The infrared spectra of bis(L-serinato)nickel(II) dihydrate (Ni(L-ser)₂·2H₂O) and their isotopic complexes containing ⁵⁸Ni, ⁶²Ni and deuterium have been measured in the region between 4000 and 200 cm^-1. The shifts caused by nickel and hydrogen isotopic substitutions indicate that three bands at 342, 297 and 222 cm^-1 are Ni-liagnd stretching vibrations complicatedly coupled with Ni-O and Ni-N stretching vibrations. The conformational differences between gauche-anti and anti-gauche serinates in metallo-serinate complexes are characterized by the COO deformation vibrations. A normal coordinate analysis on the basis of a complete molecular conformation of Ni(L-ser)₂·2H₂O and an intermolecular force field reproduced well the observed frequencies and isotope shifts. In addition, the calculated result is consistent with both the empirical assignments and the observed frequency differences caused from the conformational differences.

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The infrared and Raman spectra of [bis(glycylglycinato)calcium chloride]_n and its isotopic complexes containing metal and hydrogen isotopes have been measured. A large isotope shift of more than 4 cm^-1 on ⁴⁰Ca and ⁴⁴Ca substitution has been observed in the infrared-active bands at 345, 267 and 242 cm^-1. These bands have been assigned to Ca-O antisymmetric stretching vibrations. The Raman-active bands at 305, 158 and 111 cm^-1 have been assigned to Ca-O symmetric stretching vibrations with no displacement of the calcium atom. The result of a normal coordinate analysis is consistent with both the empirical assignments and the experimental isotope shifts. These results indicate that Ca-ligand bond forces are almost similar to those of copper- and zinc-amino acid complexes.

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Two new derivatives of glycosyl mitomycin C, 7-N-{4-O-(β-D-glucopyranosyl and α-sialosyl)phenyl}-9a-methoxymitosanes, were synthesized, and their structures were elucidated by analysis of the nuclear magnetic resonance spectra. Field desorption mass spectrometry was successfully used for the confirmation of these structures. The cytotoxic, antibacterial, and antitumor activities of 7-N-(4-glycosylphenyl)-9a-methoxymitosanes were also examined.

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Chiral benzenesulfonamide titanium ate-complexes (4 and 8) were prepared from the lithium complexes (2 and 6) by treatment with titanium tetraisopropoxide. The diastereoselective reactions of aromatic carbaldehydes with 4 and 8 were performed, and the chiral o-(1-aryl-1-hydroxymethyl)benzenesulfonamides (3a-d and 7a-e) were obtained in 80-87% yields. The diastereomeric excesses (d.e.) of these products were evaluated as 62-82%. These compounds were also prepared from the lithium complexes (2 and 6), but the d.e. values were only 6-14% in this case.

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The geometry of the ethylidene side chain in vomilenine (1) was proven to be (19E) by the spectroscopic analysis of the synthetic intermediates from ajmaline (2) to vomilenine (1). The relative thermodynamic stability of vomilenine (1) and (19Z)-vomilenine (19), as revealed by their transformation into perakine (9), is discussed.

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Annelations of xanthines by the reaction of dimethyl acetylenedicarboxylate (DMAD) with 7-alkyl-8-amino-1, 3-dimethylxanthines (3) have been investigated. Treatment of 3 with DMAD in refluxing methanol gave 5-alkyl-1, 3-dimethyl-9-methoxycarbonyl-1, 2, 3, 4-tetrahydro-5H, 7H-pyrimido[1, 2-e]purine-2, 4, 7-triones (4) and 7-alkyl-1, 2, 3, 6-tetrahydro-1, 3-dimethyl-8-(1, 2, 4, 5, 6, 7-hexamethoxycarbonyl-3-azatricyclo[2.2.1.0^{2, 6}]heptyl)purine-2, 6-diones (10). However, when the reaction was run in N, N-dimethylformamide, 5-alkyl-1, 3-dimethyl-1, 2, 3, 4-tetrahydro-7, 8, 11-tris(methoxycarbonyl)-5H, 9H[1, 3]-diazocino[1, 2-e]purine-2, 4, 9-triones (11), 5-alkyl-1, 3-dimethyl-7, 8-bis(methoxy-carbonyl)-1, 2, 3, 4, 9, 10-hexahydro-10-(methoxycarbonyl)methylene-5H[1, 3]-diazepino[1, 2-e]purine-2, 4, 9-triones (12), and 5-alkyl-1, 3-dimethyl-1, 2, 3, 4, 9, 10-hexahydro-7, 8, 9, 10-tetrakis(methoxycarbonyl)-5H[1, 3]-diazepino[1, 2-e]purine-2, 4-diones (13) were formed.

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The reactions of 2-methylquinoline (7), 2-methylbenzothiazole (25), and related compounds 8-11 and 26-30 with benzoyl cyanide (1) or 4-nitrobenzoyl cyanide (2) proceeded via the cyanohydrin derivatives to afford the corresponding C-acylated products 12-17 and 31-36.

