The interaction of poly(γ-dodecyl L-glutamate) (PDOLG) and lipid at the air-water interface was investigated. The shape of the surface pressure-area (π - A) curves of monolayer of PDOLG in the α-helical conformation was characteristic of condensed films. The side chain interactions in PDOLG at the interface are hydrophobic. The π-A curve showed that the phase transition of the monolayer occurs at two points of about 16 mN⋅m^-1 and about 20 mN⋅m^-1 The temperature coefficients of the two transition pressure values are small and negative, indicating that the entropy change in the two transitions is small and that both the initial and final states are considerably ordered.
   The components in mixed films of PDOLG and either stearic acid or cholesterol were immiscible. The immiscibility seems to be due to the quite different geometrical arrangements of the two components since the molecules of PDOLG and lipids are horizontally and vertically oriented respectively relative to the interface. On the other hand, the components in mixed films of PDOLG and myristic acid were miscible. The hydrophobic portions of myristic acid in an expanded film at the air-water interface are rather in a random orientation, and hence are flexible. Therefore the hydrophobic portions may be brought into positions favorable to hydrophobic interaction with PDOLG molecule because of this flexibility. PDOLG is more miscible at the interface with the lipid to form an expanded film than with the one to form a condensed film.

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Reactivity of various alcohols on heteropolyacids was examined mainly for ether formation. In the reaction of 1-alkanols on H₃PMo₁₂O₄₀(PMo), the conversion of alcohols and the ratio of produced ether to olefin exhibited the order of C₂H₅OH<n-C₃H₇OH<n-C₄H₉OH, which was in accordance with that known for a typical solid acid catalyst (Table 1). In the temperature programmed desorption of alcohols from PMo, three peaks were obtained (Fig.1). The peak in the lowest temperature corresponded to the desorption of physisorbed alcohols and the one in the middle to the desorption of olefins which is produced from chemisorbed alcohols (Table 2). Between these two temperature ranges, a very small amount of ether was produced as detected by means of mass spectroscopy. On the basis of the results mentioned above and the function known of heteropoly compounds to absorb alcohols into their bulk, it was considered that the ether is produced from the chemisorbed alcohols and the weakly physisorbed ones. The heteropoly compounds exhibited high activities for methyl t-butyl ether (MTBE) forma tion from CH₃OH and t-C₄H₉OH (TBA), compared with other solid acids like SiO₂-Al₂O₃(Fig.3). The space time yield of MTBE showed abnormal dependence on the partial pressure of CH₃OH (Fig.4). A similar relationship was also observed between the amount of sorbed CH3OH and the partial pressure of CH₃OH (Fig.5). This observations indicate that the active species derived from the chemisorbed TBA react with the weakly physisorbed CH8OH to form MTBE. The heteropoly compounds are superior to other solid acids in regard to MTBE formation because of their high ability to activate TBA and to absorb large amounts of CH3OH.

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Addition of nitrobenzene to the supporting electrolyte, containing 0.1mol/dm³ sulfric acid, increased the photoreduction current at the p-type gallium arsenide electrode. The product of the photoelectrochemical reduction was four electron reduced phenylhydroxylamine. Addition of nitrosobenzene, which is considered as a intermediate species of the reduction of nitrobenzene, also caused an increase in the photoreduction current. p-Nitrophenol and p-nitrosophenol showed the same results. From these results, it was indicated that the photoelectrochemical reduction of aromatic nitro compounds took placed in the photo-current doubling process. A tentative mechanism for the current doubling behaviour on the p-GaAs photoelectrode was proposed.

