We measured the absorption anisotropies of bacteriorhodopsin (bR) within a purple membrane suspension after photo-excitation in the millisecond time range. The purple membranes used were isolated from Halobacterium salinarium grown at three different culture temperatures, 37.0, 43.0 and 47.5°C. For the membranes from the 37.0°C culture, the observed anisotropies at wavelengths of 410, 570 and 680 nm showed almost the same slow decay. The slow decaying of the anisotropies originated from the rotation of the membrane itself. Using the membranes from the 43.0 and 47.5°C culture, however, we found that the anisotropy change varied at each wavelength measured. In these cases, it is shown from detailed data analysis that 1) the rotational motion of photo-intermediates within the membrane is more restricted than that of non-excited bR and 2) the distorted arrangements of the proteins within the membrane remain, even after photo-intermediates return to ground-state bR. This restricted motion is probably caused by the conformational changes in photo-intermediates, which prevent the rotation of the monomer protein and/or lead photo-intermediates to bind with neighboring proteins.

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The hydrogenation of (E)-2-(trifluoromethyl)alk-2-en-1-ols catalyzed by Ru-2, 2'-bis(diphynylphosphino)-1, 1'-binaphthyl (Ru-BINAP) and Rh-BINAP was carried out with good enantiomeric excess (71-83% ee). Ru-BINAP-catalyzed hydrogenation converted 2-(trifluoromethyl)acrylic acid to the corresponding saturated acid whose esterification and reduction provided optically active 2-(trifluoromethyl)propan-1-ol in 80% ee.

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In a continuing study on resin glycosides of crude drugs originated from Convolvulaceae plants, we examined the seeds of Cuscuta chinensis. Two novel acylated trisaccharides named cus-1 and cus-2 were isolated, together with a mixture of resin glycoside-like compounds. Their structures were defined as α-L-rhamnopyranosyl-(1→3)-[2-O-(11S)-11-hydroxytetradecanoyl]-[4-O-(2R, 3R)-3-hydroxy-2-methylbutyryl]-α-L-rhamnopyranosyl-(1→2)-[6-O-acetyl]-D-glucopyranose and α-L-rhamnopyranosyl-(1→3)-[2-O-(11S)-11-hydroxyhexadecanoyl]-[4-O-(2R, 3R)-3-hydroxy-2-methylbutyryl]-α-L-rhamnopyranosyl-(1→2)-[6-O-acetyl]-D-glucopyranose, respectively. They are considered to be closely related to so-called resin glycosides in terms of structure and biosynthesis.

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3', 6'-Bis(benzyloxy)-2', 4'-dimethoxychalcones, which were derived from dibenzyl ether of 3, 6-dihydroxy-2, 4-dimethoxyacetophenone, were oxidatively rearranged with thallium(III) nitrate (TTN) in methanol to give 2-aryl-1-[3, 6-bis(benzyloxy)-2, 4-dimethoxyphenyl]-3, 3-dimethoxypropan-1-ones; these products were converted into 6-hydroxy-5, 7-dimethoxyisoflavones by hydrogenolysis followed by cyclization. The 5-methoxy group in the acetates of the isoflavones was selectively cleaved with 5% (w/v) anhydrous aluminum bromide in acetonitrile to give quantitatively the corresponding 5-hydroxyisoflavones, which were hydrolyzed to 5, 6-dihydroxy-7-methoxy-isoflavones. The acetates were also demethylated to 5, 6, 7-trihydroxyisoflavones with 30% (w/v) anhydrous aluminum chloride in acetonitrile at 70°C for 36-48 h. The spectral properties of these isoflanones were examined and some natural isoflavones were identified.

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From the medicinal foodstuff "kuwai", the tuber of Sagittaria trifolia L., four bioactive diterpene ketones, trifoliones A, B, C, and D, two diterpene glucosides, sagittariosides a and b, and a nitroethylphenol glycoside, arabinothalictoside, were isolated, together with six known diterpenes. Their absolute stereostructures were determined on the basis of chemical and physicochemical evidence with included the application of a modified Mosher's method and an exciton chirality method. Among the diterpene consituents, trifoliones A, B, C, and D exhibited inhibitory effects on the histamine release from rat mast cells induced by compound 48/80 and calcium ionophore A-23187.

