Biologically active peptides of the tachykinin and bombesin families occurring in the skin of the Australian leptodectylid frog Uperoleia rugosa were isolated in pure forms and their structures were determined. Uperolein-like peptide 1 was identified, as expected, as authentic uperolein ; uperolein-like peptide 2 was found to have the sequence Pyr-Ala-Asp-Pro-Lys-Thr-Phe-Tyr-Gly-Leu-Met-NH₂ and may be considered a Lys⁵, Thr⁶-physalaemin. Bombesin-like peptide 1, in its turn, was identified as Glu(OEt)²-litorin, and bombesin-like peptide 2 as authentic litorin. Uperolein and litorin had previously been identified in Uperoleia rugosa and Litoria aurea, respectively ; the other two peptides are new. Glu(OEt)²-litorin and Lys⁵, Thr⁶-physalaemin appear to have biological activities very similar to those of Glu(OMe)²-litorin and physalaemin (or uperolein), respectively.

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Using soya sterol (chemical composition by weight : β-sitosterol 56% ; campesterol 28% ; stigmasterol 4% ; sterol hydrocarbons and cholesterol 6% ; triterpene alcohols, keto-steroids and other steroid-like constituents 6%) and Span 85 as emulsifiers, with liquid paraffin as the dispersed phase in water, the effect of soya sterol and Span 85 on emulsion stability was evaluated in terms of the following five physicochemical parameters : (1) particle size, (2) degree of dispersion, (3) separation rate of dispersed droplets, (4) rheology of emulsion products, (5) sedimentation rate of dispersed droplets. An agitator and a homogenizer were used to produce the emulsions. The following results were obtained. (1) The particle size of emulsions prepared with soya sterol was larger than that with Span 85, and consequently, soya sterol is a less effective emulsifier than Span 85. (2) Nevertheless, soya sterol has stronger stabilizing action on emulsions than Span 85, and this effect become especially marked when emulsification was carried out with a homogenizer at a high shear rate.

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1-Phenyl-4(1H)-quinazolinones having various substituents at C-2 were synthesized and some of their reactions were examined. 1-Phenyl-2-substituted-4(1H)) quinazolinones (3) were synthesized in good yield by the reaction of 2-phenylaminobenzamide (1) with excess acid chloride under mild reaction conditions. The 2-chloroalkyl derivatives (3b-d) react with nucleophiles in a characteristic manner depending on the length of the alkyl chain. Treatment of the 2-chloromethyl derivative (3b) with nucleophiles gave 2-(substituted-methyl)-4(1H)-quinazolinones (4). Reaction of 2-chloroethyl derivative (3c) with morpholine or alcohols gave 2-(β-substituted-ethyl) derivatives (5-7) through the intermediate (8), which was identified by isolation. Allowing a chloroform solution of the 2-(γ-chloropropyl) derivative (3d) to stand afforded the 4-oxoquinazolinium salt (9a) quantitatively.

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The ¹³C-NMR spectra of 61 flavone derivatives were measured in dimethyl sulfoxide. By consideration of the chemical shifts of skeletal carbons, the parameters (α and β values) and correction factor (ο value) necessary for calculating their carbon shifts were deduced. The skeletal carbons of polysubstituted flavones and flavonols could easily be assigned by the use of these values and SCS of OMe or OH. The ¹³C-NMR spectra were confirmed to give useful information that could not be obtained from other spectral data. The data were applied for the structure elucidation of unknown polysubstituted flavones.

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Thirteen kinds of flavones, including two new flavones, were isolated from the fruit peel of Citrus reticulata BLANCO (Rutaceae) on the basis of thorough examination of the components in the chloroform extract of the peel. The structures of these flavones were confirmed by analysis of the spectral data and by structural conversion or total synthesis. β-Sitosterol, limonin, hesperidin, ferulic acid, and 5, 5'-oxydimethylene-bis(2-furaldehyde) were also isolated as components other than flavones. The multisubstituted flavones obtained were examined by gas-liquid chromatography, and may provide a good marker for chemotaxonomical studies of Citrus species.

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The reduction of 3, 4-dihydroisocoumarins (1, 3, 6, 11a, 11b, and 12b) having a hydroxyl group or acetoxyl group at the C₍₈₎-position adjacent to the lactone carbonyl group with lithium aluminum hydride gave novel products, 1, 8-dihydroxyisochromans (10a, 13, and 16a), in addition to 8-hydroxyisochromans (2, 8, and 14) and 2-(3-hydroxy-2-hydroxymethylphenyl)-ethanols (4, 9, and 15). The isochromans and 2-(2-hydroxymethylphenyl)-ethanols are known reduction products of 3, 4-dihydroisocoumarins lacking a C₍₈₎-hydroxyl group. In addition, 13 was obtained selectively in 50% yield by reduction of the magnesium chelate of 11a with lithium aluminum hydride. Similarly, 8-hydroxy-3-phenylisocoumarin (23a) and 8-acetoxy-3-phenylisocoumarin (23b) both gave 2-formyl-3-hydroxybenzyl phenyl ketone (24). Based on these results, a mechanism for the reduction of 8-hydroxy-3, 4-dihydroisocoumarins is proposed, as shown in Chart 3.

