Coupling of 6- and 2-halo-9-phenyl-9H-purines (1, 2, and 5) with terminal acetylenes in dimethylformamide (DMF) was well catalyzed by bis(triphenylphosphino)palladium chloride [PdCl₂(PPh₃)₂]to give the corresponding alkynyl-9-phenyl-9H-purines (3 and 4).Conversion of alkynyl-9-phenyl-9H-purines (3 and 4) into the corresponding purinylmethyl ketones (6 and 7) was achieved by treatment with an aqueous solution of mercuric sulfate and sulfuric acid (method A) or with piperidine and oxalic acid dihydrate (method B). On the other hand a trimethylsilylethynyl group on the 9H-purine ring was converted into an acetyl group by hydration using method A.Addition of sodium methoxide to 6-(trimethylsilylethynyl)-9-phenyl-9H-purine (3d) took place to give 6-(2, 2-dimethoxyethyl)-9-phenyl-9H-purine (10), while 2-(trimethylsilylethynyl)-9-phenyl-9H-purine (4c) reacted with sodium methoxide under the same conditions to give 2-(2-methoxyethenyl)-9-phenyl-9H-purine (11).

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A new dimeric epipolythiodioxopiperazine named chetracin A with two tetrasulfide bridges was isolated from Chaetomium nigricolor and C. retardatum, and the structure (3) proposed chiefly from proton and carbon-13 nuclear magnetic resonance (¹H-and ¹³C-NMR) data was established by X-ray analysis. Two congeners of chaetocin (2) named chaetocins B and C were isolated from C. virescens var. thielabioideum, and were proved tobe homologs with one disulfide and one trisulfide bridge (9) and with two trisulfide bridges (10), respectively, from spectral data, chiefly NMR and fast atom bombardment mass spectrometry/mass spectrometry (FAB MS/MS). The structure-activity relationships observed for the antibacterial activity and cytotoxicity of the related compounds are discussed.

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Benzylpenicilloic acid α-amides (1a-d) prepared by aminolysis of benzylpenicillin were treated with arylamines (2, 7, 9 and 13a-f) in the presence of acetic acid to give D-penicillamine (3) in good yield and high purity. The structures pf the by-products formed in these reactions were also determined.

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Condensation of diaminomethylenehydrazones (1) with ethyl ethoxymethylenecyanoacetate (2) gave amino(substituted vinylamino)methylenehydrazones (3) in high yields. Amino(monomethylamino)methylenehydrazones were more reactive than amino(dimethylamino)methylenehydrazones and, when the reaction temperature was raised, with or without addition of a base, directly produced 2, 3-dihydro- or 2, 3-dehydro[1, 2, 4]triazolo[1, 5-c]pyrimidine-8-carboxylates, depending upon the carbonyl component of the diaminomethylenehydrazone. Ketone amino(dimethylamino)methylenehydrazone gave no cyclized product. Similar condensation of diaminomethylenehydrazones with diethyl ethoxymethylenemalonate gave the linear products (7) and, when R² was hydrogen, the intermediate cyclized to dihydro-4-oxopyrimidinecarboxylate by exclusive intramolecular attack of N(4) on the ethoxycarbonyl carbon.

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Two new compounds, 2-chlorounguinol (1), C₁₉H₁₇ClO₅, and 3-ethyl-5, 7-dihydroxy-3, 6-dimethylphthalide (5), C₁₂H₁₄O₄, were isolated from the dichloromethane extract of culture filtrate of Emericella unguis (anamorph : Aspergillus unguis), together with nidulin (2) and unguinol (4). The structure of 2-chlorounguinol (1) was determined on the basis of spectroscopic investigations and X-ray crystallography, and that of the phthalide (5) was confirmed by spectroscopic investigations of several derivatives. 2-Chlorounguinol (1) is a fungal depsidone related to nidulin (2), originally isolated from E. nidulans. This is the first example of the isolation of a 3, 3-disubstituted phthalide as a naturally occurring compound.

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Electroreductive dehalogenation of 6-halopenicillanic acid derivatives was conveniently carried out to give the corresponding penicillanic acid derivatives, key intermediates in syntheses of various β-lactamase inhibitors, in good yields.

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Thiol proteinase inhibitors isolated from various tissues have a fairly conservative common amino acid sequence, Gln-Val-Val-Ala-Gly. We synthesized various kinds of Gln-Val-Val-Ala-Gly derivatives by the solution method. Z-Gln-Val-Val-Ala-Ala-pNA, Z-Gln-Val-Val-Ala-pNA and Z-Gln-Val-Val-pNA weakly inhibited the amidolytic activity of papain toward Bz-Arg-βNA and exhibited a stronger protective activity than corresponding Z-peptide methyl ester against thiol proteinase inhibitor (such as T-kininogen)-induced inhibition of papain.Suc-Gln-Val-Val-Ala-Ala-pNA exhibited more potent inhibitory activity toward papain than Z-Gln-Val-Val-Ala-Ala-pNA, but it did not show any protective effect. The circular dichroism spectra of the pNA derivatives and papain suggested that the pNA moiety of the peptide participated in binding with some part of the enzyme other than the catalytic site.

