Panaxacol (1) and dihydropanaxacol (2), cytotoxic polyacetylenes isolated from the callus of Panax ginseng, were synthesized starting from D-(-)-diethyl tartrate. The absolute configuration of 1 was determined to be 9R, 10R and the absolute configuration at C-3 of 2 was tentatively assigned as 3S by the application of the R(+)-α-methoxy-α-(trifluoromethyl)phenylacetyl (MTPA) method.

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Synthesis of the methyl ester of AK-toxin II, a typical host-specific toxin, toxic to Japanese white pear, and fifteen diastereoisomers as its congeners was accomplished in optically active forms starting from vitamin C as a chiral starting material. Toxicity testing of these synthetic compounds revealed that the configurations of two chiral centers in the carboxylic acid part of the toxin have an important role in the toxicity.

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Heating of cycloalkanone-2-carboxylate with β-arylethylamine, and oxalylation of the resulting enamino-ester followed by Lewis acid-catalyzed intramolecular cyclization afforded various erythrinan-type heterocycles in excellent yields. This method is widely applicable not only to the synthesis of erythrinans but also to that of A-nor and A-homo analogs and ring-D variants of erythrinan. The alkoxycarbonyl group on the products was readily removed by a new decarbalkoxylation method (heating with magnesium chloride-dimethyl sulfoxide combination). Thus, starting from 2-ethoxycarbonyl-4, 4-ethylenedioxy-cyclohexanone, the 2, 8-dioxo-erythrinan derivative (35) was synthesized in several steps in high yield, and was readily converted to the natural Erythrina alkaloid, 3-demethoxyerythratidinone.

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ω-Carbamoylsulfoxides undergo a novel intramolecular Pummerer-type reaction with O-silylated ketene acetal in dry acetonitrile in the presence of a catalytic amount of zinc iodide to give α-thiolactams in good to excellent yields under nearly neutral conditions.

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As a synthetic application of the chiral monoester 2, prepared by pig liver esterase (PLE)-catalyzed hydrolysis of the corresponding meso dister 1, conversino of 2 into various cyclohexenone derivatives was examined. This paper describes the preparation of the isomeric cyclohexenones 6 and 7, potential intermediates for the synthesis of anti-hypercholesmic compactin (ML 236B) and mevinolin, under stereo- and regioselective control.

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The regioselectivity of O-methylation of the C6- and C11-hydroxyl groups of 2', 4"-O-bis(trimethylsilyl)erythromycin A (3, TMS-EM-A) and that in the case of 2', 4"-O-bis(trimethylsilyl)erythromycin B (4, TMS-EM-B) were examined in relation to the ease of deprotonation and the stability of the anion state. O-Metylation of 3 gave 11-methoxy-TMS-EM-A (5) and 6-methoxy-TMS-EM-A (6) in the ratio of ca.3 : 1, whereas that of 4 gave predominantly 6-methoxy-TMS-EM-B (7). To understand how the steric and electronic structures of EM-A (1) and EM-B (2) affect the selectivities, we carried out theoretical calculations using a semi-empirical molecular orbital method, MNDO. From the frontier electronic density of the lowest unoccupied molecular orbital (LUMO), it was suggested that the activities of deprotonation at the C11-hydroxyl groups of 3 and 4 are higher than those of the C6-hydroxyl groups. On the other hand, it was shown from the total energies of the molecules that the C6-O^- -derivatives (3a and 4a) of 3 and 4 are more stable than the C11-O^- -derivatives (3b and 4b). The difference of total energies between 4a and 4b is greater than that of 3a and 3b by 5.1kcal/mol, suggesting the possibility of hydrogen bonding between C11-O^- and C12-OH of 3b.

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An inseparable mixture of two new dibenz[b, d]oxocins combined with brazilin, named protosappanins E-1 (1) and E-2 (2), was obtained from the heartwood (Sappan Lignum) of Caesalpinia sappan L. (Leguminosae). They were separated from each other as isomeric hexamethyl ethers C₃₈H₃₈O<11>, [α]²³_D -80.8°(3) and [α]²⁴_D -9.6°(4). The mixture of 1 and 2 afforded brazilin and protosappanin B on reductive cleavage with sodium borohydride in alkaline methanol. On acid treatment, one of the hexamethyl ethers (3) yielded the other hexamethyl ether (4), l-11b-hydroxybrazilin trimethyl ether (13), and the dimethylacetal (11) of the trimethyl ether of protosappanin C. Compounds 1 and 2 were concluded to consist of protosappanin C combined with 11b-hydroxybrazilin through an acetal linkage and to be stereoisomeric in respect of the acetal carbon. The stereochemistries at the acetal carbons of 3 and 4 were determined by means of nuclear magnetic resonance (nuclear Overhauser effect) experiments.

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Two new tetranortriterpenoids, mahonin and secomahoganin, have been isolated from the cotyledons of seeds of Swietenia mahagoni. The structures of these compounds were determined by the use of two-dimensional nuclear magnetic resonance (2-D NMR) techniques (¹H-¹H correlation spectroscopy (COSY), ¹H-¹³C COSY, and ¹H-¹³C long-range COSY) and assignments of their ¹H-and ¹³C-NMR signals were performed. A possible biosynthetic pathway to these tetranortriterpenoids is proposed.

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The oxygenation reaction of (+)-camphor with a simple model reagent, Fe(MeCN)²⁺₆-H₂O₂-Ac₂O, for mono-oxygenase was investigated in connection with its bio-oxygenation. The products 1b, 2b, 3b, 5, 10, 11, and 12 were obtained.