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Total syntheses of two homerythrinan alkaloids, schelhammericine and 3-epischelhammericine, are described. Photocycloaddition of a dioxopyrrolobenzazepine to 1-methoxy-3-trimethylsilyloxybutadiene afforded, in a regio- and stereo-specific manner, the cyclobutane derivative, which was converted to a homoerythrinan derivative by utilizing a TBAF-induced 1, 3-anionic rearrangement. The product was transformed into the title alkaloids in several steps.

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Thirty-nine triterpenodis including two novel compounds, 17-epilupenyl acetate and ixerenyl acetate, were isolated from the dried aerial parts and roots of Ixeris chinensis, Compositae, and their structures were elucidated by spectroscopic analysis.

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Total syntheses of homoerythrinan alkaloids of 1(2)-alkene type, dihydroschelhammeridine and comosine, and those of 1, 6-dienoid type, schelhammeridine and 3-epischelhammeridine, were achieved. Total synthesis of the former alkaloids provided definite proof of their A/B-cis stereochemistry. In relatin to the stereochemistry, the conformations of erythrinan and homoerythrinan alkaloids are discussed.

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Synthesis of (±)-(4aα, 6α, 7α, 7aα)-hexahydro-6-hydroxy-7-methylcyclopenta[c]pyran-3(1H)-one [(±)-1] has been achieved through an 8-step route starting from 6, 7-dihydrocyclopenta-1, 3-dioxin-5(4H)-one (4). The identities of synthetic (±)-1 with abelialactone, Aglykon A1, and isoboonein permitted the unequivocal assignment of this common structure and the relative stereochemistry to these cyclopentano-monoterpene lactones.

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Methyl 13-acetyl-12-methoxy-8, 11, 13-podocarpatrien-18-oate, prepared from (+)-dehydroabietic acid, was converted into methyl 12-methoxy-7-oxo-5, 8, 11, 13-podocarpatetraen-18-oate (9) by a series of reactions : haloform reaction, decarboxylation, Jones oxidation, and dehydrogenation. Reduction of 9 with sodium borohydride, followed by treatment of the resulting 7-hydroxy compound with boron trifluoride etherate, afforded a rearranged ester, methyl 6-methoxy-1, 10-dimethyl-1, 2, 3, 4-tetrahydroanthracene-1-carboxylate. This was further converted into 6-methoxy-1, 1, 10-trimethyl-1, 2, 3, 4-tetrahydroanthracene (14) by means of the following reactions : lithium aluminum hydride reduction, pyridinium chlorochromate oxidation, and Huang-Minlon reduction. Compound 14 was finally converted into the desired orthoquinone (1) according to the procedure of Ghosh and Ghatak. The synthetic 1 was shown to be identical with natural umbrosone by spectral comparisons.

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Starting from benzo- or thienocycloalkaneacetic acids, we have prepared a series of 1-(3-p-fluorobenzoylpropyl)-4-(1-oxo-benzo- or thienocycloalkyl-2-ethyl)piperazines 8a-e containing both semirigid and linear butyrophenones pharmacophores. The affinities of these compounds for dopamine (D₂) and 5-hydroxytryptamine (5-HT_2A) receptors were evaluated in vitro in receptor-binding assays and in functional experiments. The ratios of pK_i's for 5-HT_2A/D₂ receptors may be useful for rapid screening of new compounds and assessing potential induction of extrapyramidal symptoms; ratio values ≥-1.12 (Meltzer's ratio) are predictive of an atypical antipsychotic profile. The new molecules had a ratio in the range of 0.96-1.11 while haloperidol showed a ratio of 0.93. The 2-piperazinoethyl thiotetralone derivative 8d (QF 0506B) with a ratio of 1.11 was the most active compund.

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Structure-Ca²⁺ antagonistic activity relationships of semotiadil (1) congeners having a benzothiazine cyclic system were studied quantitatively by the Hansch-Fujita method. A quadratic dependency of the activity on ClogP, a lipophilic descriptor, of terminal arylalkylamine moieties was suggested. A correlation between the dipole moment component of the 5'-substituted 2-phenylbenzothiazine parts and the potency was also suggested. Additionally, quantitative analysis was successfully shown for the 2-substituted 1 congeners. The results gave information about the mode of binding of 1 with Ca²⁺ receptor.

