37 carboquone derivatives with antileukemic activity and 51 benzodiazepine derivatives with anti-pentylentetrazole activity were studied using two neural computing methods-the functional-link net (FUNCLINK) and the generalized delta rule net with the back propagation of error(GDR). Both methods showed good fitting of the activity values in the two data sets. A great difference appeared, however, in the prediction of the activity values : GDR's predictive ability is much lower than FUNCLINK's. To elucidate the difference of the predictive ability, we examined the contribution of parameters to activity using the QSAR models of carboquone derivatives by plotting the contribution curves. Well-regulated and similar contribution curves resulted for all parameters in both the FUNCLINK and GDR models for the entire data. On the other hand, the contribution curves for the leave-one-out models derived by eliminating one compound from the data set showed that much greater deviations occurred in GDR than in FUNCLINK. The QSAR models of GDR seemed to depend greatly upon each individual compound.

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The methanolic extract of Swartzia polyphylla DC. heartwood had antibacterial activity against cariogenic bacteria, the mutans Streptococci. The chromatographic purification of the extract afforded seven flavonoids. Among them, three known isoflavanones, dihydrobiochanin A, ferreirin and darbergioidin, and one new isoflavanone, 5, 2', 4'-trihydroxy-7-methoxyisoflavanone (dihydrocajanin) had potent antibacterial activity against cariogenic bacteria. This effect was not detected on isoflavone derivatives. A comparative antibacterial study of various flavonoids was further performed, and their structure-activity relationship was discussed.

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Lagerstannins A (6), B (11) and C (8), ellagitannins having a gluconic acid core, have been isolated from the fruits and leaves of Lagerstroemia speciosa (L.) PERS. (=L. flos-reginae RETZ.)(Lythraceae). On the basis of chemical and spectroscopic evidence, their structures were established as 2, 3;4, 6-bis-O-(S)-hexahydroxydiphenoyl-D-gluconic acid (6), 2, 3, 5-O-(S, R)-flavogallonyl-4, 6-O-(S)-hexahydroxydiphenoyl-D-gluconic acid (11), and 5-O-galloyl-4, 6-O-(S)-hexahydroxydiphenoyl-D-gluconic acid (8), respectively. Furthermore, the structure of an ellagitannin, punigluconin, previously isolated from the bark of Punica granatum L., was revised as 2, 5-di-O-galloyl-4, 6-O-(S)-hexahydroxy-diphenoyl-D-gluconic acid (10), based on spectral re-examination.

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Two new steroidal glycosides, scopolosides I (1) and II (2), together with funkioside D (3) were obtained from the methanolic extract of the fresh underground parts of Scopolia japonica MAXIM. (Solanaceae) collected in Hiroshima prefecture, and the chemical structures of 1 and 2 were characterized to be (25R)-spirost-5-ene-3β, 15α, 23α-triol, named scopologenin (4), 3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside and scopologenin 3-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside, respectively, by spectroscopic and chemical evidence.

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Metabolites of antitumor cyclic hexapeptides, RA-VII and -X which were isolated from Rubia cordifolia were studied by hepatic microsomal biotransformation in rats and in bile juice of rabbits to which these drugs were administered intravascularly. Their structures and conformations were elucidated by two-dimensional nuclear magnetic resonance techniques, temperature effect on NH protons and nuclear Overhauser effect experiments. Specific N-demethylation of Tyr-3, O-demethylation and hydroxylation at aromatic rings of Tyr-3 and -5 were observed. Compared with metabolites of RA-VII, most of RA-X was excreted unchanged in the bile juice. Relationship among their structures, conformations and antitumor activities is also discussed.

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Three new oleanene glycosides, sophoraflavosides II-IV (2-4) were isolated together with sophoraflavoside I (1) as the corresponding methyl ester forms from Sophorae Radix, the fresh roots of Sophora flavescens AITON (Leguminosae). Their structures have been elucidated as oxytrogenin 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranoside (2), 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranosyl oxytrogenin 22-O-α-L-arabinopyranoside (3) and 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranosyl oxytrogenin 22-O-β-D-glucopyranosyl-(1→2)-α-L-arabinopyranoside (4), along with unambiguous characterization as 3β, 22β, 24-trihydroxyolean-12-en-29-oic acid for their sapogenol, named oxytrogenin (5) on the bases of chemical reactions and spectral analyses.