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Dimethyl 2-sulfonyl- and 2-acyl-1, 2-dihydro-1-phthalazinylphosphonates (1a-e) were synthesized by the reaction of phthalazine with sulfonyl chloride or acyl chloride and trimethyl phosphite. The crystal structure of 1a was determined by X-ray analysis.

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A diarylheptanoid glycoside, named aceroside IX (1), C₃₀H₄₀O₁₂, [α]_D -63.5°, was isolated from the stem bark of Acer griseum and A. triflorum. Another diarylheptanoid glycoside, named aceroside X (2), C₂₅H₃₁O₈, mp 121°, [α]²¹_D -29.7°, and catechin were isolated from the stem bark of A. griseum and detected by thin layer chromatography in the case of A. triflorum. On acid hydrolysis 1 yielded a new diarylheptanoid, acerogenin G (3), C₁₉H₂₂O₃, which was identified as a ketonic derivative of (-)-centrolobol (5), and sugars, glucose and apiose. On partial hydrolysis, 1 gave aceroside X (2) and apiose. The sugar moiety of aceroside IX is bound to the phenolic hydroxyl at C-4" of acerogenin G (3) from the results of mass spectral analysis of 3 and its monomethyl ether (6), the latter of which was formed on methylation of 1 followed by acid hydrolysis. Acerosides (1) and X (2) were determined to be the 4"-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside and the 4"-O-β-D-glucopyranoside of acerogenin G, respectively, on the basis of carbon-13 nuclear magnetic resonancence spectral analyses in comparison with the spectrum of aceroside VIII (7).

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The aldol reaction of trimethylsilyl enol ethers (1-3) with various aldehydes in the presence of a catalytic amount of trimethylsilyl trifluoromethanesulfonate was investigated. With benzaldehyde (4) the β-hydroxycarbonyl compounds were obtained in good yields. The effect of a substituent on the benzene ring was also examined. Aliphatic aldehydes (11, 13, and 14) were found not to be suitable substrates for this catalytic aldol reaction. On treatment with tert-butyldimethylsilyl enol ethers (30 and 31) under the same conditions, benzaldehydes (4, 5, 7, 8) yielded the corresponding aldol products with good threo-selectivity.

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The palladium(0)-catalyzed condensation of aryl halides with the sodium salts of phenylsulfonylacetonitrile and diethyl cyanomethylphonate in dimethoxyethane gave the corresponding α-phenylsulfonylareneacetonitriles and diethyl arylcyanomethylphosphonates in good yields.The α-phenylsulfonylareneacetonitriles were easily desulfonylated with zinc to give the areneacetonitriles, and the arylcyanomethylphonates were converted to the alkylideneareneacetonitriles by means of the Horner-Emmons reaction.

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A chemical examination of polyphenols in Euphorbia helioscopia L. (Euphorbiaceae) has led to the isolation of four new hydrozable tannins named helioscopinins A (10) and B (9), and helioscopins A (11) and B (12), together with eight known tannins (1-8). On the basis of chemical and spectroscopic evidence, the structures of compounds 9-12 were established as 1, 6-(S)-hexahydroxydiphenoyl-3-O-galloyl-β-D-glucose, 1, 6-(S)-hexahydroxydiphenoyl-2, 4-(S)-dehydrohexahydroxydiphenoyl-3-O-galloyl-β-D-glucose, 1, 6-(S)-hexahydroxydiphenoyl-2, 4-(R)-elaeocarpusionoyl-3-O-galloyl-β-D-glucose and 1, 3, 6-tri-O-galloyl-2, 4-(R)-elaeocarpusinoyl-β-D-glucose, respectively.

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N-Aminopyrazoles were oxidized by electrolysis in CH₃CN to give 1, 2, 3-triazines and pyrazoles. The ratio of triazine formation increased when pyridine or H₂O was added to the solvent. Reaction mechanisms were investigated by the application of electrochemical methods.

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Ethyl 2-[(2-substituted ethyl)thio]-3-indolizinecarboxylates (1a-f and 5a-f) were deprotected with potassium tert-butoxide in N, N-dimethylformamide and the resulting potassium 2-indolizinethiolates were alkylated with various alkylating agents such as chloroacetone (3a), phenacyl bromides (3b-d), and nitrobenzyl bromides (3e, f) to afford smoothly the corresponding S-functinoalized indolizine derivatives (4a-r and 6a-r) in considerable yields. On the other hand, the similar reactions of 3-acetyl-2-[(2-substituted ethyl)thio]indolizines (7a-f) provided 3-metylthieno[2, 3-b]indolizine derivatives (8a-o), formed via the further intramolecular cyclization of the initially generated S-alkylated indolizines under the reaction conditions employed here. The functionalized indolizines (4a-r and 6a-r) obtained above could also be transformed to the corresponding thieno[3, 2-α]-(10a-r, 14a-d, and 15a, b) and thieno[2, 3-b]indolizine derivatives (11a-h and 12a-d) under various alkaline conditions.

