Four possible atropisomers of meso-tetra (o-pivalamidophenyl) porphyrin, one of which is known as the picket fence porphyrin, have been prepared and their physicochemical properties examined. The visible absorption spectra of the isomers are all different, especially in DMF. The wavelength of the absorption maxima is most blue-shifted in the αααα-isomer. Phyllotype tendency, which is characterized by the relative intensity of the four bands in the visible region, was in the order αααα>ααββ≃αααβ>αβαβ. This is the same order as that of the blue shift. The order is also the same as that of the reduction potentials measured in DMF. The nuclear magnetic resonance (NMR) chemical shifts of methyl protons of the pivalamido groups are distinguishable among the four isomers even in a mixture of the isomers in chloroform or toluene. These results indicate that the conformation of the porphyrin (the distribution of the pivalamido groups between the two sides of the porphyrin plane) affects the physicochemical properties of the porphyrin. Interaction between adjacent pivalamido groups is considered to be responsible for this phenomenon.

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The amounts of concurrent adsorption of anionic species, i.e., chondroitin sulfate (Chs) and phosphate (Pi), to synthesized hydroxyapatite (HAP) were determined. The amount of adsorption of Chs decreased with increasing concentration of Pi added. On the other hand, the adsorption of Pi was not inhibited in the presence of Chs. The affinity of HAP for Pi, one of the lattice ions, is significantly greater than that for Chs. Such a specific adsorption seems favorable for crystal growth in solutions containing various kinds of solutes and/or in the body fluids. The optical density (O.D.) of the HAP suspension, as an index of the suspension stability, was measured at 550nm. The contour lines of the O.D. as a function of the concentrations of Pi and Chs showed that Chs, coexisting with Pi, exhibits a dispersing and protecting effect on the HAP suspension except at high concentrations of both Pi and Chs. It was concluded that Chs affects the formation of secondary particles of HAP (i.e., aggregation and disaggregation), but does not affect the formation of the primary particles or the crystal growth of HAP through the selective adsorption of the lattice ions.

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Three oleanene triterpenes have been isolated from the culture broth of Streptomyces strain H 1082-MY 15. Two of them were identified as known soybean sapogenols, soyasapogenols E and B. The third compound, a new triterpene, was shown to be 24-hydroxyolean-12-ene-3, 22-dione by spectroscopic analysis and chemical correlation.

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By the use of a bromomethyl-cyclohexane derivative (7), which was synthesized from d-camphor (5), as the starting compound, two kinds of chiral segments, i.e. segment A-I (3) and segment A-II (4), were synthesized. These segments are potentially versatile building blocks for construction of the left half of taxane-type diterpenoids.

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The synthesis of both enantiomers of the trans-3-acylamino-4-hydroxymethyl-2-oxo-1-sulfoazetidines 3a, b and 4a, b is described. The enantiomers of 4-hydroxymethyl-2-azetidinone, 7a and 7b, were chosen as starting materials, and the latter was synthesized from L-malic acid. For sulfonation at the N-1 position, the new amidine-N-sulfonic acid 6 was prepared and used. The preparation and antibacterial properties of the 4-acetoxymethyl derivatives 22a, b and 23a, b are described.

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An asymmetric synthesis of (1S)-(-)-trypargine (1a) was accomplished. The Pictet-Spengler condensation of (+)-N_b-benzyl-D-tryptophan methyl ester ((+)-3) with α-ketoglutaric acid, followed by methylation of the resulting monocarboxylic acid ((-)-4a), provided (1S, 3R)-(-)-methyl 2-benzyl-3-methoxycarbonyl-1, 2, 3, 4-tetrahydro-9H-pyrido [3, 4-b] indole-1-propionate ((-)-6a), which was converted into (-)-trypargine (1a). The absolute configuration of natural trypargine (1a) at the C-1 position was determined to be S.

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Methyl, ethyl, and isopropyl esters of six alkanesulfonic acids and five p-substituted benzenesulfonic acids were synthesized and their alkylating abilities were evaluated in terms of the chemoselectivity toward 4-(p-nitrobenzyl) pyridine (NBP) in phosphate buffer (pH 6.0) containing 60% acetone. The chemoselectivity constant toward NBP, S_NBP, was defined as the logarithm of the ratio of the molar fraction of an alkylating sulfonate which is consumed for alkylation of NBP versus the molar fraction of the residual alkylating agent which is hydrolyzed in the buffer medium. It was found that S_NBP was not only markedly dependent on the structure of the alkyl moiety of the molecule, but also appreciably dependent on the electronic nature of the leaving sulfonic acid moiety. The structure-chemoselectivity relationship is discussed.

