Procedures for the estimation of the novel quantitative structure-activity relationships (QSAR) descriptors σ_s°, representing the contributions from both dispersion and repulsion interactions, have been presented for the substituted methane series. After correcting part of the symmerty, the rotation isomeer or racemate, observed values σ_s°(obs) for CH₂R_AR_B, CHR_AR_BR_C, and CR_AR_BR_CR_D can be given by the general equation σ_s°(obs)=aΣσ_s°(mono)+b, where σ_s°(mono) means the descriptor of the MeR series. The values estimated by this equation agreed with those of the observed ones, and several examples of the large molecule are submitted for the determination of the optimum value.Furthermore, the hydrophobic substituent constants π of typical α-amino acids are revealed to be expressed by the linear combination of the descriptor σ_s° based on the gas phase and indicator variable, implying the averaged number of hydration.

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Cyclic octapeptides (1-4) having analogous amino acid sequences were synthesized from the corresponding linear peptides using a conventional sulution-phase method. The cyclization was performed by the EDCI/HOBt procedure using an equimolar mixture of alkaline metal cations at a high dilution (concentration of linear peptide : 1.2 mM). The selective transport of amino acid methyl ester and amine salts through an organic liquid membrane mediated by the synthetic cyclic octapeptides and the enantiomer recognition properties in the transport of racemic Phe-OMe salt were examined. The cyclic octapeptides transported D-Phe-OMe salt more efficiently than other guest salts.

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6-Amino-6-deoxyfumagillol (5) was synthesized by reductive amination of 6-oxo-6-deoxyfumagillol (4), which was obtained by oxidation of fumagiollol (2). The reduction proceeded stereoselectively by the equatorial attack of hydride and 5 was found to have the same stereochemistry as that of 2. Several derivatives of 5 were prepared and most of them showed anti-angiogenic activity comparable to that of fumagillol derivatives.

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An agarose gel upon which a water-soluble cyclophane having three quaternary nitrogens was immobilized, Gel-QCP (3), was synthesized and its properties as a chromatographic stationary phase were studied. The affinity of Gel-QCP for several neutral and anionic aromatic guests was broadly consistent with that of the parent cyclophane (2). This suggests that the guest separation is attributable to the formation of inclusion complexes between the cyclophane moiety of Gel-QCP and the guests. Non-specific electrostatic interaction also influences anionic guests, but this effect is reduced by using an aqueous solution of NaCl as an eluent.

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Upon irradiation, N-but-3-enyl thiophthalimides 7 undergo intramolecular Paterno-Buchi-like cycloaddition to give thioimide-thietanes, which are also photocheically converted into pyridoisoindolones 9.

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Indenestrol A (IA) is a metabolite of diethylstilbestrol (DES), and indenestrol B (IB) is an analog of IA. IA was simply obtained from E, E-dienestrol in the presence of dilute sulfuric acid, and a mixture of IA and IB was formed by thermal cyclization of E, E-dienestrol. In order to elucidate the effects of optically active IA and IB on microtubule assembly, the IA and IB enantiomers were separated to >99% purity by high-pressure liquid chromatography using a chiral column. The di(4-bromobenzoate) of (-)-IB was analyzed by X-ray crystallography and its absolute structure was determined as C(3)-S. The (+)-, (-)-, and (±)-indenestrols A and B were shown to be inhibitors of microtubule assembly in vitro using microtubule proteins from porcine brain. (±)-IB is more active than (±)-IA, and the order of inhibitory activity of the enantiomers on microtubule assembly was (+)-IB>(+)-IA>(-)-IA>(-)-IB.

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In the course of our study on the ene reaction of trifluoromethyl ketones, a trifluoromethyl group has been observed to behave as a larger substituent than commonly believed in the biomedicinal field. To estimate the steric effect of a trifluoromethyl group, we synthesized several trifluoromethyl ketones (RCOCF)₃ and examined in detail their ene reaction with cyclohexene, a 1, 2-disubstituted ene having the least steric requirement. In this reaction, a trifluoromethyl group was found to behave as if it were a much larger substituent than a phynyl or isobutyl group and as large as a sec-butyl group.

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Three furanoterpenes, one having a furanocyclohexane ring (1) and two methyl ethers (2 and 3), and 12, 13-didehydrofurospongin-1 (4a) were isolated from the lipid extract of the sponge, Fasciospongia cavernosa SCHMIDT. The absolute configuration of 4a at C-11 was shown to be (S), opposite to that reported for furospongin-1 (5). Compound 4a was found to be quite labile in acidic media and was converted, at room temperature, to 1 (HClO₄ in dioxane) or to a mixture of 1, 2 and 3 (HClO₄ in MeOH). These results suggest that 1, 2 and 3 are at least partly artefacts formed from 4a during the isolation process.

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The furopyridone 10 was shown to be a potential synthon for eburnamine-vincamine alkaloids, including cuanzine, by facile conversion to kye intermediates 15, 18, and 22 for the synthesis of natural alkaloids.