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Kinetic measurements were made to investigate the interaction of 20β-hydroxysteroid dehydrogenase and a series of steroids with C-17 and/or C-21 hydroxyl groups, and the role of the region around C-17 and C-21 on the interaction of the reacting 20-oxo group with the catalytic site of the enzyme was considered. Substitution of a hydroxyl group for hydrogen at C-21 of 17-deoxy-steroid derivatives caused a significant decrease in the apparent V_max value (to about one-sixth to one-ninth), but a slight increase in the apparent K_m value (about 1.1- to 1.8-fold). The same change at C-21 of 17-hydroxy-steroid derivatives caused little or no decrease in the apparent V_max value, but an increase in the apparent K_m (about 1.4- to 1.8-fold) occurred which was similar to that with 17-deoxy-steroid derivatives. In 21-deoxy-11-deoxy-steroid derivatives, a 17α-hydroxyl substituent had little effect on the apparent K_m value (about 0.8- to 1.1-fold) and produced a slight decrease in the apparent V_max value (to about three-quarters to two-fifths). Introduction of a 17α-hydroxyl group into 21-deoxy-11-oxo-steroid derivatives led to a significant decrease in the apparent K_m value (to about one-seventh) and a moderate decrease in the apparent V_max value (to about five-sixths to one-half). Introduction of a 17α-hydroxyl group into 21-hydroxy-steroid derivatives caused the apparent V_max value to increase by about 1.8- to 11-fold, but caused little or no decrease in the apparent K_m value. These results suggest that the hydroxyl group at the 21- or 17α-position directly restricted the conformation and the orientation of the 20-oxo group towards the catalytic site of the enzyme and influenced the hydrogen transfer stage in the catalytic process, and also that, of the substituents at the 21- and 17α-positions, the latter may preferentially affect the reaction efficiency of the 20-oxo group. The presence of an oxo group at C-11 had an indirect influence on the effects of the substituents at the 21- and 17α-positions. The optimum orientation of the 20-oxo group for the catalytic reaction may occur in 21-deoxy-17-deoxy-11-deoxy-steroid derivatives. In an ideal ternary complex, the 20-oxo group of the steroid may project towards the β-face of the steroid ring and the conformation between the 20-oxo group and α-hydrogen of C-17 is nearly staggered, while that between C-21 and the α-hydrogen of C-17, looking along the C-17 to C-20 axis, is in a skew form ; the 20-oxo group is orientated rather far from the methyl group at the β-position of C-13 and more towards the β-chain of C-16.

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An assay method for secretin in crude preparations containing unknown amounts of pancreozymin has been developed, using rats. For several hours after urethan injection there was a marked fall in the volume of pancreatic juice correlated with the decrease of protein output of rat pancreas stimulated with secretin-pancreozymin mixture, then both reached steady-state levels. In this condition, where the sensitivity to pancreozymin was reduced, the pancreatic response was linearly related to the logarithm of the dose of crude or partially purified secretin in the ranges of 0.05-0.4 and 0.5-4.0 Crick, Harper and Raper (CHR) units, respectively. Within this range, the activity of crude secretin could be determined by four- and threepoint assay procedures with an error of 10 percent or less. The validity of the assay values for the crude preparations using the three-point design was confirmed by the recovery of secretin activity as highly purified secretin (free from pancreozymin) from the crude materials.

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The inclusion complex of NH₄+ with tetranactin increases the fluxes of ions across thin lipid membranes. When NH₄+ is inserted into the ionophore of tetranactin, the conformation changes greatly ; this structural change is called an "induced fit." When the conformation change of tetranactin is induced by the approach of NH₄+, the four ether oxygens of the tetrahydrofuran rings and the four carbonyl oxygens of the ester groups function to include NH₄+ in the molecule. The ether oxygens rotate inwards to hold NH₄+ inside tetranactin, and the carbonyl oxygens rotate inwards to prevent NH₄+ from escaping. The four ether oxygens form linear hydrogen bonds with NH₄+. Although the four carbonyl oxygens approach NH₄+ at distances similar to those of the four ether oxygens, the carbonyl oxygens do not form linear hydrogen bonds with NH₄+. In order to clarify the induced fit mechanism of the ionophore, in this paper, the inclusion complex of NH₄+ with tetranactin was studied with regard to the arrangement of NH₄+ in the tetranactin molecule from a quantum-chemical point of view. Since tetranactin is too large for double zeta ab initio SCF calculations, functional groups which have large contributions to the insertion of NH₄+ were selected as a model for the tetranactin ; the model consisted of four HCHO molecules and four H₂O molecules. The model was in good accord with the actual result, and thus appears to be appropriate. Tetranactin is composed of four homonactinic acid moieties, and the interaction energy between each of them and NH₄+ is significant for the arrangement of NH₄+. The interaction energy between NH₄+ and the four ether groups was -73.2 kcal/mol, and the interaction energy between NH₄+ and the four carbonyl groups was -39.4 kcal/mol. The interaction energy between NH₄+ and the ether groups was thus about 1.9 times larger than that between NH₄+ and the ester groups. The interaction energy between NH₄+ and the eight ether and ester groups was -109.0 kcal/mol. From the results of geometry optimizations, the interaction energy between NH₄+ and CH₃OCH₃ was larger than that between NH₄+ and HCOOH by 5.8 kcal/mol due to the electrostatic interaction energy. Therefore, even though the four carbonyl groups may move to accommodate NH₄+ in tetranactin, the four ether groups of tetranactin will interact more strongly with NH₄+ than the four carbonyl groups, and NH₄+ will orient to the ether groups. Moreover, when perturbation of the ionophore by the rotation of NH₄+ is neglected, the rotational inhibition energy of NH₄+ in tetranactin was calculated to be 9.8 kcal/mol ; thus, NH₄+ is expected to orient to the four ether oxygens.