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A full account is given of the chemical behavior observed for 7, 9-dialkyladeninium salts (16). On treatment with boiling 1N aqueous NaOH for 60min, 16a, b, d, e (X=I), 16c (X=Br), and 16f (X=ClO₄) rearranged to isomeric N⁶, 7-dialkyladenines (21a-f) in 50-91% yields. Treatment of the salts with 0.5N aqueous Na₂CO₃ at room temperature for 30-90min or with Amberlite CG-400 (OH^-) in H₂O at room temperature gave the ring-opened derivatives 22a-f (in the trans-formamide form) in 56-83% yields, and rate constants for the ring-opening reactions of 16a, b, d-g (X=ClO₄) and 16c (X=Br) leading to 22a-g were determined in H₂O at pH 9.84 and ionic strength 0.50 at 25°C. Cyclization of 22a with NaH in AcNMe₂ at room temperature or with boiling 1N aqueous NaOH produced 21a in 84% or 72% yield, respectively.In solution, the trans-formamides 22 seemed to transform slowly into the cis-formamides 23, attaining equilibria. The existence of such an equilibrium in D₂O or Me₂SO-d₆ at 25°C or in H₂O at pH 9.84 and ionic strength 0.50 at 25°C was kinetically confirmed in the case of 22a, and the mechanism of the rearrangement of 16 to 21 through 22 is discussed on the basis of the above kinetic results and Deslongchamps' theory of stereoelectronic control. On treatment with NaBH₄ in MeOH at room temperature, 16a (X=I) furnished the 7, 8-dihydro derivative 28 (84% yield), which slowly decomposed in H₂O at 60°C to give 22a in 49% yield.The 7, 9-dialkyladeninium salts (16) were found to be obtainable from N'-alkoxy-1-alkyl-5-formamidoimidazole-4-carboxamidines (9) through an alternative synthetic route : Alkylations of 9 with alkyl halides in HCONMe₂ in the absence of base, followed by hydrogenolysis of the N'-alkoxy group and cyclizatio (or vice versa) produced 16 in acceptable yields. In order to interpret the proton nuclear magnetic resonance spectrum of 22a, the 2-deuterated species 26 was also synthesized from 24 via 25 and 27.

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Five new monomeric carbazoles, named eustifoline-A (1), -B (2), -C (3), and -D (5) and furostifoline (6), and one dimeric carbazole alkaloid, murrastifoline-E (7), were isolated from the root bark of Murraya euchrestifolia collected in Taiwan in December, and their structures were elucidated by spectrometric means. Eustifoline-A (1) and -B (2) have a substituted pyran ring, ad eustifoline-C (3) having a geranyl side chain is considered to be a biogenetic precursor of 2. Eustifoline-D (5) and furostifoline (6) both have a furan ring system and were shown to be structural isomers. The new dimeric carbazole murrastifoline-E (7) was found to have the structure corresponding to deoxygenated murrastifoline-D (8) and to be an adduct of murrayafoline-A (9) with girinimbine (10).

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Silver tetrafluoroborate (AgBF₄) in trifluoroacetic acid (TFA) has been found to cleave the S-trimethyl-acetamidomethyl (Tacm) group or the S-acetamidomethyl (Acm) group without affecting other functional groups in a peptide chain. A newly isolated porcine brain natriuretic peptide-32 (pBNP-32) was synthesized by the combined use of the S-Tacm group and AgBF₄ deprotection. The synthetic pBNP-32 was obtained in better yield by the AgBF₄ procedure than by the standard I₂ procedure. THe syntehtic pBNP-32 has the highest chick rectum relaxant activity among the known members of the atrial natriuretic peptide-brain natriuretic peptide (ANP-BNP) families.Somatostatin was also synthesized by the Fmoc-based solid-phase method usign S-Tacm and AgBF₄. In this synthesis, the recently developed reagent tetrafluoroboric acid(HBF₄)was applied to cleave the peptide from the resin.

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A new 12a-hydroxyrotenoid, boeravinone C, has been isolated from the roots of Boerhaavia diffusa L. (Nyctaginaceae) and its structure including the absolute configuration was determined based on chemical and spectral evidence. The ¹H-nuclear magnetic resonance of boeravinone C showed unusual splitting patterns due to ABC spin systems. These splitting patterns were analyzed by a simulation method.

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Quantitative structure-activity relationship (QSAR) analysis of 3-phenyl-1-indanamines, 1-amino-4-aryltetralins, and 6-phenylpyrrolo[2, 1-α] isoquinolines has been performed for catecholamine-uptake inhibition activities, Similar equations were obtained for these series of congeners indicating a common tendency that the increase in hydrophobicity of the substituents on the primary phenyl ring (ring C) enhances the activity, and the important aromatic ring which interacts with the receptor is this ring C. It was also indicated that the effect of the introduction of the second N-methyl group differs depending on the series of congeners. These results were used to characterize a binding model for a pharmacophore, which comprised a phenyl ring and a basic nitrogen. This model defined the necessary three-dimensional features leading to the uptake inhibition, and degree of fitness with this model predicted the strength of the activity. Furthermore, it appeared likely that a substituent existing in a specific region of the inhibitor molecule causes a steric hindrance with the receptor site and reduces the activity.

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A series of 4, 4-diarylbutylamine and 4, 4-diarylbutanamide derivatives has been synthesized and evaluated for their antilipidperoxidation (ALP) activity and acute toxicity (LD₅₀). Some of them were found to have significant ALP activity.

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A series of 4-substituted 8-[(2-benzimidazolyl)sulfinylmethyl]-1, 2, 3, 4-tetrahydroquinolines was synthesized and examined for their (H⁺+K⁺)adenosine triphosphatase (ATPase)-inhibitory and antisecretory activities against histamine-induced gastric acid secretion in rats. Many compounds tested were potent inhibitors of (H⁺+K⁺)ATPase. Most compounds showed antisecretory activity. The antiulcer activity against water-immersion stress-induced gastric ulcer, aspirin-induced gastric ulcer and agstric necrosis induced by hydrochloric acid also were tested in the rat. Some of these compounds, in particular, 4-(N-allyl-N-methylamino)-1-ethyl-8-[(5-fluoro-6-methoxy-2-benzimidazolyl) sulfinylmethyl]-1ehtyl-1, 2, 3, 4-tetrahydroquinoline (XVIIx) were found to have potent activity. The structure-activity relationships are discussed.

