The interaction of 6-p-toluidinylnaphthalene-2-sulfonate (TNS) with α-cyclodextrin was investigated in a 0.1 M phosphate buffer at pH 7.4 by fluorescence spectrophotometry. Using the fact that the fluorescence intensity of TNS increases in the presence of α-cyclodextrin, the thermodynamic parameters for the inclusion complex formation were determined as follows; ΔG°=-2.21 kcal/mol at 25°C, ΔH°=-3.0 kcal/mol, ΔS°=-2.6 e.u. The driving force for the inclusion complex formation was considered to be the van der Waals-London dispersion force and hydrogen bonding between the nitrogen atom of TNS and the secondary hydroxyl groups of α-cyclodextrin.Also, from the measurements of proton nuclear magnetic resonance spectra and the model building with Corey Pauling koltum models, the most probable structure was determined.

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A practical procedure for synthesis of a new uricosuric agent, 5-chloro-7, 8-dihydro-3-phenylfuro[2, 3-g]-1, 2-benzisoxazole-7-carboxylic acid (1, AA-193) is described, which starts from 2, 5-dichlorophenol (3b) and involves 5-chloro-6-hydroxy-3-phenyl-1, 2-benzisoxazole (2) as the key intermediate. Successive treatment of 3b with benzoyl chloride-aluminum chloride (AlCl₃) and hot ethanolic sodium hydroxide gives 4-benzoyl-2, 5-dichlorophenol (8, 61%), which is oximated with hydroxylamine hydrochloride and then transformed into the benzisoxazole 2 (88%) with potassium hydroxide in N, N-dimethylformamide (DMF) (method C). The reaction of 2 with aqueous formaldehyde and dimethylamine affords the Mannich base 11a (97%), which is treated with a sulfonium ylide 12, 14 or 15 followed by heating with sodium hydroxide (NaOH) in ethanol (EtOH) to give 1 in high yield (method E).

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7-Methoxy-3-methylsulfonyl-3H-benz[d]azepine (5) and 2-deuterio-3-(methyl-d₃)-sulfonyl-3H-benz[d]azepine (14) were obtained from the reaction of the corresponding isoquinoline 2-oxides with methylsulfinylmethyl carbanion. A revised reaction mechanism is proposed on the basis of the results obtained by use of deuterated dimethyl sulfoxide-d₆.

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Chiral 5, 5-disubstituted N-acyloxymethylbarbiturates have been obtained in 40-99% optical yields by lipase-catalyzed hydrolyses of 5, 5-disubstituted N, N'-bisacyloxymethylbarbiturates in H₂O-saturated diisopropyl ether. These chiral barbiturates were readily converted into chiral drugs, mephobarbital, hexobarbital and febarbamate.

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Chiral cis-endo-2, 3-dihydroxymethyl-5-norbornene monoacetate was produced by lipase-catalyzed asymmetric transesterification, and used to synthesize an optically active thromboxane A₂ (TXA₂) antagonist.

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In connection with studies on the structure elucidation of the so-called Reisch's coumarin isolated from Toddalia asiatica, syntheses of two coumarins (4 and 5) were accomplished via the routes shown in Charts 2 and 3, respectively. Melting points and NMR data of the synthesized coumarins (4 and 5) and of related coumarins (5-methoxysuberenon, toddalenone, and Reisch's coumarin) are given in Table I, suggesting that so-called Reisch's coumarin might be 4.

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An efficient synthesis of the 1, 5-imino-3-benzazocine derivative (18) from 1, 4-diacetyl-2, 5-piperazinedione (7) and 4-methoxy-3-methylbenzaldehyde (8) is described. The tricyclic lactam (18) is shown to be a useful intermediate for preparation of a phenol (5), which has the structure of the ABC ring system of safracins and ecteinascidins. This conversion is a promising route to total synthesis of (±)-safracin A (1a).

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N-Phenylbenzimidoyl chlorides 10, 11, 12, 13, and 14 were aroylated with aromatic aldehydes 9 in the presence of a catalytic amount of 1, 3-dimethylimidazolium iodide (1) to afford N-(α-aroylbenzylidene)anilines 15, 16, 17, 18, and 19. Treatment of the resulting N-(α-aroylbenzylidene)anilines (15-19) with diluted hydrochloric acid (HCl) produced the benzils 20, 21, 22, 23, and 24 in excellent yields.

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The β-erythroidine skeleton (β-erythroidan) was synthesized as the 8-oxo derivative by two different routes. One is a four-step synthesis starting from 15, 16, 17-trimethoxy-8-oxo-cis-erythrinan (2) via ozonolytic cleavage of the aromatic ring. The other is a five-step synthesis starting from D-furano-8-oxo-cis-erythrinan (13) via oxidative cleavage of the furan ring. The two routes gave the same 14, 17-dihydro-16(15H)-oxaerythrinan-8, 15-dione (1) (8-oxo-β-erythroidan). 8-Oxo-β-erythroidan (1) was not identical with the compound previously reported by Kitahara and Matsui, suggesting that their synthesis is questionable.