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Microbiological asymmetric reduction of methyl 3-(2-furyl)-2-methyl-3-oxopropionate (5) by various yeasts was carried out. Four kinds of methyl 3-(2-furyl)-3-hydroxy-2-methyl propionates (6a-6d) could be obtained separately from the prochiral β-keto ester 5 by reduction with properly selected microorganisms. In particular, the desired syn-isomer 6a was obtained with high optical purity (>99% e.e.). Both the chemical yield and the optical purity of the reduction products (6a-6d) were significantly improved when fermentation was carried out on a large scale using a 30 1 jar fermentor or a 200 1 tank.

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The synthesis of optically active α-hydroxy β-methyl esters V by means of microbiological reduction of the corresponding α-keto β-methyl esters IV was carried out. Methyl 3-phenyl-2-oxobutyrate 3 was found to be reduced by a variety of yeasts to the α-hydroxy β-methyl esters (7b and 8a) with (2R, 3S)-and (2R, 3R)-configurations, respectively, and by carrying out screening experiments, yeasts which give products with high optical purity were actually found.

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Carbacyclin (2, R=H) was synthesized by the application of a new method for introducing the carboxylic acid side chain via dehydrative decarboxylation of the β-hydroxy carboxylic acid (19).

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Two new compounds, II and III, were isolated, together with 4-hydroxynicotinamide, from the fronds of both Arachniodes nigrospinosa and A. festina. The structures of II and III were elucidated as (E)-1-(2, 3, 4, 6-tetramethoxyphenyl) but-2-en-1-one and (E)-1-(2, 3, 4, 6-tetramethoxyphenyl) pent-2-en-1-one, respectively. Ryomenin (I) was isolated from the fronds of A. mutica.

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The synthesis of the 3-glucuronides of cortoic acids, metabolites of cortisol, is described. 20α-Cortolonic acid 3-glucuronide (11) and its 20β-epimer (12) were prepared starting from tetrahydrocortisone (1). The cortolonic acid 20-acetate methyl esters (7, 8) were the key intermediates. The 20-oxo-21-aldehyde (2) obtained from 1 by oxidation with cupric acetate was derivatized into 20-epimeric methyl cortolonates (3). When 3 was treated with tert-butyldimethylsilyl chloride and imidazole in dimethylformamide-pyridine, selective silylation of the hydroxyl group at C-3 took place. Subsequent acetylation with acetic anhydride in pyridine gave the separable 20-acetates (5, 6), which, on removal of the silyl group at C-3 with sulfuric acid, were converted into the desired intermediates. Introduction of the glucuronyl residue into the C-3 position was carried out by means of the Koenigs-Knorr reaction. The cortolic acid 3-glucuronides (21, 22) were synthesized from 5β-dihydrocortisol (13).

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Five steroidal components (PO-a (1)-PO-e (5)) were obtained from the methanolic extract or its partial hydrolysate of the fresh rhizomes of Polygonatum odoratum var. pluriflorum, and their chemical structures were characterized as (25 R and S)-spirost-5-en-3β, 14α-diol, 3-O-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranoxyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranosyl (=β-lycotetraosyl)-(25 R and S)-spirost-5-en-3β, 14α-diol, 3-O-β-lycotetraosyl-22-methoxy-(25 R and S)-furost-5-en-3β, 14α, 26-triol 26-O-β-D-glucopyranoside, 3-O-β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-1 (→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranosyl-22-methoxy-(25 R and S)-furost-5-en-3β, 14α, 26-triol 26-O-β-D-glucopyranoside and 3-O-β-lycotetraosyl yamogenin, respectively. Moreover, (25 S)-spirost-5-en-3β, 14α-diol (7) was isolated from a mixture of the (25 R) and (S) derivatives of PO-a (1) and it was designated as neoprazerigenin A.

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Imidazo [1, 2-a] indole-spirolactone 13, the principal ring system of tryptoquivalines, was successfully synthesized by a new method via oxidative double cyclization of 1-(N-alkoxy-carbonylalanyl)-3-indolepropionic acids (5) with N-bromosuccinimide, which were synthesized by acylation of benzyl 3-indolepropionate (10) with N-alkoxycarbonyl alanine p-nitrophenyl ester (12). The use of KF, 18-crown-6 and (iso-Pr)₂NEt in acetonitrile lead to high yields of benzyl 1-(N-methoxycarbonyl-α-methylalanyl)-3-indolepropionates (4). The removal of the protecting group of 13c provided 2. The mechanisms of these reactions are discussed.

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Water-soluble polysaccharides, designated as GIIa and GIIIa, were isolated together with GIa and GIb from the bark of Melia azadirachta (Meliaceae), and their anti-inflammatory effect on carrageenan-induced edema was tested. GIIa and GIIIa each gave a single peak on high-performance liquid chromatography and gel filtration. Methylation, periodate oxidation and carbon-13 nuclear magnetic resonance spectroscopic studies suggested that GIIa is composed of the following repeating unit : α-D-G1c1→4α-D-G1c1→3α-D-G1c1→3α-D-G1c6←1α-L-ArafGIIIa is [numbrical formula] a branched arabinofucoglucan containing a main chain of 1→4-linked α-D-glucopyranosyl units substituted in the 6 position with side chains of α-L-arabinofuranose and β-L-fucopyranose.