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From the bark of Robinia pseudo-acacia L., five new triterpene glycosides, robiniosides A-D (3, 5-7) and compound III (4), were isolated and their structures were elucidated as 3-O-α-L-rhammopyranosyl(1→2)-β-D-glucopyranosyl(1→2)-β-D-glucuronopyranosyl 3β, 22β-dihydroxyolean-12-en-29-oic acid (3), 3-O-α-L-rhamnopyranosyl(1→2)-β-D-galactopyranosyl(1→2)-β-D-glucuronopyranosyl 3β, 22β, 24-trihydroxyolean-12-en-29-oic acid (4), whose sapogenol was unambiguously characterized and designated as oxytrogenin, 3-O-α-L-rhamnopyranosyl(1→2)-β-D-gluco-pyranosyl(1→2)-β-D-glucuronopyranosyl oxytrogenin (5), 3-O-α-L-rhamnopyranosyl(1→2)-β-D-galactopyranosyl(1→2)-β-D-glucuronopyranosyl oxytrogenin 22-O-α-L-rhamnopyranoside (6), 3-O-α-L-rhamnopyranosyl(1→2)-β-D-gluco-pyranosyl(1→2)-β-D-glucuronopyranosyl oxytrogenin 22-O-α-L-rhamnopyranoside (7), respectively, together with two known triterpene glycosides, kaikasaponin III (1) and 3-O-α-L-rhamnopyranosyl(1→2)-β-D-galactopyranosyl(1→2)-β-D-glucuronopyranosyl 3β, 22β-dihydroxyolean-12-en-29-oic acid (2).

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A sensitive and specific high performance liquid chromatographic method for the determination of sulfide, sulfite, and thiosulfate was established. Inorganic sulfur anions were converted into fluorescent derivatives with monobromobimane. The derivatives were separated on a coupled column chromatography with a reversed-phase octadecyl silica column connected with a weakly basic anion exchanger column by isocratic elution with acetic acid solution (pH 3)-acetonitrile (13 : 3, v/v) containing 25 mM NaClO₄. The method was applied to the determination of bound sulfide and sulfite and thiosulfate in normal human serum. Thiosulfate could be determined directly by use of an ultrafiltered sample. For the determination of bound sulfide and sulfite, the pretreatment step with continuous flow gas dialysis was effective for the sample after releasing sulfide and sulfite by reduction with dithiothreitol. The limits of quantification by the present method were 0.05 μM for thiosulfate, 0.5 μM for bound sulfide, and 0.2 μM for bound sulfite.

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In this paper, we compared the chemical and biological activities of natural and synthetic clavamines, N-[2, 4-dihydroxyphenylacetyl-4-L-asparaginyl)-N'-[N-(L-arginyl-glycyl-L-alanyl)-8-amino-4-azaoctanoyl]-1, 5-pentane-diamine (DPA→Asn→Cad←Ptr←Ala←Gly←Arg)[DPA, 2, 4-dihydroxyphenylacetic acid; Cad, 1.5-pentanediamine (cadaverine); Ptr, 8-amino-4-azaoctanoic acid (putreanine, or carboxyethylputrescine)], and found that both were identical. Both compounds showed the same Rf value in thin-layer chromatography and the same retention time in high performance liquid chromatography (HPLC). Both hydrolyzates consisted of the same components, such as Gly, DPA, Ala, Asp, Arg and Ptr in gas chromatography. The Edman degradation of both compounds also gave exactly the same sequence. The ¹H-NMR spectrum and fast atom bombardment (FAB) mass spectrum of the synthetic compound coincided with those of the natural one. Both were active on the insects used. Clavamine was the main component of the insecticidal activity in the crude venom. By this synthetic study, the structure of a new venom insecticide was thus established. The synthetic compound in abundant quantity will be advantageous for practical use as an insecticide over natural ones, because the latter is available only in small amounts. Also, it will be useful for the exploitation of a new field of biochemistry for polyamines.