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5, 14-Bis(4-bromophenyl)diimidazolo[3²]metacyclophane (12) and 5, 14, 29, 38-tetrakis(4-bromophenyl)tetraimidazolo[3⁴]metacyclophane (13) as a higher homolog were synthesized by the one-pot coupling reaction of 1, 3-bis(2-isocyano-2-tosylethyl)benzene (3b) with 1, 3-bis(4-bromophenyliminomethyl)benzene (11). At -5°C, the proton nuclear magnetic resonance (¹H-NMR) spectrum of 12 strongly suggests the existence of two fixed conformers, i.e., syn and anti forms, on the NMR time scale.Moreover, on the basis of the variable-temperature (VT)-NMR spectra of 12 at various temperatures between 25°C and 100°C, the coalescence temperature (T_c) of the methylene proton signals is 80°C and the energy barrier (ΔG^〓) of the conformational change is determined to be 69.3kJ/mol, which is higher than those of the parent[3²]metacyclophane (4a) and dioxazolo [3²]metacyclophane (6a). The conformational rigidity of 12 is attributed to the further substitutions of bulky 4-bromophenyl groups on the imidazole moieties in addition to the annelations of two imidazole rings to the two methylene bridges of the [3²]metacyclophane ring.

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The Pd-peroxo complex (dioxygen)bis(triphenylphosphine)palladium [Pd(Ph₃P)₂O₂] caused epoxidation of olefins and oxidations of sulfides and sulfoxides in the presence of carboxylic acid derivatives. The Co-superoxo complex cobalt bis (salicylaldehyde)-3, 3'-diamino-di-n-propylamine [Co(Salpr)O₂] also oxidized sulfides to sulfoxides during the reaction with carboxylic acid derivatives. These oxidations were dependent upon the presence of a metal-dioxygen complex and an electrophile such as acyl cation. Metal-acylperoxide, generated in situ by the reaction of metal-dioxygen complex with a carboxylic acid derivative, could promote heterolytic cleavage of the O-O bond of dioxygen coordinated to metal to form a metal-oxo complex, which seems to be the ultimate species mediating the oxidations.

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Substrate specificity in the novel biotransformation from 2-pyrone derivatives to substituted benzoic acids by Macrophoma commelinae (IFO 9570) was investigated by means of feeding experiments with various compounds. Among them, 2-pyrone derivatives substituted by an electron-donating group at C-4, by an electron-withdrawing group at C-5 and by an alkyl group at C-6 were converted to the corresponding benzoic acid derivatives in fairly good yields. The C₃-unit precursors and intermediates were examined in stationary or shaking culture. Based on the experimental results obtained, a mechanism for this unique reaction is proposed.

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A total synthesis of (±)-descarboxyquadrone (5) starting from a bicyclo[3.2.1]octane (7;X=OH) is described. By a several-step sequence, the starting material was converted to a tricyclic compound (18), which was transformed to the target molecule, (±)-descarboxyquadrone (5), via a methoxymethylation.

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Two new hydrolyzable tannins, named camptothins A (1) and B (4), have been isolated from the leaf of Camptotheca acuminata (Nyssaceae) along with cornusiin A (2), gemin D (3), tellimagrandin I (5), tellimagrandin II (6), 1, 2, 6-tri-ο-galloyl-β-D-glucose (7) and 1, 2, 3, 6-tetra-ο-galloyl-β-D-glucose (8). Pedunculagin (9) was isolated from the fruit of C. acuminata. The dimeric structures of camptothins A and B have been established based on chemical and spectroscopic evidence.

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The Friedel-Crafts reaction of ethyl indole-2-carboxylate (1a) with acyl chlorides or acid anhydrides in the presence of Lewis acids was investigated in order to establish a preparative procedure for the corresponding ethyl 3-acylindole-2-carboxylates (4). Although monoacylation occurred successfully, the products were generally a mixture of ethyl 3-, 5-, and 7-acylindole-2-carboxylates (4, 5, and 6). The ratio of the yields of these three products varied greatly depending on reaction conditions and reagents used. A tendency that the 3-acylindole (4) was obtained as a main product was observed when a Lewis acid other than aluminum chloride was used as a catalyst and/or an acyl chloride derived from a weaker acid was employed, whereas a tendency for formation of the 5- and 7-acylindoles (5 and 6) was observed when aluminum chloride and/or an acyl chloride derived from a stronger acid was used. As to the 5-and 7-acylindoles (5 and 6), the yields of the former (5) were always much higher than those of the latter (6). The result indicates that ethyl 3- and 5-acylindole-2-carboxylates can be regioselectively prepared from a common substrate (1a) by changing the reaction conditions or reagents.