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Acyloxyalkyl esters (2a-d), alkyloxycarbonyloxyalkyl esters (2e-g) and (5-methyl-2-oxo-1, 3-dioxol-4-yl)methyl ester (2h) of (5R, 6S)-2-(2-fluoroethylthio)-6-[(1R)-1-hydroxyethyl]penem-3-carboxylic acid (1) were synthesized. Enhanced oral absorption was observed in mice reflecting increased lipophilicity, compared with the parent 1 itself. Among them, the ester 2h showed a prolonged plasma level and a large area under the blood concentratino-time curve (AUC) in rats. These ester-type prodrugs of penem 1 in phosphate buffer (pH 6.86) were much more stable than those of cephalosporins which easily degraded via isomerization to Δ² cephalosporins.

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A series of quinazoline derivatives with various 4-heterocyclylpiperidino groups at the 4-position was synthesized and tested for cardiotonic activity in anesthetized dogs. Among them, several 6, 7-dimethoxyquinazoline derivatives showed potent cardiotonic activity.

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The alkylation of adenosine-3', 5'-cyclic phosphate (cAMP, 1) with alkyl bromides was investigated and various new alkylated cAMP derivatives, N⁶, N⁶, 2'-O-trialkyl cAMPs (2), N⁶, 2'-O-dialkyl cAMPs (3) and 2'-O-alkyl cAMPs (4), were prepared by a one step reaction without the introduction of a protecting group into 1. Compounds (2) were synthesized from 1 by treatment with alkyl bromides in the presence of NaH or potassium tert-butoxide in dimethyl sulfoxide. Compounds (3) were also synthesized from 1 under conditinos similar to those of the synthesis of 2 except for the use of MeONa as a base. Compounds (4) were prepared from 1 by treatment with alkyl bromides in the presence of 18-crown-6 in dioxane-aqueous KOH solution. N⁶, 2'-O-Dibenzyl cAMP (3e) was obtained from 1 by the same method as the preparation of 4. These new alkylated derivatives were evaluated for cardiotonic activity in vitro. Some of them showed weak positive inotropic effects and strong negative chronotropic effects. Thus, the presence of the 2'-hydroxyl group seemed to be assential for the appearance of potent positive inotropic activity caused by cAMP derivatives.

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Asymmetric synthesis of β-lactams by the [2+2]cyclocondensation of an imine (7) to chiral ketene species (2b, 4b, and 6c) bearing heterocycles derived from L-(+)-tartaric acid, (S)-glutamic acid, and (S)-serine was carried out. The reaction of 2b with 7 gave the trans-β-lactams with 74% diastereomeric excess, and cis-β-lactams were predominantly formed with high diastereomeric purity (up to 96%) when 4b and 6c were employed. Asymmetric synthesis of (3S, 4S)- and (3R, 4R)-1-benzyl-3[(benzyloxycarbonyl)amino]-4-hydroxymethyl-2-azetidinones (26 and 30g) using (R)-4b as a ketene species and the chiral imine (21) prepared from L-(+)-tartaric acid was also achieved.

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A series of 2, 3-dihydrobenzofuran-7-carboxamides, presenting a stabilized intramolecular hydrogen bond, was synthesized and evaluated in pharmacological models for antipsychotic activity. Among them, N-[(1-butyl-2-pyrrolidinyl)methyl]-2-methyl-5-sulfamoyl-2, 3-dihydrobenzofuran-7-carboxamide (15) showed an atypical neuroleptic profile similar to that of sulpiride (1) and more lipophilic properties than 1. Compounds 15 was 11 times more potent in antagonistic activity on apomorphine-induced hyperactivity in mice (ED₅₀=30mg/kg, p.o.) and stronger in potentiation of methamphetamine lethality in rats than 1, while it was as weak in inhibitory activity of apomorphine-induced stereotype in rats (ED₅₀>500mg/kg, p.o.) as 1. On the other hand, N-[(1-ethyl-2-pyrrolidinyl)methyl]-2-methyl-5-methylthio-2, 3-dihydrobenzofuran-7-carboxamide (30) showed classical neuroleptic profile with a potency comparable to haloperidol in antagonistic activity on apomorphine-induced hyperactivity in mice (ED₅₀=0.65mg/kg, p.o.). The structure-activity relationships were also discussed.

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Three tirucallane-type triterpenoids, niloticin, phellochin and melianone, were isolated from the fruits of Phellodendron chinense SCHNEID. (Rutaceae). The stereostructure of niloticin was determined based on spectroscopic and X-ray crystal structure analyses. Furthermore, a derivative of niloticin and two derivatives of melianone were also found. A possible biogenetic pathway in P. chinense is proposed : niloticin → melianone → limonoids, on the basis of isolation of the compounds in different oxidation states.

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Tetramethylpyrazine is one of the alkaloids contained in Ligusticum wallichii FRANCH. Ferulic acid is a phenolic compound contained in Ligusticum wallichii FRANCH and Angelica sinensis (OLIV.) DIELS. The present study was carried out to examine the effect of tetramethylpyrazine and ferulic acid and the combined effect of both compounds on spontaneous uterine contractions in rats in situ. Tetramethylpyrazine and ferulic acid showed an inhibitory effect on uterine movement when given perorally and intravenously, respectively. The combination of both compounds, at doses individually insufficient to inhibit, synergistically inhibited uterine contraction.It was found taht tetramethylpyrazine and ferulic acid inhibited uterine contractions and the inhibitory effect induced by the combination of both was due to the potentiation.