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The effects of bredinin on the primary culture of fetal mouse cells (fetal cells) and adult mouse lung cells (lung cells) were compared. Bredinin inhibited the growth of both cells, and this inhibition was found to be caused, at least in part, by the inhibition of the S phase and/or the transition from the G1 to S phase of the cell cycle. Bredinin inhibited both DNA and RNA synthesis without affecting protein synthesis. However, the inhibitory effect of bredinin differed between the two cell lines; the fetal cells were more sensitive than the lung cells, and bredinin inhibited DNA synthesis 100 times more potently in the fetal cells. The inhibition of DNA synthesis by bredinin in the fetal cells was gradually lowered by in vitro aging of the fetal cells to a level similar to that in the lung cells. There was no difference in the rate of incorporation of bredinin into the cells between the fetal cells and the lung cells. When fetal tissue was used as an enzyme source, bredinin was converted to bredinin 5'-monophosphate(BMP), but when lung tissue was used, bredinin was not converted. This is in agreement with the finding that bredinin has selective toxicity on fetuses in vivo but is hardly toxic to adult cells, which suggests the involvement of BMP in the selective toxicity of bredinin on the fetus.

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The anti-inflammatory profile of the analogues of bis(2-aminopropyl) disulfide dihydrochloride with butyl (compd. II) and phenyl (compd. III) instead of the methyl group was studied in several mouse models related to phagocyte functions. The test samples were administered 2-3 h before the inflammatory stimulation or the peak of inflammation.Subcutaneously administered, compds. II and III significantly inhibited serotonin-induced paw edema in a dose-dependent manner (50% inhibitory dose values : 10 and 5 mg/kg, respectively), when orally administered at 25 mg/kg, these compounds were significantly effective, but their potencies were weaker. Neither compound had any irritant activity when administered at a dose of 12.5 μg/5 μl/paw into the paw. In a sheep red blood cells (SRBC)-induced delayed-type hypersensitivity (DTH) reaction model, compd. II (25 mg/kg, s.c.) significantly inhibited the DTH responses when administered at two different times in relation to the time of challenge. However, there was only slight inhibition by compd. III (25 mg/kg, s.c.) on paw edema formation when administered 14 h after secondary immune response. In a model of experimental acute hepatic failure induced by successive injections of Propionibacterium acnes and lipopolysaccharide, both compounds increased mouse survived, compared with the control mice, and kept the serum levels of components involved in hepatic failure to nearly normal levels. These results demonstrate that compds. II and III possess an inhibitory effect on inflammation related to phagocytes.

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The immunosuppressive profile of Bacillus stearothermophilus UK563 component, Fr.5-B, is presented in in vitro studies. Fr.5-B (0.1-1000 ng/ml), provided it was added at the initiation of mixed leukocyte reaction (MLR), inhibited dose-dependently the incorporation of tritiated thymidine ([³H]TdR) into mouse spleen cells and human peripheral blood lymphocytes. Even the addition of Fr.5-B 48 h after the onset of culture suppressed mouse MLR, unlike cyclosporin A (CYA). Fr.5-B significantly inhibited cytotoxic T lymphocyte generation determined by [³H]TdR-release micro-cytotoxicity assay by using mouse mastocytoma P815 as targets. Moreover, this component decreased dose-dependently the expression of class II major histocompatibility molecules (Ia) on mouse peritoneal macrophages induced by concnavalin A supernatant. The present results revealed the unique immunosuppressive property of Fr.5-B which was different from that of CYA.

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Glycyrrhetic acid (GA), an aglycone of glycyrrhizin (GL), is a potent inhibitor of 11β- and 3α-hydroxysteroid dehydrogenases. 11β-Hydroxysteroid dehydrogenase activity of rat liver microsomes was potently inhibited by GA, 3-deoxyglycyrrhetic acid (3-deoxy GA), 3-ketoglycyrrhetic acid (3-ketoGA), 3-epiglycyrrhetic acid (3-epiGA) and 11-deoxoglycyrrhetic acid (11-deoxoGA), with I₅₀ values of 2-4×10^-7M. However, 18α-stereoisomers (I₅₀=3-7×10^-6M) of GA, 3-deoxyGA and 11-deoxoGA were one tenth less inhibitory on the enzyme activity than the corresponding 18β-isomers. On the other hand, 18α-stereoisomers of GA, 3-deoxyGA and 11-deoxoGA inhibited 3α-hydroxy-steroid dehydrogenase activity of rat liver cytosol more potently than the corresponding 18β-isomers. I₅₀ values of 18α- and 18β-isomers were 2 and 7×10^-6M, respectively, in the case of GA, 8 and 20×10^-6M in 3-deoxyGA, 3 and 20×10^-6M in 11-deoxoGA. These results indicate that the 18β-conformation of oleanane is important for the inhibition of 11β-hydroxysteroid dehydrogenase but on the contrary the 18α-conformation is important for the inhibition of 3α-hydroxysteroid dehydrogenase.

