The equations and the mutual relations pertinent to the energetics of sequential electrooxidation and reduction steps were formulated from the points of view of the Born-Haber-type thermodynamic energy cycle and SCFMO calculations. Dependence of half-wave reduction potentials on increasing conjugation was discussed on the basis of the above equations and the symmetry of molecular orbitals. Combining the above treatments with the theory of electronic spectra the general equations have been derived for describing the mutual relation between oxidation-reduction potentials and electronic spectra. Further, the theoretical treatment was extended to the energetics of the electrooxidation and reduction process in excited states. The electron-transfer interaction between an electron donor and an electron acceptor has been considered in photoexcited states by virtue of oxidation and reduction potentials. Our treat ment provided theoretical background for the Rehm-Weller equation on the electron transfer interaction in photoexcited states. Finally, hydrophobi c and electron donor-acceptor interactions of electrogenerated active species were elucidated. The stronger inclusion of the anion radicals were observed for the dicyanobenzene anion radical-cyclodextrin complexes, being explained in terms of their dipole-induced dipole interaction. On the other hand the strong hydrogen-bonding of the electrogenerated p-quinone dianions with CH₃OH was well explained in terms of the strong n-σ type charge-transfer interaction.

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The generalization of the topological energy theory is attempt at using propagators under the Hiickel approximation. General methods to get propagators are presented for the topological reference systems under considerations. Then quantum chemical indexes of the topological reference systems are defined by analogy with those of the real systems. Some quantum chemical quantities (such as the total π electron energy, the total π electron density, the bond order and the self-atom polarizability) of a triatomic ring molecule and its topological reference system are obtained. This generalized theory enables us to rationalize the energetics and reactions of aromatic compounds.

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A possible photochemical process leading to photosensitivity due to mequitazine (MQZ) was studied in comparison with that of chlorpromazine (CPZ). Although MQZ was stable to irradiation with UVA light in ethanol or benzene, it was assumed that MQZ S-oxide was produced in aqueous solution. UVA irradiation of a skin surface lipid squalene in the presence of MQZ produced squalene hydroperoxide. Preferential involvement of Type II reaction (mediation of singlet molecular oxygen) in the photosensitized oxidation with MQZ was likely although Type I reaction (radical mechanism) was also involved in the photosensitized oxidation with CPZ. Since reaction rates of photosensitization in in vivo systems are dependent on microenvironments around photosensitizer molecules and target molecules, in vitro study on solvent dependency of the reaction rates has a critical significance.

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The adsorption behavior of surfactants on cristobalite rocks, siliceous hard shales found in Aomori Prefecture, Japan, was investigated at 25° C to clarify the surface properties of the rocks and to assess possible use as an adsorbent for the processing of waste water containing surfactants. Two kin ds of rocks tested here were found to have a comparatively large N₂ BET surface area of 56-67 m²/g with a negatively charged surface in a queous solutions. Therefore, the rocks selectively adsorbed cationic surfactants such as hexadecyltri methylammonium ion and 1dodecylpyridinium ion by electric attraction, whereas anionic surfactants such as aerosol OT were not highly adsorbed. The cationic surfact ants were thought to a dsorb on t he surface of t he rocks by t he formation of a double layer. The first layeris for med by the adsorption of the polar head of the surfactant to the surface of the rocks and the second layer is physically adsorbed on the first layer with the polar heads directed towards the solution. Anionic surfactants were adsorbed in aggregate form only at Al₂O₃ or Fe₂O₃ sites of the rocks. The amount of the adsorbed surfactant increased with the surfactant concentration of bulk solutions, following Freundlich isotherm. The ζ potential and the preference property of dispersion of the rocks with various adsorbed amounts of s urfactant, were used to predict the adsorption mechanism. It was concluded that rocks with h igh surface area and high crystallinity of silica adsorb more surfactants.