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4-Homosulfanilamide was found to react with 2-chloro-5-nitropyridine to form 5-nitro-2-(p-sulfamoylbenzylamino)pyridine, which was strongly phosphorescent in ethanol containing 0.1% (v/v) dimethyl sulfoxide. This observation was used as the basis for a procedure to determine micro amounts of 4-homosulfanilamide, and the method was also applied to the determination of 4-homosulfanilamide added to the rat plasma. A linear relationship between the phosphorescence intensity and the amine concentration was observed in the range of 4×10^-7-2×10^-5M.

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In order to search for compounds with higher activity than thiazolo [5, 4-b], imidazo-[4, 5-b] and triazolo [4, 5-b] [1, 8] naphthyridine derivatives against Ps. aeruginosa, we synthesized some heterocyclic condensed 1, 8-naphthyridine derivatives by using bifunctional 6, 7-disubstituted 1, 8-naphthyridine as a starting material. Thiadiazolo [5, 4-b] and oxazolo [5, 4-b] [1, 8] naphthyridine derivatives (3) and (5) were prepared by hydrolysis of the 6-amino-7-chloro-3-ester (1) with sodium hydroxide or sodium hydrosulfide, followed by cyclization with acetic anhydride or sodium nitrite. Pyrazolo [3, 4-b] and isothiazolo [5, 4-b] [1, 8] naphthyridine derivatives (12) and (14) were synthesized by ring cyclization of the 7-chloro-6-formyl-3-ester (10) with methyl hydrazine or ethanolic ammonia in the presence of sulfur, followed by hydrolysis. Thieno and furo [2, 3-b] [1, 8] naphthyridine derivatives (20) and (31) were prepared through a series of reaction steps, e.g. diazotization, reduction of the nitrile ester (7) or (24), ring cyclization by means of ethyl mercaptoacetate or ethyl bromomalonate, hydrolysis and decarboxylation. The compounds obtained were tested for antimicrobial activities in vitro. 8-Ethyl-5, 8-dihydro-5-oxothieno [2, 3-b] [1, 8] naphthyridine-6-carboxylic acid (20) exhibited the highest activities among these compounds against many gram-negative bacteria, including Ps. aeruginosa, and against gram-positive bacteria.

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Hydrogen peroxide oxidation of 4-(4-amino-2-methylpyrimidin-5-yl) methyl-6-(2-hydroxyethyl)-2-(2-methoxyphenyl)-4-methyl-2, 3-dihydro-4H-1, 4-thiazin-3-one (1c) gave N-[(4-amino-2-methylpyrimidin-5-yl)methyl]-N-[1-(2-oxido-1, 2-oxathiolan-3-yliden)ethyl] (2-methoxyphenyl)oxalamide (3b) and 2-oxido-1, 2-oxathiolane-3-spiro-3'-[1'-(4-amino-2-methylpyrimidin-5-yl)methyl-4'-hydroxy-2'-methylene-4'-(2-methoxyphenyl)-tetrahydropyrrol-5'-one] (6). The former product (3b) was transformed into another product (6) under oxidative reaction conditions and 6 led to the known 1-(4-amino-2-methylpyrimidin-5-yl)methyl-4-hydroxy-3-(2-hydroxyethyl)-4-(2-methoxyphenyl)-2-methyl-Δ²-pyrrolin-5-one (4) and 2-aza-2-(4-amino-2-methylpyrimidin-5-yl)methyl-4-hydroxy-4-(2-methoxyphenyl)-1-methyl-8-oxabicyclo [3.3.0] octan-3-one (5) on acid or alkali treatment. On the other hand, an oxalamide (3d) having a 2-anisyl substituent was recovered under the same reaction conditions. The same reaction with 2-aryl-4-benzyl-2, 3-dihydro-4H-1, 4-benzothiazin-3-ones (12a-c) afforded 2-aryl-4-benzyl-2-hydroxy-2, 3-dihydro-4H-1, 4-benzothiazin-3-ones (13a-c), bis-(2-aryloxalylaminophenyl)-1, 1'-disulfide (14a-b) and 2-aryl-4-benzyl-3-oxo-2, 3-dihydro-4H-1, 4-benzothiazine-1, 1-dioxide (15a-c), while 4-benzyl-2-methyl-2, 3-dihydro-4H-1, 4-benzothiazine-1, 3-dioxide (16b) was mainly obtained in the oxidation of the 2-methyl derivative (12d), which was converted into 4-benzyl-2-hydroxy-2-methyl-2, 3-dihydro-4H-1, 4-benzothiazin-3-oxide (13d) via a Pummerer-type rearrangement. The reaction mechanism is discussed.