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Bicyclic β-lactams, such as 1-oxa- and 1-carba-penams, are reductively cleaved between the lactam carbonyl group and the α-carbon by palladium catalysts to give formamide derivatives.

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A detailed account is given of the first chemical synthesis of hypoxanthine 7-N-oxide (5), which started from coupling of 6-chloro-5-nitro-4(3H)-pyrimidinone (7) with N-(4-methoxybenzyl)phenacylamine, generated in situ from the hydrochloride (8), and proceeded through cyclization of the resulting phenacylaminopyrimidinone (9) and removal of the 4-methoxybenzyl group. The results of catalytic hydrogenolysis, methylation followed by catalytic hydrogenolysis, and rearrangement under acidic conditions of 5 supported the correctness of the assigned structure. An ultraviolet spectroscopic approach suggested that the neutral species of 5 exists in H₂O mainly as the N(7)-OH tautomer (21). In the in vitro bioassay of antileukemic activity against murine L5178Y cells, 5 was weakly cytotoxic, with IC₅₀ of 100μg/ml. It did not show any antimicrobial activity even at 1000μg/ml. None of the 9-(4-methoxybenxyl) (11) and O-methyl (12, 13, and 14) derivatives was found to be antiieukemic or antimicrobial.

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As a model study on the synthesis of natural products possessing an eight-membered cyclic ether or amine framework such as laurencin (1) and FR900482 (6), two kinds of 2-benzyl oxacyclooctanones (7 and 8) and 2-methyl azacyclooctanones (9 and 10) were synthesized from the corresponding twelve-membered lactam sulfoxides (49-52) by applying our general method for medium-ring ketone synthesis. The corresponding lactam sulfides were readily prepared from the linear ω-tosyl carboxylic acids containing on oxygen atom (11 and 12) or methylcarbamate group (13 and 14) by condensation with 2-cyanoethyl 2-N-methylaminophenyl sulfide followed by alkylation.

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A series of 3, 4-dihydro-3-oxo-1, 4-benzoxazine-8-carboxamide derivatives was synthesized and evaluated for serotonin-3 (5-HT₃) receptor antagonistic activity assessed by their ability to antagonize the von Bezold-Jarish (BJ) effect in rats. Derivatives bearing 1-azabicyclo[2.2.2]oct-3-yl moiety as a basic function attached to the carboxamide at position 8 showed more potent antagonistic activity than those bearing the other three basic moieties. Structure-activity relationships of this series showed that methyl and chloro groups were more effective as substituents at positions 4 and 6, respectively. The representative compound 15 (Y-25130) in this series showed potent antagonistic activity on the BJ effect (ED₅₀=1.3μg/kg i.v.), high affinity for 5-HT₃ receptor (K_i=2.9nM) and complete protection against cisplatin-induced emesis in dogs at a dose of 0.1mg/kg i.v.

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3-Isobutyryl-2-isopropylpyrazolo[1, 5-α]pyridine (ibudilast) has a large number of metabolites. In order to unequivocally establish the true identity of these metabolites, we prepared a series of authentic reference compounds, namely novel pyrazolo[1, 5-α]pyridine derivatives with mono- and dihydroxylated alkyl side chains and carboxylated alkyl side chains. These results lead to the conclusion that reactions at the 3-position of pyrazolo[1, 5-α]pyridine are governed by the electron-donating effect and the weak basicity of bridge-head nitrogen. On the basis of these results we were able to establish a method of functional group introduction to the alkyl side chains of pyrazolo[1, 5-α]pyridine.

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Novel 6-hydroxylated or methanesulfonylated pyrazolo[1, 5-α]pyridine derivatives as an authentic reference of metabolites for 3-isobutyryl-2-isopropylpyrazolo[1, 5-α]pyridine (ibudilast) were prepared by the method of substitution with Br⁺ on the pyridine ring and subsequent displacement of Br with MeO^- or MeS^-. For this reason, we investigated the orientation of halogenation on the pyridine ring of pyrazolo[1, 5-α]pyridine. The reactivity of the pyridine ring was at the 6-position, folowed by the 4-position. We supposed that this finding comes from the electron-donating resonance effect of bridge-head nitrogen. These experimental results were in good agreement with the results of atomic electron densities, but a clear difference was not obtained in those of the Frontier orbitals.

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6, 7-Dihydrodiol (1) has been isolated as a principal metabolite of ibudilast. We determined the structural formula of this compound (1) and made the stereochemical behavior is solution clear by the results of nuclear magnetic resonance (NMR) spectra. From these results, 6, 7-dihydrodiol (1) exists as the equilibrium mixture of diastereomers and this equilibrium is influenced by the polarity of the solvent. It is concluded that 6, 7-dihydrodiol (1) exists mainly as a cis quasi-equatorial-quasi-axial conformation (7-OH quasi-axial) in a non- or weak-polar solvent and mainly exists as a trans quasi-diaxial conformation in a polar solvent.