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A [4+2]-cycloaddition of quinazoline (2) and the 3H-1, 2, 3-triazolo[4, 5-d]pyrimidine 4 with enamines 1a-e resulted in ring transformation into the quinolines, 3a and 3c, and the 3H-1, 2, 3-triazolo[4, 5-b]pyridines, 5a-e, respectively. Similarly, the ynamine 13a cycloadded to 2 and its 4-cyano derivative 6, giving the quinolines, 14a and 14b, respectively.On the other hand, the 3H-1, 2, 3-triazolo[4, 5-d]pyrimidines 4, 15, 8, 16, 17, 18, and 19 underwent [2+2]-cycloaddition with the ynamine 13a, resulting in ring transformation into the corresponding 3H-1, 2, 3-triazolo[4, 5-d]-[1, 3]diazocines 21a-27. The 7-methoxy derivative 20, the 4-methoxy- and 4-cyano-1H-pyrazolo[3, 4-d]pyrimidines, 30 and 31, and the 6-cyano-9H-purine 36 also underwent [2+2]-cycloaddition with 13a to give the corresponding 3H-1, 2-3-triazolo[4, 5-b][1, 5]diazocine 28, 1H-pyrazolo[3, 4-b][1, 5]diazocines, 32 and 33, and 3H-imidazo[4, 5-b]-[1, 5]diazocine 37, respectively.The structures of the 1, 3- and 1, 5-diazocines, 21a and 28, were determined by X-ray crystallography.

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We describe the development of new common disaccharide intermediates bearing two amino and six hydroxyl groups that are chemically differentiated, and their application to syntheses of several lipid As.

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Nine polyhydroxysterols were isolated from the lipid extract of two Sclerophytum sp. soft corals collected in the Andaman and Nicobar Islands. Of these, three compounds (7a, b, and 8) had previously been isolated from the southern Japan soft coral Sarcophyton glaucum. Compound 1 was identified as lobosterol having a novel 6-keto-A/B-cis ring juncture. The structures of the five new compounds were determined as 25-deacetyllobosterol (2), (24S)-24-methylcholest-7-ene-3β, 5α, 6β, 25-tetrol 25-monoacetate (3), (24S)-24-methylcholest-22E-ene-3β, 5α, 6β, 25-tetrol (4), (24S)-24-methylcholestane-3β, 5α, 25-triol-6-one 25-monoacetate (5a) and its C-25 deacetoxy analog (6), from the spectral data and by chemical conversion.

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A detailed account is given of the syntheses of 9-alkyl-2-deuterioadenines (5b-d), adenosine-2-d (5e), and 2'-deoxyadenosine-2-d (5f) from the 9-substituted adenines 1b-f through cyclization of the aminoimidazolecarbox-amidine salts 9 or the corresponding free bases 8 with formic-d acid-d or 1-(formyl-d)-2(1H)-pyridone. Glycosidic hydrolysis of 5e with boiling 0.5N aqueous HCl afforded adenine-2-d (5a) in 77% yield. Peracid oxidation of 5a-e produced the corresponding 1-N-oxides (12a-e) in fair yields. Methylation of 9-methyl- (12b) and 9-benzyladenine-2-d 1-oxide (12d) and adenosine-2-d 1-oxide (12e) with MeI in AcNMe₂ gave the corresponding 1-methoxy derivatives (13b, d, e) in good yields. Dimroth rearrangements of 13b, 13d, and 13e via the free bases 14b, 14d, and 14e furnished the N⁶-methoxy isomers 15b, 15d, and 15e, but their isotopic purities were unsatisfactory. Unambiguous assignments of the purine-ring proton signals in the proton nuclear magnetic resonance spectra of the unlabeled adenines (1a-f, 2a-e, 3b, d, and 10e) have been made by comparison with those of the labeled species (5a-f, 12a-e, 13b, d, and 14e).

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An efficient synthesis of carbacyclin and its analogs (2-7) is described in which the stereospecific 1, 4-hydrogenation of a 1, 3-diene to an internal monoene plays a key role. That is, arene·Cr(CO)₃ complex-catalyzed 1, 4-hydrogenation of the dienes 13 and 58, obtainable from the Corey lactone in good yields, under high H₂ pressure afforded the exocyclic olefins 14 and 61 stereospecifically in excellent yields, and these intermediates were converted to therapeutically useful carbacyclin (2) and its analogs 3-7 in a usual way.

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A method for the stereospecific synthesis of trisubstituted exocyclic allylic alcohols is described. Using this methodology in combination with the Sharpless catalytic asymmetric epoxidation, an efficient synthesis of (R)-(-)-9, an important intermediate for anthracycline synthesis, has been accomplished in 36% overall yield from 14 with 93% ee.

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Carbazolequinone alkaloids, murrayaquinone-A (1a), and pyrayaquinone-A (2) and -B (3), as well as pyrano[3, 2-b]carbazolequinone 5, an isomer of 2 and 3, were prepared conveniently by the palladium-assisted intramolecular ring closure of the corresponding 2-arylamino-methyl-1, 4-benzoquinones 9a and 9i-k. A series of their analogues, 6-, 7-, and 8-substituted 3-methylcarbazole-1, 4-quinone derivatives 1b-g and 2-methylcarbazolequinones 6a-g corresponding to 1a-g, was also prepared in the same manner. Comparative analysis of the carbon-13 nuclear magnetic resonance spectra was found to provide useful information for the structural assignment of either 2- or 3-methylcarbazolequinones.