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Five metabolites of diethyl 4-[(4-bromo-2-cyanophenyl)carbamoyl]benzylphosphonate (NO-1886) (1) were synthesized to confirm their proposed structures. The metabolites (2-6) were found to be identical with the synthesized compounds. These metabolites were orally administrated to Triton WR-1339-induced hypertriglyceridemic rats, and the plasma levels of triglycerides were measured to estimate lipoprotein lipase activity. All the metabolites showed lower potency than NO-1886.

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Sodium 2-[[4-(3-methoxypropoxy)-3-methylpyridin-2-yl]methylsulfinyl]-1H-benzimidazole (E3810) and omeprazole inhibit gastric acid secretion through inhibition of the activity of H⁺, K⁺-ATPase present in parietal cell membrane vesicles, by chemical modification of SH groups in the enzyme molecule. In order to clarify the mechanism of the chemical modification, reaction products of E3810 and omeprazole with 2-mercaptoethanol under acidic conditions (pH 3, 4, 5, 6) were isolated by HPLC, and subjected to structural analysis by UV, ¹H-NMR and mass spectrometry. E3810 and omeprazole appeared to undergo two kinds of reactions, affording disulfide-type products (type I reaction) and sulfide-type products (type II reaction). The rates of these reactions were determined by HPLC, and the stability of the products in the presence and absence of glutathione was investigated. In the case of E3810, type I reaction was found to proceed faster than type II reaction at every pH value studied. The type I reaction of E3810 was faster than that of comeprazole. The rate of type I reaction decreased at pH 5 and 6, especially for omeprazole, and the contribution of type II reaction increased as the pH of the reaction mixture was increased. The sulfide-type modification products were stable, whereas the formation of the disulfide-type modification products was reversed by the action of endogenous SH compounds such as glutathione. These results suggest that higher inhibitory activity of E3810 against gastric acid secretion and facter recovery of the enzyme activity after inhibition by E3810 can be expencted, as compared with those of omeprazole.

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The suppressed voltammetric respones of Fe(CN)^3-₆ at a glassy carbon (GC) electrode anodized in 1-octanol is restored by addition of alkaline earth ions and this can be applied to the detection of such cations. A good dependence of the cathodic currents of Fe(CN)^3-₆ at a 1-octanol-modified GC electrode on the concentration of each cation (Ca²⁺, Mg²⁺, Sr²⁺. Ba²⁺) is obtained over the range 10 μM-1 mM. The slight increase in enhanced voltammetric response of Fe(CN)^3-₆ in the presence of Ca²⁺ following added MeOH ruled out an ion-extraction mechanism for the observed phenomena. The effects of Ca²⁺ upon the voltammetric behavoir of Fe(CN)^4-₆ and IrCl^2-₆ as well as Fe/(CN)^3-₆ at a 1-octanol-modified GC electrode were compared with those previously reported at a carbon microelectrode, suggesting that the suppression of the cathodic reaction of Fe(CN)^3-₆ and its elimination by the addition of alkaline earth ions are brought about through transformation of a macroelectrode into a pseudo-microelectrode by anodization in 1-octanol. This is strongly supported by the fact that similar phenomena occur at other chemically modified electrodes, providing that modification is controlled to give an effective surface area corresponding to that of a pseudo-microelectrode.

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Caraganaphenol A (1), a new tetrameric stibene, was isolated from the root of Caragana chamlagu LAMARK (Leguminosae) along with (+)-α-viniferin (2) and kobophenol A (3). The stereostructure of 1 was suggested using NMR techniques (¹H-detected heteronuclear multiple quantum coherence (HMQC), ¹H-detected heteronuclear multiple bond connectivity (HMBC), and nuclear Overhauser effect (NOE) difference spectra).