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Two new lignan glycosides, named hazaleanin A (1) and hazaleanin B (2), and two new apioglucosides, named isopropyl apioglucoside (3) and 4-hydroxyguaiacol apioglucoside (4), were isolated from the bark of Fagara rhetza (Rutaceae), an Indonesian medicinal plant from Flores Island, Indonesia. The chemical structures of 1, 2, 3, and 4 have been elucidated on the basis of chemical and physicochemical evidence, including a chiral synthesis of an aglycone derivative of 1.

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Following the chemical characterization of calotroposides A (1) and B (2), five related oxypregnane-oligoglycosides named calotroposides C (3), D (4), E (5), F (6), and G (7) have benn additionally isolated from the root of Calotropis gigantea (Asclepiadaceae), an Indonesian medicinal plant. The chemical structures of the new calotroposides have been elucidated on the basis of chemical and physicochemical properties as 12-O-benzoyldeacetylmetaplexigenin 3-O-β-D-oleandropyranosyl(1→4)-β-D-oleandropyranosyl(1→4)-β-D-oleandropyranosyl(1→4)-β-D-cymaropyranosyl(1→4)-β-D-cymaropyranoside for 3, 12-O-benzoyllineolon 3-O-β-D-oleandropyranosyl(1→4)-β-D-oleandropyranosyl(1→4)-β-D-oleandropyranosyl(1→4)-β-D-cymaropyranosyl(1→4)-β-D-cymaropyranoside for 4, 12-O-benzoyldeacetylmetaplexigenin 3-O-β-D-oleandropyranosyl(1→4)-β-D-oleandropyranosyl(1→4)-β-D-cymaropyranosyl(1→4)-β-D-cymaropyranoside for 5, 12-O-benzoyllineolon 3-O-β-D-oleandropyranosyl(1→4)-β-D-oleandropyranosyl(1→4)-β-D-cymaropyranosyl(1→4)-β-D-cymaropyranoside for 6, and 12-O-benzoyllineolon 3-O-β-D-oleandropyranosyl(1→4)-β-D-cymaropyranosyl(1→4)-β-D-cymaropyranoside for 7.

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S-Alkyl dithiocarbonates (xanthates) of alkanols containing strained σ bonds underwent rearrangement to S, S-dialkyl dithiocarbonates, catalyzed by phenolic compounds. The reaction followed first-order kinetics and the rates were affected by the acidity of the phenols. The rate contants are proportional to the square of the concentration of phenol.The modified intermediate neglect of differential overlap (MINDO/3) geometry optimization indicates that S, S-dialkyl dithiocarbonate is ca. 9 kcal/mol more stable than O, S-dialkyl xanthate. The thione-thiol rearrangement and sulfide formation reactions were analyzed by MO simulations. The experimental results can be well reproduced by the MINDO/3 method rather than the modified neglect of diatomic overlap (MNDO) method. Based on these data, the reaction mechanism is discussed.

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Oxidation of the furan ring in the D-furanoerythrinan 1 with N-bromoacetamide in protic solvents gave the dioxygenated dihydrofurans 4 or 6. Acidic treatment of 4 or 6 caused two kind of reactions depending on the conditions : one is regeneration of a furan with concomitant introduction of an OR group or a double bond in the adjacent ring to give the ring C-functionalized D-furanoerythrinans 5, 8, and 9, and the other is the formation of the γ-lactones 7, 10, and 11.

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The reaction of 5-bromo-1-(2-bromoethyl)-6-bromomethyl-3-methyl-2, 4(1H, 3H)-pyrimidinedione (1) with the sodium alkoxide/2-nitropropane system and that of the dinitrate (2) of 5-bromo-1-(2-hydroxyethyl)-6-hydroxymethyl-3-methyl-2, 4(1H, 3H)-pyrimidinedione with sodium alkoxide provide convenient routes to a wide range of 3, 4-dihydro-pyrimido[6, 1-c][1, 4]oxazine derivatives (3) in excellent yields.

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Two proanthocyanidins named samarangenins A (1) and B (2) have been isolated, together with a variety of flavan-3-ols, proanthocyanidins and hydrolyzable and complex tannins, from the leaves of Syzygium samarangens (BLUME) MERR. et PERRY and S.aqueum (BURM f.) ALSTON (=Eugenia aquea BURM.). (Myrtaceae). Compounds 1 and 2 were characterized on the basis of spectroscopic and chemical evidence as novel dimeric proanthocyanidins, in which two flavanoid units are doubly linked through ether and carbon-carbon bonds.