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We investigated here the HPLC-separation of alcohols including linear and cyclic monools and diols and sugar derivatives using a silica-ODS column coated with a polyhydroxy macrocyclic host compound. The host used has polar hydroxyl groups, thereby enhancing the polarity of the surface of the column. The retention times of most alcohols on such a host-coated column (R_h) are shorter than those on a host-noncoated column (R_O), as a consequence. Plots of (R_OR_h) vs R_O give a straight line for most alcohols. However, there are signficant downward deviations for such alcohols as 1-pentanol, cyclohexanol, 4-methylcyclohexanol, and hexyl α and β xylosides, in addition to cyclohexanols. This indicates that these alcohols interact with the host molecule. In particular, R_h's for 1, 2-, 1, 3-, and cis-1, 4-cyclohexanediols are slightly longer than the corresponding R_O values. These results, taken in conjunction with the stereoselectivity observed, strongly suggest that there is hydrogen-bonding interaction between these diols and the host.

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compounds were mainly produced. The N-substituted maleimides were yielded by dehydration of Nsubstituted maleamic acids. Maleic acid was formed by hydrolysis of N-substituted maleamic acid and subsequent isomerization resulted in fumaric acid. Reaction scheme which was confirmed by energy calculation was proposed. Based on these considerations, hydrolysis of N-substituted maleamic acids was prevented by coexistence of primary amine. N-Substituted maleimides were synthesized from N-substituted maleamic acids with high selectivity by employing acid and its primary amine salt mixture as catalyst.

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Reaction of S, S-diphenyl-N-tosylsulfilimine with mixed acid of conc. H₂SO₄ and conc. HNO₃ gave S, S-diphenyl-N-nitrosulfilimine in 57% yield. Pyrolysis of this N-nitrosulfilimine gave the corresponding sulfide (30%) and sulfoxide (31%). Alkaline and acidic hydrolysis gave the corresponding sulfoxide in high yields. Reactions with Grignard reagents and organolithium reagents and reductions with phenylmethanethiol, LiAlH₄, and NaBH₄ afforded the products which were considered to be formed through nucleophilic substitutions on the sulfur atom. Many of these reactions showed that Nnitrosulfilimines are more subject to the substitution than other N-substituted sulfilimines. Thermal analysis (TG-DTA/DTG, TG-Mass) of the N-nitrosulfilimine and reactions with acyl chlorides, triphenylphosphine, and oxidation with MCPBA, hydrogen peroxide and sodium hypochlorite were also examined. Results of ab initio calculation (RMP2/6-31G*) of the model compounds (H₂SNX) suggest that the S-N bond of the N-nitrosulfilimine is the longest of the N-substituted sulfilimines to consist with the above character of N-nitrosulfilimines.

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6-[(8Z, 11Z) -Pentadecatrienyl] salicylic acid (1) isolated from shell oil of indonesian cashew nut and converted to five types of derivatives, 1 to 5. Totally twenty-four compounds were synthesized using LiAlH₄ mediated reduction, oxidation with chromium trioxide, and condensation with malonic acid. To find efficient whitening agents, inhibitory activities toward tyrosinase, hyaluronidase, or inhibition of superoxide scavenger activity were examined. Both cinnamic acid derivatives 4 and cinnamyl alcohol derivatives 5 were found to be inhibited by excellent in tyrosinase activity. Derivative 5d also acted as a strong superoxide scavenger. Among the compounds tested, 1a, 4a, 1b, 4b, 1c and id were found to inhibit the hyaluronidase activity more than 90%. I Studies on the Utilization of Cashew nut Shell Oil. M.

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Absorption and fluorescence spectra were measured for species resulting from addition of acids or alkali to tetraphenylporphyrin (H₂TPP) and Zn (II) tetraphenylporphyrin (ZnTPP) in sol-gel matrices from tetramethoxysilane (TMOS). In acidic sol-gel systems of H₂TPP and ZnTPP, spectral changes were observed from the sol stage to the xerogel stage, which was ascribed to the formation of acidic dication H₄TPP²⁺. These are possibly explained by following reactions: H₂TPP + nH⁺ → H₄TPP²⁺; ZnTPP + nH⁺ → Zn²⁺ + H₄TPP²⁺. For neutral or alkaline (NaOH/TMOS = 3 x 10^-6) sol-gel systems containing H₂TPP, the absorption and emission spectra also changed from H₂TPP to H₄TPP²⁺ during the sol-gel solution like acidic systems. On the other hand, the spectra of ZnTPP didn't change without addition of acid. These results suggest that H₂TPP molecules in xerogels are protonated, but no zink ion is removed from ZnTPP in xerogel. This is explained by the acidity of silanol groups of silica pores.