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An analytical method for meclofenoxate and its degradation products was established by high performance liquid chromatography. The chromatographic conditions were as follows : column, μ-bondapak C₁₈ ; mobile phase, MeOH-0.1% ammonium carbonate of pH 3.1 ; flow rate, 2.0 ml/min ; spectrophotometric detection at 227 nm. The mobile phase was found to be suitable for use as an extracting solvent for pharmaceutical preparations, since it caused almost no degradation of the sample, which has been reported to be very susceptible to hydrolysis.

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The decarboxylation of various 1-substituted-3, 7-dioxabicyclo[3.3.0]octane-2, 8-diones (2b-j) was in vestigated. On treatment with potassium acetate in aqueous pyridine under reflux, all the compounds (2b-j) examined were decarboxylated in high yields to give the corresponding trans-3-hydroxymethyl-4-butanolides (3b-j). The synthesis of 10-oxa-11-deoxyprostaglandin E₂ (1a) from the compounds 3i and 3j is also described. The Moffatt oxidation of 3i and the Wittig reaction of the resulting aldehyde (6a) with dimethyl 2-oxoheptylphosphonate gave an enone (7a), which was converted into 10-oxa-11-deoxyprostaglandin E₂ methyl ester (8a) and the C₁₅-epimer (9a) by NaBH₄ reduction. Hydrolysis and subsequent relactonization of 8a gave 1a in 88% yield. A similar treatment of 9a gave 1b in 87% yield. Using a similar sequence of reactions, 1a and 1b were also prepared from the nitrile analog 3j via 8b and 9b.

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Ansamitocins and related compounds were isolated from the culture broth of Nocardia sp. 1) The total amount of the antibiotics, after extraction with ethyl acetate from the culture broth, was determined by high-performance liquid chromatography on a μ Porasil column with a solvent mixture of methylene chloride-methanol (20 : 1). 2) Each component in the mixture was quantitatively analyzed on a μ Bondapak column with 69% aqueous methanol. 3) Preparative separation of up to 5 g per cartridge column was carried out in good yield (90%) using a PrepLC/system 500 (Waters) and a column packing of Kieselgel 60 (E. Merck). The purities of the ASM obtained were above 95%.

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The reaction of dimethylsulfonium acetylcarbamoylmethylide (Ia) with quinoline 1-oxide in the presence of acetyl chloride in N, N-dimethylformamide gave 6-methyl-5-methylthio-2-[2(1H)-quinolylidene]methyl-1, 3-oxazin-4-one (IIIa) and 6-methyl-5-methylthio-2-[2(1H))quinolylidene-2-quinolyl]methyl-1, 3-oxazin-4-one (IVa). The structures of IIIa and IVa were established by chemical and spectral analysis. This is a new type of reaction of stable sulfur ylides.

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The first-order rate constants for the alkaline hydrolysis of ethyl benzoate and ethyl p-nitro- and p-aminobenzoates (benzocaine), catalyzed by CTAB, a cationic surfactant, were measured at 25°in the presence of sodium hydroxide and sodium bromide. Although the alkaline hydrolysis of esters is generally accelerated by cationic micelles, that of the three benzoates tended to be inhibited by CTAB micelles under the following conditions : (i) at high CTAB concentrations, (ii) at high concentrations of sodium hydroxide, (iii) at high concentrations of an added salt (including buffer components), (iv) at high ester concentrations, and (v) for compounds possessing a small value of the Hammett substituent constant. These effects were explained quantitatively on the basis of a theory in which the total counterion concentration is assumed to remain constant regardless of the concentrations of CTAB, sodium bromide, and sodium hydroxide, and in which the association constant for a CTAB micelle and an ester, the degree of counterion binding to CTAB micelles, the ion-exchange constant, and a relative rate constant are taken as parameters.

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The aims of the present investigation were to compare the dissolution properties of dimemorfan phosphate and dimemorfan and to control the dissolution of dimemorfan species, which are pharmacologically equivalent, by using suitable mixtures of dimemorfan phosphate and dimemorfan. The solubility of dimemorfan was studied in solutions of various pH values. It was almost constant at low pH, reached a maximum at pH 6.6, and decreased significantly with further increase of pH. Dissolution rates were determined in solutions of various pH values. Dissolution rate of dimemorfan phosphate increased gradually with increase of pH of the dissolution medium, whereas that of dimemorfan decreased. It is suggested that in the case of dimemorfan dissolution, the pH value of the saturated layer is influenced profoundly by the nature of the dimemorfan species, though the effect is small in the case of dimemorfan phosphate because of the existence of phosphate ions in the compound. Based on an analysis of the dissolution properties of dimemorfan species in solutions of different pH values, a method for controlling the release of dimemorfan species was established by the use of mixtures of dimemorfan and dimemorfan phosphate.