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Four new resin glycosides, quamoclins I-IV, were isolated from the jalapin fraction of the seeds of Quamoclit pennata, and their structures have been determined on the basis of chemical and spectral data. They are the first examples of jalapins with organic acid (2S-methylbutyric acid) and fatty acid (n-decanoic or n-dodecanoic acid) groups coexisting in the molecules.

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The 5-position of 1-methyl-2-phenylthio-1H-imidazole (12a) was lithiated by lithium 2, 2, 6, 6-tetramethylpiperidide, and the produced carbanion was reacted with various electrophiles to give the corresponding 5-substituted derivatives in good yields. The reaction position was confirmed by ¹H-NMR spectroscopy and X-ray crystallography. The phenylthio group of the 5-substituted compounds could be easily removed by treatment with Raney-nickel.

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Treatment of the epoxy-acid (7) with acidic reagents produced a variety of products, hydroxy-γ- and δ-lactones (8 and 9), unsaturated δ-lactones (10, 11, and 18), and seco derivatives (15 and 17), depending on the reagents used. Alkaline hydrolysis of the hydroxy-γ-lactone (8) followed by acidification yielded an isomeric δ-lactone 21, which on further contact with acid regenerated the γ-lactone (8). The hydroxy-δ-lactones, 9 and 21, were stereoselectively dehydrated with thionyl chloride-pyridine to the unsaturated lactones, 18 and 10, respectively. Thus, successive treatments of the epoxy-acid (7) with NaOH, acidification, and dehydration of the product with thionyl chloride-pyridine gave 10 in an overall yield of 86%, and 10 was isomerized to the conjugated lactone (22) on treatment with 1, 8-diazabicyclo[5.4.0]undec-7-ene. For the above unsaturated δ-lactones, 22, 10, 11, and 18, the names α-, β-, γ-, and δ-erythroidans are proposed, respectively.

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The cyclopropane ring opening reaction of 7, 7-dimethyl-3-oxotricyclo[3.3.0.0^{2, 8}]octane-5-acetic acid (5) was examined. A regioselective C(1)-C(2) bond cleavege of 5 proceeded smoothly under acidic conditions to give a bicyclo-[3.2.1]octan-3-one derivative 7 in good yield, as a result of neighboring-group participation of the carboxyl group. The lactone 7 was then successfully transformed into the 1, 4-diketone 9, a useful intermediate for total synthesis of (±)-descarboxyquadrone (4).

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The dotriacontapeptide corresponding to the C-terminal sequence of mouse metallothionein (MT) I and related peptides which contain Cys-X-Cys-Cys (X : amino acid residue except for Cys) sequence were synthesized by the conventional solution method employing the HF deprotection method and their heavy metals (Cd²⁺, Cu²⁺ and Cu⁺)-binding properties were examined.

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A nonacosapeptide corresponding to the N-terminal sequence 1-29 (β-fragment) of mouse metallothionein I and related peptides were synthesized by the conventional solution method and their heavy metals (Cu²⁺, Cu⁺ and Cd²⁺)-binding properties were examined. The Cu<2+>- or Cu⁺-binding activities of various peptides were not greatly dependent on the peptide structure, so far as examined, as in the cases of N. crassa MT and A. bisporus MTs. On the contrary, the Cd²⁺-binding activities of these peptides were fairly structure-dependent.

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Benzoxazinorifamycin reacted with various secondary amines to yield various 5'-substituted aminobenzoxazinorifamycin derivatives. The derivatives exhibited potent acitvities against gram-positive bacteria and mycobacteria. The antimicrobial activities of these compounds against Mycobacterium tuberculosis and Mycobacterium intracellulare were superior to those of rifampicin. Some of these compounds showed good plasma levels after oral administration in rats.

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A series of acyl derivatives of 2-(3, 4-dimethoxyphenyl)ethylamine (4) were synthesized and evaluated for their effectiveness to prevent water-immersion stress-induced gastric ulceration when given intraperitoneally to rats. Among them N-[2-(3, 4-dimethoxyphenyl)ethyl]-2-phenylaminoacetamide hydrochloride (15) had significant antiulcer activity. Further modification of the four parts of 15 revealed that only the introduction of a carbamoyl group into 2- or 3-position of the phenylamino part gave compounds (49-51, 54 and 55) which retained antiulcer activity comparable to the lead compound. However, the compounds (49-51 and 54) did not exert a prophylactic effect when administered orally except for the 3-substituted bezamide derivative 55. Alkyl substitution on the nitrogen of benzamide gave 3-[[[2-(3, 4-dimethoxyphenyl)ethyl]carbamoyl]methyl]amino-N-methylbenzamide (66, DQ-2511) and the related compounds (67, 70, 74 and 77) which all had potent antiuler activities at oral doses of 50-400 mg/kg.