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A series of 1, 1'-bis-azolylarylmethanes has been prepared by reaction of azoles and their benzoderivatives with ortho-, and para-chlorobenzaldehydes, thiophene-2-carbaldehyde and furan-2-carbaldehyde in the presence of zinc chloride as catalyst. The antifungal activity has been tested, in vitro, against Botrytis cinerea, Aspergillus flavus, Mucor rouxii and Candida albicans. All 1, 1'-bis-azolylarylmethanes have minima inhibitory concentrations (MIC) higher than that of chlotrimazol, used as positive control.

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Various pyrimidine-5-carboxamides (14, 16, 18, 20, and 21) and (E)-β-(pyrimidin-5-yl)acrylamides (15, 17, 19, and 22)were synthesized as sparsomycin analogs, and their antitumor activity was examined by cell growth inhibition assay against mouse leukemia L5178Y cells in vitro.Synthesis was carried out by condensation of appropriate acids (4, 6, 10, and 12) and amino acid methyl esters (13) by the mixed anhydride method using isobutyl chlorocarbonate. The condensation product was converted to the corresponding acid and alcohol derivatives by hydrolysis and LiBH₄ reduction. The compounds having an ethylene linkage at the C-5 position and an ester moiety at the terminal amino acid functionality (15b, and 17b-g) exhibited remarkable antitumor activity.

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As part of the search for new antirheumatic agents, three types of 3-benzoylpropionic acid derivatives having a mercapto moiety in their structures were prepared, and tested for suppressing activity on adjuvant arthritis in Sprague-Dawley rats. A structure-activity relationship study showed that substitution on the phenyl ring contributed to the activity and the most favorable substituent was different in each type of derivative.

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Gomisin A (1) was incubated with rat liver S9 mix., and five products were obtained from the culture solution. The major product, met B (2), was identified as the demethylenated derivative of 1 by direct comparison with an authentic sample. The structures of four new products, met A-II (3), met C (4), met A-I (5), and met A-III (6), were determined on the basis of chemical and spectral studies.

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Among methanol extracts of 16 species of Indonesian crude drugs, that of Curcuma xanthorrhiza showed a prolonging effect on pentobarbital-induced sleeping time, a hypothermic effect in terms of rectal temperature and a suppressive effect on acetic acid-induced writhing when given by oral administration to mice. (R)-(-)-Xanthorrhizol was identified as a principle prolonging pentobarbital-induced sleeping time. The effect of the compound on sleeping time was demonstrated to be due to inhibition of cytochrome P-450 activity.

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Germacrone was identified as a hypothermic principle of Curcuma xanthorrhiza ROXB. When orally administered to mice, germacrone showed the following activities in addition to the hypothermic effect : prolongation of pentobarbital-induced sleeping time, suppression of spontaneous motor activity, suppression of acetic acid-induced writhing, and inhibition of stress-induced ulcer.

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From the dried aerial parts of Rabdosia longituba (MIQ) HARA, a new bitter diterpenoid, rabdolongin A (1), was isolated and its structure was elucidated on the basis of spectroscopic and chemical evidence. The absolute stereochemistry of rabdolongin B (=maoecrystal D) (6) was chemically established by correlation with trichokaurin (8) possessing known absolute stereochemistry.

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Four new pregnane glycosides and a known pregnane glycoside (named periplocoside D, E, L, M, and N, respectively), as well as a steroidal compound S-20, have been isolated from the antitumor fraction of Periploca sepium (Asclepiadaceae). Their structures were established by chemical and spectroscopic methods. S-20 was obtained from this plant for the first time.

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Four compounds, including two new flavonoids, were isolated from Si-pei licorice (licorice from the north-western region of China). The structures of the two new flavonoids, named glycyrrhisoflavanone and glycyrrhisoflavone, were (S)-7, 8'-dihydroxy-2', 2'-dimethyl-5-methoxy-[3, 6'-bi-2H-1-benzopyran]-4(3H)-one (6) and 3-[3, 4-dihydroxy-5-(3-methyl-2-butenyl)phenyl]-5, 7-dihydroxy-4H-1-benzopyran-4-one (9). Glycyrrhisoflavone was found to be one of the tannic substances by the measurement of the binding activity to hemoglobin (relative astringency). Licochalcone B (1) was isolated from the fraction which showed the highest binding activity to hemoglobin among the fractions obtained by centrifugal partition chromatography of the extract of Sinkiang licorice (licorice from Sinkiang in China). Licochalcone B also showed the highest activity as a radical scavenger in the experiment using 1, 1-diphenyl-2-picrylhydrazyl radical, among ten tested compounds obtained from several licorices. The order of the radical scavenging effects was the same as the order of the inhibitory effects on the 5-lipoxygenase-dependent peroxidation in arachidonate metabolism [licochalcone B (1)>licochalcone A (3)>>isoliquiritigenin (14)>liquiritigenin (13)].