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1α, 25-Dihydroxy-21-norvitamin D₃ (3) was synthesized from 1α-hydroxydehydroepiandrosterone (4). Certain biological properties of 3 were examined in comparison with those of 1α, 25-dihydroxyvitamin D₃ (1) and 1α, 25-dihydroxy-21-nor-20-oxavitamin D₃ (2) to evaluate the effect of the 21-methyl substituent on biological activities. The differentiation-inducing activity of 3 towards human myeloid leukemia cells was approximately one-fifth of that of 1, while in the binding affinity with chick intestinal cytosolic receptor, 3 was about one-tenth of that of 1. The rather weak effect of 3 on serum calcium levels in normal mice at a dosage of 500μg/kg (intravenous administration) indicates that the essential importance of the 21-methyl moiety may lie in its effect on the regulation of calcium metabolism.

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A series of 4-amino-5-chloro-2-methoxy- and 2-ethoxy-N-[(4-substituted 2-morpholinyl)methyl]benzamides (11-64) were prepared and evaluated for gastrokinetic activity by determining their effects on the gastric emptying of phenol red semisolid meal in rats. The N-4 substituent includes alkyl, phenoxyalkyl, (4-fluorobenzoyl)alkyl, and heteroarylmethyl groups. The benzamide derivatives, having an isopropyl, isoamyl, neopentyl, 3-(4-chlorophenoxy)-propyl, or pyridylmethyl group at N-4, showed potent in vivo gastric emptying activity. In particular, 4-amino-5-chloro-2-ethoxy-N-[[4-(3-pyridylmethyl)-2-morpholinyl]methyl]benzamide (57b) was equipotent to the 4-fluorobenzyl analogue 1b (AS-4370 as its citrate) in the gastrokinetic activity on phenol red semisolid meal in rats and mice, and on resin pellet solid meal in rats. Moreover, compound 57b was free from dopamine D₂ receptor antagonistic activity in both in vitro ([³H]spiperone binding) and in vivo (apomorphine-induced emesis in dogs) tests. Structure-activity relationships of compounds with various substituents at N-4 are also discussed.

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Amides, 2 and 3, related to the potent antifungal triazole-amide 3-acylamino-2-aryl-1-triazolyl-2-butanol (1) were synthesized starting from the triazole-alcohol 6. The antifungal activity of 2 and 3 aganist a mouse systemic Candida albicans infection was found to be less potent than that of 1.

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The metabolite of loprinone (E-1020) in dogs, 5-(2-aminopyridin-5-yl)-1, 2-dihydro-6-methyl-2-oxo-3-pyridine-carbonitrile (9), was prepared via ozonolysis of imidazo[1, 2-α]pyridinylpyridines and evaluated for positive inotropic activity. Its potency was less than that of loprinone and milrinone. Among compounds related to loprinone which were synthesized using the versatile intermediates (10a, b) obtained during the preparation of 9, only 5-(2-aminoimidazo[1, 2-α]pyridin-6-yl)-1, 2-dihydro-6-methyl-2-oxo-3-pyridinecarbonitrile (27) retained the activity of loprinone. The electron-withdrawing substituents at hte 2-position of imidazo[1, 2-α]pyridine reduced the activity of the parent compound.The ozonolysis of imidazo[1, 2-α]pyridine derivatives under neutral confitions afforded 2-acylaminopyridine derivatives in a 30-55% yield independent of the substituents at the 2-position of imidazo[1, 2-α]pyridine. It is possible to use imidazo[1, 2-α]pyridine as protected 2-aminopyridines, and 2, 3-unsubstituted imidazo[1, 2-α]pyridines are convenient for that purpose from the viewpoint of ease of preparation of the starting material.

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A series of 2-[(2-imidazolylsulfinyl)methyl]anilines (2) having various substituents on their imidazole and aniline rings was synthesized and examined for their H⁺/K⁺-ATPase (adenosine triphosphatase) inhibitory effects and antisecretory activity against histamine-stimulated gastric acid secretions in Heidenhain pouch dogs. Although substituations on the imidazole ring did not enhance biological activity, substitution on the aniline ring be electron-donating substituents potently enhanced the enzyme inhibitory activity and also showed an inhibitory effect on histamine-stimulated gastric acid secretion after oral administration. In particular, the in vitro activity of the dimethyl (2u-w) and trimethyl (2ac) derivatives was about 10 times that of omeprazole. Also, 4-methyl (2k), 4-methoxy-5-methyl (2y) and 3, 5-dimethyl-4-methoxy (2ab) derivatives showed a potent antisecretory effect of more than 80% after oral administration at 6mg/kg. Although these aniline derivatives have relatively low stabilities in aqueous solution, replacement of the isobutyl group at the aniline nitrogen atom with N-(2-methoxyethyl) group enhanced the stability.

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Several E-ring-modified analogues of (RS)-camptothecin were synthesized by total synthesis via Friedlander condensation and evaluated for cytotoxicity and antitumor activity against P388 mouse leukemia cells. Among them, (RS)-20-deoxyamino-7-ethyl-10-methoxycamptothecin (25c) was found to be more active than (RS)-camptothecin (1) in the in vivo assay.