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Various podophyllotoxin derivatives from desoxypodophyllotoxin (DPT) were synthesized to examine the structural relationships between the biological significance (cytotoxic effect, effects on DNA topoisomerase II and tubulin polymerization) in vitro and antitumor activity in vivo (L 1210).An intact 6, 7-methylenedioxy group of DPT is necessary to inhibit tubulin polymerization and topoisomerase II. 4'-Phenolic hydroxyl group of DPT is essential to inhibit DNA topoisomerase II and the inhibitory effect on DNA topoisomerase II contributes to a high cytotoxicity.The introduction of an aminoalkoxy group at 1-position of DPT enhances the inhibitory activity against DNA topoisomerase II and cytotoxic effect, causing the inhibitory activity against tubulin polymerization to disappear. The results of antitumor test in mice bearing L 1210 on podophyllotoxin derivatives suggest the following : 1) the strong cytotoxic effect itself is not a good indication of antitumor activity in vivo as long as it is associated with inhibition of tubulin polymerization. DNA topoisomerase II inhibitory effect contributes to an antitumor activity in vivo; 2) detailed measurements of cytotoxicity and inhibition on DNA topoisomerase II and tubulin polymerization in vitro are necessary to evaluate podophyllotoxin derivatives.

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Methyl α- and β-glycosides of N-acetylneuraminic acid (Neu5Ac) and N-acetyl-3β-hydroxyneuraminic acid (Neu5Acβ3OH) (1-4) were prepared to evaluate their calcium-binding ability. (Methyl α-glucopyranosidonyl) α- and β-, and 4-methylumbelliferyl α-glycosides of Neu5Ac and Neu5Acβ3OH (5-10) were also synthesized for the comparison of chemical and enzymatic stabilities, respectively. Methyl β-glycosides of Neu5Ac and Neu5Acβ3OH, 3 and 4, respectively, showed intense calcium-binding abilities, while no such ability was observed in the corresponding α-glycosides, 1 and 2. The Neu5Aβ3OH glycosides, 6, 8, and 10, showed much stronger resistance to acidic hydrolysis and sialidase digestion than the corresponding Neu5Ac glycosides, 5, 7, and 9.

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A series of acyclic amide derivatives of N-(ω-aminoalkyl)-N-methylhomoveratrylamine was synthesized and evaluated for their bradycardic activity in isolated guinea pig right atria. Among these compounds, (E)-N-[3-[N'-2-(3, 4-dimethoxyphenyl)ethyl]-N'-methylamino]propyl]-4-[3, 4-(methylenedioxy)phenyl]-3-butenamide (35) was the most potent in vitro and was also found to show dose-dependent bradycardia without remarkable reduction of left ventricular dp/dt_max or mean aortic pressure in anesthetized dogs.

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From the roots of Polygala tenuifolia WILLD. ten new oligosaccharides, called tenuifolioses G-P, were isolated and their structures were elucidated by spectroscopic data and chemical evidance. These oligosaccharides were esterified with acetic, benzoic, p-coumaric and/or ferulic acid.

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Five flavonoid compounds, including two new isoflavanones, were isolated from the root bark of Erythrina x bidwilli. Their structures were determined to be 2, 10-di(γ, γ-dimethylallyl)-3, 9-dihydroxypterocarpan (erythrabyssin II), 6, 8-di(γ, γ-dimethylallyl)-7, 2', 4'-trihydroxyisoflavanone (bidwillon A), 8-γ, γ-dimethylallyl-2', 4'-dihydroxy-[6'', 6''-dimethylpyrano-(2'', 3'' : 7, 6)]isoflavanone (bidwillon B), 8-γ, γ-dimethylallyl-7, 4'-dihydroxyisoflavone (8-γ, γ-dimethylallyldaidzein), and 8-γ, γ-dimethylallyl-5, 2', 4'-trihydroxy-[6'', 6''-dimethylpyrano-(2'', 3'' : 7, 6)]isoflavone (auriculatin), by means of spectroscopic analysis. Some potent activities against oral microbial organisms (Fusobacterium nucleatum and Prevotella intermedia) were shown in these flavonoid compounds.

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Four new notonipetranone-type sesquiterpenoids, 7β-(3-ethyl cis-crotonoyloxy)-14-hydroxy-notonipetranone, 14-acetoxy-7β-anageloyloxy-notonipetranone, 14-acetoxy-7β-senecioyloxy-notonipetranone and tussilagolactone, were isolated together with 7β-(3-ethyl cis-crotonoyloxy)-14-hydroxy-1α-(2-methylbutyryloxy)-notonipetranone and 7β-(3-ethyl cis-crotonoyloxy)-1α-(2-methylbutyryloxy)-3, 14-dehydro-Z-notonipetranone from the flower buds of Tussilago farfara L. (Compositae). The structures of new compounds were elucidated on the basis of spectroscopic evidence.