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Taxacin, a new taxane derivative, and taxagifine were isolated from the seed of Taxus cuspidata SIEB. et ZUCC. (Taxaceae). The structure and stereochemistry of taxacin were confirmed on the basis of spectral data and X-ray diffraction analysis.

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Various enzyme species differing in copper content were formed when various amounts of Cu²⁺ were added to copper-free superoxide dismutase (E₂Zn₂SOD) and the apo-enzyme (E₂E₂SOD), and were separated by high-performance liquid chromatography. The three peaks, I, II and III, arising from the former were assigned as Cu₂Zn₂SOD, CuEZn₂SOD and E₂Zn₂SOD, respectively, based on the copper content and specific activity. The three peaks, A, B and C, from the latter were assigned as Cu₂Cu₂SOD+Cu₂CuESOD, CuEE₂SOD+Cu₂E₂SOD, and E₂E₂SOD, respectively.

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Competitive effectiveness and relative K_m values of polyunsaturated fatty acids were determined in the acyl-CoA : lysophospholipid acyltransferase systems in platelet membranes. Some CoA esters of fatty acids such as 18 : 2n-6 (linoleic), 18 : 3n-3(α-linolenic), 18 : 3n-6, 20 : 3n-6 (dihomo-γ-linolenic) and 20 : 5n-3 (eicosapentaenoic) were found in vitro to be relatively good competitive inhibitors of arachidonate (20 : 4n-6) incorporation into phosphatidylcholine, while in the acylation of lysophosphatidylinositol, 18 : 2n-6, 20 : 2n-6, 20 : 3n-6, 20 : 5n-3 and 22 : 4n-6 were relatively good inhibitors. When vegetable oil-supplemented diets rich in 18 : 2n-6 or 18 : 3n-3 were fed to rats, these fatty acids were converted to highly unsaturated fatty acids such as 20 : 4n-6 and 20 : 5n-3, and were esterified to phospholipids in platelets. The kinetic parameters determined in vitro were useful in predicting grossly the relative abundance of eicosanoid precursors (20 : 4n-6 and 20 : 5n-3), but not that of 18-carbon polyunsaturated fatty acids. It was found that arachidonate was conserved but n-3 fatty acids were excluded relatively more strictly in phosphatidylinositol than in phosphatidylcholine in platelets of rats on diets containing different proportions of 18 : 2n-6 and 18 : 3n-3.

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The rheological properties of carboxyvinylpolymer (CVP) hydrogels were evaluated using various methodologies. As CVPs, the series of Hiviswako (HVW) 103, 104, and 105 (denoted as H₁₀₃, H₁₀₄, H₁₀₅, respectively), and Carbopol (CP) 934, 940, and 941 (denoted as C₉₃₄, C₉₄₀, C₉₄₁, respectively) were used. The rheological measurements were carried out by the capillary tube method, oscillation method, and continuous shear method (Ferranti-Shirley viscometer). These measurements were mainly performed on the HVW series because their properties are not as well established as those of CPs.In the HVW series, the order of magnitude of intrinsic viscosities obtained by the capillary tube method was H₁₀₅>H₁₀₄>H₁₀₃ at all pH values examined This order agreed with that of the viscoelastic parameters obtained by the oscillation method and that of the viscosity obtained by the continuous shear method when the gels were in a non-neutralized state. However, the orders were reversed when they were partially neutralized by adding alkali.From these results, the gel structure of each polymer was presumed to be as follows. In the case of H₁₀₃, the polymer is rich in side chains or cross-links and takes a compact form in the nonneutralized state. When alkali is added to H₁₀₃, side chains are extruded into the water phase by the electric repulsive forces between carboxyl groups, and the polymer molecules become entangled with each other, so that the gel shows larger viscoelastic values. On the other hand, in the case of H₁₀₅, the polymer is poor in side chains and the addition of alkali has less effect on the viscoelastic properties than in the case of H₁₀₃ or H₁₀₄, due to the lack of entanglement of side chains. The viscoelastic properties measured in glycol solutions and the swelling rate for the HVWs supported the above hypothesis.As regards CP, C₉₄₁ showed almost the same properties as H₁₀₅. C₉₃₄ and C₉₄₀ showed similar properties to H₁₀₃ and H₁₀₄ respectively, although some differences were observed among them.