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Five new acylated glucosides of okanin, okanin 4-O-(6"-O-acetyl-2"-O-caffeoyl-β-D-glucopyranoside, okinin 4-O-(2"-O-caffeoyl-6"-O-p-coumaroyl-β-D-glucopyranoside), 4-O-methylokanin 4'-O-(6"-O-p-coumaroyl-β-D-glucopyranoside, 4-O-methylokanin 4'-O-(6"-O-acetyl-β-D-glucopyranoside), 4-O-methylokanin 4'-O-(6'-O-acetyl-2"-O-caffeoyl-β-D-glucopyranosid), have been isolated from the fresh leaves of Bidens frondosa. These structures have been elucidated on the basis of spectral data and chemical correlation.

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The stability constants of metal complexes for several pyridone carboxylic acid drugs (ofloxacin, norfloxacin and lomefloxacin) were determined by potentiometry and spectrophotometry. The values of aluminum complexes, magnesium complexes and calcium complexes were Ca<Mg&Lt;Al. The stability constants of lomefloxacin complexed with divalent transition metal ions were determined and these values followed the Irving-Williams series (Mn<Fe<Co<Ni<Cu>Zn). The stability constants of metal complexes for several pyridone carboxylic acids synthesized were also determined and compared with those for pyridone carboxylic adic drugs. The stability constants of these compounds gradually increased with an increasing pK_a value of the carboxyl group of pyridone carboxylic acid. In the case of aluminum complexes, the complexes Al(OH)L and Al(OH)₂L were formed under weak acidic conditions and the dissociation constants for the hydrolysis of the aluminum complexes were determined. The participation of the carboxyl group and the carbonyl group in the chelating reaction was confirmed by the measurement of carbon-13 nuclear magnetic resonance of the aluminum complex and the magnesium complex. These results suggest that when pyridone carboxylic acids are administered with metallic antacid containing aluminum hydroxide and magnesium oxide, aluminum complexes AIL, Al(OH)L or Al(OH)₂L are formed and the adsorption of the drugs in the intestines is reduced.

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Human serum albumin (HSA) labeled with ^99mTc (^99mTc-HSA) was analyzed by high performance liquid chromatography using a 4-vinylpyridinium polymer column which specifically resolved albumin components such as human mercaptalbumin (HMA), human non-mercaptalbumins (HNA), etc. The ^99mTc-HSA radiochromatogram revealed that ^99mTc-HSA consisted of several components. The radiochromatographic profile was similar to that of ^99mTc-HMA prepared with ^99mTc and separated HMA. This suggested that HMA participated mainyl in ^99mTc-labeling of HSA. When HSA was labeled with a stoichiometric concentration of ^99mTc, the HMA peak was significantly decreased and new peaks were revealed by absorbance at 280 nm. From these results, the role of HMA in labeling HSA with ^99mTc was elucidated.

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Anti-tauro 1β-hydroxycholic acid antisera were prepared by immunizing rabiits with N-(1β-3α-7α-12α-tetrahydroxy-5β-cholan-24-oyl)glycine bovine serum albumin conjugate. The immunoglobulin G fraction was obtained by ammonium sulfate precipitation, followed by diethylaminoethyl cellulose column chromatography. The antibody was characterized using [2_^3H]tauro 1β-hydroxycholic acid which has a high affinity (K_a=1.09×10⁹M^-1) and reasonable specificity. Cross-reactivity for glyco 1β-hydroxycholic acid was 100% and those for other 1β-hydroxylated bile acids ranged from 4.32 to 29.6%. Concentrations of conjugated 1β-hydroxycholic acid in urine of newborns at 0-20d after birth were determined by radioimmunoassay to be significant (0.2-11.1 μg/ml), exhibiting a tendency to increase during the 20d after birth.

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As an advanced stage of glycation, glycated human serum albumin (G-HSA; glucose content, 2mol of 5-hydroxymethylfufural equivalent/mol of HSA) was incubated at 37°C up to 30d in 0.2M phosphate buffer, pH 7.4, with 100 μM Fe³⁺. G-HSA incubated for 30d (G-HSA-30(Fe)) was subsequently hydrolyzed at 110°C for 24h in 6N HCl. In the hydrolysate, N²-carboxymethyllysine (CML) was identified by cochromatography with synthesized CML on an amino acid analyzer. pI of HSA (4.8) shifted to 4.5 in G-HSA. A more acidic fraction, pI 4.3, appeared in G-HSA-30(Fe). CML content (mol of CML/mol of HSA) of HSA and G-HSA was as follows; 0 in HSA, 0.2 in HSA-30(Fe), 0.4 in G-HSA and 1.5 in G-HSA-30(Fe) pI 4.3. The amino acid compositions also changed in lysine, arginine and tyrosine at the advanced stage of the reaction.