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A new triazol antifungal agent, (+)-2-(2, 4-difluorophenyl)-3-methyl-1-(1H-1, 2, 4-triazol-1-yl)-3-[6-(1H-1, 2, 4-triazol-1-yl)pyridazin-3-ylthio]butan-2-ol (MFB-1041), shows poor oral absorption and is practically insoluble in water (1.2 μg/ml). Solid dispersion systems with an enteric polymer such as hydroxypropylmethylcellulose phthalate (HP-55^<[〇!R]> and carboxymethylethylcellulose (CMEC^<[〇!R]>, and a nonenteric polymer, hydroxypropylmethylcellulose (Metholose^<[〇!R]> were evaluated to improve durg absorption and solubility. The oral bioavailabilities of these solid dispersions in beagle dogs were over 6 times higher than that of a suspension system with increasing drug solubility in an alkaline medium. X-Ray powder diffraction measurement of the solid dispersion showed a complete drug phase change from a cystal to an amorphous state. Further, from the results of a stability test, the preparations were stable in a desiccated condition and the absorption profiles also showed no change. From the results, it was suggested that the oral administrative preparation of MFB-1041 having a superior absorption profile and a high stability could be obtained by a drug phase change from a crystal to an amorphous state, especially in the spray-drying method using enteric polymers.

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In this study, the mechanism of heat transfer between gas and granule in fluidized bed granulation was investigated, and the granule growth rate was predicted using heat transfer and moisture balance measurements. First of all, the heat transfer coefficient between gas and granules in a fluidized bed was measured using granules of four different sizes, and the experimental data obtained over a wide range of granule Reynolds number were found to be expressed as Nu_p=2+0.6Re^1/2_pPr^1/3, where Nu_p, Re_p and Pr indicate granule Nusselt number, Reynolds number and Prandtl number, respectively. Secondly, a model in which the heat transfer and the moisture balance were taken into consideration was proposed to predict the moisture content and granule growth rate during granulation. It was also confirmed that the experimental results at various binder (water) flow rates and inlet air temperatures were in good agreement with those predicted from the thoery. As a result, the mechanism of the heat transfer was elucidated and the granule growth rate during granulation could be predicted with high accuracy.

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The mechanism of interactin between p-hydroxybenzoic acid esters (parabens) and polyoxyethylene cetyl ether (PCE) was studied by ultrafiltration, a fluorescence probing method and NMR spectroscopy. Apparent partition coefficients of parabens from methyl to butyl ester between the PCE micellar and aqueous phase increased logarithmically in proportion to the carbon number in the alkyl group of parabens. Changes in the chemical shift of paraben protons in the presence of PCE were also enlarged with the carbon number. Hydrocarbon proton signals of PCE were shifted in the presence of ethyl paraben, whereas the signal of oxyethylene protons was changed only at high concentrations of the paraben. In addition, the incorporation of parabens into PCE micelles brought about a decrease in the polarity of the palisade layer in the micelles. The interaction magnitude of ethyl benzoate derivatives with PCE tended to be correlated with the hydrophobility of the derivatives. The affinity of ethyl benzoate derivatives for PCE micelles, however, was affected by the possession or position of the hydroxyl group in the derivatives. The paraben molecules may thus be concluded to locate in the PCE micellar interior by a hydrophobic interaction between the alkyl chain of the paraben and the hydrocarbon core of the micelles, and to be distributed from the hydrocarbon core close to the oxyethylene layer to the core interior, as the carbon number in the alkyl group of parabens increased.

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The enhancing effects of heptakis(2, 6-di-O-methyl)-β-cyclodextrin (DM-β-CyD) and 2-hydroxypropyl-β-cyclodextrin (HP-β-CyD) on the percutaneous absorption of 4-biphenylylacetic acid (BPAA), a nonsteroidal antiinflammatory durg, in hydrophilic ointment were studied and compared with the parent β-cyclodextrin (β-CyD). ¹³C-NMR measurements suggested that the biphenyl group of BPAA is preferably included within the cavity of three β-CyDs. The three β-CyDs remarkably enhanced the release of BPAA from the hydrophilic ointment base and the in vitro cutaneous permeatio, depending on the increase in solubility of BPAA in the ointment base. Pretreatment of the ointment containing DM-β-CyD or HP-β-CyD onto the isolated skin of hairless mice, however, provided no effects on the skin permeation of BPAA. When propylene glycol was used as a vehicle, both the release rate and cutaneous permeation parameters showed no appreciable difference between BPAA alone and its HP-β-CyD complex, because the solubilities of BPAA and its HP-β-CyD complex were almost comparable in the vehicle. The present results suggested that the enhancing effect of β-CyDs on the percutaneous absorption BPAA can be mainly ascribed to an increase in the solubility of BPAA in the hydrophilic ointment.