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The effects of substituents (R¹, R², and R³) on the electrochemical oxidation of the title enamines, R¹-C₆H₄-C (CN)=CH-NR²R³ (1) were investigated in acetonitrile at a glassy carbon electrode together with the oxidation of a related amine, Ph-CH (CN)-CH₂-NMe₂ (5). Cyclic voltammetry of 1 showed two or more anodic peaks depending upon the substituents. On controlled potential electrolysis at the potential of the first anodic wave, 1 with R¹=H, R²=alkyl, and R³=alkyl or H gave diphenylmethane derivatives in which two molecules of the starting enamine are coupled between the β-carbon atom and the phenyl ring para to the enamino group. Essentially the same results were obtained for 1 with R¹=m-Me or m-Cl and R²=R³=Me. A mechanism involving the dimerization of radical cations from 1 is proposed. Electrolysis of 1 with R¹=p-Cl or p-Me and R²=R³=Me, on the other hand, gave diphenylethane derivatives via coupling between the β-carbon atoms. No stable product was obtained from 1 with a phenyl group on the nitrogen atom. Results on electrolyses of the amine 5 and 1 with R¹=H and R²=R³=Me at the voltammetric peak potential of 5 argue against the possibility that an enamine is formed as an intermediate in the electrochemical dealkylation of aliphatic amines.

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A synthesis of chiral dimethylcyclopropane derivatives, useful for the synthesis of casbane, lathyrane, and ingenane-type diterpenoids, from easily available (+)-3-carene is described. The silyl enol ether (8) was derived from (-)-cis-4-caranone (7b), which was obtained from (+)-3-carene (6). Ozonolysis of 8 gave 9a and 10. The right half segment (11b) for a synthesis of crotonitenone (3) was formed from 9a in three steps. The epoxide (12) was isomerized to a mixture of the allylic alcohols (13a) and (14a), which was transformed to the ketone (20) in five steps. Methylation of 20 followed by phosphorylation and reduction gave (+)-cis-4-caranone (23) in about 40% overall yield from 12. The methylester (+)-(32b) and its enantiomer (-)-(34b) were synthesized from (+)-6. Ozonolysis of a mixture of the silyl enol ether (30) and (31) followed by methylation with diazomethane gave 32a, which was hydrolyzed to give the desired (+)-32b. The enantiomer (-)-34b was derived from 32a in five steps.

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Zinc borohydride reduction of α-methyl-β-hydroxy ketones 3 produced the erythro-2-methyl-1, 3-glycol derivatives 4 with high stereoselectivity. The selectivity was particularly high when an olefinic group was conjugated to the carbonyl group. Reduction of the same system with NaBH₄ and LiBH₄ showed poor selectivity.

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Three vitamin D analogues, (25R)-9, 10-seco-spirosta-5, 7, 10 (19)-trien-3β-ol (I), 17β (N-methyl-N-4-methylpentylamino)-9, 10-seco-androsta-5, 7, 10 (19)-trien-3β-ol (II), and (20S)-20-iso-pentylamino-9, 10-seco-pregna-5, 7, 10 (19)-trien-3β-ol (III), were prepared starting from diosgenin (IVa), 3β-hydroxy-5-androsten-17-one (Va), and 3β-hydroxy-5-pregnen-20-one (VIa), respectively, via the adducts of the corresponding 5, 7-dienes and 4-phenyl-1, 2, 4-triazoline-3, 5-dione.

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A novel ring contraction for the conversion of 2, 7-disubstituted 10H-dipyridazino [4, 5-b : 4', 5'-e] [1, 4] thiazine-1, 6-(2H, 7H)-diones (4'a-c) into the corresponding 2, 6-disubstituted 9H-dipyridazino [4, 5-b : 4', 5'-d] pyrrole-1, 5 (2H, 6H)-diones (7'a-c), through a base-induced extrusion of sulfur, is described. Heating of 4'a-c in dimethylformamide in the presence of potassium carbonate smoothly afforded 7'a-c, respectively, in good yields, although neither 2, 8-dimethyl-10H-dipyridazino [4, 5-b : 4', 5'-e] [1, 4] thiazine-1, 9 (2H, 8H)-dione (5'a), nor 3, 7-dimethyl-10H-dipyridazino [4, 5-b : 4', 5'-e] [1, 4] thiazine-4, 6 (3H, 7H)-dione (6'a) was susceptible to similar reaction conditions. The mechanism of the ring contraction, which may involve an intermediate (anion, C^-) containing a thiirane ring, is also discussed.

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2-(1-Adamantyl)-1, 3-butadiene (1) was prepared by p-toluenesulfonic acid-catalyzed dehydration of the corresponding allyl alcohol 5. The Diels-Alder reactions of 1 with a variety of dienophiles proceeded smoothly to give adamantane-substituted six-membered carbo-and heterocycles. Similarly, [4+2] cycloaddition reactions of adamantane-bearing heterodienes afforded some adamantyl-oxazines.