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Semiquinone radicals of menadione were generated during the reaction of menadione with reduced glutathione (GSH), dependent upon the pH. Under aerobic conditions, cytochrome c was reduced during the reaction, and superoxide dismutase (SOD) inhibited the cytochrome c reduction. The inhibitory effect of SOD was greater at a high pH than at a low pH. In the presence of Fe³⁺ or ethylenediaminetetraacetic acid (EDTA)-Fe³⁺, deoxyribose was degraded during the reaction of menadione with GSH, dependent upon the pH. Greater amounts of deoxyribose were degraded at a low pH than at a high pH. The reduction of Fe³⁺ of EDTA-Fe³⁺ also depended on the pH, and SOD strongly inhibited the Fe³⁺ reduction, indicating that Fe³⁺ or Fe³⁺-EDTA was reduced by superoxide. SOD, catalase, mennitol and benzoate inhibited the deoxyribose degradation at various pH values. These results indicate that the menadione semiquinone radical is readily formed at an alkali pH but a hydroxyl radical is predominantly produced near a neutral pH. A hydroxyl radical may be generated via an iron-catalyzed Haber-Weiss reaction.

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The relationship between cell growth and the secretion of poly(3-hydroxybutyrate) (PHB) depolymerase by Alcaligenes faecalis T1, a gram-negative bacterium, was studied with various carbohydrates added to the medium as sole carbon sources. A. faecalis T1 could grow on many kinds of carbon sources, the growth rate depending on the carbon source species. However, among the various carbon sources tested, glucose, PHB and its metabolites, D(-)-3-hydroxybutyrate and acetoacetate, but not succinate or other carboxylic acids, caused the secretion of PHB depolymerase. In the medium containing glucose as a sole carbon source, A. faecalis T1 started to grow and to secrete PHB depolymerase after 60h of cultivation. In contrast, the growth of cells in the medium containing succinate as a sole carbon source staeted within 2h and reached a plateau level after 6h of cultivation, but the cells did not secrete the enzyme into the culture medium. However, succinate-grown cells contained a considerable amount of PHB depolymerase, the level being the same as that in glucose-grown cells. Most of the cellular PHB depolymerase was found to be localized in the membrane fractions prepared from the glucose- and succinate-grown cells. In contrast to the glucose-grown cells, the succinate-grown cells exhibited no ability to incorporate [¹⁴C]glucose, although the cells exhibited several glycolytic enzyme activities for glucose oxidation. Therefore, it seems that the glucose availability for this bacterium is dependent on the induction of some protein(s) essential for glucose uptake and that glucose metabolites such as ketone bodies are essential for PHB depolymerase secretion by A. faecalis T1.

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Inhibitory effects of pure pentagalloylglucose (1, 2, 3, 4, 6-penta-O-galloyl-β-D-glucose) on purified nicotinamide adenine dinucleotide (NADH) dehydrogenase of the respiratory chain of Photobacterium phosphoreum were investigated. Pentagalloylglucose inhibited the NADH-ubiquinone-1, NADH-menadione, and NADH-2, 6-dichlorophenolindophenol oxidoreductase activities with less than 150nM of a 50% inhibition concentration (IC₅₀), but hardly inhibited NADH-ferricyanide and NADH-cytochrome c oxidoreductase activities with at least less than 0.5μM of pentagalloylglucose.Pentagalloylglucose inhibited noncompetitively the NADH dehydrogenase pf P. phosphoreum, which belongs to NADH dehydrogenase II (NADH dh II), and its inhibitor constant (K_i) to NADH-ubiquinone-1 oxidoreductase activity was estimated as 30nM of pentagalloylglucose. Therefore, pentagalloylglucose is the potent inhibitor of NADH dh II, more than flavone (IC₅₀=150μM for NADH-ubiquinone-1 oxidoreductase activity) which has previously been reported as an inhibitor for NADH dh II.

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The antioxidant activities of pueraria glycoside (PG)-1 (isoflavonoid) and mangiferin (xanthonoid) were studied and compared with PG-3 and daidzein (isoflavonoids) and with wogonin (flavonoid). PG-1 and mangiferin rapidly scavenged 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical, and inhibited lipid peroxidation which was initiated enzymatically by reduced nicotinamide adenine dinucleotide phosphate (NADPH) or non-enzymatically be ascorbic acid or Fenton's reagent (H₂O₂+Fe²⁺) in rat liver microsomes. Wogonin inhibited the enzymatically induced lipid peroxidation but had no scavenging effect on DPPH radical or on the non-enzymatic peroxidation. PG-3 and daidzein did not show any of these effects. Formation of Fe²⁺ by NADPH-dependent cytochrome P-450 reductase was inhibited by wogonin, but not by PG-1 or mangiferin. PG-1 and mangiferin had no effect on terminating radical chain reaction during the lipid peroxidation in the enzymatic system of microsomes or in the linoleic acid hydroperoxide-induced peroxidation system.These results suggest that PG-1 and mangiferin have an antioxidant activity, probably due to their ability to scavenge free radicals involved in initiation of lipid peroxidation. In contrast, wogonin may affect NADPH-dependent cytochrome P-450 reductase action, since it inhibited only the enzymatically induced lipid peroxidation.