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Eight 1-O-Alkyl-sn-glycero-3-phosphocholines (lyso platelet-activating factor; lyso PAF) were isolated from the Chinese crude drug "Jiryu, " dried body walls of the earthworm, Pheretima asiatica MICHAELSEN (Megascolecidae). They were identified by ¹H-NMR and mass spectrometry as 1-O-hexadecyl-sn-glycero-3-phosphocholine (1), 1-O-pentadecyl-sn-glycero-3-phosphocholine (2), 1-O-tetradecyl-sn-glycero-3-phosphocholine (3), 1-O-13-methyltetradecyl-sn-glycero-3-phosphocholine (4), 1-O-14-methylpentadecyl-sn-glycero-3-phosphocholine (5), 1-O-15-methylhexadecyl-sn-glycero-3-phosphocholine (6), 1-O-heptadecyl-sn-glycero-3-phosphocholine (7) and 1-O-octadecyl-sn-glycero-3-phosphocholine (8).

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[2β, 7, 7, 16β-²H₄]16α, 19-Dihydroxyandrost-4-ene-3, 17-dione (14) and [7, 7, 16β-²H₃]3β, 16α, 19-trihydroxyandrost-5-en-17-one (16), with high isotopic purity, respectively, were synthesized from unlabeled 3β-(tert-butyldimethylsiloxy)-androst-5-ene-17β-yl acetate (1). The deuterium introduction at C-7 was carried out by reductive deoxygenation of the 7-keto compound 3 with dichloroaluminum deuteride and that at C-2β and/or C-16β by controlled alkaline hydrolysis of 16-bromo-17-ketone 11 or 12 with NaOD in D₂O and pyridine. [7, 7-²H₂]3β-Hydroxyandrost-5-en-17-one (6), obtained from compound 1 by a five-step sequence, was converted to compound 14 or 16 by an eight-step or seven-step sequence, respectively. The labeled steroids 14 and 16 are useful as internal standards for gas chromatography-mass spectrometry analysis of the endogeneous levels.

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A series of dipeptidyl hydroxamic acids (H-X-Gly-NHOH : X=amino acid residues) was synthesized, and the inhibitory activity against Jack bean and Proteus mirabilis ureases [EC 3.5.1.5] was examined. A number of H-X-Gly-NHOH inhibited Jack bean urease with an I₅₀ of the order of 10^-6M and inhibited Proteus mirabilis urease with an I₅₀ of the order of 10^-5M. The inhibition against Jack bean urease was more potent than that with the corresponding aminoacyl hydroxamic acids (H-X-NHOH).

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The actions of three hexachlorobiphenyls (HCBs) 2, 3, 4, 2', 3', 4'-, 2, 3, 4, 3', 4', 5'- and 3, 4, 5, 3', 4', 5'-HCBs, on the respiration of rat liver mitochondria with succinate as the substrate were compared, and the effect of chloro-substitution sites in HCB on the respiration was examined. 2, 3, 4, 2', 3', 4'-HCB strongly inhibited both state 3 and 2, 4-dinitrophenol (DNP)-stimulated respiration with 50% inhibition dose of 52 and 54 μM for state 3 and DNP-stimulated respiration, respectively. The inhibitory action of 2, 3, 4, 3', 4', 5'-HCB on both respiration was approximately half as potent as that of 2, 3, 4, 2', 3', 4'-HCB. On the other hand, 3, 4, 5, 3', 4', 5'-HCB did not inhibit any respiration at all. These results indicate that both inside (ortho) and outside (meta or para) positions in each phenyl ring of the biphenyl molecule should be replaced with chlorines for HCB to be an effective inhibitor.Either the actual position of chloro-substituent or steric conformation caused by its substitution or both can be considered as factors affecting the inhibition. On the basis of the conformational energy, calculated by AM1 (Austin model 1) method, with increases in chlorine number in ortho position, HCB molecule became angulated. Furthermore, calculated probability of the conformation distribution for HCB indicated that the probability of nonplanarity was higher for effective HCB than for less effective HCB. These structural features suggest the significance of steric conformation as well as chloro-substituent sites in determining the inhibitory ability of HCB.The extent of inhibition of state 3 respiration by effective HCBs was similar to that of DNP-stimulated respiration, indicating that the inhibition of state 3 respiration due to effective HCBs is mainly due to the interference with the electron transport chain in succinate oxidate. The examination with 2, 3, 4, 2', 3', 4'-HCB revealed that the inhibition sites in succinate oxidate were succinate dehydrogenase and cytochrome bc₁ complex.