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8-Fluorocarbapenem derivatives having various C-3 side chains were synthesized to study for the structure-activity relationship of carbapenems by in vitro biological evaluation. The introduction of fluorine at C-8 of racemic PS-5 led to slight improvements of the antimicrobial activity and the stability to renal dehydropeptidase-I. When D-cysteine was additionally introduced to the C-3 position of (±)-8-fluorocarbapenem, the diastereomeric separation of the 8-fluorocarbapenems became feasible. As expected from penicillins and cephalosporins, (+)-8-fluoro-3-D-cysteinylcarbapenem (+)-7a was antimicrobially active, whereas (-)-7b was inactive. It is worth noting, however, that (+)-7a was significantly more sensitive to renal dehydropeptidase-I than (-)-7b. Irrespective of the presence of fluorine at C-8, basic S-side chains at C-3, such as the pyridyl and pyrrolidyl groups, significantly improved in antimicrobial activity and dehydropeptidase-I stability. The combination of 8-fluorination with C-3 basic side chains in 7c-g resulted in a marked improvement of antimicrobial activity and dehydropeptidase-I stability.

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With partially purified kidney dehydropeptidase-I (DHP-I) preparations, the hydrolysis kinetics of glycyldehydrophenylalanine (Gly-dPh) by DHP-I were found to be completely non-Michaelian, whereas those of PS-5 and imipenem were composed of at least two-phase reactions which were also observed using Bacillus cereus type II β-lactamase. Thus the DHP-I stabilities of 34 PS-5 carbapenem derivatives which were synthesized by chemical modification at the C-3 side chain of PS-5 were examined in vitro using fresh mouse, dog and human DHP-I preparations, and are tentatively expressed in reference to the DHP-I stabilities of PS-5. The in vitro DHP-I stability of PS-5 was significantly improved by introduction of basic side chains and cysteines at C-3. More particularly, the D-cysteinyl side chain was more stable relative to DHP-I than the L-cysteinyl. In vivo, however, the degree of improvement of the DHP-I-stability by chemical modification at C-3 was not sufficient enough to establish therapeutically effective levels of serum concentrations and urinary recoveries of the carbapenem derivatives after parenteral administration.

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Procedures for the estimation of the novel quantitative structure-activity relationship (QSAR) descriptor σ_S°, representing the contributions from both dispersion and repulsion interactions, have been presented for the poly-substituted benzene derivatives.Observed values σ_S° for C₆H_6-nR_n (R=F, Cl, Me, Et : n=2-6)can be given by the equation σ_S°(R_n)=a log n+b, where the slope a and the intercept b are also linear against σ_S°(mono). Consequently, the slope a and the intercept b estimated from σ_S°(mono) and log n afford σ_S° for poly-substituted benzene derivatives having an optional set of substituent groups. The values thus obtained agreed well with the observed ones, and were also found to be linear against Σσ_S°(mono), where the correction of the number of symmetry should be taken into account.Furthermore, the net increases of polarizabilities Δα for the tetra-, penta-, and hexa-substituted benzene series from benzene reference are approved to be expressed by the linear relation against ΣΔα(mono).

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Several benzothiazolyl, imidazobenzothiazolyl, benzothienyl, benzothienopyrimidinyl and quinazolinyl 4, 5-dihydro-3(2H)-pyridazinones were synthesized and examined for cardiotonic activity in anesthetized dogs after i.v. administration. Among them, 4-methylamino-7-(2, 3, 4, 5-tetrahydro-5-methyl-3-oxo-6-pyridazinyl)quinazoline (36) showed potent and long-lasting inotropic activity (relative potency=2.11, milrinone=1). The activity of 36 was more potent than indolidan (2) (relative potency=1.53) which is one of the most potent inotropic agents to date.

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This paper describes the basic operating characteristics in perceptron-type neural networks, especially when applied to structure-activity relationships (SAR). It was shown that the neural network has outstanding abilities in both classification and fitting. The operation of the neural network is basically carried out in a nonlinear manner. This nonlinearity brings forth merits as well as a small number of demerits. Problems with the operation of the neural network are pointed out and discussions are aimed at solutions.

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A series of 4-alkoxy-2-(1-piperazinyl)quinazoline derivatives was synthesized and evaluated for its ability to reverse a scopolamine-induced learned impairment in a one-trial passive avoidance task (antiamnestic activity). 2-(4-Allyl-1-piperazinyl)-4-pentyloxyquinazoline (4) showed more potent antiamnestic activity than such reference compounds as aniracetam, idebenone and bifemelane at a wide dose range (1-30 mg/kg)). Compound 4 also exhibited potent anticonvulsive and antihypoxic activities, and was selected as the most promising nootropic candidate agent.