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Partial acid hydrolysis of Althaea-mucilage O, a representative mucous polysaccharide isolated from the roots of Althaea officinalis L., led to the isolation of five oligosaccharides. Analysis of their components, as well as reduction and methylation, and partial degradation studies showed that these oligosaccharides are O-α-(D-galactopyranosyluronic acid)-(1→2)-L-rhamnopyranose, O-β-(D-glucopyranosyluronic acid)-(1→3)-O-α-(D-galactopyranosyluronic acid)-(1→2)-L-rhamnopyranose, and the hexasaccharide, the nonasaccharide, and the dodecasaccharide composed of a repeating unit having the structure of the trisaccharide through position 4 of the D-galacturonic acid residue. The polysaccharide was also subjected to chromium trioxide oxidation, and to controlled Smith degradation. The configuration and the mode of branching were determined. The structural features of the mucilage are discussed.

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A new stereoselective synthesis of (±)-7-epideoxynupharidine (1), the most stable quinolizidine-type Nuphar alkaloid, is described. Condensation of 2-ethyl-5-methylpyridine (5) with acetonitrile, followed by ketalization, gave the ketal (13), which was hydrogenated to afford the piperidine (14). Deketalization of 14 afforded the aminoketone (15). Condensation of 15 with 3-furylaldehyde afforded four quinolizidin-2-ones (8, 16, 17, and 18) in 14, 45, 1, and 3% yields, respectively. The cis-quinolizidines (16 and 18) were isomerized to the trans-quinolizidines (8 and 17, respectively). Wolff-Kishner reduction of 8 afforded (±)-7-epideoxynupharidine (1) (45%) and (±)-1-epi-7-epideoxynupharidine (2) (15%). Similar reduction of 17 provided (±)-deoxynupharidine (3) (33%) and (±)-1-epideoxynupharidine (4) (14%).

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The effect of alloxan on cultured rat pancreatic endocrine cells was investigated by following changes in the incorporation of D-[U-¹⁴C]glucose into proteins (chloroform/methanol-insoluble fraction) and lipids (chloroform/methanol-soluble fraction). Cultured cells exposed to either alloxan or alloxan plus D-glucose anomers (16.7 mM) at 37°for 5 min were incubated in a medium containing D-[U-¹⁴C]glucose at 37°for 60 min. Alloxan at concentrations of 1.25 and 6.25 mM produced inhibitory effects on incorporation into proteins but had no effect on incorporation into lipids. Incorporation into both proteins and lipids was inhibited by 31.2 mM alloxan. The combination of 1.25 mM alloxan plus 16.7 mM D-glucose anomers synergistically reinforced the inhibitory effect of alloxan on the incorporation of labeled glucose into proteins and lipids. In addition, the action of alloxan was more effective in the presence of the β anomer than the α anomer. SDS-polyacrylamide gel electrophoresis of cells labeled with D-[U-¹⁴C]glucose indicated the involvement of cell components having molecular weights of more than 200000, 120000, 52000 and 20000. In conclusion, the present data indicate that alloxan inhibits the incorporation of D-[U-¹⁴C]glucose into proteins and lipids in cultured pancreatic endocrine cells and that the β anomer of D-glucose reinforces the action of alloxan to a greater extent than the α anomer.

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Ion pair extraction of a basic drug (trimethoprim) with sulfonphthaleins (BTB, BCG and BPB) was examined on the basis of equation (1). [numerical formula] The molar ratio, Q, of the extracted ion pair (Q=[BH⁺IH^-]_org/(C_B-[BH⁺IH^-]_org)) was represented as a function of the hydrogen ion activity ((α_H)_W) and the concentration of the sulfonphthalein monoanion ([IH^-]_W). The extraction constant, K_ex, of the equilibrium (2) was estimated from equation (1). [numerical formula] The log K_ex values of TMP-BTB were found to be 5.26, 7.08 and 8.10 in benzene-H₂O, 1, 2-dichloroethane-H₂O and CHCl₃-H₂O systems, respectively. The log K_ex values of TMP-BCG and TMP-BPB in the 1, 2-dichloroethane-H₂O system were found to be 5.89 and 4.95, respectively. The effect of pH on the ion pair extraction is discussed in terms of equation (1). The pH values suitable for the assay of TMP with BTB by means of ion pair extraction were found to be in the range of 4 to 6.

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Attempts were made to introduce an alcoholic hydroxyl group stereospecifically at the C-5 or C-6 position of 2, 3-dibenzylbutyrolactone lignans with lead tetraacetate and osmic acid as oxidizing agents. 5-Acetoxyarctigenin monoacetate (III) was obtained from arctigenin monoacetate (II), 5-acetoxyisoarctigenin monoacetate (XIII) from isoarctigenin monoacetate (XII) and 5-acetoxytrachelogenin diacetate (XXIII) from trachelogenin diacetate (XXII) by oxidation with lead tetraacetate in acetic acid. 6-Hydroxyisomethyltrachelogenin (XXXII) was obtained from 3-(3, 4-dimethoxybenzyl)-2-(3, 4-dimethoxybenzylidene) butyrolactone (XXXI) by oxidation with osmic acid. The ¹³C-NMR spectra of these oxidation products and analogs are discussed with regard to the differences of the chemical shifts resulting from changes in the substituents and the stereochemistry of the 2, 3-dibenzylbutyrolactone skeleton.