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The effect of kind of anion in water on the formation of hydrous lead(II) oxide has been investigated in detail using X-ray diffractometry, scanning electron microscopy and chemical analysis on the oxygen pressurized wet milling method, i. e., on the oxidation process of spherical granules (3-5 mm in diameter) of metallic lead with pressurized oxygen (2.0-7.2kg⋅cm^-2) in the presence of water in the rotary mill. The oxidation behavior of the surface of metallic lead plate (10 x20 x 0.7 mm) with dissolved oxygen in water has also been observed. It was found that white hydrous lead(II) oxide (3 PbO⋅H₂O, tetragonal) was formed according to the ability of complex formation of the adding anions with lead(II) ion and also to the concentration of the anions, as typically shown in Fig.6, whereas yellow massicot (orthorhombic)or the mixture of massicot with red litharge (tetragonal) was formed in the absence of any anions at low or high temperature, respectively. Namely, the addition of small amount of anions having high ability of complex formation with lead(II) ion such as citrate and EDTA ions (1 x10^-4-2.4 x 10^-2 mol⋅dm^-3) facilitated the selective formation of 3 PbO. H₂O over a temperature range 3 to 60°C instead of the anhydrous lead(II) oxides. In the presence of acetate ion, 3 PbO⋅H₂O was formed together with massicot. Chloride and nitrate ions, which have no longer sufficient ability of complex formation with lead(II) ion, did not affect the crystal form of the product.

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Nickel in a dilute aqueous solution can be recovered as a mixed sulfide precipitate of Ni₃S₂-NiS-Cu₂S by bubbling H₂S gas in the presence of copper powder. The optimum condition for leaching of nickel and copper from the mixed sulfides has been investigated in the present paper. A mixed sulfide composed of Ni₃S₂ 47.7 wt%, NiS 7.5 wt% and CU₂S 44.0 wt% was prepared at 363 K, and effect of leaching variables on the extraction of nickel and copper and the ratio of sulfate ion in the oxidized sulfur were studied. Both nickel and copper were extracted at their yield of 95% or more under following optimum conditions: temp.343 K, PO2; 1.00, MPa, [HCL]/2 [Ni+Cu] molar ratio; 1.377, leaching time; 2 h, sufficient stirring speed; 1000 rpm in the experiment. An induction period on the leaching of copper was obserbed both at lower stirring speeds and at lower oxygen partial pressures because of the evolution of H₂S gas by the acid decomposition of Ni₃S₂. When both oxygen partial pressure and stirring speed were sufficiently high, plots of first order rate reaction were obtained for the leaching of nickel by the oxidation of NiS, while the leaching of copper obeyed second order reaction. Most of the sulfur in the sulfide was oxidized to elemental sulfur and 5-30%of the sulfur to sulfate ion. The ratio of sulfate ion to elemental sulfur increased with the increase of oxygen partial pressure and the decrease of the temperature. In the presence of iron(II) ion, the formation of sulfate was suppressed. When molar ratio of [HCL]/2 [Ni+Cu]was below unity, nickel was selectively extracted and copper was precipitated as the basic salt.

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Single crystals of single-phase compounds, VB, V₃B₄ and VB₂ are prepared by using the molten Al flux in an argon atmosphere. The optimum mixing atomic ratios (B/V and Al/V), reaction temperatures and reaction time are as follows: B/V=0.7, Al/V=28.3-37.7, 1500°C, 10 h (VB); B/V=1.2, Al/V=47.2, 1500°C, 10 h (V₃B₄); B/V=2.2, Al/V=28.3-47.2, 1500°C, 50 h (VB2). VB single crystals of pillar-shape grown to ‹100› or ‹001› direction, V₃B₄ single crystals of thin plate-like, thick trapezoidal shape of well-developed (010) face, and of pillar-shape grown to ‹100› or ‹001› direction, and VB₂ single crystals of hexagonalpolyhedral shape were obtained.