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The phloroglucinol derivatives isolated from Mallotus japonicus MUELL. ARG. (Euphorbiaceae) and their derivatives were evaluated for their capacity to produce cytotoxicity in HeLa cells and to inhibit the replication of herpes simplex virus type 1 (HSV-1). The characterizations of an isolated new acetophenone, malophenone (16), and cyclization products of mallotojaponin (1), isomallotochromene (17), mallotochroman (18) and isomallotochroman (19), were also described. All tested derivatives inhibited the replication of HSV-1 with ED₅₀ in the range of 88ng-48μg/ml. The derivatives 12 and 19 were found in vitro therapeutic index with 10.9 and 9.1, respectively, and they were considered to be active antivirals.

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An enzyme assay method for D(-)-3-hydroxybutyrate and acetoacetate involving acetoacetyl coenzyme A (CoA) synthetase was developed. To determine the concentration of D-3-hydroxybutyrate, it was oxidized with D-3-hydroxybutyrate dehydrogenase in the presence of nicotinamide adenine dinucleotide (NAD⁺) to acetoacetate, which was then converted to acetyl CoA via acetoacetyl CoA through the combined actions of acetoacetyl CoA synthetase and 3-ketothiolase in the presence of adenosine triphosphate (ATP) and CoA. To determine the concentration of acetoacetate, acetoacetyl CoA generated from acetoacetate with acetoacetyl CoA syntehtase was reduced to 3-hydroxybutyryl CoA with 3-hydroxyacyl CoA dehydrogenase in the presence of NADH. The amount of D-3-hydroxybutyrate or acetoacetate was estimated from the increase or decrease in the absorbance at 340 nm, respectively.The present assay method seemed to be accurate and quick. Furthermore, as to the assaying of D-3-hydroxybutyrate, the omission of hydrazine, which is included for the standard method, may be preferable for routine assaying.

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Preparative high-performance liquid chromatography on octadecylisilyl porous glass (pore size, 550Å) with acetonitrile-water as the mobile phase was applied for the isolation of saponins from Panax ginseng. In a single run, several milligrams of pure ginsenosides were obtained from 10g of roots of Panax ginseng. The method was simple, rapid and convenient and should be applicable to isolation of other saponins of crude drugs.

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The effects of glucocorticoids on deoxyribonucleic acid (DNA) synthesis were studied by using confluent cultured rat skin fibroblasts prepared by enzymatic dispersion and expanded up to passage 3. Dexamethasone caused the inhibition of the DNA synthesis stimulated by 10% fetal calf serum (FCS) in a dose dependent manner. Maximum inhibition (90%-100%) was achieved by the concentration of 10^-7M. A similar dose dependent inhibition was also obtained in the experiment using epidermal growth factor (EGF) (1ng/ml) as a stimulant. Dexamethazone (10^-7M) also inhibited the DNA synthesis stimulated by somatomedin C (100ng/ml) or platelet derived growth factor (1 half-maximum unit/ml) almost to control levels. Binding studies with ¹²⁵I-labeled EGF suggested that dexamethasone caused this ihibitory action without modulation of cell surface receptors for EGF.Furthermore, the effects of a variety of glucocorticoids on the DNA synthesis were studied to clarify the structural requirement of glucocorticoids for the inhibition of the DNA synthesis. The results showed that 11β-hydroxyl and 21-hydroxyl groups on the steroid nucleus were necessary for the inhibition of the growth factor-stimulated DNA synthesis. Meanwhile, the inhibitory action on the DNA synthesis was markedly diminished by the replacement of a 16α-methyl group by a 16β-methyl group in the presence of a bulky group at C-17 (e.g. 17α-valerate). For further elucidation of mechanisms of action of glucocorticoids on the inhibition of the growth factor-stimulated DNA synthesis, the relationships between the structural features of glucocorticoids and their binding ability to the glucocorticoid receptor ([³H]-dexamethasone-binding receptor) were studied. In most steroids (e.g. triamcinolone acetonide, betamethasone and hydrocortisone), the degree of the inhibition of DNA synthesis was almost correlated with the binding ability. But some steroids (e.g. progesterone, 11-deoxycorticosterone and betamethasone 17-valerate) which possesed no, or little, inhibitory action on the stimulated DNA synthesis showed a significant, or high binding, ability to glucocorticoid receptors. These results suggest that there are at least two kinds of structural requirement s for the inhibitory action of glucocorticoids on DNA synthesis, namely at the stage of receptor binding and the stage of post-receptor binding events.

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Aldos reductase and aldehyde reductase from the medulla of the rat kidney have been purified to homogeneity by using affinity chromatography, gel filtration and chromatofocusing. The molecular weights of aldose reductase and aldehyde reductase by sodium dodecyl sulfate (SDS)-polyacylamide gel electrophoresis were found to be 37000 and 39000, rspectively. The isoelectric points of aldose reductase and aldehyde reductase were found to be 5.4 and 6.2 by chromatofocusing, respectively. The major differences of amino acid compositinos between both enzymes were fonud in serine, alanine and aspartic acid. Substrate specificity studies showed that aldose reductase utilizad aldo-sugars such ans D-glucose and D-galactose, but aldehyde reductase did not use them. The K_m values of aldose reductase for various substrates were lower than those of aldehyde reductase. Aldose reductase utilized both reduced nicotinamide adenine dinucleotide phosphate (NADPH) and reduced nicotinamide adenine dinucleotide (NADH) as coenzymes, whereas aldehyde reductase utilized only NADPH. The presence of the sulfate ion resulted in a dramatic activation of aldose reductase whereas it did not affect aldehyde reductase activity. These enzymes ewre strongly inhibited by the known aldose reductase inhibitors. However, aldose reductase was more susceptible than aldehyde reductase to inhibition by the aldose reductase inhibitors.