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(5-Methyl-2-oxo-1, 3-doxol-4-yl)methyl (6R, 7R)-7-[(R)-2-[(S)-alanyloxy]-2-phenylacet-amido]-3-[(5-methyl-1, 3, 4-thiadiazol-2-yl)thiomethyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate hydrochloride (KY-109) is a bifunctional prodrug designed to improve the oral absorption of the parent drug (KY-087), which is a cephalosporin with a broad spectrum of antibacterial activity.The mechanism of oral absorption of KY-109 was investigated in rats. An aqueous solution of KY-087 and a suspension of KY-106, which is esterified with a (5-methyl-2-oxo-1, 3-dioxol)methyl group at the C-4 carboxy group of KY-087, were poorly absorbed orally in rats. However, a 50% propylene glycol solution of KY-106 and an aqueous solution of KY-109 were well absorbed. KY-109 was rapidly hydrolyzed to KY-106 in the small intestinal contents, though it was hardly hydrolyzed in the stomach contents. FUrther, KY-109 was hydrolyzed to KY-087 via KY-106 in the gastrointestinal homogenate.From these results, the mechanism of the oral absorption of KY-109 can be speculated to be as follows. KY-109 is transferred into the small intestinal lumen without hydrolysis in the stomach, and is then hydrolyzed to KY-106 with the release of the alanyl residue. The resulting KY-106 is then transferred into the mucosal membrane, and hydrolyzed enzymatically with the formation of KY-087 along with acetoin. The resulting KY-087 is then transferred into the blood stream.

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Two cephem antibiotics, cefadroxil and cephradine, were microencapsulated with ethyl cellulose using a solvent evaporation process in liquid paraffin containing sorbitan tristearate as a dispersing agent. These products were administered to beagle dogs and biopharmaceutical evaluations were made of the sustained-release effect. First, Vallner's method was employed for the assessment of the sustained-release ethylcellulose microcapsules. The controlled release effectiveness was close to 0.8 for ethylcellulose microcapsules containing 70% cefadroxil and 60% cephradine. Second, assessments were made using pharmacokinetic parameters based on a model allowing for the gastric-emptying and intestinal transit rates of the drug itself and the solid state drug contained in the microcapsules using nonlinear least-squares regression. The results obtained showed that transfer of the rate-limiting step to the release process from the absorption process could be observed in microcapsules containing 70% cefadroxil but not in the case of microcapsules containing 60% cephradine. The release rates calculated on the basis of the above model correlated well with the release rate in dissolution tests at pH 6.8. Finally, a new nomogram was introduced for the design of sustained-release formulaitons in the future.

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Transcutaneous drug absorption is influenced by the physicochemical properties of both the drug and the vehicle. The effect of the vehicle is very important for the maximum drug effect. The effect of the vehicle can be considered from two standpoints, drug release and interaction with the skin, and therefore absorption of the vehicle itself may affect drug absorption. Because of the wide variety of vehicles mixed in ointments, it is difficult to measure the percutaneous absorption of all of them. It is important to study the relationship between the physicochemical properties of vehicles and the enhancement of absorption of the drug.In this experiment, a series of fatty acid-alcohol esters have been selected since they are frequently used as vehicles for drugs and cosmetics. The effects of the physicochemical properties of these vehicles on the percutaneous absorption of hydrocortisone butyrate propionate (HBP), a topical antiinflammatory corticosteroid, were examined. The partition coefficients (log P) of vehicles were determined by calculation.The gel vehicle was applied to the abdominal skin of anesthetized rats. The skin was excised after an appropriate interval and drug absorption was calculated from the unabsorbed drug amount. Drug absorption was enhanced by several additives. The physicochemical property values of additives that may result in maximum drug absorptions were calculated. The optimum values were approximately 12 for the partition coefficient and about 400 for molecular weight. Additives that have quite high hydrophobicity were found to be suitable for HBP (log P=3.3). When isopropyl myristate was used as an additive, after about 15h the absorption rate of HBP was found to have increased. It was suggested that isopropyl myristate has a direct effect on the barrier function. The physicochemical properties of the absorption enhancer affect not only the release of the drug from the vehicle to the skin, but also the interaction between the vehicle and the skin after penetration into the skin.

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The degradation of 4'-methylumbelliferyl 4-guanidinobenzoate (MUGB) was investigated in the presence of human serum albumin (HSA). HSA enhanced the rate of hydrolysis by a factor of 46.6 at pH 7.4. The pH-profile for the degradation of MUGB·HSA complex showed an inflection point at about pH 9.0, suggesting the involvement of a group with a pK_a of about 9. Inactivation of HSA with diethylpyrocarbonate (a histidine-specific reagent), and concomitant reactivation by hydroxylamine, indicated that histidine residues are involved in the esterase-like activity. Statistical analysis of the residual activity remaining in the partially modified HSA showed that only one histidine residue was critical for the activity among the 16 modifiable residues. In comparison with the HSA-catalyzed degradation of gabexate mesilate (GM) containing a guanidino group, the effects of site-specific ligands (warfarin, phenylbutazone and clofibric acid) on the HSA activity for MUGB degradation were examined. The results suggested that the active site for MUGB degradation is located far from the U-site and is different from the active site for GM degradation.