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Clarithromycin (6-O-methylerthromycin), a new 14-membered macrolide antibiotic, has been studied to clarify its physicochemical properties and stability in acidic solution, as compared with erythromycin (EM).The solubility of clarifhromycin (CMC) in distilled water was lower than that of EM and decreased with increasing temperature. The solubilities of CAM and EM in the phosphate buffer solution at 37°C decreased with an increasing pH and kept constant above pH 9. From pH-solubility profiles, the dissociation constants of CAM and EM were determined to be 8.76 and 8.36, respectively. The partition coefficient of CAM took a higher value than that of EM and increased with an increasing pH.In the acidic splution, the decomposition of CAM and EM obeyed the pseudo-first order kinetics. From the decomposition rate constants, the half life (T_1/2) of CAM and EM were determined. In pH 1.39, CAM degraded with a T_1/2 of 17 min while EM kinetics corresponded to a T_1/2 of 3s. Therefore, CAM was 340-fold more stable in pH 1.39 and markedly more stable in the acidic solution than EM.

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Concerning the new microencapsulation method based on surface neutralization of enteric polymers, the effect of polymer species on microcapsule (MC) properties was studied. First, the encapsulation of crystal aspirin was performed at 40°C using nine kinds of enteric polymer. It was known that cellulose derivative polymers such as hydroxypropyl methylcellulose acetate succinate (HPMCAS-L, -H), cellulose acetate phthalate (CAP), hydroxypropyl methylcellulose phthalate (HP-55) and carboxymethylethylcellulose (CMEC) produce effective membrane, while synthetic acrylate polymers such as methacrylic acid-methacrylic acid methylester (Eudragit L, S) and methylacrylate-methacrylic acid copolymer (MPM-05) do not.Then, microencapsulation was performed changing the preparation temperature from 10 to 60°C for HPMCAS-H, -L, CAP, CMEC and Eudragit S. The polymer content in MCs generally increased by raising the temperature with the exception of HPMCAS-H. In HPMCAS-H, the polymer content was at a miximum around 40°C. The amount of consumed core aspirin generally increased with the increase of the preparation temperature. As a rule, the amount was the least in polymers which need the least alkali for their dissolution into water. The dissolution depresison of aspirin into the JP XI 1st fluid showed various tendencies due to the polymer species. Eudragit S hardly depressed at any preparation temperature. CMEC and HPMCAS-H depressed maximally around 30-50°C. CAP depressed the most with the increase of the temperature.In order to elucidate these phenomena, phase separation behaviors were observed for the five polymers at various pHs and temperatures. As a resulets, the state of the polymer phase around pH 2.0-2.5 concerned well with the properties of the MCs.

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A nicotine agonist, ¹¹C-labeled (S)-nicotine, was synthesized by N-methylation of (S)-nornicotine with [¹¹C]-methyl iodide in dimethylformamide-dimethylsulfoxide in order to study nicotinic receptors in the human brain by positron emission tomography. The radiochemical yield of this N-methylation reaction was more than 90% within 5 min. After purification by high performance liquid chromatography the radiochemical purity of the product was more than 99% and the specific radioactivity was 7.4-11.1 GBq/μmol. The regional distribution of (S)-[¹¹C]nicotine in the mouse brain after intravenous injection was compared with that of (R)-[¹¹C]nicotine. After injection of (S)-[¹¹C]nicotine, the regional uptake of radioactivity was in the following order : cortex > thalamu&ap;hippocampus>striatum>hypothalamus>cerebellum. Moreover, (S)-[¹¹C]nicotine was displaced from the brain by unlaceled (S)-nicotine, but unlabeled (R)-nicotine caused no change in uptake. In contrast, (R)-[¹¹C]nicotine showed a lower brain uptake and lesser regional differences in radioactivity.

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[³H]Water and [¹⁴C]inulin were injected into perfused rabbit muscle with or without hyaluronidase (300 units/ml) and their absorption into venous effluent from muscle was determined. Hyaluronidase accelerated the absorption of both compounds but the enhancement of [¹⁴C]inulin was much larger than that for [³H]water. The pharmacokinetic analysis of venous appearance curves based on a physiological diffusion model elucidated that interstitial diffusion of [¹⁴C]inulin was remarkably increased by hyaluronidase treatment, suggesting the existence of steric hindrance for it by the polysaccharide network nuder normal conditions. Enhancement of [³H]water diffusion was also detected although enhancement ratio was about one-half of that of [¹⁴C]inulin. Mean time necessary for each process was calculated using the statistical moment concepts. The results suggested predominant contribution of the interstitial diffusion process and secondary and little contribution of local perfusion flow and permeation process across the capillary wall, respectively, in total absorption of [¹⁴C]inulin. Effect of hyaluronidase on transcapillary movement of [¹⁴C]inulin was studied using an in vitro diffusion experiment with cultured endothelial cell monolayer and no enhancing effect was shown on [¹⁴C]inulin transport across the cell monolayer. The contribution of the local perfusion flow, on the other hand, was shown to be almost equivalent to that of the diffusion process in the total absorption of [³H]water.