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A chiral hydroxylated pyrrolidine derivative (4) and an N-(2-mercaptoethyl)pyrrolidine derivative (1c) were synthesized from D-ribonolactone and were used as chiral catalyst ligands in the reaction of diethylzinc and aldehydes. High asymmetric induction of up to 95% ee was observed in the addition to aromatic aldehydes using the chiral hydroxylated pyrrolidine derivative 4.

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The sequence of a peptide, trichokonin-II (TK-II), obtained from the culture broth of Trichoderma koningii OUDEMANS, was examined by ion-spray ionization mass spectrometry (ISI-MS), including the collision-induced dissociation (CID) technique. TK-II was concluded to be a mixture of three peptaibols, TK-IIa, TK-IIB, and TK-IIc.

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7-Methyladenine (6a) and 7-ethyladenine (6b) afforded the N(1)-oxides 7a, b in 78% yield each on treatment with m-chloroperoxybenzoic acid at room temperature; this is analogous to the previously reported N-oxidation of 7-benzyladenine (6c) to give the N(1)-oxide 7c. When treated with an excess of methyl iodide, ethyl iodide, or benzyl bromide in N, N-dimethylacetamide at room temperature, each of the 1-oxides 7a-c underwent alkylation almost exculsively at the oxygen atom of the N-oxide group. The products, isolated in good yields, were the salts 8d-l·HX of the nine 1-alkoxy-7-alkyladenines, in which either the O-alkyl or the N(7)-alkyl group is any one of methyl, ethyl, and benzyl. The UV and ¹H-NMR spectral data for 8·HX and some of their free bases 8 are presented.

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We evaluated the rate and mechanism of decomposition of cefazolin methyl ester (Δ³ ester) in phosphate buffer (pH 8.4).The decomposition of Δ³ ester proceeded simultaneously via 3 pathways. The first pathway is production of Δ² ester (rate k₁₂) by isomerization and production of Δ² acid (k₂₃) by hydrolysis of the Δ₂ ester. The second pathway is the cleavage reaction of the β-lactam ring and simultaneous elimination of the substituent at position 3 (k₁₄). The third pathway is production of Δ³ acid (k₁₅) by hydrolysis of the carboxylic ester at position 4.Kinetic analysis of each pathway was performed. The reaction rate constant from Δ² ester to Δ² acid (k₂₃) was the highest, and the reaction rate constant for the production of Δ² ester by isomerization (k₁₂) was similar to that for the elimination of the position 3 substituent by cleavage of the β-lactam ring (k₁₄). The rate of production of Δ³ acid by hydrolysis of the position 4 carboxylic ester was the lowest.These results show that Δ³ ester decomposition under a basic condition predominantly occurs through cleavage reaction of the β-lactam ring and Δ² ester producion by isomerization.Since the production of Δ² acid markedly depended on the production of Δ² ester by isomerization, Δ² ester production is the rate-limiting step of this pathway.

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2-Acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanonic acid (KE-298) is an antirheumatic agent. To elucidate the effects of optically active KE-298, we resolved the racemic acid and obtained the two optical isomers. (+)-KE-298 was converted to the 4-bromobenzyl ester derivative and the absolute structure was confirmed as (S) by X-ray crystallographic analysis.The pharmacological activities of the optical isomers and racemic KE-298 were compared by using the characteristic tests for KE-298. Though (+)-KE-298 showed a stronger suppressive effect on rat adjuvant arthritis than (-)-KE-298, no difference between the two isomers was detected in in vitro tests (enhancing effect on lymphocyte transformation, IL-1 antagonistic effect).