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A linear operation was introduced to the neural network. We also studied a method that gives correlation coefficients between input parameters and outputs. It was difficult to obtain these coefficients. Instead, we proposed a new index, the divided difference of output intensity with respect to the input parameter (δO/δx). The divided differences were obtained using an unsaturated sigmoid function as an output function of neurons, where a new learning method with the concept of "neuron fatigue" is introduced. The new techniques were applied to quantitative structure-activity relationships (QSAR) studies in carboquinones and benzodiazepines to compare the results with those by multiregression analysis. It was found that the divided differences work well and can produce the equivalent partial differential coefficients that are obtained by multiregression analysis.

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The role of the substituents at C3 and C8 of jesaconitine (1) on jesaconitine-induced analgesia and toxicity was examined. 3-O-Acetyljesaconitine (2), 3-O-anisoyljesaconitine (3), and 3-deoxyjesaconitine (6) showed dose-dependent analgesic action, and the potency of their compound-induced analgesia and toxicity was lower than those of 1. The most remarkable difference was found in the toxicity. The results indicate that the C3 hydroxy function of 1 participate in the induction of toxicity rather than of analgesia. 8-O-Linoleoyl-14-anisoylaconine (5), 8-O-methyl-14-anisoylaconine (7), 8-O-ethyl-14-anisoylaconine (8), 14-anisoylaconine (4) and 8-deoxy-14-anisoylaconine (9) showed lower activities than jesaconitine-induced analgesia and toxicity. The analgestic activity of 7 was almost the same as that of 8, but the toxicity of 7 was lower than that of 8. The analgesic activity of 9 was lower than that of 4, but the toxicities of both derivatives were not apparent. These facts indicate that the C8 function of 1 is important to the induction of analgesia and toxicity, and also that this function participates differently in the induction of the analgesia and toxicity. Subsequently, it was suggested that substitutents at C3 and C8 of 1 played important roles of the induction of the analgesia and toxicity, and that the modes of this participation were not the same in analgesia and toxicity.

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Effects of various cardioactive agents and a water extract of the pilose antler of Cervus nippon var. mantchuricus on periodic beating of cultured myocardial cell sheets were examined by using an image analyzing system. Norepinephrine increased the beating rate and the beating amplitude, whereas digoxin and forskolin enlarged only the beating amplitude. Verapamil and propranolol decreased both the beating rate and the beating amplitude. The water extract of the pilose antler showed no remarkable effects in a standard medium (2.1 mM Ca²⁺). However, it significantly increased the beating amplitude when the beating was suppressed by replacement with a low calcium medium (0.5 mM Ca²⁺). A similar effect was found for 70% ethanol-soluble and -insoluble fractions of the extract.

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Eighteen novel triterpenoid saponins, named tragopogonsaponins A-R, were isolated from the roots of Tragopogon porrifolius L. (Compositae). The structures of these saponins were determined on the basis of spectral and chemical evidence. Seventeen of the saponins contained phenyl propionic acid derivative as ester moiety. Their structures were elucidated as oleananae-type triterpene saponins which have echinocystic acid as the aglycone moiety.

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It has been reported that an acetone extract of ginger and its fractions have anti-5-HT (5-hydroxytryptamine; serotonin) effects. In the present study, guinea pig ileum, rat stomach fundus and rabbit aortic strips are used in order to determined the constituents of fraction 2 which are responsible for anti-5-HT effect and to examine their pharmacological properties.The analysis of fraction 2-3 indicated that galanolactone, a diterpenoid, is one of the active constituents. In guinea pig ileum, galanolactone inhibited contractile responses to 5-HT with a pIC₅₀ value 4.93. pIC₅₀ value of galanolactone against the response to 2-methyl-5-HT, a selective 5-HT₃ agonist, in the presence of methysergide at 1×10^-5M was 5.10. pIC₅₀ values of ICS 205-930, a selective 5-HT₃ antagonist, were 5.30 and 7.49, respectively. The concentration-response curve of 5-HT was shown as a biphasic curve and galanolactone caused a selective shift to the right of the second phase.In the same preparations, the pIC₅₀ value of galanolactone and ICS 205-930 against the response to carbamylcholine (CCh) was 4.45 and 4.46.The inhibitory effect of galanolactone on the 5-HT response in the stomach fundus and aortic strips was less than that in the ileum.In addition, in the thoracic aorta precontracted with 50 mM K⁺, the relaxing effect of galanolactone was about 1/10 of that of papaverine.These results suggest that the anti-5-HT effect of galanolactone, a diterpenoid isolated from ginger, is related to antagonism of 5-HT₃ receptors.