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N₄-Benzoyl-2'-deoxycytidine (1) was converted to its 3', 5'-di-O-acetate (2). Compound 2 was smoothly anomerized to its α-counterpart (3) by reaction with trimethylsilyl trifluoromethanesul-fonate (TMS-triflate). Saponification of 3 afforded crystalline α-2'-deoxycytidine (4). Similarly, 3', 5'-di-O-p-toluoyl-2'-deoxythymidine (5) was anomerized to the α-anomer (6), which was then deblocked to give α-2'-deoxythymidine (7). α-2'-Deoxyadenosine (8) and 9-(2-deoxy-α-D-ribofuranosyl)-6-methylthiopurine (9a) were prepared by TMS-triflate-catalyzed trans-2-deoxyribosylation from compound 2 to N₆-benzoyladenine and 6-methylthiopurine, respectively. α-5-Fluoro-2'-deoxycytidine (11a) and its β-anomer (11b) were synthesized by the reaction of the trimethylsilyl derivative of N₄-p-toluoyl-5-fluorocytosine with 1-O-acetyl-3, 5-di-O-benzoyl-2-deoxy-D-ribofuranose followed by deblocking. Among the compounds related to α-2'-deoxyribonucleosides, compound 4 and 11a showed weak growth-inhibitory activity on mouse leukemic L5178Y cells in culture. Of the nucleoside 5'-triphosphates, α-deoxy ATP had some affinity with DNA polymerase α when activated DNA was used as a template-primer. α-Deoxythymidine 5'-triphosphate (TTP) showed a remarkable inhibitory effect on DNA polymerase β when poly [rA]-oligo dT was used as template-primer.

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Six steroidal glycosides were isolated from the fresh leaves of Aspidistra elatior BLUME (Liliaceae) and the structures of these glycosides, tentatively named glycosides A (1), B (2), C (3), D (4), E (5) and F (6), were established to be neopentologenin 5-O-β-D-glucopyranoside (1), 26-O-β-D-glucopyranosyl 22-methoxy-5β-furostane-1β, 3β, 4β, 5β, 26-pentaol 5-O-β-D-glucopyranoside (2), aspidistrin (3), 26-O-β-D-glucopyranosyl 22-methoxy-5β-furostane-1β, 2β, 3β, 4β, 5β, 26-hexaol 5-O-β-D-glucopyranoside (4), methyl proto-aspidistrin (5) and magnesium 26-O-β-D-glucopyranosyl 22-methoxy-5β-furostane-1β, 3β, 4β, 5β, 26-pentahydroxy-2β-yl-sulfate monohydroxide (6), respectively. The last compound is the first sulfated steroidal glycoside to be isolated from a Liliaceous plant.

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An enzyme immunoassay (EIA) for the determination of paeoniflorin (PA), which is a principal constituent of Chinese paeony root ("Shakuyaku"in Japanese), was established by the use of 6'-hemisuccinyl (III) and 6'-hemiglutaryl PA (IV) as haptens. Compounds III and IV were coupled with β-galactosidase (β-Gal) and bovine serum albumin (BSA) by the N-hydroxysuccinimide ester method to give hemisuccinyl PA-β-Gal (IX) (labeled antigen) and hemiglutaryl PA-BSA (X) (immunogen), respectively. A 30000-fold diluted solution of anti-PA antisera elicited in rabbits by immunization with the immunogen was used for the EIA, and the separation of bound and free fractions was performed by the double antibody method using a goat antiserum to rabbit IgG. 7-β-D-Galactopyranosyloxy-4-methylcoumarin was used as the substrate for the fluorometric assay of β-Gal activity. A satisfactory standard curve for EIA of PA was obtained in the range of 1-400 ng/ml and was only slightly interfered with the addition of serum and urine to the assay mixture of EIA. The PA antiserum reacted with oxypaeoniflorin (0.31%) and albiflorin (0.22%) which are also constituents of Chinese Paeony root.

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The antithrombic activity of soyasaponins obtained from soybean was evaluated in the experimental model of disseminated intravascular coagulation (DIC) induced by infusion of endotoxin or thrombin in rats, as well as in vitro models (blood aggregation, conversion of fibrinogen to fibrin and activation of the fibrinolytic system). Total soyasaponin (TS) prevented the decrease of blood platelets and fibrinogen, and the increase of fibrin degradation products (FDP) in the endotoxin-induced DIC. TS also inhibited the formation of fibrin thrombi in the renal glomeruli in the thrombin-induced DIC. In vitro experiments, TS and soyasaponins, I, II, III, A₁ and A₂ inhibited the conversion of fibrinogen to fibrin. TS and soyasaponins I and II promoted activation of the fibrinolytic system in a plasminogen-containing fibrin plate.