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Ionic type chromium(III) complexes [Cr(HL)₃]Cl₃. n H₂O (n=2 or 3) of thiosemicarbazide (Htsc) and 4-substituted thiosemicarbazides (4-methyl-(Hmtsc), 4-ethyl-(Hetsc), 4-allyl(Hatsc), and 4-phenyl-(Hptsc)) were isolated, and also noncharged complexes [Cr(L)₃] were isolated only when the ligand is Htsc or Hptsc. The electronic spectra of these complexes were similar no change in the ligand field strength due to the difference of the substituted groups was observed. Thermal analysis of both type complexes showed that the decomposition temperature of the ionic type complexes was higher than that of the corresponding noncharged complexes, suggesting that the former was more stable than the latter. An intensively endothermic phenomenon was observed at the first mass decrease of the ionic type complexes by the thermal decomposition, but was not observed for the noncharged complexes. The analytical studies on the infrared spectra of both thermal decomposition products revealed that the ligand was split off from metal with the endothermic effect in the case of the ionic type complexes, but the ligand for the noncharged complexes, was thermally decomposed without being split off from metal.

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Palladium (II) reacts with 5-methylfurfural 2-benzothiazolylhydrazone (MFBH or HR) to form a stable 1: 2 (metal: ligand) complex (λ_max=423 nm, ε=2.8 x 10⁴dm³⋅mol^-1⋅cm^-1 in a micellar solution of Triton X-100, and λ_max=425 nm, ε=2.9 x 104 dm³⋅mol-1⋅cm^-1 in benzene). The complex is extracted into benzene from acid medium and gives a constant absorbance when extracted from a sulfuric acid of 0.05-0.4 mol⋅dm^-3. Beer's law was confirmed over a range of 4-35 μg Pd2+/10 cm³ benzene and the sensitivity which gave an absorbance of 0.001 was 0.0037, μg⋅cm^-2. On these basis, a practical method for the deter mination of traces of palladium has been developed. The proposed procedure was applied to the determination of palladium in dental alloys with satisfactory results. In the recommended conditions, the rate of the reaction was of first-order with respect to each concentration of palladium(II) and MFBH, and of zero-and inverse first-order with respect to the hydrogen ion concentration. From these results, it was assumed that the ratedetermining step is the 1: 1 chelate formation between palladium(II) and MFBH in the aqueous phase, and that the reaction proceeds through the three competitive reactions: ( i )pd2+ R → P, (ii) P2a+ H R → P and (iii) PdOH+ HR → P. The rate constant for the reaction (ii), which proceeds in the highly acidic media, was calculated as 5.7x 102 dm3. mol-1·s-1 at 20°C. The temperature dependence of the rate constant was examined and the thermodynamic data for the reaction system were calculated.

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An analytical method for determing biotin as its 9-anthryl-diazomethane (ADAM) derivative by high performance liquid chromatography with fluorometric detection is described. The separation of the biotin-ADAM derivative was accomplished by passing the mobile phase of acetonitrile-water (65: 35) through the Zorbax ODS column (250 mm x 4.6 mm∅) at the flow rate of 1.1 ml/min. The wavelengths for excitation and fluorescence detection were 254 nm and 412 nm, respectively. A good linear relationship between peak height and injection amount was obtained in the range of 3 to 400 ng for biotin. The limit of quantification was 3ng; the relative standard deviation was 11.4% for 3 ng biotin. The present method is more sensitive than the conventional chemical method and more reliable than the microbiological methods.