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Formulation optimization of sustained-release tablet of chlorpheniramine maleate (CPM) was performed by means of an extreme vertives design and simultaneous optimization technique. Polyvinylpyrrolidone, carboxyvinyl polymer and crystalline cellulose were used as excipients of the tablet. Mixing ratios of these polymers were selected as formulation factors. In addition, the tablet diameter was employed as an independent process variable. Release parameters of CPM in the model formulations were estimated by using an exponential model for the drug diffusion. These parameters were selected as response variables and optimized by the simultaneous optimization technique. Response variables predicted with the optimum formulations agreed well with the experimental results, suggesting usefulness and reliability of the computer optimization method based on the extreme vertices design and simultaneous optimization technique.

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To improve undesirable pharmaceutical properties of prostaglandin E₁ (PGE₁) in lyophilized formulation, potential use of highly water-soluble maltosyl-β-cyclodextrin (G₂-β-CyD) was examined, comparing it with parent β-cyclodextrin (β-CyD). Inclusion complexation of PGE₁ with G₂-β-CyD in an aqueous solution was estimated by the solubility method, circular dichroism and carbon-13 nuclear magnetic resonance spectroscopies. PGE₁ was freeze-dried with various additives and subjected to stability and dissolution testd. When the amorphous products were stored at 60°C, decomposition of PGE₁ was significantly decelerated by both G₂-β-CyD and β-CyD, while it was accelerated by mannitol as an inert ingredient. During storage, the rapid dissolving property of PGE₁ was maintained by complexation with G₂-β-CyD, while it tended to decrease by β-CyD, depending on the moisture-adsorbing and wetting properties along with crystallinity change of the additives. The limited data obtained here suggests that G₂-β-CyD may be preferable to β-CyD for the improvement of chemical instability and poor dissolution properties of PGE₁ in dry solids for injections.

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An experimental theorem (1) is proposed for conversion of the curve representing powder bed compression by tapping into a straight line. The theorem was found to apply to a variety of particulate solids : ε_e=-b log a+k (1)where ε_e is the porosity of the powder bed at a stable state for specific acceleration levels, a is the acceleration caused by tapping at constant height differences (Δh), and b and k are constnts.If the speed of pouring the powder bed with the sample was high, two continuous straight lines (lines 1 and 2) were obtained. Line 1 was thought to represent the porosity primarily due to the interaction between the particles and the walls of the container, in addition to the porosity at a table state for the mostly loosely filled sample. Line 2 was considered to represent the maximum porosity under a constant acceleration when there is no interaction between the container and sample.The two lines could be approximated by line 3 at low filling speeds. This straight line is believed to represent the porosity for the most dense packing under a constant acceleration. The three straight lines tend to converge into a single line as the particle size is reduced. A correlation was also found between the slope of line 3 and the particle size.

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The psychotropic effects of "Hokkai-Kisso", i.e. roots of Japanese valerian, were compared with those of diazepam and imipramine. Both 30% EtOH extract of valerian root (11.2g/kg) and diazepam (3mg/kg) significantly prolonged hexobarbital-induced sleep in mice. Spontaneous ambulatin and rearing during an open field test were significantly decreased by valerian extract (11.2g/kg), but kessyl glycol diacetate (KGD, 400mg/kg) and diazepam (3mg/kg) significantly increased ambulation. Diazepam (10mg/kg) significantly devreased approach-avoidance conflict in mice in a water-lick conflict test, but valerian extract and KGD did not.By contrast, valerian extract (4.1g/kg) and imipramine (20mg/kg) significantly inhibited immobility induced by a forced swimming test in rats, but did not increase spontaneous motor activity during an open field test just before the forced swimming test.In addition, valerian extract and imipramine significantly reversed reserpine-induced hypothermia in mice. These results indicate that valerian extract acts on the central nervous system and may be an antidepressant

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(+)-6-(2-Chlorophenyl)-3-cyclopropanecarbonyl-8, 11-dimethyl-2, 3, 4, 5-tetrahydro-8H-pyrido[4', 3' : 4, 5]thieno-[3, 2-f]triazolo[4, 3-a][1, 4]diazepine (E1623) is a very potent platelet-activating factor (PAF) receptor antagonist and shows potent anti-PAF activities at the microgram level in a variety of animal models. In order to examine the pharmacokinetics of E6123 at low doses, estabilishment of a radioimmunoassay is required. On the basis of the metabolic pattern of E6123, we synthesized 6-{2-chloro-4-(3-carboxypropyl)phenyl}-3-cyclopropanecarbonyl-8, 11-dimethyl-2, 3, 4, 5-tetrahydro-8H-pyrido[4', 3' : 4, 5]thieno[3, 2-f][1, 2, 4]triazolo[4, 3-a][1, 4]diazepine 22 as a potential hapten. In the synthesis of 22, we developed butynyl carbamate as a piperidine ring N-protecting group to prevent possible side reaction, namely oxidation of the methylene at position 2. This protecting group is stable under usual basic and acidic conditions.

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A new antileukemic alkaloid, agelasine G (1a), has been isolated from the Okinawan marine sponge Agelas sp. and its structure elucidated to be a bromopyrrole alkaloid containing 9-methyladenine and diterpene moieties on the basis of the spectroscopic data.