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The decomposition of ginsenoside Rb₂ (Rb₂) in rat stomach (in vivo) and in 0.1 N HCl solution (in vitro) was investigated in detail. By treating with 0.1 N HCl, the acidity of which is similar to that of gastric juice, a part of Rb₂ was hydrolyzed to 20(R, S)-ginsenoside Rg₃. On the other hand, Rb₂ was little decomposed in rat stomach and a small quantity of an unidentified metabolite, which was different from the hydrolyzed products in 0.1 N HCl, was observed. The metabolite was separated into four compounds, which were identified by ¹H-and ¹³C-nuclear magnetic resonance and fast atom bombardment mass spectrometry. These compounds were determined to be 25-hydroxy-23-ene (IV), 24-hydroxy-25-ene (V), 25-hydroperoxy-23-ene (VI) and 24-hydroperoxy-25-ene (VII) derivative of Rb₂, respectively.In this study, it is suggested that 20(S)-protopanaxatriol saponins undergo hydrolysis of the C-20 glycosyl moiety and hydration of the side chain, on the other hand, 20(S)-protopanaxadiol saponins undergo oxygenation of the side chain.

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The analgesic principles from Aralia cordata THUNB. were identified with (ent)-kaur-16-en-19-oic acid (KA) and (ent)-pimara-8(14), 15-dien-19-oic acid (PA), respectively. Both compounds were significantly effective regarding analgesics, hypothermia, duration of pentobarbital-induced anesthesia, and depression of locomotor activity enhanced by methamphetamine at doses of 300 mg/kg (KA) and 500 mg/kg (PA) by oral administration.

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N-Methylpyridinium polymer column, which had the ability for resolution of albumin components such as mercaptalbumin and non-mercaptalbumin, was applied to the study of reaction of cis-diaminedichloroplatinum(II) (DDP) with bovine serum albumin (BSA). The peak of BSA-DDP complex was resolved from other albumin component peaks and the participation of mercaptalbumin in this complex formation was elucidated. The participation of nonmercaptalbumin and disulphide type dimer in the complex formation with DDP were also investigated.

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A new type of chemiluminogenic substrate for N-acetyl-β-D-glucosaminidase was synthesized. The substrate was obtained by incorporation of an enzyme-removable N-acetyl-D-glucosaminide group to the cyclic hydrazide moiety of an arylic hydrazide which contains a highly fluorescent benzofuran framework. Following enzyme-mediated hydrolysis, the substrate released the hydrazide that was subsequently subjected to chemiluminescent oxidation with hydrogen peroxide and a hemin catalyst in an alkaline buffer to generate light. The detection limit of the enzyme using this substrate was 0.6 I.U./I.

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To elucidate the mechanism of tumor necrosis factor (TNF) production, we analyzed proteins produed in macrophages sharing the epitope of TNF according to the priming and triggering of TNF production. Rabbit alveolar macrophages primed with Bacillus Calmette-Guerin (BCG) were isolated and cultured in vitro with ³⁵S-methionine, and the proteins produced were analyzed using anti-rabbit TNF monoclonal antibody. Primed with BCG, alveolar macrophages synthesized two proteins with molecular sizes of 50 and 17 kilodaltons (kDa) (p50 and p17) sharing the same epitope with mature TNF within the cells. These two proteins were released into the medium where other proteins were detected without TNF-activity. Cultured with lipopolysaccharide (LPS triggering), the primed alveolar macrophages released TNF-activity into the medium where p17 together with many larger proteins was detected by immunoprecipitation. In vitro translation of messenger ribonucleic acid (mRNA) from BCG-primed macrophages showed that primary TNF has a molecular size of 28 kDa (p28). These results suggest that active TNF of p17 is secreted when triggered via post-translational processing of the precursor molecules synthesized through priming with BCG.

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Two Ca²⁺-dependent membrane-binding proteins with apparent molecular weights of 70000 (calelectrin₇₀) and 32000 (calelectrin₃₂) were isolated from bovine liver using phenyl-Sepharose affinity chromatography followed by diethylaminoethyl (DEAE)-celllulose and Ultrogel AcA44 chromatographies. Limited proteolysis and immunological analyses indicated that calelectrin₃₂ was not a digested product from calelectrin₇₀. Both calelectrins bound to phosphatidylserine and to calmodulin in a Ca²⁺-dependent manner. Circular dichroism studies showed that the apparent α-helical contents of calelectrin₇₀ and calelectrin₃₂ were 25 and 40%, respectively and they underwent Ca²⁺ -dependent conformational changes. When the calelectrins were incubated with a brain microtubule preparation, they were phosphorylated by endogenous kinase(s) and phosphorylation occurred on serine residues. Moreover, calelectrin₇₀ showed an inhibitory action on endogenous kinase activity in the presence of Ca²⁺.