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Fumitremorgin B (2), isolated from Aspergillus fumigatus together with fumitremorgin A (1), caused severe tremors and convulsion in experimental animals. The structure of fumitremorgin B was determined from the spectral data. The stereochemistry, including the absolute configuration, was determined by X-ray analysis and comparison of the ORD of proline obtained from this compound with that of authentic L-(-)-proline.

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Photolysis of dihydroisoquinoline (2) in the presence of nitrosobenzene gives the epoxyimine (10), sodium borohydride reduction of which affords the aniline (14). Reaction of the dehydro compound (17) derived from 14 with performic acid followed by hydrolysis provides the diol (20). Hydrogenolysis of 20 over a palladium catalyst affords the corynoline analog (7). All compounds are formed under strictly stereoselective control.

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The enthalpy and entropy of the association between tris(dipivalomethanato)europium and pyridine bases or aliphatic alcohols were determined in CCl₄. The parameters of the pyridine bases are comparable with those for the reactions of pyridine base+MeI reported Brown et al. This supports the validity of our results and suggests that the two systems have analogous modes of interaction in solution. The K₁ and Δ₁ values of the pyridine base+Eu(DPM)₃ series depend on ΔH and ΔS. For aliphatic alcohols, on the other hand, there is a clear correlation between K₁ and steric factors.

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Treatment of 2', 3'-O-isopropylidene-5'-oxo-8, 5'-cycloadenosine with dimethyloxosulfonium methylide followed by hydrogenation afforded the diastereomeric pairs of 5'-methyl-5'-deoxy-8, 5'-cycloadenosine and 5'-hydroxymethyl-5'-deoxy-8, 5'-cycloadenosine. The configurations at the 5'-positions of these 8, 5'-cycloadenosines were determined by nuclear magnetic resonance (NMR) measurements. The Wittig reactions of the 5'-oxo-8, 5'-cycloadenosine with methoxymethylenetriphenylphosphorane, methylthiomethylenetriphenylphosphorane, and ethyl (dimethylsulfuranylidene) acetate afforded the corresponding 5'-substituted derivatives. The action of ethoxycarbonylmethylenetriphenylphosphorane with the 5'-oxo-8, 5'-cycloadenosine afforded the 5'-ethoxycarbonylmethylene-8, 5'-cycloadenosine, which was converted to 5'-hydroxyethyl-5'-deoxy-8, 5'-cycloadenosine by reduction with LiBH₄ followed by deacetonation. The 5'(R)- and 5'(S)-diastereomers of the 5'-hydroxyethyl derivative were separated and identified by NMR analysis. The circular dichroism (CD) spectra of the 5'-substituted-8, 5'-cycloadenosines showed that the diastereomers having the substituent at the trans-gauche position around the C₄'-C₅' bond gave strong negative CD bonds, whereas the diastereomers with the 5'-substitutent at the gauche-trans position exhibited positive bands.

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The tetradecapeptide amide venom, mastoparan X, isolated from the Japanese hornet (Vespa xanthoptera), was synthesized by the methanesulfonic acid deprotecting procedure, employing m-cresol as a cation scavenger.

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Granuliberin-R and various fragment peptides were synthesized and their histaminereleasing activities were examined. The relative potencies of granuliberin-R, H-Phe-Gly-Phe-Leu-Pro-Ile-Tyr-Arg-Arg-Pro-Ala-Ser-NH₂, as liberators of histamine from mast cells are very similar to those of substance P and bradykinin. Studies on the histamine-releasing activity of various fragment peptides of granuliberin-R showed that a 4-amino acid central sequence, -Ile-Tyr-Arg-Arg-, is the minimum requirement for the releasing action of this frog skin peptide.

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The effects of heavy metals, especially chromium, on lipid peroxidation in rat liver microsomes were studied. Lipid peroxidation was determined as thiobarbituric acidreacting materials. At lower concentrations in the range of 1-100μM, both hexavalent and trivalent chromium inhibited lipid peroxidation induced by ascorbate or NADPH in microsomes. In the presence of ascorbate, the inhibitions decreased on treatment with sulfhydryl reagents and were partly overcome by the addition of tartaric acid. It is suggested that chromium, presumably in the trivalent form, may bind with sulfhydryl groups of protein, resulting in the inhibition of lipid peroxidation. In the presence of NADPH, hexavalent chromium showed very potent inhibition. Hexavalent and trivalent chromium did not inhibit the electron-transport system in microsomes. The hexavalent form may act as a radical scavenger, since it strongly inhibited carbon tetrachloride-stimulated lipid peroxidation, could reduce 2, 2'-diphenyl-β-picrylhydrazyl to some extent in the presence of a reducing agent such as ethanol, and inhibited NADPH-induced peroxidation markedly in the presence of sulfhydryl compounds. Above 1 mM, hexavalent chromium caused lipid peroxide formation in microsomes, apparently not associated with iron, while trivalent chromium showed an inhibitory effect.