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An acidic polysaccharide, designated as cnidirhan AG, was isolated from the rhizomes of Cnidium officinale MAKINO. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 5.1×10⁴. It showed pronounced reticuloendothelial system-potentiating activity in a carbon clearance test, and had a remarkable effect on both anti-complementary and alkaline phosphatase-inducing activities. It is composed of L-arabinose : D-galactose : D-glucuronic acid in the molar ratio of 2 : 6 : 1, in addition to small amounts of O-acetyl groups. Methylation analysis, carbon-13 nuclear magnetic resonance, controlled Smith degradation and limited acid hydrolysis indicated that the core structural features of cnidirhan AG include a backbone chain composed of β-1, 3-linked D-galactose residues. Some of the galactose units in the backbone carry β-D-galactosyl side chains at position 6. Both α-D-arabinosyl arabinose side chains and terminal β-D-glucuronic acid residues are linked to the core galactan units.

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Tolbutamide (TBM) agglomerated crystals were prepared by three spherical crystallization techniques, the solvent change (SC) method, neutralization (NT) method and quasi-emulsion solvent diffusion (QESD) method (SC-A, SC-B, NT and QESD) agglomerated crystals), followed by mixture with a disintegrating agent and a lubricant (physical mixtures), and then tableting by the direct compression method. Unagglomerated TBM original crystals (bulk) were treated in the same manner. The dissolution rate and bioavailability of TBM from the physical mixtures and tablets were evaluated to look for a correlation between the in vitro dissolution profile and in vivo bioavailability.The TBM dissolution rate from the physical mixtures and tablets increased in the order of bulk≤QESD<SC-A<SC-B<NT in direct proportion to an increase in the specific surface area of the agglomerated crystals and bulk. A linear relationship could be established between the specific surface area and 75% dissolution time (T₇₅).In in vivo studies in beagle dogs, the physical mixtures and tablets of the agglomerated crystals showed significantly higher values than those of the bulk in the area under the curve of plasma concentration (AUC_0-8h), maximum concentration in plasma (C_max) and absorption rate constant (k_a), especially high values were obtained with the NT physical mixtures and tablets. A linear correlation could be established between 1/T₇₅ and k_a. The in vivo absorption process and bioavailability of TBM could be estimated from the in vitro dissolution profile.

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To achieve time-controlled or site specific delivery of a drug in the gastrointestinal tract, an orally applicable pulsatile drug release system with the dry-coated tablet form was developed. The system consisted of a less water permeable outer shell and a swellable core tablet; from such a system, the drug was expected to be rapidly released after a certain period of time on the basis of the time-controlled disintegration mechanism. Various model disks of outer shell, consisting of hydrogenated castor oil and polyethyleneglycol 6000, were tested for their water penetration rate. The experimental results showed that water penetration proceeded obeying the boundary retreating mechanism, so that the lag time of the system could be controlled by changing either the thickness or the composition of the outer shell. The swelling force of various commercially available disintegrants was quantitatively compared, and it was found that carboxymethylcellulose calcium was the preferable disintegrant to be used for the core tablet. On the basis of the results of a series of fundamental studies, various pulsatile release tablets of isoniazid with different lag times were designed. In the in vitro dissolution test, typical pulsatile release was achieved for all the tablets prepared, and a good correlation was found between the observed lag time and the estimated lag time calculated from an empirical equation deduced from the thickness and polyethyleneglycol 6000 content of the outer shell.

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The absorption of insulin (from porcine pancreas) from the rectum of rabbits after the administration of hollow-type suppositories containing insulin and five kinds of cyclodextrins (CyDs) was investigated. Three types of suppositories were employed : suppository I containing insulin (approximately 26 IU/mg) and various amounts of each CyD in citric buffer solution at pH 3.0 or powder in its cavity, suppository II containing CyD without insulin, and suppository III containing insulin without CyD. Without CyD, the insulin and glucose levels in plasma were unchanged, whereas a significant increase in the plasma insulin concentration and a marked decrease in the glucose levels were found following simultaneous administration of insulin and CyDs by suppository I. The enhancing effect of CyD on rectal insulin absorption (absorption-enhancing effect) by chemically modified CyDs (heptakis(2, 6-di-O-methyl)-β-CyD (DM-β-CyD) and 2-hydroxypropyl-β-CyD (HP-β-CyD)) was higher than those by natural CyDs (α-, β-, and γ-CyD). The area under the plasma concentration-time curve (AUC) and C_max of insulin significantly decreased with the preadministration (administration of CyD 6, 24 and 48 h before rectal insulin administration) of DM-β-CyD. The absorption-enhancing effect disappeared 24 h after preadministration. These results suggest that CyDs enhance insulin absorption from the rectum, and that attenuation of the membrane transport barrier function in the rectum recovers at a maximum of 24 h after administration of CyDs.