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Aqueous extracts prepared from procine kidneys (PKE) possess colony-promoting activity (CPA) which increases the number of granulocyte and macrophage colonies in semi-solid cultures of mouse bone marrow cells (BMC) in the presence of colony-stimulating factor (GM-CSF).PKE was totally inactivated by 15 mM N-ethylmaleimide, but was resistant to 5 mM dithiothreitol (DTT), 50 mM sodium metaperiodate and a mixture of diisopropylether-n-BuOH (3 : 2).The proportion of deoxyribonucleic acid (DNA)-synthesizing cells of the PKE-responsive cells was about one-half in comparison to those of CSF-responsive cells, as estimated using the hydroxyurea (HU) suicide method.Upon marrow preincubation with PKE in liquid culture for 24 h, the suicide rate of the colony forming unit in culture (CFU-C) by HU increased to 3 times compared to that of the control.Since cyclophosphamide (CY) induces a change in the number of CFU-C, the effects of PKE on BMC obtained from CY injected mice were investigated. On day 1, the number of PKE-responsive cells significantly increased by about 2.3 times in comparison with that of control, whereas the number of CFU-C per 1×10⁴ cells significantly decreased to about one-eighth of that of control.These results suggest that a sulfhydryl group(s) is required for the appearance of the colony-promoting activity of PKE, and glycoproteins, glycopeptides or hydrophobic components are not required; they also suggest that PKE may act on immature granulocyte/macrophage progenitors, which are youger than CSF-responsive CFU-C.

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Tetracycline resistance (Tc^R) plasmid pNS1, a deletion derivative constructed from staphylococcal plasmid pTP5, carries a tet determinant which specifies a Tc^R protein (TET) with a molecular weight of 50 kilodaltons (kDa). In order to express the pNS1-encoded TET as a fused product, a 0.8 kilobase pairs fragment containing 57.1% of tet determinant was inserted into a chloramphenicol resistance determinant. From the nucleotide sequence, it is deduced that the fusion protein (designated CAT'-TET') is a 53 kDa protein composed of 472 amino acids in which the 199 and 262 amino acids are derived from CAT and TET, respectively. Although the molecular weight of CAT'-TET' obtained from the results of sodium dodecyl sulfate polyacrylamide gel electrophoresis (42 kDa) was not in agreement with its predicted weight (53 kDa), the ratio of TET' segment to the fusion protein (22 kDa/42 kDa) corresponded almost exactly to that deduced from the nucleotide sequence (29 kDa/53 kDa). The expression of CAT'-TET' in Escherichia coli caused a rapid decrease in growth rate and in the number of viable cells. This result is thought to be due to the toxic effect of CAT'-TET' on the cell membrane.

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The effects of serine protease inhibitors, diisopropyl fluorophosphate (DFP) and phenylmethanesulfonyl fluoride (PMSF), on hemolytic activity of C6 were reinvestigated. C6 was inactivated in a range of 1-10 mM by both of the inhibitors as previously reported. Limited proteolytic digestion was also studied to elucidate the functional and structural domains of C6. The major fragments produced by trypsin, plasmin, or lysyl endopeptidase could not be separated unless disulfide bonds were disrupted, but Staphylococcus aureus V8 protease yielded several fragments, each of which was not linked by disulfide bond. When C6 labeled with [³H]DFP was subjected to limited digestion with V8 protease, a fragment with a molecular weight of 38 kilodaltons (kDa) was mainly labeled and other fragments of 53 kDa and 26.4 kDa were also faintly labeled, while fragment 35 kDa wasn't labeled, indicating specific domains reactive with DFP. On the other hand, when C6 with or without DFP treatment was digested with V8 protease and those fragments were incubated with C5 and subjected to sucrose density ultracentrifugation, fragments 53, 38, 35 and 27.5 kDa interacted with C5 in both cases. These results suggest that C6 modified by DFP can interact with C5, and the amino-terminal sequences of fragment 38 and 35 kDa suggest the binding domain of C6 with C5 takes place within the two short consensus repeats.

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Epidermal cells from newborn rat skin were cultured on type IV collagen-coated Millipore filter, and the transport of low density lipoprotein (LDL) labeled with Rhodamine B isothiocyanate (RB-LDL) through the cultured cell layer was examined. The transport of RB-LDL was dependent on temperature and biological energy. The transport was low at 17°C, but above 20°C, it became high with increase in temperature up to 37°C. The transport was markedly inhibited by the energy inhibitors 2-deoxygluose and NaN₃. Furthermore, the transport was saturable at the RB-LDL concentration of about 300 μg/ml and the activation energy of the transport was determined as 104.6 kJ/mol. No degradation product of LDL (apoprotein B) was observed during LDL transport through the cultured cell layer. The transport of RB-LDL through skin epidermal cells in culture is suggested to be mediated by transcytotic vesicles, but not by endocytosis and exocytosis via the lysosomal system, nor through cellular junctions.

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The structural features of ukonan C, the polysaccharide having remarkable reticuloendothelial system-potentiating activity obtained from the rhizome of Curcuma longa L., were investigated by methylation analysis, carbon-13 nuclear magnetic resonane, periodate oxidation and enzymic degradation studies. It is mainly made up of arabino-3, 6-galactan type and 4, 6-branched glucan type structural units. Degradation with α-amylase followed by the elimination of 1, 4-linked glucan side chains resulted in a marked decrease of its immunological activity.