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Theophylline tablets were prepared with mixed polyion powders including carboxymethylcellulose (CMC) 6-O- (2-hydroxyethyl) -N, N, N-trimethylchitosan Iodie (HETMCh) and CMC-6-O(2-hydroxyethyl) chitosan (HECh) as a carrier. The tablet was put into an artificial gastric juice and transferred into an artificial intestinal juice after a certain period incubation. The released amount of theophylline was determined using absorption spectrometry. The degree of swelling of the tablets were measured in artificial gastric juice. On a basis of the data for the absorption changes in the polyion solutions mixed in equimolar quantities of the carrier compounds, the range of pH which makes it possible to form polyion complex (PIC) was estimated. For CMCHETMCh tablets, the rate of theophylline release at a time immediately after the transfer to artificial intestinal juice was found to reach 4.7 times at its maximum as high as that for artificial gastric juice. Thus, the squeezing effects due to the theophylline release from the tablets was strongly affected depending on the mixed amount of HETMCh. The maximum squeezing effect was obtained at a mixing ratio (R= [HETMCh] / [CMC]) of 0, 5. Since the tablet containing CMCHECh can not form PIC at the pH of artificial intestinal juice, any squeezing effects were not observed with such tablets. From the present study, it was concluded that the requirements for appearance of the squeezing effects were as follows: 1) The tablet can sufficiently swell in artificial gastric juice.2) Stable PIC can be formed at the pH of artificial intestinal juice to cause a large volume shrinkage of the swelling layer of tablet.

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Cyclic fixed-bed operations under moist conditions for the recovery of carbon dioxide from flue gases have been carried out employing K₂CO₃ upported on porous materials. Moisture, usually conta ined 8 1 7% in flue gases, badly decreases the adsorption capacity in the conventional fixed-bed a dsorption technology. However, since potassium carbonate absorbs carbon dioxide in the presence o f water to form potassium hydrogencarbonate (K₂CO₃+CO₂+ H₂O ↔ 2KHCO₃), the moist conditions are rathe r necessary. Deliquecent potassium carbonate should be supported on an appropriate porous material in order to use in fixed-bed operations. A drastic decrease in surface area was observed when K₂CO₂ was supported on the hydrophilic silicagel, reflecting the blockade with K₂CO₃ in micropores, while K₂CO₃was supported on hydrophobic activated carbon without appreciable change in surface area. In th e case of pelleted a-Al₂O₃, potassium carbonate filled up the interstices of nonporous alumina powders. The XRD observations suggest hydrothermal reaction of potassium carbonate with silica g el, resulting in the decrease in CO₂ a dsorption capacity of K₂CO₃-on-SiO₂. On the other hand, reproducible CO₂-uptake was observed for K₂CO₃-on-Carbon. Entrapped CO₂ was recovered reversibly by the decom position of potassium hydrogencarbonate on flashing with steam at 150 200° C.