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The metabolism of ethyl eicosapentaenoate (EPA-E) was investigated in rats in vivo and in vitro with uniformly labelled ¹⁴C-EPA-E, and the antithrombotic properties of major metabolites of EPA-E in rabbits were examined.When ¹⁴C-EPA-E was administered orally to rats, eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) were identified in the liver as metabolites of EPA-E. These metabolites were incorporated mainly into phospholipids and triglycerides, and were found at the C-2 position of phospholipids and the C-1 and/or C-3 positions of triglycerides.When ¹⁴C-EPA coenzyme A (¹⁴C-EPA-CoA) was incubated with intact mitochondria, ¹⁴CO₂ was released and chain-shortened metabolites were detected by radio-high performance liquid chromatography. When ¹⁴C-EPA-CoA was incubated with intact peroxisomes, chain-shortened metabolites were detected as in the case of mitochondria.When potassium eicosapentaenoate (¹⁴C-EPA·K) was incubated with microsomes, DPA and DHA were produced as a result of chain elongation and subsequent desaturation reactions. When ¹⁴C-EPA-CoA was incubated with intact peroxisomes, DPA was produced in the presence of malonyl-CoA as a cofactor.EPA-E significantly decreased the incidence of thrombus formation and also decreased the length of thrombi in rabbits. Major metabolites of EPA-E, such as EPA, DPA and DHA, moderately decreased the incidence of thrombus formation.

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To clarify the mode of action of drugs on human erythrocyte membrane and the role of lipids in transmembrane transport of drugs, the cell and membrane were treated with phospholipase A₂ and cholesterol oxidase respectively, and the penetration of perazine and promethazine into the membrane and the membrane fluidity were estimated. It was found that 58.3% of phosphatidylcholine in the membrane was hydrolyzed. The fluidity of the membrane, estimated by the electron spin resonance method, was significantly enhanced by phospholipase A₂ treatment. When lysophosphatidylcholine and fatty acids produced were extracted by using albumin, the fluidity was greatly decreased. Although the treatment with cholesterol oxidase induced degradation of 24% of the cholesterol in the membrane, the fluidity was not altered. The amounts of these drugs that penetrated into the erythrocytes were significantly increased after phospholipase A₂ treatment, but dramatically decreased after the extraction of the products formed by phospholipase A₂, while the amounts were not significantly increased by cholesterol oxidase treatment. These resulted led us to postulate that phospholipids in the erythrocyte membrane are probably involved in the penetration of the two drugs, whereas the involvement of cholesterol is far less, and that the increased fluidity of the membrane lipids certainly contributes to the enhancement of penetration.

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Maltosyl (G₂)- and maltotriosyl (G₃)-cyclodextrins (CDs), synthesized from maltose or maltotriose and α-, β- or γ-CD with Pseudomonas isoamylase or Klebsiella aerogenes pullulanase were purified by high-performance liquid chromatography, and their solubilities in water and in various concentrations of methanol in water, specific rotations, and hemolytic activities were studied. G₂-and G₃-CDs, as well as glucosyl (G₁)-CDs, were much more soluble than each parent CD in water and methanol aqueous solutions. The hemolytic activities of the branched CDs decreased with increasing side chain length; CD>G₁-CD>G₂-CD>G₃-CD. The inclusion behavior of the branched CDs with slightly soluble or insoluble drugs in aqueous solution and in the solid state was examined by the solubility method and the differential scanning calorimetry. The complexation abilities of G₁-, G₂-, G₃-CD and their parent CD in a series appeared to be almost the same and the stabilities of complexes in water practically unaffected by the length of the side chain. However, the enhancement of solubility of poorly water-soluble drugs by branched CDs was much more marked than that by the parent CD.

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Solid dispersions in which the carriers were water-soluble agents have been investigated with the aim of improving the solubilities and dissolution rates of poorly water-soluble drugs. We have now examined the utility of barely soluble, but hydrophilic, phosphatidylcholine (PC) purified from hydrogenated soybean phospholipids as a carrier. As poorly water-soluble drugs, infomethacin (IM), flurbiprofen (FP) and ketoprofen (KP) were used.The X-ray diffraction patterns suggested an a amorphous state of IM when the molar ratio of IM was under 0.75.From the infrared spectra, it was considered that IM and PC had only a weak interaction with the carrier. The phase transition temperature of PC was depressed by IM and the degree of depression became larger with increasing molar ratio of IM. The solubility of IM in pH 7.0 buffer solution became 4.0mg/ml (5 times that of IM powder), when the PC solid dispersion with an IM molar ratio in the range of 0.50-0.75 was used. However, the IM concentration decreased with time and became 2mg/ml after 30h.FP and KP also had a weak interaction with PC and were present in the amorphous state, but this state was stable only when the molar ratio was under 0.50, which was lower that than in the case of IM. The solubilities of FP and KP from the PC solid dispersions were each about 1.5 times that from the powder.PC dissolved in water to the extent of 0.1-0.5mg/ml from the solid dispersions with IM, but the dissolution showed poor reproducibility, and no dissolution of PC was observed from FP and KP solid dispersions. Thus, the increased drug solubilities were considered to be due to the amorphous state of the drugs in the PC solid dispersions.