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The photo-stability of ethyl 2-[4, 5-bis(4-methoxyphenyl)thiazole-2-yl]pyrrol-1-ylacetate, KBT-3022 in aqueous solutions containing acetonitrile was investigated under the light of a high pressure mercury lamp. Its main photo-degradation product was assumed to be ethyl 5-hydroxy-5-[4, 5-bis(4-methoxyphenyl)thiazole-2-yl]-2-oxo-3-pyrrolin-1-ylacetate. KBT-3022 was also found to undergo ester hydrolysis by heat in both acidic and basic aqueous solutions, but its hydrolysis was confirmed to be negligible in the range of pH 3-9 at room temperature (25°C). Further, its photo-stability with exposure to the high pressure mercury lamp was comparable to that with exposure to a fluorescent lamp. Therefore, it is considered feasible to simulate the photo-stability of KBT-3022 in aqueous solutions containing acetonitrile by exposure to all other light sources including diffuse daylight, if the cumulative number of photons of the light can be determined by actinometry.

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The uptake of fractionated [³H]heparin was investigated in rat parenchymal hepatocytes in primary culture. The initial uptake of fractionated [³H]heparin was found to be saturable with the maximum uptake velocity (V_max) of 10.1±1.46 pmol/min/mg protein and the Michaelis constant (K_m) of 284±47.9 nM. The effect of α-globulin, the major protein binding to fractionated [³H]heparin, on the saturable uptake profile of fractionated [³H]heparin was also investigated. The uptake clearance was reduced, depending on the concentration of fractionated [³H]heparin, by the addition of 1 mg/ml α-globulin. We assumed that fractionated ³H-heparin bound to α-globulin was not available for uptake and that the reduction in the uptake clearance was solely attributable to the saturable binding of fractionated [³H]heparin to α-globulin. The uptake clearance versus concentration profile was analyzed to obtain the dissociation constant (K_d) of 31.8nM and the capacity (n) of 0.047 for the binding of fractionated [³H]heparin to α-globulin. The saturable binding of fractionated [³H]heparin to α-globulin was supported by in vitro binding experiments using gel chromatography, in which bound fractionated [³H]heparin decreased with the concentration of fractionated [³H]heparin in the presence of α-globulin. In conclusion, the present study demonstrated the saturable uptake of fractionated [³H]heparin by rat parenchymal hepatocytes and the saturable binding of fractionated [³H]heparin to α-globulin. The saturable uptake may suggest the involvement of a specific transport system such as receptor-mediated endocytosis.

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The thermal behaviours of hydrogenated egg lecithin (PC) and cholesterol (C) in anhydrous form and in aqueous dispersions were studied by differential scanning calorimetry. The role of C in phase transitions of C-PC mixtures prepared by physical mixing or coprecipitating from chloroform has been examined. C underwent a phase transition at 34°C and a second one at 76-78°C which depended on the thermal history of the samples. C lowered the gel to liquid crystaline phase transition temperature (T_t) of the aqueous dispersions prepared from C-PC coprecipitates, broadened the endothermic peak at the T_t, and at 1 : 1 molar ratio the C-PC system did not undergo the phase transition. The C-PC interaction was observed below the T_t. In aqueous dispersions prepared from C-PC physical mixtures, C did not influence the phase transition and acted like an inert diluent. Pellets prepared from C-PC mixtures formed myelin bodies as a result of their erosion in 0.185M borate buffer (pH 7.4) at below T_t, but the thermal behaviours of these myelin bodies were different for pellets prepared differently. Addition of bovine serum albumin (BSA)(10%, w/w) to the physical mixtures or coprecipitates of C-PC, or to PC alone did not show any effect on the thermal behaviours of their aqueous dispersions at the T_t.