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Multiple forms of glucoamylases [EC 3.2.1.3] from Aspergillus saitoi and Rhizopus sp. were studied for their chitosan binding. Two forms of Aspergillus enzyme, Gluc M₁ and Gluc M₂, were bindable to chitosan, whereas three formes of Rhizopus enzyme, Gluc₁, Gluc₂, and Gluc₃, exhibited no significant binding; of these enzyme forms, Gluc M₁ and Gluc₁ are bindable to raw starch and Gluc M₁ and Gluc M₂ (less strongly) bindable to chitin. Both Gluc M₁(molecular weight (M.W.)90000) and Gluc M₂ (M.W. 70000), lacking the C-terminal portion (20000 dalton) of Gluc M₁, bound to chitosan within the narrow pH range from 6.0 to 7.0, with pH optima of 6.5-6.7, and ionic strength-dependently. The binding constants K of Gluc M₁ and Gluc M₂ to chitosan at pH 6.5 and 4°C were 1.5×10⁶ and 1.6×10⁶M^-1, respectively. Upon denaturation and modification of Gluc M₁ with 6M guanidine hydrochloride and water-soluble carbodiimide, respectively, Gluc M₁ almost completely lost the ability to bind to chitosan. A very low concentration of soluble starch (2.95×10^-4%) inhibited binding of Gluc M₁ to chitosan by 50%. Chitosan-bound Gluc M₁ showed little enzymatic activity on maltose. These results indicate that a chitosan-binding domain is not aloways identical with a chitin-binding domain or a raw starch-binding domain and that in Gluc M₁ the binding domains for raw starch, chitin and chitosan are located in this order in the direction from the C-terminal to the N-terminal; the latter two are also contained in Gluc M₂. The chitosan-binding domains of the enzymes seem to include or to reside near the active sites.

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Calcium and phospholipid-dependent protein kinase (PKC) activity was detected mainly in the cytosol of the mouse sperm. The PKC in the cytosol fraction was partially purified by ion-exchange chromatography. Using the partially purified PKC, the phosphorylation of PKC substrates was examined in vitro. The phosphorylation of the 80 kDa protein was enhanced by phorbol ester treatment in vitro as well as in vivo. The partial amino acid sequence of this protein was homologous with that of guanosine 5'-cyclic monophosphate (cGMP)-dependent protein kinase and myosin light chain kinase, both of which are related to ligand-receptor-transduction. The present data suggest that the activation of PKC and subsequent specific protein phosphorylatioin might be involved in the regulation of the zona pellucida-induced acrosome reaction.

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At least three types of vanadate-insensitive membranous ATPase were idenfied on rat liver lysosomes : bafilomycin A_-1sensitive Mg²⁺-ATPase (H⁺-ATPase), N-ethylmaleimide (NEM)-sensitive but bafilomycin A₁-insensitive Mg²⁺-ATPase (ATPase I), and NEM-insensitive Ca²⁺/Mg²⁺-ATPase (ATPase II). They showed different sensitivity to chemicals and ions with apparent molecular masses of 700-800, 500-650, and 360 kDa, respectively. Of these membranous ATPase, H⁺-ATPase seemed to constitute only one tenth of the ATPase activity on rat liver lysosomes and to be the only ATPase that exposed its active site to the cytoplasmic side of the lysosomal membranes.

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To lean whether glycation plays a role in insolubilization or in senile cataractogenesis, the reactivity of lens protein from normal and senile cataractous lenses and individual crystallin prepared from human lens with various sugars [glucose, glucose-1-phosphate (G-1-P), glucose-6-phosphate (G-6-P) and fructose], and the insolubility of those proteins were determined. The reactivity of human lens protein to glucose was increased in a dose-dependent manner, and it was demonstrated that 17.9, 18.5 and 24 kDa proteins were susceptible to glycation with sugars. The study also showed that α-, β-crystallins and high molecular weight (HMW) aggregate obtained from cataractous lens have some weak reactivity against sugars. It was demonstrated that the proteins obtained from normal lens of older age and from cataractous lenses have higher insolubilities to glucose than do normal younger ones. Measurement of glycosylated protein by affinity column chromatography revealed that cataractous lenses contained a larger amount of glycosylated protein than normal ones.These results suggest that there is an age-related increase of glycation in normal human lens protein, and that such glycation increases the amount of insolubilized protein with the effect of aging. The author also speculates that an abnormal acceleration of glycation in the human lens may induce senile cataract formation.

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DNA templates containing a modified base (O⁶-methylguanine, 8-hydroxyguanine, xanthine or hypoxanthine) which was located in nucleotide sequences corresponding to the 12th or 61st codon of a ras gene were synthesized and deoxynucleotide incorporation opposite the lesions was investigated. The templates were replicated by Taq DNA polymerase, recombinant rat DNA polymerase β and mouse DNA polymerase α-primase complex. Sequence analysis of the replicated products indicated selective incorporation of nucleotide(s) opposite a modified base, depending on the kind of base and of DNA polymerase. This system is very useful to obtain results of in vitro replication of modifled bases in ras sequences.

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The effects of 32-oxygenated lanosterol derivatives on 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity and chlesterol biosynthesis from [24, 25-³H]24, 25-dihydrolanosterol were studied. Among the derivatives, 3β-hydroxylanost-7-en-32-oic acid was the most active in depressing HMG-CoA reductase activity (IC₅₀ : 0.7 μM) and cholesterol biosynthesis (IC₅₀ : 0.4 μM) from 24, 25-dihydrolanosterol.