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On irradiation in 50% aqueous ethanol, the N-chloroacetyl derivatives of seven isomeric indolylethylamines gave the corresponding azocinoindole derivatives through photocyclization at the ortho and peri positions. Quantum yields for product formation with 2537 Å light showed the relative reactivity at each position of the indole ring to be in the order 3>6, 4>7, 2>5>1. In order to identify the reactive intermediary species and to establish the mechanism of the photocyclizations, frontier electron densities of several species of indole were calculated by CNDO/2 and INDO. The quantum yields for product formation from 1-substituted indole derivatives correlated fairly well (correlation coefficient r=0.82) with the singly occupied molecular orbitals (SOMO) electron densities (ED) of the 1-methylindole radical cation, but there was a better correlation (r=0.90) between the quantum yields for product formation from 1-unsubstituted compounds and the SOMO-ED of the indole-1-radical. These results show that the mechanism of the photocyclization of N-chloroacetylindolylethylamines involves both indole radical cations and indole-1-radicals as reactive intermediary species.

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Controlled potential electrolysis of triphenylphosphine in acetonitrile containing various primary alcohols and dialkyldisulfides resulted in the formation of the corresponding alkoxy and alkylthio triphenylphosphonium salts, [Ph₃P⁺-X] [ClO₄^-]. Compounds with X=OMe, OEt, OPrⁿ, SMe, SEt, and SPrⁿ were isolated. The alkoxy derivatives reacted with imidazole and thiophenol under mild conditions to give the corresponding N- and S-alkylated products quantitatively.

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Anti-2, 3-trimethylene-4-quinazolone antibody was prepared from the sera of two rabbits immunized with an antigen which was a conjugate of 6-(β-carboxypropionyl)-amino-2, 3-trimethylene-4-quinazolone and bovine serum albumin in a molar ratio of approximately 20 to 1. Specific affinity of the antibody for 2, 3-trimethylene-4-quinazolone was confirmed by comparison of the affinities for thirteen structurally related compounds.

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The structures, including stereochemistries, of two fungal metabolites, terremutin hydrate and (-)-terredionol, were shown to be [4R, 5s, 6S]-4, 5, 6-trihydroxy-2-methylcyclohexane-1, 3-dione (III) and [4R, 6R]-(-)-4, 6-dihydroxy-2-methylcyclohexane-1, 3-dione (IV) by correlating them with xylitol and [2R, 4R]-(-)-pentane-1, 2, 4, 5-tetrol, respectively.

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The chemical behavior of N^im-p-methoxybenzenesulfonylhistidine, His (MBS), was examined. This new N^im-protecting group was removable by HF or N-hydroxybenzotriazole, like the N^im-Tos group, but was more acid-stable than the Tos group with methanesulfonic acid or HBr. The N^im-MBS group was stable to treatment with trifluoroacetic acid in the presence of anisole, but was found to be cleaved smoothly by the same acid in the presence of dimethylsulfide at room temperature within an hour. The N^im-Tos group was also removable under similar conditions, but at a somewhat lower rate.

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Bromoacetaldehyde reacted with adenosine 5'-phosphate and cytidine more rapidly than chloroacetaldehyde to give 1, N⁶-ethenoadenosine 5'-phosphate and 3, N⁴-ethenocytidine, respectively. The pH-dependence of the rates of these reactions was similar to that of the chloroacetaldehyde modifications reported in the literature ; i.e. the reactions proceed smoothly in the pH range of 5 to 7. When applied to polynucleotides, bromoacetaldehyde reacted with adenine and cytosine residues located in single-stranded regions but not with those in double-stranded regions. Guanosine 5'-phosphate reacted with bromoacetaldehyde at pH 7 but only very slowly at pH 5. Bromoacetaldehyde may be useful as a more reactive subtitute for chloroacetaldehyde. Bromoacetaldehyde showed little mutagenic activity when assayed on Salmonella typhymurium TA 100.

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The synthesis of S- and N-cyclouridines, which are "anti"-fixed cyclonucleosides, is described. Bromination of S², 2'-cyclo-2-thiouridine afforded the 5-bromo derivative. Cleavage of the S², 2'-cyclo linkage of the 5-bromo derivative with methoxide resulted in the formation of S⁶, 2'-cyclo-2-O-methyluridine by intramolecular conversion of the S², 2'-linkage to an S⁶, 2'-linkage, and this was further converted to the corresponding S⁶, 2'-cyclo derivatives of uridine, isocytidine and 2-thouridine. Similarly, 2', 3'-O-isopropylidene-S², 5'-cyclo-2-thiouridine was converted to the 2', 3'-O-isopropylidene-S⁶, 5'-cyclo derivatives of uridine, isocytidine, and 2-thiouridine. 6-Methylaminouridine was cyclized by treatment with diphenyl carbonate to N⁶, 2'-cyclo-6-methylaminouridine. Cyclization with triphenylphosphine and diethyl azodicarboxylate gave the N⁶, 5'-cyclo derivative of 6-methylaminouridine.