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It was found that the differences between the frontier molecular orbital energies (ε_homo-ε_lumo=Δε) in polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) have a correlationship with the magnitude of the biological activity which is influenced by both the number and position of chlorine atom substituents on PCDFs and PCBs skeletons. Moreover, it was found that the Δε's values of PCBs are classified into two types which coincide with the well-known classification of PCBs to types of 3-methylcholanthrene and phenobarbital according to their biological activities.The relationship between Δε and biological activity in these xenobiotics suggests that the congeners having small Δε values such as 2, 3, 4, 7, 8-pentaCDF, 2, 3, 4, 6, 7-pentaCDF, 3, 4, 5, 3', 4'-pentaCB, and 3, 4, 5, 3', 4', 5'-hexaCB form stable molecular complexes with an Ah-receptor, e.g. (2, 3, 4, 7, 8-PentaCDF-Ah-receptor), while the congeners having large Δε values are strongly suggested to be unstable in a complex formation. Thus, this work presents an explanatory method to help understand the structure-activity relationship of the xenobiotics PCDFs and PCBs.

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4-(N, N-Dialkylamino)-2-phenyl-2-(2-pyridyl)butanenitriles (10, 11 and 12) and 5-(N, N-dimethylamino)-2-phenyl-2-(2-pyridyl)pentanenitrile (13) react with ethyl chloroformate, via a cyclization-N-dealkylation process, to give indolizinium and quinolizinium salts (1 and 2). Compounds 1 and 2 are also obtained by reaction of the alcohol derivatives 14 and 15 with thionyl chloride. Reaction of 2-phenyl-2-(2-pyridyl)ethanenitrile (9) in the presence of potassium hydroxide in dimethyl sulfoxide, leading to [2-hydroxy-2-phenyl-2-(2-pyridyl)ethyl]methylsulfoxide (21), is also described.

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Five β-ketoalkyl 2-(1-dimethylaminoethyl)phenyl sulfoxides (2a-e) were prepared by lithiation at the α-methyl hydrogen to the sulfoxide group of N, N-dimethyl-1-(2-methylsulfinylphenyl)ethylamine (1), followed by condensation with esters. The reduction of 2a-e gave two kinds of β-hydroxysulfoxides (3a-e and 4a-e), whose structures were determined by transforming 4a to naturally occurring (-)-matsutakeol. The results on the diastereoselectivity of this reduction and the ¹H-NMR spectral behavior of the α-hydrogens to the sulfoxide group were different from those found in the case of reduction of β-ketoalkyl tolyl sulfoxides.

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The transformation of 3-acetyl-2-azetidinone into 3-[(R)-1-hydroxyethyl]-2-azetidinone was achieved by highly stereoselective reduction with N-benzylaminoethoxyborane in the presence of trifluoroborane etherate. The combination of this reduction method and optical resolution using l-norephedrine provides a practical synthetic method for (3S, 4S)-4-carboxy-1-(di-p-anisylmethyl)-3-[(R)-1-hydroxyethyl]-2-azetidinone, which is a key intermediate in the synthesis of carbapenem and penem antibiotics.

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Effects of seven limonoids, obakunone (1), 7α-obakunol (2), 7β-obakunol (3), limonin (4), 7α-limonol (5), 7β-limonol (6) and nomilin (7), on the sleeping time induced in mice by anesthetics were assayed.All the limonoids, except for 2, shortened the sleeping time induced by α-chloralose and urethane. 7 gave the highest reduction rate of sleeping time, and the order of the reduction rate of sleeping time was as follows; 7>1 and 3>4, 5 and 6.As the chemical structures of these compounds are similar to each other, the relationship between the structure and the effects of limonoids on sleeping time was discussed.

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Two new glycosides, termed as flavoplatycoside (1) and grandoside (2), respectively, have been isolated from the seeds of Platycodon grandiflorum A. DE CANDOLLE (Campanulaceae) and their structures have been established as (2R, 3R)-taxifolin 7-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside and 3-methyl-1-butanol 1-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranoside, respectively, based on chemical and spectral evidence. Four known flavonoids, (2R, 3R)-taxifolin (3), quercetin 7-O-glucoside (4), luteolin-7-O-glucoside (5), and quercetin 7-O-rutinoside (6), were also isolated.