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Co-processing of Battle River coal and Cold Lake oil sand bitumen from Canada was carried out in the presence of Ni-Mo, Co-Mo and red-mud/sulfur catalysts under reaction conditions of 400-450° C, 10-120 min and 22-23 MPa of reaction hydrogen pressure by using a 500 ml shaking-type autoclave.
The conversion of Battle River coal during the coprocessing was 97.1 wt% (daf) at 450° C for 121min with Ni-Mo catalyst, higher than 95.7 wt% (daf) at 450° C for 120 m in with red-mud/sulfu r catalyst and anthracene oil. Cold Lake oil sand bitumen was excellent solvent to liquefy Battle River coal comparing with anthracene oil.
In the presence of Ni-Mo cataly st during the coprocessing, the hydrogen consumption was nearly the same as that with red-mud/sulfur catalyst. Ni-Mo catalyst gave higher conversion of Battle River coal in the initial stage of the reaction than red-mud/sulfur catalyst. Ni-Mo catalystalso showed good activities for removal of asphaltene and heteroatoms from Battle River coal and good hydrogen availability. Moreover, the upgrading reactions of oil products such as hydrogenation, removal of heteroatoms and lowering molecular weight proceed at 450° C.

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It was observed that in an aqueous solution (ethylenediaminetetraacetato) aquaruthenium (III), [Ru (H ₂O) (Hedta) ] reacts with salicylaldehyde oxime (H₂L) in a molar ratio of 1: 1 to give bluish purple complex (ε ₆₂₀=2100). This complex formation reaction is first-order with respect to both [Ru (H₂O)
(Hedta) ] complex and salicylaldehyde oxime concentrations. At pH 4.7, the second-order rate con stant (k_AN) was determined as k_AN= 4.15 ± 0.25 M^-l_S^-l(15° C, I =-0.1). When the acidity of the reaction solution was kept at 0.2 M with sulfuric acid, purplish-black crystals separated out rapidly.
The crystals wer e subjected to elemental analysis, pH titration and measurements of i. r. spectra and magnetic susceptibility.
These e xperimental results suggest that the crystal is a complex having a formula [Ru (H₂edta) (HL) ]· 0.5 H₂O.

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Substituent effects on the rate constants for the triethylamine-catalyzed acyl exchange reactions of N- (substituted benzoyl) -O-acetyl-o-aminophenols were investigated by ¹H-NMR spectroscopy. An analysis of the Hammett plots for the forward and backward exchange processes, in which the amide anion formation is very likely to become a rate-determining step, reveals that the reverse process has a larger reaction constant (ρ = 2.1 ± 0.1) as compared to that (ρ = 1.5 ± 0.1) for the forward process. This interesting observation was explained in terms of the idea that the greater negative charge is generated on the amide nitrogen in the transition state for the reverse process with an increase in the relative stability of acyl-exchanged isomers.

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The long-period administration of aluminum-containing phosphate binders for the treatment of hyperphosphatemia has been shown to carry the risk of aluminum accumulation associated with many bone diseases. In the previous paper, an iron chitosan complex prepared by chitosan and iron sulfate was examined as an alternative intestinal phosphate binder in vitro experiments. But it is still an essential point to enhance the phosphate binding capacity and prevent the elution of iron from iron chitosan into acidic solutions. The objective of the acetylation is to obtain more stable phosphate binder against acidic solutions.
The surface of iron chitosan was well acetylated by acetic anhydride in anhydrous ethanol. The acetylated iron chitosan gave the experimental data in vitro to be expected as a new intestinal phosphate binder, which is prevented from iron elution and insolublization of iron chitosan even in gastric juice of pH 2.

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As a rule, the S_N2 reactions of neopentyl bromide and tosylate with sodium alkoxides are extremely retarded by steric hindrance, and the yields of alkyl neopentyl ethers are poor because of side reactions such as neopentyl rearrangement, elimination, and decomposition. However, this report deals with a highly selective synthesis of alkyl and aryl neopentyl ethers. We found that the above side reactions were successfully overcome by the use of neopentyl iodide and potassium alkoxide in the mixed solvent of DMSO or DMI- alcohol (1/1-1/2) at 110-140° C. Especially, potassium benzyl oxide and triphenylmethoxide, which are stabilized by delocalization of electron, afforded the corresponding alkyl neopentyl ethers almost quantitatively under optimum conditions. On the other hand, the reactions of alkali metal aryl oxides with neopentyl iodide, tosylate, and mesylate were carried out in DMSO, DMF, and DMI. The desired aryl neopentyl ethers were readily given in substantially quantitative yields.

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