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Two proteinases (I and II) from an intestinal luminous bacterium, Vivrio logei strain CPM-D3, were purified. The molecular weights of the proteinases I and II were estimated to be 62000 and 54000, respectively. These enzymes were most active at pH 9.0 and 60°C (proteinase I) and 50°C (proteinase II), respectively. These enzyme activities were inhibited by orthophenanthroline, but not by ethylenediamine-tetraacetic acid and phosphoramidon. Metal ions such as Cu²⁺, Hg²⁺ and Ni<2+> also inhibited these enzyme activities. Both enzyme activities were not affected by heat treatment at 100°C for 30min.

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The effects of various synthetic triamines having a general structure, H₂N(CH₂)_xNH(CH₂)_yNH₂, where x=2-5 and y=2-8 (abbreviated, x-y; with 3-4 being spermidine itself), on poly(U)-directed polypeptide synthesis of Escherichia coli and on growth of its polyamine-requiring mutants were examined in comparison with those of spermidine. Except for 2-2 and 2-3, all of the triamines stimulated more or less polypeptide synthesis at suboptimal Mg²⁺ concentrations, but the Mg²⁺ concentration required for the maximal stimulatory effect was different for each triamine. The degree of maximal stimulation caused by 3-3 (norspermidine), 4-4 (homospermidine), or 4-5 was nearly comparable with that by spermidine. The acetylspermidines were inactive, however, they inhibited the spermidine-stimulated polyphenylalanine synthesis. Many of the triamines examined reduced the ratio of leucine to phenylalanine incorporation into polypeptides during poly(U)-directed translation, and the degree of this effect did not necessarily correspond with that of the stimulatory effect. Moreover, 2-4, 2-5, 3-3 and 4-4 could stimulate the growth of a polyamine auxotroph of E. coli, MA 261, as effectively as did spermidine. However, 3-3 was the only triamine which could fully replaced spermidine in promoting growth of a mutant strain, KK 101, which is more dependent on polyamines than MA 261. Thus, these results demonstrated that some synthetic triamines were as active as spermidine in eliciting these effects, and also that there were some differences among these effects in the structural requirement for triamine.

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Sulfhydryl compounds significantly accelerated the hydroxylation of phenylalanine by stimulated polymorphounclear leukocytes. The reduced form of glutathione (G-SH) was most effective. The hydroxylation reaction in the presence of G-SH was largely prevented by superoxide dismutase and hydroxyl radical scavengers. The results suggest that a much faster production of hydroxyl radical may occur in a reaction mixture containing both G-SH and stimulated polymorphonuclear leukocytes than in that containing stimulated polymorphonuclear leukocytes alone.

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The effect of Zn²⁺ on the O^-₂ generation and change in intracellular Ca²⁺ concentration ([Ca²⁺]_i) of rat peritoneal neutrophils was studied. Zymosan (serum-treated zymosan (STZ))-induced O^-₂ generation was inhibited by Zn²⁺ at concentrations as low as 10μM. A large amount of the inhibition was observed in the absence of extraceullular Ca²⁺ but the inhbition could not be restored by increasing the extracellular Ca²⁺ concentration, indicating that Zn²⁺ does not necessarily inhibit the O^-₂ generation competitively with extracellular Ca²⁺. In the absence of extracellular Ca²⁺, Zn²⁺ inhibited STZ-induced transient increase in [Ca²⁺]_i in the concentration range that evoked a marked inhibition in the O^-₂ generation. On the other hand, Zn²⁺ did not inhibit significantly STZ-induced uptake of ⁴⁵Ca²⁺ from extracellular medium by the cells.From these results, it is suggested that Zn²⁺ inhibits STZ-induced release of Ca²⁺ from intracellular strage sites, resulting in the suppression of the activation mechanism of neutrophils.

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The alteration in bone metabolism at different ages was investigated by estimating glucose consumption and adenosine triphosphate (ATP) content in a culture system of bone tissue from 3- and 30-week-old rats. The femoral-diaphyseal tissue was removed and cultured for periods up to 48 h in Dulbecco's Modified Eagle Medium. Bone tisse was incubated at 37°C in 5% CO₂/95% air in a medium containing either vehicle and zinc sulfate (10^-6-10^-4M). The medium glucose consumed by bone tissue clearly increased in a 48 h-culture in 3-week-old rats, while the increase in 30-week-old rats was slight. The presence of zinc culfate (10^-6 and 10^-5M) caused a significant increase in bone glucose consumption in 3- and 30-week-old rats. ATP content in cultured bone tissue from 30-week-old rats fairly fell in comparison with that from 3-week-old rats. Bone ATP contents in 3- and 30-week-old rats were significantly increased by the presence of zinc (10^-4M). The present findings suggest that bone energy metabolism deteriorates with increasing age, and that zinc has a stimulatory effect in elderly rats.