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Tryptophan (Trp) residues involved in the binding of 1, 1, 1-trichloro-2, 2-bis(4-chlorophenyl)ethane (DDT), 2, 2-bis(4-chlorophenyl)ethane (DIM) and dichlorobenzophenone (DCBP) by Rhizopus delemar C-lipase were identified on the basis of knowledge of amino acid sequences around the Trp residues. Eight Trp- or modified Trp-containing peptides were isolated from each of 1 : 1, 2 : 1 and 9 : 1 pesticide-lipase complexes modified by 2-hydroxy-5-nitrobenzylation under three different conditions, and the peptides were identified.The results confirm the previous tentative assignment of the Trp residues involved in the ligand binding, which was presented on the basis of comparison of their modification patterns.

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A hydrogen bacterium, Alcaligenes hydrogenophilus, was grown aerobically under heterotrophic conditions. Cells were resuspended with nitrogen-free mineral salt medium and incubated under a gas mixture of H₂, O₂, and CO₂.Membrane-bound and soluble hydrogenases could be induced in the non-proliferating cells after certain lag periods.Compounds supporting rapid growth strongly repressed the hydrogenases induction in the non-proliferating cells. It was also clarified by the method that carbon dioxide affected only the induction of soluble hydrogenase. Thus, this method enables us to analyze the effect of the component, which is indispensable for growth, on the induction.

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The contribution of ionized and unionized species to the overall permeation of weak electrolytes through the skin was investigated to determine the effect of pH in the vehicle on the permeability of indomethacin (IDM), as a model drug, through hairless rat skin. The permeability of IDM through polydimethylsiloxane(silicone) and poly(2-hydroxyethyl methacrylate)(pHEMA) membranes which may reflect lipid and aqueous pathway, respectively, was also measured for comparison. As the pH in the vehicle increased, there was an exponential increase in the skin permeation rate of IDM.The permeation rate of IDM through the silicone membrane was constant independent of pH, whereas that through the pHEMA membrane increased with increasing pH, similar to the skin permeation. The permeability coefficients of ionized and unionized species through the skin estimated using the skin permeation rates and solubilities of IDM at various pHs were 1.50×10^-7 and 2.79×10^-5 cm/s, respectively. These results indicated that the permeation of ionized species greatly contributed to the total permeation of IDM at higher pH, and that the total permeation rate of IDM was determined by the permeation of unionized species at lower pH. These contributions depend on the pH and pK_a values and the ratio of permeability coefficient of each species. It was also confirmed that the skin has at least two kinds of permeation pathways and these two species permeate through a different pathway.

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An orally applicable pulsatile drug delivery system in dry-coated tablet form was prepared using diltiazem hydrochloride as the model drug, and a polyvinyl chloride-hydrogenated castor oil-polyethyleneglycol mixture as the outer shell of the tablet. In vitro drug release from the prepared tablet exhibited a typical pulsatile pattern with a 7 h lag phase (non-drug release period). This dosage form was orally administered to three beagle dogs under non-fasting and fasting conditions, and the plasma concentration level of diltiazem was determined according to time after administration. The result of the in vivo study in non-fasting dogs suggested that the drug could be released in the gastrointestinal tract as in the in vivo test. However, under the fasting condition, a large difference in the plasma concentration profile was found, suggesting that the disintegration time of the tablet tended to be influenced by the feeding condition of subject.

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The effect of l-menthol on the skin permeability of mannitol, cortisone or indomethacin was examined by an in vitro penetration technique with hairless mouse skin. The donor solution was prepared with phosphate buffered saline, ethanol : buffered saline (20 : 80, v/v) or ethanol : buffered saline (20 : 80, v/v) containing 1% (w/v) l-menthol. Although ethanol showed little enhancing effect, l-menthol in an aqueous ethanol vehicle at pH 7.4 increased the permeability coefficients of mannitol and indomethacin by about 100 times that of the control (an aqueous vehicle) and increased that of cortisone by about 10 times. l-Menthol, however, scarcely enhanced the penetration of indomethacin at pH 3.0, the majority of the species being in unionized form. These results suggested that the menthol-ethanol-aqueous system enhanced skin permeability through a direct effect on the polar and/or lipid pathways, while the thermodynamic activity of the penetrant molecule in the delivery vehicle might also influence the effectiveness of the penetration enhancer.