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A spray drying process was introduced into our method of particle size reduction by "solvation and desolvation" for the purpose of producing spherical particles with a large effective surface area. By solvate formation and successive desolvation in a single process of spray drying, preparation of spherical particles, which consist of primary fines, was achieved.

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In response to chemoattractants, rat polymorphonuclear leukocytes (PMNs)secreted latent gelatinase, which was predominant among PMN neutral proteinases such as collagenase, elastase and cathepsin G. The PMNs highly responsive to chemoattractants migrated earlier than other PMNs and secreted large proportions of their latent gelatinase, though their cellular content of gelationase was at a normal level. The gelatinase species secreted from PMNs were metalloproteinases and have the same molecular weights (96 and 230 kilodaltons) as those of proteinases stored in granules of PMNs. After treatment with an activator, the secreted gelatinase degraded bovine type IV collagen. From these results we hypothesize that there is a population of PMNs that actively migrates and secretes latent gelatinase in response to chemoattractants. The PMNs probably reach the vascular site near the inflammatory lesion faster than other PMNs and secrete large amounts of gelatinase to degrade basement membranes, resulting in the formation of a pathway for extravascular emigration of other PMNs.

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The following seven compounds were isolated from the photoreaction products of 2-naphthol in aqueous nitrite solution by silica gel chromatography and high performance liquid chromatography : 1-nitro-2-naphthol (Fp-2), 1-nitroso-2-naphthol (Fp-3), isocoumarin (Fp-4(1)), 5- or 8- nitro-2-naphthol (Fp-5(1)), a monoquinonoid dimer of 2-naphthol (Fp-5(2a)), a dinitro-2-naphthol (Fp-6(1)) and 1, 2-naphthoquinone. Among these compounds, the three nitro compounds, Fp-2, Fp-5(1) and Fp-6(1), and isocoumarin exhibited a weak mutagenicity towards S. typhimurium TA98 without S9 mix. Although no major mutagen was isolated, it was found that irradiation of the solution of non-mutagenic Fp-5(2a) with nitrite and of the mixed solution of 1, 2-naphthoquinone and Fp-2 without nitrite resulted in the formation of further mutagenic compounds. From these results, it is concluded that not only nitration but also quinone production is closely related to photochemical mutagen formation.

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A series of N⁶-alkyladenosine 3', 5'-cyclic phosphates (N⁶-alkyl cAMPs) (3) and N⁶-alkyl-8-benzylthio cAMPs (4) was synthesized from cAMP (1) and 8-benzylthio cAMP (2) by means of a one-pot reaction. This reaction proceeded by reductive alkylation in acetic acid with aldehydes and sodium cyanoborohydride. These cAMP derivatives were evaluated for inotropic and chronotropic effects on the isolated guinea pig papillary muscle and right atria. Several N⁶-alkyl cAMPs (3) were surprisingly more active than compounds 4 in these actions. Among them, N⁶-hexyl cAMP (3f) and M⁶-heptyl cAMP (3g) showed strongly positive inotropic effects (PIE) and moderately negative chronotropic effects.

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A new flavanone, named sophoraflavanone G (I), mp 173-175°C, C₂₅H₂₈O₆, and a new isoflavone, named sophoraisoflavone A (II), mp 235-237°C, C₂₀H₁₆O₆, were isolated from the root of Sophora moorcroftiana BENTH. ex BAKER (Leguminosae), together with sophoraflavanone B, licoisoflavone B, calycosin, l-maackiain and medicagol. The structures of I and II were established to be (2S)-5, 7, 2', 4'-tetrahydroxy-8-lavandulylflavanone and 3-(5'-hydroxy-2', 2'-dimethyl-2H-benzopyran-8'-yl)-5, 7-dihydroxychromone, respectively, on the basis of chemical and spectral evidence. The revision of the structures of nor-kurarinone and vexibinol is also described.

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Some properties of globulin polypeptides from Persicae semen were investigated. PR-A was separeated into acidic polypeptides A₁ and A₂, and basic polypeptides, a mixture of A₃, A₄ and A₅ (A₃-A₅), by ion-exchange chromatography in 6M urea. N-Terminal amino acids were determined as alanine for A₁, alanine and glutamine for A₂, and glycine for A₃-A₅ by the use of a gas-phase sequencer. As regards amino acid composition, A₁ and A₂ showed higher glutamine (and glutamic acid) content, and lower contets of basic amino acids (lysine, histidine and arginine) as compared to A₃-A₅. It seemed that PR-A exists as disulfide-linked A₁A₃-, A₂A₄- and A₂A₅- species with molecular weights of 65000, 59000 and 59000, respectively.