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A new ion exchanger named "xanthogenized TOYOPEARL" (X-TYP) was prepared by the reaction of TOYOPEARL HW-40 (Toyo Soda Manufacturing Co. ) with carbon disulfide in aqueous sodium hydroxide solution. Mercury (II), copper (II ), lead(II), cadmium (II), nickel (II) and zinc(II) were collected completely from 50 ml of 1 x10-5 mol ⋅l-1 solution of each metal salts over the pH range of 0.1-10.0, O.1-10.0, 3.5-5.7, 4.4-5.4, 4.4-7.4 and 5.48.5, respectively, by stirring with 0.1g of X-TYP for 30 min at room temperature. Collection of each metals was incomplete in the presence of EDTA. Each metals except for mercury of 5.00 x 10-4 mmol were collected completely by column method with 0.3 g of X-TYP from 5l of test solution and recovered by elution with conc. nitric acid. The separation of copper and zinc was carried out as follows. Both 5.00 x 10-4 mmol of two metals were collected together by passing 500 ml mixed metal solution at pH 5.4 through a column packed with O.3g of X-TYP. Zinc was eluted with 2 mol⋅l-1 nitric acid and then copper left on X-TYP was eluted with conc. nitric acid. The separation of copper from other metals such as nickel, cadmium and lead was also successful by the similar procedure. Similarly, nickel was separated successfully from lead by elution with nitric acid (pH 3) after collection of two metals.

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A high performance liquid chromatographic method for ionic surfactants was developed with a macro porous ion-exchange resin (TSK GEL IEX 210 SC, IEX 220 SA) or a silica-based ion exchanger (Nucleosil 5 SA, 5 SB) as a stationary phase. A methanol solution of sodium perchlorate was used as a mobile phase in order to reduce the. hydrophobic interaction between sample ions and exchangers used. The capacity factor obtained for surfactant ions was inversely proportional to the concentration of perchlorate ions in the mobile phase. High column temperature improved the column efficiency. The cation-exchange chromatographic elution time for a tetra alkylammonium salt decreased with an increase in column temperature, whereas the anion exchange chromatographic elution time for an alkylbenzenesulfonate salt was independent of the temperature (Table 1, 2). The order of elution in homologous ionic solute was related to the organic moiety of solute, and the elution time decreased with increasing carbon numbers of the solute (Fig.1, 4, 5). This phenomenon was caused by the difference in the permeability of ionic solutes into the pores of ion exchangers. Commercial grade materials of linear alkylbenzenesulfonate (LAS) and ce-olefinsulfonate (AOS) could be separated from each other (Fig.3); the former surfactant eluted a little later after the latter one. According to this method, LAS could be determined in mixtures with octadecyl trimethylammonium chloride (OAC) and with poly (oxyethylene) nonylphenyl ether (NPE), and OAC could be determined in mixtures with LAS and with NPE (Table 4), since only either cationic or anionic species retained on the ion exchanger used.

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In order to obtain information on the dyeing mechanism of polyester fibers with disperse dyes, interactions between a polyester model and disperse azo dyes have been investigated by the analysis of visible absorption spectra in terms of a modified McRae's equation. From the results, a more quantitative estimation of the interactions was obtained. Methyl benzoate as a polyester model and the following disperse azo dyes were used: The shifts of wave number of the absorption makima of the dyes in various solvents and methyl benzoate were calculated by the McRae's equation. A linear relationship was obtained between the calculated and observed frequency shifts. The McRae's equation reasonably explained the visible absorption spectra of the azo dyes. The dipole-dipole shift of the azo dyes estimated from the equation was -400 - -1000 cm^-1 and/or 1-3kcal/mol in methyl benzoate solution. The dipole-dipole force was estimated to be 12-49% of the total interaction between disperse azo dyes and methyl benzoate.

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Synthesis of β-nitro ketones [2] from α, β-unsaturated ketones [1] was studied. In the reaction of 3-buten-2-one [1a] with sodium nitrite-acetic acid in THF, 4-nitro-2-butanone [2a] was obtained in 82% yield. When THF is displaced with DMSO in the above reaction, trans-3-octene-2, 7-dione [3] was formed in 56% yield together with 30% yield of 4-nitro-3butanone [2a]. Furthermore, the use of potassium nitrite instead of sodium nitrite in THF yielded 35% of the dimer [3] and 18% of 4-nitro-2-butanone [2a]. The reaction of α, βunsatur ated ketones [1] which did not bear substituents in the olefinic part with sodium nitrite-acetic acid in THF gave the corresponding, β-nitro ketones [2] in 42-82% yield.