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We examined the effect of glucose (Glu) and ascorbic acid (AA) on absorption and metabolism of isoniazid (INAH). After p.o. administration of INAH with or without Glu or AA, plasma concentration and urinary excretion of INAH and its metabolites, acetyl INAH (AcINAH), acetyl hydrazine (AcHy) and hydrazine (Hy), were determined by means of gas chromatography-mass spectrometry using stable isotope labeled compounds as internal standard. The combined administration of INAH with Glu or AA led to a significant decrease in the excretion of INAH and Hy, and a significant increase in the excretion of AcINAH and AcHy. The absorption amount of INAH was reduced to about one-half by the addition of Glu and the absorption rate of INAH markedly decreased in the case of co-administration of AA. Comparing the oral case with the results of i.v. administration, Glu and AA only affect the absorption process containing the first pass metabolism of INAH.

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The percutaneous absorption of elcatonin (EC), a hypocalcemic peptide, was investigated. A transdermal dosage form of EC was produced using a gel base, absorption enhancer and protease inhibitor, and applied to rats for 24 h. The combination of bile salt such as taurocholate and glycocholate, and n-octyl-β-D-glucoside or n-octyl-β-D-thioglucoside (OTG) exerted the potent enhancing effect on the absorption of EC, and a potent hypocalcemic effect was shown for 24 h or longer. The least level of plasma calcium was obtained 6 h or longer after application, suggesting the relatively rapid absorption of EC. The apparent bioavailability of EC in system 5 was 4.6%, this value being noteworthy in the percutaneous absorption of peptides. When the enhancing effect of taurocholate and OTG was separately measured, both agents acted additively on the absorption of EC. An EC ointment maintained the hypocalcemin effect after storage for 15 d at 40°C. The transdermal dosage form has the potential to be an efficient drug delivery system for Paget's disease and osteoporosis.

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Photolysis and hydrolysis of furosemide were studied in buffere solutions (pH between 1.2 and 12.0). Photolysis experiments were made at room temperature under a Daylight lamp^[○!R] or fluorescent lamps as artificial light sources and direct and indirect sunlight as natural light sources by changing the strength of illumination. The photolysis of furosemide was found to follow apparent first-order kinetics under both artificial and natural light sources. In acidic media, the rate of photolysis of furosemide was larger than those in neutral or alkaline media. The pH-rate profile for the photolysis of furosemide indicated that the rate of photolysis of unionized furosemide was much larger than that of ionized furosemide. A hydrolysis experiment of furosemide was made at 37°C in the darkened room. The hydrolysis of furosemide was also found to follow apparent first-order kinetics. Furosemide was stable in neutral or alkaline solutions. In acidic media below pH 3, hydrolysis of furosemide was found to be catalyzed by hydrogen ion with an acid catalyzed rate constant of 0.893 M^-1·h^-1.

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Poly(L-lactic acid) (L-PLA) microspheres containing 5-fluoro-2'-deoxyuridine (FUdR) or its ester prodrugs with saturated aliphatic acids (FUdR-Cn, n=2, 3, 4, 5, 6, 8, 10 and 12) were prepared. The physicochemical and biological properties and antitumor activity of the L-PLA microspheres were studied. The lipophilicity of FUdR-Cn was increased by prolonging its acyl-promoieties. FUdR-C5, FUdR-C6, FUdR-C8, FUdR-C10 and FUdR-C12 showed almost complete incorporation into the microspheres, while incorporation of hydrophilic FUdR and FUdR-C2 was poor. The sustained release of FUdR from the microspheres containing FUdR-C4, FUdR-C5 and FUdR-C6 was obtained in the presence of esterase, and higher antitumor activity against P388 leukemia was observed in vivo. On the other hand, the release rates of FUdR from the microspheres containing FUdR-C10 and FUdR-C12 were very small, and their antitumor activity was much smaller than that of the free prodrug suspension. Effects of the susceptibility to enzymatic hydrolysis and the physicochemical properties of prodrugs on the release profiles of FUdR from spheres were discussed.

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The release of medicine from solid dispersion which was prepared by evaporation after dissolving or suspending water-soluble medicine into an organic solvent was studied. Oxprenolol hydrochloride was used as a water soluble medicine. Eudragit RS, methylcellulose, ethylcellulose, polyvinylpyrrolidone, hydroxy propyl cellulose and pullulane were used as the polymers. These polymers and oxprenolol hydrochloride were suspended in or dissolved into ethanol under heating, and the ethanol in these solutions was evaporated to solid dispersion. Solid dispersion granules were prepared by grounding and sieving the solid dispersions obtained. The dissolution behavior of oxprenolol hydrochloride was studied by the dissolution test (JP XI).As a result, it was clarified that in a solid dispersion granule composed of 25% oxprenolol hydrochloride, 70% ethylcellulose and 5% hydroxypropyl cellulose, the dissolution behavior of oxprenolol hydrochloride from this granule was of a leaching type for the matrix and was not affected by pH. Furthermore, various dissolution behaviors could be obtained by changing the particle size and the ratio of the polymer in the granule. These results suggest that this granulating method by the evaporation of the solvent is useful in preparing a sustained release preparation.