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For the purpose of obtaining liposomes with long circulation time in blood, we synthesized 1-O-palmityl-D-glucuronic acid (PGlcUA) and incorporated it into the liposomal membranes. The clearance of the PGlcUA-liposomes composed of dipalmitoylphosphatidylcholine (DPPC), choleterol, and PGlcUA (40 : 40 : 20 as a molar ratio) from blood and their tissue distribution were compared with those of dipalmitoylphosphatidylglycerol (DPPG)-liposomes (DPPC/cholesterol/DPPG=40 : 40 : 20). When [³H]inulin-loaded PGlcUA-liposomes and DPPG-liposomes were intravenously injected into rats, the half-life of the PGlcUA-liposomes in the blood appeared to be 1.7-fold longer than that of DPPG-liposomes. Radioactivities present in plasma and various tissues were measured 22h after administration of these liposomes, and radioactivity remaining in the plasma was 2.5-fold greater when PGlcUA-liposomes were injected. The distribution pattern of [³H]inulin in PGlcUA-liposomes was similar to that in DPPG-liposomes. The radioactivity recovered in urine was 25% lower in rats treated with PGlcUA-liposomes than in those treated wit DPPG-liposomes. Since both PGlcUA-and DPPG-liposomes exhibited similar size distribution and ζ-potential, glucuronic acid, rather than negative charge, on the liposomal surface appears to endow liposomes with a longer circulation time in the bloodstream.

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Two polysaccharides, called glycyrrhizans UA and UB, were isolated from the root of Glycyrrhiza uralensis FISCHER. They were homogeneous on electrophoresis and gel chromatography, and showed reticuloendothelial system-potentiating activity in a carbon clearance test. Glycyrrhizan UA is composed of L-arabinose : D-galactose : L-rhamnose : D-galacturonic acid in the molar ratio of 20 : 14 : 1 : 3, and glycyrrhizan UB is composed of L-arabinose : D-galactose : D-glucose : L-rhamnose : D-galacturonic acid in the molar ratio of 12 : 10 : 1 : 10 : 20, in addition to small amounts of O-acetyl groups and peptide moiety, respectively. About 10% (glycyrrhizan UA) and 35% (glycyrrhizan UB) of the D-galacturonic acid residues exist as the methyl esters. Methylation analysis, carbon-13 nuclear magnetic resonance and periodate oxidation studies indicated their structural features.

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New fatty polynic (linoleic, linolenic, arachidonic, linoelaidic) mono esters of erythromycin A have been synthesized by using various reagents such as acyl chloride, carboxylic acid anhydride, and mixed carbonic anhydride. These different ways of activating the fatty acid allowed a regioselectivity of esterification at position 2' of the desosamine ring or position 4" of the cladinose ring of erythromycin A. The in vitro antibacterial properties of these new esters against members of the resident flora of the human skin were determined and compared with those of erythromycin A. The number and the stereochemistry of the double bonds seem to play a crucial role in the expression of thei n vitro antibacterial activity.

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The stabilities of urokinase (UK) in aqueous solution were investigated at pH 5.0-8.0 in the presence (1.0-3.0×10^-3M) and absence of sodium bisulfite (SBS) both under scattered light (1000lux) and in the dark using the fluorogenic substrate method. Increasing concentrations of SBS tended to increase the inactivation of UK. In the presence of SBS, with the increase in the pH value, UK gained stability in the pH range of 5.0-8.0. The stability of UK in the presence of SBS in the dark was larger than that under scattered light, especially at pH 5.0. Therefore, it was suggested that the difference in the residual activities of UK between under light and in the dark was due to free radicals formed during the autooxidation of bisulfite under scattered light.UK was stabilized by glucose in the presence of SBS both under scattered light and in the dark. One reason for this phenomenon was postulated to be the formation of inactive bisulfite-glucose addition compound.The degradation products of UK during storage in a solution containing SBS were investigated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. UK was revealed to be split into M.W. 36000 form and M.W. 20000 form by SBS.

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Indomethacin (IM) sustained-release suppositories were prepared by the fusion method using sugar ester and polyethylene glycol 4000 (PEG). The suppositories were evaluated by in vitro release testing, X-ray analysis and in vivo absorption testing in rabbits. X-ray analysis showed that IM was amorphous in PEG-base suppositories. In a release test, slow-release was obtained when the sugar ester content of a suppository was 60%. The IM plasma level following the administration of the suppository was well sustained in the absorption test. The main slow-release mechanism is considered to be the release of IM from the matrix composed of sugar ester and PEG, which is represented by the Higuchi equation. A good correlation between the release test and the absorption test was obtained. it is considered that the amorphous state of IM in this type of sustained-release suppository would enhance the release and absorption of IM in the rectum of the rabbit, whose rectal fluid volume is small.

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The effects of three kinds of cyclodextrins (CyDs), α-, β- and γ-CyD on biological membranes were investigated by changes in absorption of a non-absorbable drug, sulfanilic acid (SA), from the rat small intestine and rectum using an in situ perfusion technique. The absorption of SA from the intestine was slight and was not affected by the addition of CyDs. After pretreatment with a mucolytic agent, N-acetyl-L-cysteine (N-Ac), the absorption of SA was increased compared with SA alone in the presence of only β-CyD. Similar treatment with sodium deoxycholate (SDC) and sodium lauryl sulfate (SLS) to gastro-intestinal membrane showed the enhanced absorption of SA by the addition of β-CyD. The mucin layer on the surface of the gastro-intestinal membrane may play an important role in the absorption of drugs. On the other hand, enhanced absorption of SA from the rat rectum was not induced by β-CyD with or without pretreatment with N-Ac, SDC or SLS.Simultaneously, the release of neutral sugars in the perfusate after treatment with adjuvants was also observed with N-Ac, SDC and SLS. These results indicate that the mucin layer works as a barrier to the increased absorption of SA by β-CyD.