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A new theoretical expression is derived to estimate the rate and amount of the in vivo percutaneous absorption of drugs from in vitro skin permeation data. Based on two assumptions, that the skin permeation rate of the drug in the in vivo experiment is equal to that in vitro and that the drug elimination follows linear kinetics, the time course of the blood (total blood, plasma or serum) concentration of the drug after topical application could be expressed as a convolution equation. Based on the same concept, the permeation rates in in vitro and in vivo experiments are also compared by means of a deconvolution equation.In the present study, nicorandil was selected as a model drug. The simulated plasma nicorandil level vs. time curve from the in vitro permeation study was approximately fitted to the in vivo experimental data in hairless rats, particularly up to 10h. This method was valuable to estimate the time course of plasma concentration after topical application within the range of acceptable variation from the results of in vitro permeation experiments. Some difference between the observed and calculated plasma levels might be due to differences of the skin condition and so on in the in vitro and in vivo experiments.

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An antibiotic, grifolin, was synthesized in seven steps starting from orcinol by utilizing a biogenetic-type olefination.

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Site-selectivity in the reaction of 3-substituted pyridine 1-oxide with phosphoryl chloride was investigated. When a strongly electron-withdrawing group (e.g. CN, CONRR', COOR, or NO₂) was substituted at the 3-position, the reaction of 3-substituted pyridine 1-oxides with phosphoryl chloride yielded 3-substituted 2-chloropyridines as the main products.

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The palladium-catalyzed coupling reaction of 3-iodoindoles possessing an electron-withdrawing group at the 1- or 2-position with terminal acetylenes smoothly proceeded to yield 3-ethynylindoles. Similarly, the reaction of 3-iodobenzo[b]thiophene gave the expected products, but the reaction of 3-bromobenzo[b]furan provided resinous materials.

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A series of 1-heteroaroylpiperazines (V-VII, XI) was synthesized and examined for positive inotropic activities on the canine heart. The key intermediates, heteroarenecarboxylic acids (III, X), were prepared by two different methods, and were condensed with substituted piperazines to give 1-heteroaroylpiperazines V-VII and XI. Among them, quinazoline derivatives (XI) were found to have potent positive inotropic activities.

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A mutagenic principle in the basic fraction of the methanol extract from Sinomeni Caulis et Rhizoma (Menispermaceae) was isolated and identified as an oxoaporphine alkaloid, liriodenine.Liriodenine exhibited potent mutagenic activity towards Salmonella typhimurium strains TA98 and TA100 in the presence of liver homogenate (S9 mix) (10.9 and 90.7 revertants/nmol, respectively) and accounted for about 40% of the mutagenicity of the total methanol extract.

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3-Bromomethyl-6, 7-methylenedioxy-1-methyl-2(1H)-quinoxalinone was found to be a highly sensitive fluorescence derivatization reagent for carboxylic acids in high-performance liquid chromatography. Its reaction conditions were optimized for various linear C₃-C₂₀ saturated fatty acids. The reagent reacts with the fatty acids in acetonitrile in the presence of 18-crown-6 and potassium carbonate to produce the corresponding fluorescent derivatives, which can be separated on a reversed-phase column, Radial-Pak C₁₈ cartridge, by gradient elution with 35-100% (v/v) aqueous methanol. The detection limits for the acids were 0.2-0.8 fmol for an injection volume of 10μl.

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An epoxy intermediate, 2-(4-nitrophenoxy)oxirane (NPO), previously proposed to be a shortlived intermediate in the microsomal metabolism of 4-nitrophenyl vinyl ether (NPVE), was isolated by high-performance liquid chromatography and identified by mass spectrometric comparison with an authentic specimen. NPO decomposed to glycolaldehyde and 4-nitrophenol with a half life of 4.6min in 0.1M phosphate buffer, pH7.4, at 37°C. The hydrolytic decomposition was accelerated by the addition of rat hepatic microsomes, but the accelerating effect was reduced by the addition of 3, 3, 3-trichloropropene oxide, a microsomal epoxide hydrolase inhibitor.These results indicate that NPO is an obligatory intermediate in the microsomal conversion of NPVE to glycolaldehyde and 4-nitrophenol.

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We investigated whether fusogenic lipid-surfactant mixed micelles (MM), a solubilized lipid system, composed of linoleic acid (LA) and polyoxyethylated (60mol) hydrogenated castor oil (HCO60) as a nontoxic solubilizer, could potentiate the antitumor activity of bleomycin (BLM) against inherently BLM-resistant murine L1210 leukemia. In a Winn-type tumor-neutralizing assay in which mice were inoculated intraperitoneally with L1210 leukemia cells preincubated with test materials, treatment with BLM plus LA-HCO60 MM showed a significant prolongation of mouse survival time as compared with BLM alone or MM alone. Further, combined use of BLM and concentrated MM accomplished total tumor cell killing, and all animals survived tumor-free. From these results, we presume that MM can make BLM-resistant tumor cells sensitive to BLM.

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The circular dichroism (CD) of various steroidal α, β-unsaturated ketones having cyclic amino substituents near the enone system has been studied and the spectra provide significant information regarding the position and configuration of the substituents.

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