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Isomerization of a chalcone having several benzyloxyl groups into a flavanone by the use of phosphoric acid in methyl cellosolve was investigated, and higher yields of flavanones were obtained with much shorter reaction times than in the conventional procedure. The reaction was applied to the synthesis of three flavanones, agestricins B, C and D, isolated from Ageratum strictum. A chalcone, agestricin A, was also prepared to confirm its structure.

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Ginsenosides and chikusetsusaponins present in the roots of Panax ginseng C. A. MEYER and rhizomes of Panax japonicus C. A. MEYER were identified as inhibitors of cyclic AMP phosphodiesterase. The structure-activity relationships of 30 saponins, 2 prosapogenins and 3 sapogenins were studied. Saponins which have a 20 (S)-protopanaxadiol or oleanolic acid moiety as the sapogenin were generally more inhibitory towards cyclic AMP phosphodiesterase than saponins with a 20 (S)-protopanaxatriol moiety as the sapogenin. The effects of various ginsenosides on corticosterone secretion and cyclic AMP phosphodiesterase activity appeared to be parallel.

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The second derivative ultraviolet (UV) spectra of aspirin and salicylic acid in a solution of powdered aspirin tablets were not interfered with by the intense and time-dependent signal backgrounds caused by excipients and antacids contained in the tablets. The promotion of aspirin hydrolysis to salicylic acid in the solution by antacids could be sufficiently suppressed by using ethanol containing 1% (w/v) of citric acid as a solvent. Three kinds of commercial aspirin tablets were assayed by second derivative UV spectrometry without any procedure for separation of the pharmaceuticals from the tablet additives. The contents of aspirin and salicylic acid could be determined with relative standard deviations of <0.5% for aspirin and <3.0% for salicylic acid.

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A radioimmunoassay method has been developed for the measurement of low concentrations of clebopride in human serum and urine samples. Antisera (clebopride-binding antibodies) were obtained from albino rabbits eight weeks after the first injection of clebopride-bovine serum albumin (BSA) conjugates. The antisera, ³H-antigen and human serum (or urine) samples or standard clebopride solutions were used in the incubation mixtures for the assay. The method has been found to be very specific, because although clebopride is extensively metabolized in man, only clebopride and its glucuronide conjugate were found to be susceptible to the antisera. The unchanged drug could be separated from the conjugate by ether-extraction prior to assay. The limit of sensitivity of this method is 0.1 ng of clebopride per ml of sample and is sufficient to measure clebopride concentrations in serum and urine of human subjects after oral administration of the therapeutic dose of 0.5 mg per man. Serum concentration profiles and some of the pharmacokinetic properties of clebopride in man have been elucidated for the first time.

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The nature of the premicellar state of sodium cholate formed at the early stages of the micelle formation process has been analyzed using pyrene as a fluorescent probe. Formation of the premicellar aggregates of cholate is dependent on a diffusion-controlled process, and stabilization of the premicellar aggregates of cholate molecules appears to require both hydrophobic and electrostatic interactions. In addition, it has been demonstrated that there is a close relationship between the efficiency of the premicellar aggregate formation and the value of the critical micelle concentration of cholate. From these observations, it is suggested that the premicellar aggregates serve as nuclei in the micelle formation process.

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The extent of binding of tritiated p-biphenylmethyl-(dl-tropyl-α-tropinium) bromide (³H-BTTB) to subcellular membranes was investigated by the centrifugal method. The following results were obtained. 1. The binding was apparently independent of enzymatic reactions. 2. The binding of BTTB to lysosomal membranes gave a linear Lineweaver-Burk plot with an apparent K_m=4.3μM and V_max=0.25 nmol·mg protein^-1·min^-1. N-Methylatropinium bromide competitively reduced the affinity of BTTB to lysosomal membranes. 3. Inhibitory effects on the binding of BTTB with lysosomal membranes were observed with choline, acetylcholine. anisotropine (quaternary ammonium compounds), quinacrine and chloroquine (tertiary amine compounds). Cetrimonium bromide (CTAB), ethidium bromide, indocyanine green, hexamethonium succinylcholine, all structurally unrelated ammonium compounds, also showed significant inhibitory effects. 4. Incubation of lysosomal membranes with increasing concentrations of indocyanine green resulted in a dose-related inhibition of the binding of ³H-BTTB. The binding of ³H-BTTB to lysosomal membranes was significantly decreased by the addition of choline at concentrations of 1 and 0.1 mM, and also by the addition of acetylcholine at a concentration of 1 mM. Methacholine and carbachol caused no change in the binding of ³H-BTTB at any concentration tested. Thus, amines and quaternary ammonium compounds competitively inhibit the binding of BTTB to lysosomal membranes by virtue of their strong affinity for lysosomes rather than because of the similarity of their structures to that of BTTB, a basic compound with affinity for lysosomes.