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The classification of drug binding sites on α₁-acid glycoprotein (AGP) was studied by displacement experiments using fluorescent probes. Basic drugs not only displaced basic probes strongly but also acidic probes as well. Acidic probes, on the other hand, were displaced by some acidic drugs such as phenylbutazone and sulfadimethoxine which had no effect on most of the basic probes. This contradiction suggests that the basic drugs do not completely share a binding site with the acidic drugs. The polarity of the basic drug binding site was higher than that of the acidic drug binding site. The negative charges were probably located in or near the former, different from the latter. The basic drug binding site was more sensitive to the conformational change of AGP. It seems that there are particular drug bindign sites on the AGP molecule for acidic and basic drugs. However, all the displacement data do not fully support the possibility of two independent drug binding sites. Therefore, it is rather reasonable to consider that these sites are not completely separated but are significantly overlapped and influenced by each other. Accordingly, AGP seems to have one wide and flexible drug binding area.

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A rate equation for photodegradation was derived from Lambert-Beer's law and Grotthus-Draper's law : -dc/dt=k₁(1-exp(-(k₂c+k₃(c₀-c))))k₂c/(k₂c+k₃(c₀-c))where c is the concentration of reactant, c₀ is the initial concentration of reactant, t is time, k₁ is the rate constant, and k₂ and k₃ are the absorption coefficient of reactant and its photodegradation product, respectively.In a case where the photodegradation products have no photoabsorption, k₃ assumes the value of zero in the above general equation. In a case where the photodegradation products have the same spectrum and molar absorptivity as that of the reactant, k₃ assumes the value of k₂, and hence the photodegradation is not a first-order reaction; however, the equation itself gives the pseudo-first-order reaction rate equation. In a case where the concentration of reactant is high enough, the equation approaches a zero-order reaction rate equation.The photodegradation rate of nifedipine in solutions under a germicidal lamp, near an ultraviolet fluorescent lamp and a fluorescent lamp was analyzed using the above equation. The photodegradatino rate was directly proportional to the amount of light absorbed, and fitted well with the equation. The above theoretical equation was substantiated by the photodegradation of nifedipine, and hence is expected to apply to other photosensitive drugs.

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Oxidative metabolism of cannabidiol monomethyl ether (CBDM), one of the components of marihuana, was studied in the guinea pig. Cannabielsoin monomethyl ether (CBEM) was found to be formed with hepatic microsomes by gas chromatography-mass spectrometry (GC-MS). Experiments using various modifiers of enzymatic reaction suggested that, as in the case of cannabielsoin (CBE) formation from canabidiol (CBD), CBEM was formed from CBDM by the monooxygenase system including cytochrome P450. When cannabidiol dimethyl ether (CBDD), in which phenolic hydroxyl groups of CBD are masked with methyl groups, was incubated with liver microsomes and an reduced nicotinamide adenine dinucleotide phosphate-generating system, 1S, 2R-epoxy-CBDD was identified by GC-MS. The epoxy metabolite was also found in the liver of a guinea pig pretreated with CBDD (100mg/kg, intraperitoneally) 1h before sacrifice. Rate of 1S, 2R-epoxide metabolism was slower than that of 1R, 2S-epoxy-CBDD under the conditions, as in the microsomal oxidation of CBDD described above. These results indicate that 1S, 2R-epoxides are formed from CBD, CBDM and CBDD and that the epoxides are quickly converted to elsoin-type metabolites in the cases of CBD and CBDM.

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We investigated the selectivities and structure requirements for alpha-1 and alpha-2 adrenoceptor blocking activities of yohimbine (YO) and its 12 related analogs, such as β-yohimbine (β-YO), dihydrocorynantheine (DHC) and (-)indoloquinolizidine ((-)IQ). The affinity of YO analogs to alpha-adrenoceptor was assessed by measuring their blockade of pressor responses to epinephrine in pithed rats. Among YO structure groups, the potency order was YO>DHC=β-YO>geissoschizine methylether>14β-hydroxy YO>14β-benzoyloxy YO (inactive). (-)IQ was slightly less potent than YO, but much stronger than (+)IQ. Among (±)IQ structure groups, the potency order was (±)IQ>(±)1, 12b-trans-1-hydroxy IQ»(±)1, 12b-cis-1-hydroxy IQ (imactive). (±)Borrerine was active, but (±)desmethylborrerine was inactive. The alpha-1 blocking activities of the four compounds YO, β-YO, DHC and (-)IQ, were assessed in experiments of pressor responses to methoxamine in pithed rats and contractile responses to methoxamine in the rat vas deferens. The potency order was (-)IQ>YO>DHC>β-YO. Furthermore, the alpha-2 blocking activities of the four analogs were assessed in experiments of pressor responses to clonidine and inhibition of electrically driven cardioacceleration by clonidine, in pithed rats. The potency order was YO>β-YO>(-)IQ>DHC. Based on the potency ratio between alpha-1 and alpha-2 blocking activities, DHC or YO was most selective for alpha-1 or alpha-2 subtype, respectively, among the four YO analogs. These results suggest that the A, B, C and D rings of YO analogs and their planarity are necessary for the affinity to alpha-adrenoceptors and that the predominant conformation of the carboxymethyl or hydroxy group on the E ring of YO structure determines the selectivity for alpha-1 and alpha-2 blocking activities.

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