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The change in fluidity by adding pentoxifylline to erythrocyte membranes was compared with that caused by S-adenosyl-L-methionine (SAM) by the method of electron spin resonance (ESR) spectroscopy. When SAM or pentoxifylline was added externally to the erythrocyte suspension (outside), the fluidity of the membrane bilayer was increased after incubation at 37°C. However, the fluidity change in the inner part of the bilayer was relatively small compared to that in its outer part. These fluidity changes were dependent on the incubation time and the temperature. When the erythrocyte suspension was preincubated overnight at 4°C in the presence of durgs (inside), the fluidity of the inner part of the membrane changed significantly. Nevertheless, that of the outer part of the lipid bilayer was not affected. Such an asymmetric fluidity change in the lipid bilayer was not observed by the addition of other xanthine derivatives such as caffeine, theophylline and theobromine. S-Adenosyl-L-homocysteine suppressed and MgCl₂ enhanced the increase of the membrane fluidity by SAM or pentoxifylline. Furthermore, the effects of SAM and pentoxifylline on erythorocyte deformability were determined by a filtering technique method. In increasing order the additive effects of SAM and pentoxifylline on the erythrocyte filterability were SAM (outside)<pentoxifylline (inside)<pentoxifylline (outside)<SAM (inside). These results suggest that pentoxifylline also affects the membrane fluidity through the enzymatic methylation of phospholipids.

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The mode of action of protopine on blood platelet aggregation was investigated in the metabolic system of arachidonic acid and in liberation of platelet activating factor using in vitro experimental models. Protopine inhibited the releases of arachidonic acid and platelet activating factor from platelet membrane phospholipids. Protopine also inhibited the conversion of prostaglandin G₂ to thromboxane A₂, as well as carboxyheptyl imidazole, a thromboxane synthetase inhibitor.These results indicated that protopine functions both as a phospholipase inhibitor and a thromboxane synthetase inhibitor. It is expected that protopine can be applied for treatment of thrombosis as an antiplatelet drug.

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The interaction between a thyroid hormone metabolite, 3, 3'-diiodo-L-thyronine(3, 3'-T₂) and bovine serum albumin (BSA) was investigated by the fluorescence method. The apparent binding constants and thermodynamic parameters were obtained assuming the equivalence and independence of the binding sites on the BSA molecule. The maximum binding was attained at near pH 8.5 and the apparent binding constant at pH 8.5 was 2.7 (0.2)×10⁵M<-1>. The standard free energy change, enthalpy change and entropy change were -7.36 (0.02) kcal mol^-1, -7.75 kcal mol^-1 and -1.51 e, u., respectively.

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Synthesis of optically active sesquiterpene alkaloids, patchoulipyridine and related compounds, was accomplished by application of a method for constructing cycloalkenopyridines by thermal rearrangement of O-2-butenyloximes.

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A new lignan glycoside, named isoeucommin A (I), and four known lignan glucosides, (+)-syringaresinol-O-β-D-glucopyranoside (II), phillyrin (III), (-)-olivil-4"-β-D-glucopyranoside (IV) and pinoresinol-O-β-D-glucopyranoside (V), were isolated from the leaves of Osmanthus asiaticus NAKAI (Oleaceae). The structure of I was determined to be (+)-medioresiono-4"-O-β-D-glucopyranoside on the basis of chemical and spectral data.

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A cyano group in 1, 2, 4-triaznes, regardless of its position, acted as an effective leaving group in reactions with carbanions. Thus, the reactions gave the corresponding substituted products in place of the compounds formed by addition reaction of carbanions to the cyano group. Grignard reaction of these carbonitriles is also described.

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Cycloaddition reaction of 3-vinylpyrroles, generated by the alkylation of 1-methyl-3-thioacetylpyrrole, with dienophiles provided functionalized indoles.

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Mannich bases of 5-hydroxynaphthalene-1, 8-carbolactone 1 were prepared from various secondary amines or bulky primary amines and formaldehyde.They were isolated in almost all cases as hydrochlorides. These derivatives were submitted to in vitro antifungal and cytotoxic assays. The antifungal assays were performed against three strains of yeasts and five strains of human pathogenic fungi. Two of the tested compounds, 2i and 2j, exhibited interesting antifungal activities against Candida albicans and Candida tropicalis. The cytotoxic activity was evaluated towards L 1210 leukemia cells. Almost all of the Mannich bases had shown significant activity against this tumor cell line as values of IC₅₀ &les;4 μg/ml are considered interesting. Only one derivative 2 developed better cytotoxicity than the parent compound 1.

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Two new oleanene glycosides 4 and 7 were isolated by treatment with CH₂N₂ during a separation procedure from the methanolic extract of Crotalaria albida HEYNE, and their structures were characterized as 3-O-β-D-xylopyranosyl (1→2)-β-D-galactopyranosyl (1→2)-6-O-methyl-β-D-glucuronopyranosyl sophoradiol and 3-O-α-L-rhamnopyranosyl (1→2)[β-D-glucopyranosyl(1→6)]-β-D-galactopyranosyl (1→2)-6-O-methyl-β-D-glucuronopyranosyl soyasapogenol B, respectively. Other compounds 1, 2, 3, 5 and 6 were identified as the uronic acid methyl esters of kaikasaponins I, III and III monomethyl ether, and soyasaponins III and I, respectively.

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