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A succinyl-trialanine p-nitroanilide [Suc-(Ala)₃-pNA] hydrolase which is able to hydrolyze an artificial elastase substrate, Suc-(Ala)₃-pNA, but unable to hydrolyze a naturally occurring substrate, elastin, was highly purified from hog kidney cytosol. The apparent molecular weight of the enzyme was estimated to be 65000 by gel filtration on Sephadex G-150 and 68000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the isoelectric point of the enzyme was 5.0. The enzyme is an endopeptidase which catalyzes the hydrolysis of peptides with the general structure Y-Ala (or Pro)-X (Y=peptide or N-protected amino acid ; X=amino acid moiety, peptide or amide) at the carboxyl side of alanine and proline residues. The enzyme was markedly inhibited by diisopropyl fluorophosphate and p-chloromercuribenzoate. Ethylenediaminetetraacetate and 1, 10-phenanthroline, however, were not inhibitors of the enzyme. The enzyme activity was retained on an affinity column having a proline endopeptidase [EC 3.4.21.26] inhibitor, Z-Gly-Pro, as ligand and could be eluted at 0.125M NaCl (mean value). Suc-(Ala)₃-pNA-hydrolytic activity coincided with the peak of proline endopeptidase activity as determined with a sensitive fluorogenic substrate, succinylglycyl-L-proline 4-methylcoumaryl-7-amide (Suc-Gly-Pro-MCA). The optimum pH and k_cat/K_m values (mM^-1·s^-1) were pH 7.5 and 5.4 for Suc-(Ala)₃-pNA and pH 6.8 and 24.8 for Suc-Gly-Pro-MCA, and the enzyme activity was competitively inhibited by Z-Ala-Ala and Z-Gly-Pro, as is the case with proline endopeptidase. These results suggest that Suc-(Ala)₃-pNA hydrolase in hog kidney cytosol may be identical with proline endopeptidase which was first found in human uterus as an oxytocindegrading enzyme.

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The esterification of cholesterol in sonicated dispersions with lecithin-cholesterol molar ratios of 1.5 and 3.7 by human plasma was specifically stimulated by the addition of 5×10^-4M sodium dodecyl sulfate (SDS) but not by the addition of cetyltrimethylammonium chloride (CTAC) or Tween-20. On the other hand, when residual protein fraction (d>1.210g/cm³) of human plasma instead of human plasma was used as the enzyme source, the esterification of cholesterol in the dispersion with a molar ratio of 1.5 was also stimulated at 5×10^-4M SDS while that in the dispersion with a molar ratio of 3.7 was not stimulated. However, upon addition of high density lipoprotein (HDL) (1.063<d<1.210g/cm³), the esterification of cholesterol in the dispersion with a molar ratio of 3.7 (3.9) as well as that with a ratio of 1.5 (1.1) was also stimulated. Similarly, upon addition of 1×10^-3M mercaptoethanol, the stimulatory action of SDS on the esterification of cholesterol in the dispersion with a molar ratio of 3.7 (3.9) was observed even in the absence of exogenous HDL. The stimulatory action of SDS on the acyltransferase reaction in human plasma is discussed on the basis of the above results.

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To investigate kinetically the polymorphism of pharmaceutical raw materials which has been widely recognized as one of the main factors affecting the physical stability or clinical efficacy of pharmaceutics, the quantitative evaluation of the polymorphic transition degree from powder X-ray diffraction measurements was examined. Wakelin's correlation method and the integration method, which were developed to determine the crystallinity index of crystalline materials, and the relative intensity method (I_R method), which was shown in our previous paper to be effective for evaluating the transition degree of semisynthetic fatty suppository bases, were chosen, and the validity of each method was studied both theoretically and experimentally. Physical mixtures of stable and unstable crystals of tripalmitin, glyceryl monostearate (MGSB) and Witepsol W-35 were prepared and the applicability of each method were examined. The correlation method gave precise values for all three cases whereas the integration method gave values slightly higher than the expected values. The I_R method is an easy method and gave precise results if suitable angles for the measurement were chosen, but they could not always be found, so its applicability seems to be restricted.

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Particles of AgCl were soaked in liquid NH₃ or exposed to gaseous NH₃. The ammine complexes thus formed were unstable when exposed to the atmosphere but showed characteristic X-ray patterns and differential scanning calorimetry (DSC) curves. The complex formed by soaking was found to be the triammine complex from the weight decrease after de-ammoniation and the AgCl particles recovered were seen to be porous rods on scanning electron micrographs. On the other hand, the sesquiammine complex was formed by prolonged exposure to gaseous NH₃. The AgCl particles obtained via this complex retained the external form of the original particles and were also porous when observed under an electron microscope. The specific surface areas of the particles obtained via the triammine and the sesquiammine complexes were greatly increased and reached 2.9±0.1 and 1.4±0.1 m²/g, respectively. These particles were disintegrated to some extent by applying mechanical force but the specific surface areas were decreased due to contraction of the pores resulting from the intrinsic plasticity of AgCl. In addition, AgCl was dissolved in aqueous NH₃ and the NH₃ was subsequently removed by evaporation and by freeze-drying. In the case of evaporation, AgCl was recovered as large polyhedral crystals. Since porous particles of AgCl were absent, it is clear that the crystals were directly formed from the aqueous solution without separation of solid ammine complexes. On the other hand, when the aqueous solution was freeze-dried, the recovered particles of AgCl showed porous structure and the specific surface area was found to be 3.5m²/g. Therefore, it was considered that an ammine complex-presumably the diammine complex-crystallized out during freezing of the aqueous solution. Finally, the apparent specific volumes were measured and it was found that the intraparticle void, and in some cases the external shape of the secondary porous particles, exerted a considerable influence on the packing.