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The release of lidocaine from hydrogel and xerogel preparations was remarkably suppressed compared with polyethylene glycol (PEG) 2000 suppository. The release rate of lidocaine from hydrogel and xerogel increased with the increase in the amount of sodium hydroxide incorporated within the range of 3 to 7 milliequivalent (meq). After an oral administration of lidocaine HCl solution, the plasma concentration of lidocaine was considerably lower than that after intravenous administration for all time periods. The absolute bioavailability (F_oral) was 5.63%. For the Witepsol S-55 and PEG 2000 suppositories, the plasma levels of lidocaine were higher than those for the oral preparation, and C_max and area under the concentration-time curve (AUC) values significantly improved (p<0.01). The absolute bioavailabilities were 21.3 and 29.6%, respectively. On the other hand, Eudispert hv-hydrogel and xerogel preparations showed the characteristics of a sustained-release preparation, especially the xerogel preparation with 5 meq NaOH. Absolute bioavailability for hydrogel and xerogel preparations increased significantly (p<0.05) by approximately 1.7-3.4 folds compared with those of Witepsol S-55 and PEG 2000 suppositories.

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The influence of particle shape of granules or powder on tapping compaction behavior has been studied. Several kinds of samples, glass beads and glass powder, intact lactose granules and spherical lactose granules etc., where the same material was made into different shapes, were used.The diameter of the particles and the shape factor were measured. Most of the samples showed three compaction lines (lines 1-3), irrespective of the shape of the granules.The segments of the three compaction lines (k₁, k₂ and k₃) of glass powder were significantly larger than those of glass beads. The segments of line 3, (k₃), of the rounded granules were smaller than those of intact granules.Dependency on the shape of the particles was noted in the three tapping compaction lines.A case in which tapping compaction behavior could not be adapted to a straight line was reported. In this case, special particles were considered.

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Self-association of irinotecan hydrochloride (CTP-11) in an aqueous solution was studied using UV, circular dichroism (CD), ¹H-NMR and the quasi-elastic light scattering (QLS) method. The UV spectra showed a hypochromic effect in the aqueous solution. In the CD spectra, typically positive Davydov splitting was observed and the Δε value was reduced sigmoidally when the concentraion of CTP-11 was decreased. In the ¹H-NMR, the aromatic signals of higher concentration shifted to a diamagnetic direction compared with those of lower concentration. These observations suggested that CPT-11 molecules are present as monomer in the lower concentration, and the self-association with positive helicity occurs by vertical stacking more than 10 μM of concentration. Its molecules form complete aggregates at more than 2 mM of the concentration. Results of QLS which coincided in the prediction of partition coefficient experiments suggested that CPT-11 molecules formed dimer under the condition. By the regression analysis of CD spectral data, the equilibrium constant for the self-association was calculated to be 2.41×10^-4 M^-1.

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As an effective therapy for hepatocellular carcinoma, hepatic arterial chemo-embolization therapy has been widely used, and many embolizing materials have been extensively investigated. In the present study, we prepared various types of cis-diamminedichloroplatinum(II) (CDDP) albumin microspheres using chitin and chitosan, both of which have attracted considerable attention as new non-toxic biological polymer materials having favorable characteristics such as immune adjuvant activity, biological compatibility, and biodegradation.Hepatic artery of rabbit hepatic cancer models, which had transplanted VX₂ tumors, were embolized with various types of microspheres. The anti-tumor effects and tumor-targeting of the microspheres, and the effects of the microspheres administration on the hepatic tissue were investigated.As a result, anti-tumor activity of the microspheres was increased by the addition of chitin-containing or chitosan treated materials; tumor growth rates of chitin addition and chitosan treated groups were approximately 160% and 120%, respectively, and were significantly lower than that of the non-treatment groups with a rate of approximately 580%. However, complete inhibition of tumor growth might have been impossible. Anti-tomor activity was increased by the addition of chitin-containing or chitosan treated materials. Whereas the growth inhibitory effect was insufficient, in order to potentiate anti-tumor activity, higher CDDP contents and sustained release of CDDP at a high level from microsphere and so on should be essentially improved for the near future. The CDDP level in hepatic tissue following the administration of microspheres was increased by adding chitin to the microspheres or by treating the microspheres with chitosan. However, no difference was observed in the platinic concentration between the tumor portion and normal portion; thus, microspheres showed no tumor-targeting. Also, no effects of microsphere administration on functions of the liver or kidneys were observed. Based on these observations, we concluded that chitin or chitosan had an antitumor effect in VX₂ rabbit hepatic tumor models and thereby were effective as embolizing materials.