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Relations between chemical structures and electrical conductivity were investigated for five glycine derivatives in aqueous and dimethyl sulfoxide solutions. Electric conductivity (σ)increased, as ion mobility increased and the activation energy for conductivity (E) decreased. Plots of E vs. log σ have a straight line for all the compounds. Ion mobility is considered to be a common factor governing conductivity of these compounds.

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Physical properties of poly(vinyl alcohol) in the relation with mixing in tank reactor during vinyl acetate polymerization have been studied. From the results on the standing stability of aqueous poly(vinyl alcohol) solution, the iodine coloration, the shrinkage behavior of the film on dry-heating and the others, it was found that crystallizability of poly(vinyl alcohol) was affected with mixing conditions in tank reactor for polymerization reaction. The branching of poly(vinyl acetate) was also affected by mixing and was closely related to the crystallizability of the corresponding poly(vinyl alcohol). It is concluded that the difference in crystllizability of the poly(vinyl alcohol)s arises from the difference in the degree of the branching of the poly(vinyl acetate)s, which given by the mixing.

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It has already known that cyanocobalt(II) complexes with various CN/Co ratios initiate the polymerization of methyl methacrylate (MMA) in an aqueous solution containing a surfactant under an atmosphere of hydrogen or nitrogen. However, it was found that in a concentrated solution of a surfactant the polymerization velocity of MMA by the complex with the CN/Co ratio of 2 under a hydrogen atmosphere was faster than that by the complexes with the other CN/Co ratios. The inhibition of the polymerization by addition of 2, 2-diphenyl-1-picrylhydrazyl suggested that the polymerization of MMA proceeded through a radical mechanism. It was considered that the polymerization was initiated by the donation of an electron from the complex with the CN/Co ratio of 2 to MMA. The effective surfactants for the polymerization were as follows; Nonionic: Tween series (except Tween 85), Brij series, Triton X 405. Anionic: Sodium dodecyl sulfate, Sodium dodecylbenzenesulfonate.

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Methacrylic acid (MAA), methyl methacrylate (MMA) and 2-(dimethylamino)ethyl methacrylate (DMA) were graft-copolymerized onto Nylon 66 fibers which were prepared by the interfacial polymerizaion. Physicochemical properties of the surfaces of the modified Nylon fibers were investigated from the standpoint of a binding process of Orange II. The isoelectric points of the grafted Nylon fibers were considerably and slightly lower for the MAAand MMA-grafted fibers, respectively, but much higher for the DMA-grafted fiber than that of the original fiber. In addition, the graft-copolymerization of the monomers onto the Nylon fibers brought about a remarkable increase in the specific surface area of the grafted fibers (Table 1). The amounts of Orange II bound to the Nylon fibers were in the order DMA->(original) MMA->MAA-grafted fibers and the binding process showed typical Langmuir adsorption isotherms (Figs.1-3). The standard free energies (ΔF°) and equilibrium binding amounts (n) obtained from Klotz plots varied with graft yield and adsorption temperature (Figs.4-9). These results are discussed on the basis of the changes in the isoelectric points and specific surface areas of the grafted fibers. The values -ΔF° and n of some DMA- and MAA- grafted fibers had the maximum points at about 50°C (Figs.5, 6, 8 and 9). From the thermodynamic parameters for the binding of Orange II to DMA- and MAA-grafted fibers (Table 2), the adsorption mechanism of Orange II on the grafted fibers is concluded to depend on the temperature and to be ascribed to hydrophobic interaction between the dye and the fibers.