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The distribution and metabolism of elcatonin ([Asu^{1, 7}]-eel calcitonin) were studied in isolated perfused rat pancreas. During the perfusion of ¹²⁵I-elcatonin, the radioactivity in the effluent rapidly attained equilibrium with the perfusate, although a considerable quantity of degradation products was observed in the effluent. The distribution space of ¹²⁵I-elcatonin was considered to be limited to the extracellular space. When unlabeled elcatonin was perfused, immunoreactive elcatonin concentration in the effluent also reached a rapid equilibrium at a lower level than that in the perfusate. These results suggest that the pancreas can degrade the entering elcatonin fairly well. The inclusion of insulin or aprotinin in the perfusate significantly suppressed elcatonin metabolism by the pancreas. Although a study of elcatonin inactivation by several proteases did not clarify the inhibitory mechanism of insulin, serine proteases were considered to be involved in the inactivation of elcatonin by the pancreas.

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The influence of administration routes of ampicillin (ABPC) on the weight of the cecum and on the cecal flora was investigated in rats. The concentration of ABPC in the cecal contents after single oral administration or multiple oral administration was higher than that after intravenous or rectal administration. However, rather high concentrations of ABPC were observed in cecal contents even after intravenous and rectal administrations. The concentrations of ABPC observed in the cecal contents after administrations by all three routes were larger than the minimum inhibitory concentrations of ABPC for all the cecal flora investigated in the present study. Enterobacteriaceae in cecal flora were increased after treatment by all routes of administration and in all dosage schedules. Staphylococci were markedly decreased except in the case of single dosage treatment. Populations of other bacteria in the cecal contents were not influenced by administration of ABPC. The route of administration did not appear to modify the influence of ABPC on the cecal flora. The weight of the cecum after oral administration of ABPC was markedly increased in comparison with that after intravenous or rectal administration.

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Intact and ground crystals of Sulfaguanidine (monohydrate) were prepared by recrystallization from aqueous solution with or without subsequent grinding. The hydrate was also prepared by sorbing H₂O vapor on the particles of anhydrous sulfaguanidine. By using these as sample materials, the dehydration curves at various temperatures were determined under dry conditions at 1 atm and in vacuo, as well as under various conditions of humidity. The applicability of various kinetic equations for solid state decomposition was investigated. It was found that chemically the same hydrate was dehydrated through different mechanisms depending on the crystal properties of the samples and the environmental conditions. In addition, changes in surface appearance of the intact and the ground crystals were observed during heating at constant temperatures. It is suggested that the differences in the dehydration mechanisms may be attributable to different modes of nuclei growth.

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A series of 5-alkylpyrazole derivatives was synthesized and evaluated for potent hypolipidemic activity in rats. Many pyrazole derivatives with an alkyl group at the 5 position of the pyrazole ring were found to possess high hypolipidemic activity. Homologation of the alkyl chain led to marked increase in activity, but introduction of other substituents at other sites on the pyrazole ring failed to enhance the activity. In addition, the replacement of the pyrazole ring with an isoxazole ring resulted in a marked decrease in activity. Among the compounds tested, 5-n-tridecylpyrazole-3-carboxylic acid (5k) exhibited the most favorable spectrum of activity and was as effective as clofibrate. This compound, 5k, showed fairly low toxicity in an acute test (LD₅₀=10.0g/kg) and hence is now undergoing further pharmacological evaluation.

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3-Demethoxyerythratidinone (1) was synthesized via the dibenzazonine base (7), which was prepared by irradiation of the phenolic compound (5) in an alkaline solution, followed by reduction of the resulting photocyclization product (6) with diborane. We investigated various oxidation reactions of 7 to yield the corresponding dienone (11). It was found that the use of active lead oxide and potassium ferricyanide as oxidants gave the dienone (11) in 65 and 60% yields, respectively. Finally, the dienone (11) was converted to 1 by hydrogenation.

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The effects of islandic acid-I (1) and related compounds on the growth of Yosida sarcoma cells and on the transfection of Bacillus phage M2-DNA have been investigated. Compound 1 inhibited the growth of Yoshida sarcoma cells at 100μg/ml, while its methyl ester (2) was 100 times more potent. Islandic acid-II methyl ester (4) and 2 produced 83 and 97% inhibition of the transfection of Bacillus phage M2-DNA at 33 and 66μg/ml, respectively. Methyl (2Z, 4E)-hexadienoate (5), having the same configuration as the side chain of 1, also inhibited the transfection of M2-DNA over a wide concentration range, but did not show cytotoxicity against Yoshida sarcoma cells in tissue culture even at 100μg/ml.