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It was confirmed that chloramphenicol and chloramphenicol palmitate form NH₃ adducts with combining ratios of 1 : 2 (chloramphenicol : NH₃), and 1 : 2 and 1 : 1 (chloramphenicol palmitate : NH₃). The thermal and physico-chemical properties of their NH₃ adducts and the recovered chemicals were investigated by differential scanning calorimetry, infrared spectroscopy, X-ray diffractometry, and scanning electron microscopy. Elimination of NH₃ from the adducts of chloramphenicol and chloramphenicol palmitate proceeded readily at normal temperatures and pressure to yield very fine particles of the original chemicals. Further, the effect of repeating the process of sorption and desorption of NH₃ on particle size was investigated in the case of chloramphenicol palmitate by the gas adsorption method. Two or more repetitions of the process produced a significant increase in specific surface area.

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New 2 : 1 cytosine-CaCl₂ and 1 : 1 cytosine-CaCl₂ complexes were obtained from 70% ethanol and water solutions, respectively. The infrared and proton magnetic resonance spectra of the complexes were characterized in comparison with those of many cytosinemetal complexes. On the basis of these data, it is suggested that calcium coordinates with the N (3) and C (2)=O sites of cytosine in the cytosine-CaCl₂ complexes.

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C-Glycosylflavones were isolated from leaf material of Lespedeza cuneata. Isovitexin, isoorientin, vicenin-2 and lucenin-2 were identified.

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To evaluate the substituent effect, the binding of p-toluenesulfonyl-n-alkylureas to bovine serum albumin was studied by equilibrium dialysis and fluorescence titration. The binding constants obtained by fluorescence titration were nearly equal to the geometric means of the primary and secondary binding constants obtained by equilibrium dialysis. The binding constants of p-toluenesulfonyl-n-butylurea were about ten times greater than those of the other compounds tested.

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A method for the microcrystallization of amobarbital was developed. This method consists of the following procedures : (1) dissolution of amobarbital (J.P. IX) in a hot solvent such as a glycol or glycol derivative, (2) pouring this solution into cold water (3°) while stirring to precipitate microcrystals, and (3) collection and drying of the precipitated microcrystals. The crystalline properties of the pulverized crystals of amobarbital were also studied. The degree of pulverization of amobarbital by recrystallization from glycols and their derivatives decreased with increase in the number of carbon atoms in the hydrophobic chain of these solvents. Examination of pulverized amobarbital was carried out by IR, X-ray diffraction, and DSC-TG, and two kinds of polymorphs were detected.

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A protein, P-MSY, with immuno-competence promoting activity as well as antitumor activity has been isolated from bovine parotid glands. To help identify and characterize this protein, the amino-terminal and carboxylterminal amino acids were determined by Edman degradation and carboxypeptidase digestion. The amino-terminal was Ser-His- and the carboxyl-terminal was -Leu-His.

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The dimers (2a-c) of active methylene compounds were readily synthesized by heating the corresponding α-sulfinyl compounds (1a-c) in carbon tetrachloride or tetrahydrofuran in 14-90% yields.

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Nuclear magnetic resonance spectral data for a series of N-alkyl-N-(hydroxy- and oxoalkyl) nitrosamines are presented. The (Z)- and (E)-conformers of these N-nitrosamines were separated by high-pressure liquid chromatography and thin-layer chromatography.

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Reductive condensation of the amine (5) with the acid (2), followed by reduction of the carbonyl group and pyridine ring gave the cis-seco-8, 10-diazasteroid (12). Reductive cyclization of 12 with lithium aluminum hydride afforded two configurational isomers (14a, b) of 8, 10-diaza-estran. The stereochemistry of both isomers is discussed.

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cis- and trans-2, 3-Epoxycycloheptanols were prepared stereospecifically from cyclohept-2-en-1-ol (1). Oxidation of 1 with tert-butyl hydroperoxide in the presence of a molybdenum catalyst gave the cis isomer (2) in high yield. The trans isomer (3) was obtained via the bromohydrin (4). The structure of 4 is discussed.

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A sensitive high-performance liquid chromatographic technique for the quantitative analysis of the isomers of hydroxyphenylalanine has been developed. The chromatographic conditions were as follows : stainless steel column (2.1×500 mm) packed with Hitachi #3011-C resin ; mobile phase, a mixture of equal volumes of 0.025 M sodium acetate and 0.05 M acetic acid ; flow rate, 0.8 ml/min ; temperature, 45° ; detection, fluorimetric detector. This procedure was found to be suitable for the analysis of 3, 4-dihydroxyphenylalanine, p-tyrosine, m-tyrosine, o-tyrosine, and phenylalanine.

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Some cyclic derivatives of spermine and spermidine, 1, 5, 8, 12-tetraazacyclohexadecane 7, 1, 5, 9, 13-tetraazacycloheptadecane 9, and 1, 5, 9-triazacyclotridecane 11 were synthesized as part of our studies on the functions of natural polyamines and the effects of structural modification of the biological activities.

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Germacrene-D, which has sexual attractant properties similar to those of periplanone-B, has been isolated in an optically impure state from many plants, i.e., (-) and (+)-germacrene-D co-occur in different ratios in various plants. (-)-Germacrene-D isolated from Solidago altissima L. in this work was determined to have an optical purity of 18.0%. In addition, the optical rotation of optically pure germacrene-D was estimated to be 305°.

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