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2-(4-Substituted phenyl)oxazolidinium 3-methylides (5), prepared by fluoride ion-induced desilylation of 3-methyl-2-(4-substituted phenyl)-3-(trimethylsilyl)methyl-1, 3-oxazolinium iodides (4), rearranged to 4-methyl-2-(4-substituted phenyl)morpholines (8, Stevens rearrangement products) as the main products.

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On the basis of a hypothesis that cyclization and alkylation of the diamine part in formula 1 may give highly active compounds, a new series of 5-isoquinolinesulfonamide derivatives, shown as formula 2, were prepared from cyclic diamines. Their vasodilatory effects were subsequently evaluated in vivo according to the increase in arterial blood flow after the formulas were injected locally to the femoral and/or vertebral arteries of dogs. Cyclization of the diamine structure in formula 1 gave very potent vasodilators : 6 and 14. Acylation and sulfonylation of terminal amino nitrogen afforded much less potent ocmpounds. In contrast to the hypothesis, alkylation on the ring carbon and the terminal nitrogen of the cyclic amino afforded less active compounds except for compound 11. The most active compounds, 6, 11 and 14, showed more potent vasodilatory effects and more selective activity to the vertebral artery than either trapidil or diltiazem.

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3-Benzoylpropionic acid derivatives possess an immunomodulative activity and suppress adjuvant arthritis. To understand how substitutents affect the biological activity, the quantitative structure-activity relationships of 30 compounds were analyzed by the adaptive least-squares method. For the suppressing activity in rats, the electronic effects and the structural feature of the substituent on benzene ring were suggested to be important. To reinforce and confirm the correlation, 4 additional compounds of phenoxybutyric acid derivatives were synthesized and tested with the rat sdjuvant-induced arthritis. These compounds were found to have potent suppressing activity.

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Two new phenylethylchromone derivatives were isolated from a methanol soluble portion of pyridine extract of agalwood (Jinko). Their structures were elucidated as (5S, 6R, 7S, 8R, 7'R)-7'-hydroxyisoagarotetrol (1) and its (7'S)-isomer (2), respcetively.

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Two new triterpenoid glycosides, named mimengosides A (1) and B (2), along with acteoside (3) were isolated from the Buddlejae Flos (flower and bud of Buddleja officinalis). The structures of 1 and 2 were determined as 3-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→3)-[β-D-glucopyranosyl-(1→2)-β-D-fucopyranoside of 16-dehydroxysaikogenin G and that of 3, 23, 28-trihydroxy-11-methoxy-olean-12-ene, respectively, by spectral and chemical methods.

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A capillary-isotachophoresis system for the analyses of algal acidic polysaccharides was developed on the basis of some improvements on the conventional methods of analysis for glucosaminoglucans. Under the newly-developed conditions the zone responsible for the heparinoid active component (a rhamnan sulfate) in Monostroma nitidum was successfully separated from the zones of other acidic polysaccharides in crude polysaccharide fractions, since only one of the zones on the isotachopherogram of the crude polysaccharide fraction was detected on the isotachopherogram of the purified active rhamnan sulfate. In the analyses of the crude polysaccharide fractions from some related species, the corresponding zones with the same potential unit value as the purified active rhamnan sulfate from M. nitidum were observed only in species with considerably high activity. These results suggested that this new system, with simple, rapid and microscale procedures, is useful in examining the molecular homogenity of purified active sulfated polysaccharides, as well as in surverying the distribution of similar molecular species in related algal species.

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8-Hydroxypyrene-1, 3, 6-trisulfonic acid (HPTS, pyranine) is highly fluorescent not only in the alkaline range but also at an acidic pH, and in a water-soluble fluorescent compound. By phosphorylation of a pyranine, its fluorescence intensity was quenched markedly. A pyranina phosphate was shown to be a potential fluorogenic substrate for the assay of acid and alkaline phosphatases, and also for phosphatase activities in human serum.

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The powder coating of a bamboo, Lingnania chungii MCCLURE (=Bambusa chungii) was found to be a rich source of the 3-oxo pentacyclic triterpenes (25% on the recovery basis by chromatography on silica gel) which contained friedelin, arborinone and glutinone as the major components accompanied by minor amounts of α- and β-amyrenones. A simple procedure for isolation of friedelin is described. All proton and carbon-13 nuclear magnetic resonance signals for arborinone, friedelin and glutinone were assigned.

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We established a highly sensitive double-antibody enzyme immunoassay (EIA) for angiotensin (ANG) II. For competitive reactions, the ANG II-antibody was incubated with ANG II standard (or sample) and β-D-galactosidase-labeled AGN II (delayed addition). Free and antibody-bound labeled antigen were separated using an anti-rabbit immunoglobulin G (IgG) coated immunoplate. The enzyme activity on the plate was fluorometrically determined. The present immunoassay allows detection of 0.4 to 72fmol/well of ANG II. Using the present EIA, ANG II-like immunoreactivity (-LI) in human plasma was determined. The level of ANG II-LI in human plasma from 10 healthy volunteers was 33.3±10.4pmol/l.

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