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The reactivities of the ClO₂ radical towards some organic substrates were investigated in aqueous solution by use of a rapid-mixing flow technique coupled with electron spin resonance spectroscopy. The ClO₂ radical could oxidize some aromatic amines to the corresponding cation radicals, whereas it could neither abstract hydrogen from saturated compounds such as methanol and ethanol nor add to unsaturated compounds having a double or triple bond.

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4-(p-Substituted phenyl)-4, 5-dihydro-5-oxo-thiadiazines were synthesized in fairly good yields by the reaction of phenylhydrazonomethylthioacetic acids with DCC in chloroform.

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2-Acyl-4-methyl-4H-1, 4-benzothiazines (1a, b) reacted with hydroxylamine to give dihydroisoxazolo [4, 5-b] [1, 4] benzothiazines (3a, b). However, the reaction of 1a with hydrazine did not give the dihydropyrazolo [4, 5-b] [1, 4] benzothiazine derivative corresponding to 3a, but gave its dehydro compound (6). On the other hand, in the reaction of 1b with hydrazine, formation of a pyrazole ring and opening of the thiazine ring occurred to afford a 4-(2-aminophenylthio) pyrazole derivative (7). Guanidine and acetamidine also reacted with 1a, b to give 5-[2-(N-methylamino) phenylthio] pyrimidines (10a-d).

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4-Methylcoumarin-7-yloxy tetra-N-acetyl-β-chitotetraoside (10) was synthesized from chitin in pure form by a novel procedure. After acetolysis of chitin, chitotetraose tetradecaacetate (4) was isolated by Sephadex LH-20 column chromatography. Compound 4 was chlorinated with dry hydrogen chloride to produce tridecaacetyl chitotetraosyl chloride (6). 7-Hydroxy-4-methylcoumarin sodium salt was condensed with 6 under Koenigs-Knorr reaction conditions, and the final product (10) was obtained by de-O-acetylation of condensation product (8) with sodium methoxide. 4-Methylcoumarin-7-yloxy tri-N-acetyl-β-chitotrioside (9) was also synthesized through chitotriose undecaacetate (3) isolated together with 4 in the same chromatography. Compound 10 was used in a fluorometric assay of lysozyme in comparison with 9. The high sensitivity of fluorometric determination of 7-hydroxy-4-methylcoumarin (12) made it possible to determine lysozyme concentration in the microgram range by using this substrate (10). Unlike the assay using Micrococcus lysodeikticus cell powder, lysozyme assay with this synthetic substrate (10) could be performed directly in biological materials.

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Pyrazolo [3, 4-c] [1, 5] benzothiazepines (4, 5) were transformed into quinolines (6, 7) in refluxing xylene in the presence of sodium hydride. The reaction of 6 with N, N-dimethylformamide dimethylacetal gave 1-methyl-4-oxo-3-phenyl-1, 2, 3, 4-tetrahydropyrimido [5, 4-b]-quinoline (10). The photochemical reaction of 4-anilino-2, 3-dimethyl-1-phenyl-3-pyrazolin-5-one (12) in xylene under a 100 W high pressure Hg-lamp gave 1, 2-dihydro-1-methyl-3-oxo-2-phenyl-3H-pyrazolo [4, 3-b] quinoline (3).

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Several cholestenols and cholestadienols were tested for ability to support the growth of the silkworm, Bombyx mori. 5α-Cholest-6-en-3β-ol completely fulfilled the insect sterol requirement, whereas 5α-cholest-8 (9)-en-3β-ol and (20Z)-5, 20 (22)-cholestadien-3β-ol were unable to sustain larval growth at all. The other sterols examined were partially effective as nutrients.

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Three lignans have been isolated from the roots of Stellera chamaejasme L. (Thymelaeaceae). These compounds were identified as lirioresinol-B, pinoresinol and matairesinol. The former two show piscicidal activity.

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The isopavine alkaloid (±)-reframidine (10) was synthesized from deoxypiperoin (1) via a ring opening reaction of the quaternary aziridinium salt as a key step.

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Microbiological asymmetric reduction of methyl 2-methyl-3-(2-thienyl)-3-oxopropionate (3) by various yeasts was carried out. When Kloeckera saturnus was used, the C₃-(S)-alcohols 4c and 4d were obtained, whereas other yeasts such as Lipomyces starkeyi, Saccharomyces fermentati, and Sporobolomyces salmonicolor produced the isomeric C₃-(R)-alcohols 4a and 4b. On the other hand, when Endomycopsis fibligera, Hansenula anomala, and Candida albicans were used, the C₂-(S)-reduction products 4b and 4c were obtained.

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