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The deactivation of a V₂O₅/TiO₂ catalyst with deposited alkali metal salts in the reduction of NO with NH₃ and the regeneration of the deactivated catalyst were investigated. Alkali metal salts were deposited on the V₂O₅/TiO₂ catalyst (average diameter 1.0 mm) by an impregnation or spray method. Measurements were made in a flow-type packed bed reactor under atmospheric pressure at 350°C; inlet gas was a mixture of NO (500 ppm), SO₂ (0-1500 ppm), NH₃ (500 or 667 ppm), O₂ (5%), H₂O (10%), and N₂ and total flow rate was 1000 Ncm³/min (SV: 6 x 10⁴ h^-1).
The following results were obtained:
(1) The catalytic activity decreased with increasing the temperature at which alkali metal salts were deposited. In the reduction of NO in the absence of SOx, the degree of deactivation was remarkably affected by the kind of salts deposited: the apparent order being KCl≥K₂CO₃>NaCl>Na₂CO₃≥KNO₃≥K₂SO₄>NaNO₃>Na₂SO₄. Whereas, in the reduction of NO in the presence of SOS, the effect of the salt, which were transformed into sulfates, on the degree of deactivation was fairly: reduced.
The deactivation was mainly caused by the reaction of alkali metal salts with V₂O₅, leading to the formation of an inactive oxide complex.
(3) The catalysts deactivated in the reduction of NO in the presence of SOx, were almost completely regenerated by a washing procedure with water.

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Although adsorbability of mercury(II) ion on activated carbon is strikingly affected by pH, the adsorption mechanism has not been clarified. From the fact that activated carbon can reduce the dichromate ion and noble metal ions and mercury (II) ion has high oxidationreduction potential, it will be expected that mercury(II) ion can also be reduced by activated carbon. In this paper, the effect of pH on the adsorption of mercury (II) (Hg(NO3)2) and mercury( I ) (Hg2(NO3)2) ion on activated carbon and the oxidation states of mercury in equilibrium solution were investigated. Futhermore, the effect of pH on the reduction of mercury(II) ion was examined by measuring the amount of volatilized mercury in the presence of activated carbon. Both the amount and the oxidation states of residual mercury for mercury(II) ion were the same as those for mercury( I ) ion at pH below 5, and in this pH region, reduced mercury existed in equilibrium solution even when mecury(II) nitrate was used (Figs.5 and 6). At pH higher than 6, most of the residual mercury was mercury(II) ion whichever ion was used (Fig.6). The variation of oxidation states with pH corresponded to a degree of disproportionation reaction of mercury( I ) ion (Fig.4). In addition, mercury was volatilized from mercury (II) ion-activated carbon system over wide pH region and the maximum volatility was observed at the same pH as that giving maximum adsorbability for mercury(II) ion (Fig.8). From these results, it can be concluded that activated carbon reduces mercury(II) ion and adsorbes mainly metal mercury and that at pH higher than 6 the reducing ability of activated carbon decreases with the increase of pH.

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Dissolved oxygen (II) was stoichiometrically reduced by iron(II) within two minutes at pH higher than 8 in an air-tight system. Even in a continuous-flow system open to the air, the consumption of DO was proportional to the concentration of iron(II) added from 5 to 80 ppm as shown in Figure 5. On the basis of this relationship, iron(II) feed was automatically controlled by using a DO meter as a detector in the wastewater treatment process. Synthetic wastewater containing Cr(VI), Mn(VII), Cd(II), Zn(II), and Cu(II), whose concentrations varied from 5 to 20 ppm with time, was continuously treated by the present system and satisfying results were obtained.

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The effect of cationic and nonionic surfactants on the rate of the [Co(CN)₅]^3--catalyzed hydrogenation of styrene was investigated in the micellar and phase transfer reaction systems. Poly(oxyethylene)(23) dodecyl ether (Brij 35) was found to be useful for the promotion of the hydrogenation in the micellar reaction system. However the use of dociecyldimethyl(α-methylbenzyl)ammonium bromide (SUR 12) as a phase transfer agent resulted in more efficient acceleration of the reaction rate in comparison with the case of Brij 35. The effect of reaction conditions, such as molar ratio of [SUR 12]/[Co²⁺], on the hydrogenation rate was also discussed for the phase transfer reaction systems.