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The FDAS-SL method, which is a means of measuring the shift-length (SL, nm) of the maximum absorption wavelength of a drug by utilizing the first derivative absorption spectrum (FDAS), was used in the simultaneous spectrophotometric determination of binary mixtures. This method utilized the shift of the absorption spectrum of a drug at surfactant concentration above the critical micelle concentration. The mixed molar ratio is obtained from the shift-length, and each concentration of drug is calculated by Beer's law. The technique is applicable to binary mixed systems such as the methylparaben-propylparaben mixture which show similar absorption spectra, and gave accurate results.

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By condensation of mitomycin C (MMC) with N-succinyl-chitosan (Suc-chitosan) and carboxymethyl-chitin (CM-chitin) using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, Suc-chitosan-MMC conjugate (Sue-chitosan-MMC) and CM-chitin-MMC conjugate (CM-chitin-MMC) were prepared, respectively. The reaction conditions for 45 min at pH 5 and for 2 h at pH 5 were selected as the most appropriate for the preparations of Suc-chitosan-MMC and CM-chitin-MMC, respectively. Suc-chitosan-MMC was obtained as a water-insoluble product, while CM-chitin-MMC was partially water-soluble. When the ratio of MMC to the polymer supports changed in the conjugation reaction, the conjugates with 33% (w/w) and 23% (w/w) MMC contents were obtained as those most highly drug-loaded for Suc-chitosan-MMC and CM-chitin-MMC, respectively. At pH 7.4 at 37°C, Suc-chitosan-MMC regenerated MMC very slowly, while the release of MMC from CM-chitin-MMC was relatively fast. Each drug release followed very nearly pseudo-first order kinetics, in which the apparent drug release rate constants (k_apps) of Suc-chitosan-MMC and CM-chitin-MMC were 3.9×10^-3 and 1.1×10^-1 (h^-1), respectively.

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The effect of an ultrasound (1 MHz) on transdermal absorption of indomethacin from an ointment was studied in rats. Ultrasound energy was supplied for between 5 and 20 min at a range of intensites (0.25, 0.5, 0.75, and 1 W cm^-2), energy levels commonly used for therapeutic purposes. For evaluating skin penetration of indomethacin, the change of plasma concentration was measured. The pronounced effect of ultrasound on the transdermal absorption of indomethacin was observed at all ultrasound energy levels studied. The intensity and the time of application were found to play an important role in the transdermal phonophoretic delivery system of indomethacin; 0.75 W cm^-2 appeared to be the most effective intensity in improving the transdermal absorption of indomethacin, while the 10 min ultrasound treatment was the most effective. Although the highest penetration was observed at an intensity of 0.75 W cm^-2, 0.5 W cm^-2 was preferred because intensities of less than 0.5 W cm^-2 of ultrasound for 10 min did not result in any significant skin temperature rise nor did it have any destructive effect on rat skin. Progressively more skin damage was noted as the intensity and the time of application of ultrasound increased. When used at a proper intensity and time of application, ultrasound appears to be a safe technique for enhancing the passage of various drug molecules through human skin.

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Thermal addition reactions of 2-substituted tropones and 8, 8-dicyanoheptafulvene with benzocyclobutadiene proceeded stereoselectively to produce endo-[2π+4π]-type cyclo adducts, where the troponoid compounds acted as 4π components. Molecular orbital calculations were employed to explain the selectivity.

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The effects of inorganic and organic salts on the allylation of benzaldehyde with unactivated zinc powder and allyl bromide in acetonitrile were examined at room temperature. Although Li⁺, Na⁺, Mg²⁺, and R₄N⁺ perchlorates exerted negligible effects on the allylation, various pyridinium perchlorates except the 2, 6-lutidinium salt promoted the formation of the corresponding homoallylic alcohol from benzaldehyde. In the presence of pyridinium perchlorate, the allylation of aliphatic and aromatic aldehydes with allyl bromide and zinc smoothly proceeded to give the corresponding products in good yields. Hydroxy-, methoxy-, and halogen-substituted aromatic aldehydes were tolerated under the reaction conditions emplyed. In the case of cinnamyl aldehyde, only 1, 2-addition was observed.

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A new preparation method for a variety of 3H-indoles by 3-methylthiomethylation is described. Reactions of 1H-indoles with S, S-dimethylsuccinimidosulfonium chloride (Corey-Kim reagent) in the presence of diisopropylethylamine afforded either 3, 3-bis(methylthiomethyl)- or 3-methylthiomethyl-3H-indoles, depending upon the absence or the presence of a substituent at the C-3 position.

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The reaction of 6-amino-5-formyl (or acetyl) uracils (4) possessing a phenyl group at the 1-position with caustic alkali resulted in Dimroth rearrangement to give 6-anilino-5-formyl (or acetyl) uracils (5). This is the first example of Dimroth rearrangement observed in the uracil ring system. The presence of both the N₁-phenyl group and the 5-formyl (or acetyl) group on the uracil ring is requisite for the occurrence of the rearrangement.

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