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The absorption of insulin (from porcine pancreas) in rabbits after the nasal administration of aqueous preparations containing insulin and five kinds of cyclodextrins (CyDs) in phosphate buffer solution at pH 7.0 was investigated.Without CyD, the insulin and glucose levels in plasma were unchanged, whereas a marked increase in the plasma levels of insulin and a decrease in glucose concentrations were observed following the simultaneous administration of insulin and CyD such as α- and heptakis (2, 6-di-O-methyl)-β-CyD (DM-β-CyD). The largest enhancing effect on the nasal absorption of insulin was obtained by DM-β-CyD. To evaluate the duration of the absorption-enhancing effect of CyDs, preadministration (administration of CyD 0.5, 6, 12 and 24 h before insulin administration) was performed. The area under plasma concentration-time curve (AUC) and C_max of insulin significantly decreased with the preadministration of DM-β-CyD 6, 12 and 24 h before nasal administration. The absorption-enhancing effect disappeared 24 h after the preadministration. These findings demonstrate that CyDs enhance the nasal absorption of insulin, and the recovery of the membrane transport barrier function in nasal mucosa is achieved, at the latest, 24 h after the administration of CyDs.

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Adsorption of imipramine onto activated charcoal and a cation exchange resin, sodium polystyrene sulfonate were evaluated in macrogol (polyethylene glycol) electrolyte solution (PEG-ELS) and JP XII second medium. The maximum adsorptive capacity of activated charcoal for imipramine was 610 mg and 372 mg per g of charcoal in PEG-ELS and JP XII second medium, respectively. On the other hand, the maximum adsorptive capacity of sodium polystyrene sulfonate for the drug was 272 mg and 667 mg per g of the resin in PEG-ELS and JP XII second medium, respectively.Adsorption of imipramine onto both adsorbents was greater when macrogol was omitted from PEG-ELS than in PEG-ELS itself. Adsorption of the drug onto activated charcoal was decreased when sodium sulfonate or sodium bicarbonate was omitted from PEG-ELS, whereas that onto sodium polystyrene sulfonate was decreased only when sodium bicarbonate was omitted from PEG-ELS.

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The amounts of d-limonene, ethanol and indomethacin (IMC) which were transferred from aqueous gel ointments to the skin were determined in rats. The concentration of IMC in the skin correlated well with the plasma concentration of IMC percutaneously absorbed from the gel ointment. The increase of d-limonene concentration in the gel ointments was directly proportional to the accumulation of ethanol in the skin. The amount of ethanol in the skin was closely associated with the percutaneous absorption of IMC. As a possible mechanism for enhancement action of d-limonene and ethanol, it was considerd that, at first, d-limonene penetrates into the skin under coexistence with ethanol and may change the barrier structure of the stratum corneum. The transfer of ethanol to the skin is thereby enhanced under the coexistence of d-limonene in the skin. Thus, the permeation of IMC can be promoted due to its affinity with ethanol.

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A prevention method of the sorption of bromhexine HCl to plastic materials used in packaging was investigated.Four kinds of plastic packaging materials were used : Polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP) and polyacrylonitrile (PAN). Three polyethylenes having different densities were used. No effect of PE density on the sorption of bromhexine HCl from granules was observed. The effects of different kinds of plastics on the sorption of bromhexine HCl from solution and granules were studied. The sorption of bromhexine HCl to PAN, which had a high relative dielectric constant, was the most depressed among the four plastics. The sorption of meclizine HCl to PAN from the solution was also lowest, the same as bromhexine HCl.

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The effects of phenylalaninol (D-isomer) on gastric acid secretion and gastric ulcer were studied in rats. The compound reduced the gastric acid secretion stimulated by intracisternal thyrotropin releasing hormone and intravenous 2-deoxy-D-glucose, but not that stimulated by subcutaneous carbachol or histamine. Phenylalaninol prevented stress- and indomethacin-induced gastric ulcers. We conclude that phenylalaninol inhibits ulcer formation mainly by central inhibition of gastric acid secretion.

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Chiral synthesis of an erythrinan alkaloid, (-)-3-demethoxyerythratidinone (11), as well as a versatile intermediate, the 1, 7-cycloerythrinan derivative (14) (both are of enantio-type) was achieved using asymmetric acylation and kinetic resolution starting from the L-dopa derivative (1).

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Treatment of racemic α-methoxycycloalkanone oxime acetates 1 with (2R, 4R)-2, 4-bistrimethyl-silyloxypentane in the presence of a catalytic amount of trimethylsilyl triflate (TMSOTf) afforded the chiral acetal intermediates 3, which were reacted with silicon-containing nucleophiles to give the chiral ω-cyano compounds 4, in a one-pot operation.

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