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The synthesis of dihydro furonaphth[1, 3]oxazine derivatives 3 was performed through a Mannich-type condensation between 2-cyano-5-hydroxy-3-methylnaphtho[1, 2-b]furan 2a, 1.5 eq of a primary amine and 3 eq of formaldehyde. Similarly, 2-cyano-5-hydroxy-3-methylfuro[2, 3-f]quinoline 2b gave the dihydro furo[1, 3]oxazinoquinoline compounds 4. Heating a mixture of the naphthofuran 2a, tert-bytylamine and formaldehyde at toluene reflux led to the furonaphthoxazine 3e, which decomposes to afford an o-quinonemethide intermediate 5. The latter was trapped with 1-morpholinopropene to give a dihydro furonaphthopyran derivative 6. All compounds 2, 3, 4 and 6 were assayed for in vitro cytotoxic activity toward L 1210, MDA-MB 231 and PC3 tumor cells. Among them, furonaphth[1, 3]oxazines 3b, 3c, and furo[1, 3]oxazinoquinolines 4c, 4b showed significant activity against L 1210 cells, while furoquinoline 2b was the most cytotoxic compound towards all three cell lines.

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A series of analogues of BQ-123 (1), a potent cyclic pentapeptide endothelin A receptor antagonist, with amino acids linked to the side-chain of the Pro residue via an ester linkage was synthesized. All analogues synthesized exhibited potent endothelin A receptor binding affinity similar to that of 1. Of the synthesized analogues, the Lys, Arg and N^α, N^ε-dimethyllysine analogues, 9d-f, exhibited about a three-fold attenuation of in vivo clearance compared with 1. In rats, these analogues exhibited a 3-fold-higher plasma concentration and a longer retention time in plasma as compared with those of 1. The attenuated in vivo clearance was thought to be a consequence of decreased extraction of the compounds from the blood via the hepatic anion transport system, which efficiently extracts 1 from the blood.

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Three cytotoxic cardenolides, acovenosigenin A 3-O-α-L-ramnopyranoside (1), euonymoside A (2) and euonymusoside A (3), were isolated from the woods of Euonymus alata (Celastraceae). The chemical structure of a new cardenolide, euonymusoside A (3) has been elucidated on the basis of extensive spectral analysis and enzymic hydrolysis to be acovenosigenin A (1β, 3β, 14β-trihydroxy-5β-cardenolide) 3-O-β-D-glucopyranosyl(1→6)-β-D-glucopyranosyl(1→4)-α-L-rhamnopyranoside. All three showed potent cytotoxic activity against some neoplastic cell lines.

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Inhibition mechanisms of staurosporine and H7 to cAMP-dependent protein kinase have been investigated through docking studies. For each molecule, the energetically most stable docking model was searched by using the conformationally flexible automatic docking program ADAM without any presumptions. The results explain well the observation that staurosporine does not bind to the enzyme competitively with H7, even though the two compounds competitively inhibit ATP binding.

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The circular dichroic spectra of a purple membrane (PM) in the presence of tetracaine (TTC) showed that neutral TTC lowered the exciton band intensity with a blue shift, whereas charged TTC resulted only in a lowering of the band intensity without the blue shift. This suggests that there is a difference in the mode of action on the PM between the two forms of TTC.

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Both enantiomers of the hexahydroazepine (7), key intermediates for the synthesis of (-)-balanol (1) and its enantiomer, were effectively synthesized via the shortest route involving stannyl radical cyclization of the aldehyde (4) connected with oxime ether followed by the optical resolution of the resulting azepine (7).

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The seven-membered S- and Y-ring systems of maitotoxin (1) were stereoselectively synthesized based on the rearrangement-ring expansion of the six-membered ethers having the mesylate group on the α-side chain.

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Two new secotriterpenoids 4, 23-bisnor-3, 4-secofilic-5-(24)-en-3-al (1) and 4, 23-bisnor-3, 3-dimethoxy-3, 4-secofilic-5(24)-ene (2) have been isolated from hexane extract of Adiantum cuneatum, and the structures were determined by extensive spectroscopic analyses

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Anodic oxidation of 23-hydroxyprotost-13(17)-ene fumished an unprecedented triterpenoidal skeleton, 17, 23-epoxyprotost-12-ene, while 23-acetoxyprotost-13(17)-ene was converted into 23-acetoxyprotost-13(17)-en-16-one.

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A new stereoselective synthetic route to triacetyl-L-erythro-C18-sphingosine has been developed by the combination of diastereoselective addition of thiophenol to chiral olefins and subsequent intramolecular substitution of the corresponding sulfonium group.

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