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Ti₂XS₃ (X=Si, Ge) were prepared from the stoichiometric mixture of TiS, X and S by reacting at 700-800°C for several hours and subsequent annealing at 430-460°C for several days in the evacuated silica tube. They are isomorphous, and belong to the triclinic system with space group of PI. The lattice parameters of the new compound, Ti₂iS₃, determined from X-ray powder data are a=6.691(2) Å, b=6.711(2) Å, c=8.367(2) Å α=90.69(2)°, β=111.62(2)°, γ=112.42(2)°, and Z=2. The X-ray powder diffraction data of Ti₂SiS₃are listed together with data of the synthetic Tl₂GeS₃. Assignment of infrared absorption bands was made for Ti₂SiS₃ and Ti₂GeS₃. Photoacoustic spectra of the two compounds are also reported.

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The effects of Ca²⁺ ion on decomposition and alteration of Lepidolite under alkaline hydrothermal conditions were investigated. The Ca²⁺ ion in NaOH-Ca(OH)₂ solution reacted with silicate ion to form almost insoluble calcium silicate hydrate residue. The extraction ratio of silicate ion could be reduced below 3%, while retaining that of Li+ ion more than 90% when the molar fraction of Ca(OH)₂ was adjusted at 0.2 in the Na0H-Ca(OH)₂ solution. Tobermorite was formed at 150-300°C and above O.4 molar fraction of Ca(OH)₂, and cancrinite and natrodavyne low temperature form at 200-350°C and below 0.4 molar fraction of Ca(OH)₂. Calcium content in the resulted calcium silicate hydrate residue increased with increasing of Ca(OH)₂ in the solution.

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The kinetics of the complexation reaction of quadrivalent metals [Th(IV), U(IV) and Zr(IV)]with Arsenazo III have been studied in strongly acidic media by using a stopped-flow specrophotometric method. In the complexation with thorium(IV), the rate-determining step is the following reaction; In the complexation with uranium(IV), it was assumed that the reaction proceeds through the following four competitive reactions: The complexation reaction path of zirconium(IV) with Arsenazo III could not be clarified due to the complication of the reaction mechanism.

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When a mixture of acridine and pyrrole in the molar ratio of 1: 2 was heated at 160°C, 9-(2-pyrrolyl)acridine [1a] and 2, 5-di(9-acridinyl)pyrrole [1b] were obtained in 33.0% and 30.0% yields, respectively. Other aromatic amines such as 2, 5-dimethylpyrrole, indole, imidazole, 2-methylimidazole and 3-methyl-1-phenyl-5-pyrazolone were also found to react with acridine to give [2], [3], [4], [5] and [6], respectively (Scheme 2). The reaction is considered to be a nucleophilic reaction of the anion of the aromatic amines to acridine (Scheme 1).

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A new class of 17H-bis[1, 4]benzothiazino[2, 3-a: 3, 2-c]phenothiazine [5] has been prepared by a novel synthetic procedure and their several properties were determined. The preparative method consisted of two steps. (a) The condensation of chloranil [2] with a zinc salt of 2-aminobenzenethiol [1] D in a molar ratio of 2: 1 in ethanol gave 1, 2, 4-trichloro-3Hphenothiazin3-one [3]J in a high yield. (b) The reaction of [3] with [1] in DMF at 150°C for 8 h afforded five derivatives of [5] in 25-68% yields. Compound [5a] was also obtained by the reaction of 6, 13-dichlorotriphenodithiazine [4a] with [1a] under conditions similar to (b). The structures of [5] were established on the basis of the elemental analyses, infrared spectra, and mass spectral data. The streak colors of the five compounds ranged from violet to green and their melting points were in the range 222-380°C (by DTA). Compounds [5] were found to have good light fastness as an organic pigment.

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