Synthesis as well as characteristic features of 3-chloromethyl-Δ ³-cephems (GCLE), a new potent intermediate for the synthesis of a wide variety of antibiotics of cepbalosporin family, are described. The synthetic scheme of GCLE starting from penicillin G consists of pyrolytic cleavage of penicillin sulfoxide leading to 4-(phenylsulfonylthio) azetidin-2-one derivatives, electrochemical ene-type chlorination of the N-substituent (3-methyl-3-butenoate) of the azetidinones, and subsequent construction of the cephem framework by ammonia-promoted recyclization. The phenylsulfonyl moiety works eectively for trapping the in situ generated sufenic acid in the rst step, as a protecting group in the ene-type chlorination, and as a good leaving group in the nal recyclization step. Our continuing eorts on the improvement of each of the sequen tial processes upto the level feasible for industrial production of GCLE deal with (1) elucidation of active chlorine species generated in the electrochemical chlorination, in turn, leading to the innovation of ene-type chlorination with molecular chlorine associated with particular hetero atom compounds, (2) recovery and recycle use of the phenylsulfonyl moiety, and (3) optimization of the cyclization of the azetidinones into GCLE with ammonia. Deprotection of p-methoxybenzyl and diphenylmethyl ester moietyin a phenol matrix, which is an essential stage for the synthesis of antibiotic drugs, as well as demonstrations of the synthetic utility of GCLE are also described.

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Antisense strategy is one of the promising methods for curing incurable diseases such as cancer and AIDS by regulating gene expression. Oligonucleotides and their analogs have been innovated and used for the purposes. However, stereoisomerism of antisense molecules that intrinsically exists in such molecules contains a crucial problem for the future development of the strategy. In this report, the effects of stereoisomerism on antisense effects were studied by reversed phase HPLC, UV and CD spectroscopy. As antisense molecules, oligonucleoside phosphoramidates and oligonucleoside phosphorothioates both of which contain stereoisomeric modified phosphate linkages, were synthesized and characterized. As results, it was found that there exist large differences in solution structure and that the stereoisomerism may have crucial effect on the antisense gene regulation.

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Before the IR spectral measurement to ascertain the formation of 2-amino-1-methylpyridinium cation (abbrev. pyridinium cation) in the aquous solution of 1-methyl-2 (1H) -pyridinimine (abbrev. pyridinimine) is done, the normal coordinate calculation within the ab initio 6-31G level was carried out for the optimized models of pyridinium cation and pyridinimine-HC1 salt using the Gaussian 90 source program on a FACOM VP-100E computer to make sure the IR spectral features of pyridinium cation. The optimized model of the latter compound showed that the HC1 salt is consisted of pyridinium cation and chloride anion moieties. Therefore, the IR spectra of the two compounds were expected to be close to each other. From the present calculation the following conclusion was drawn. (1) The strong two bands appear in the region 3500 to 3000 cm^-1. These bands were assigned to the N-H stretching vibration. Their band position, band separations and relative intensities are different from each other due to the existence of chloride anion or no existence. Pyridinimine has no such strong two bands in this region. (2) Pyridinium cation and cation moiety have four prominent bands in the region 1700 to 1500cm^-1, while pyridinimine has the three bands in the same region. The band at the highest wavenum ber side among the four bands is strong in intensity and it was assigned to the scissoring vibration of the amino group of the cation. Pyridinimine has no such band in the same region. Therefore, the corresponding band of cation is a key band for the recognition of pyridinium cation from the IR spectrum of pyridinimine. (3) The band assignment of the IR spectrum of pyridinimine hydroiodide was done by making reference to the results of the normal coordinate treatment of pyridinimine hydrochloride model. The correspondence between the IR spectrum of the HI salt and the results of the normal coordinate treatment of the HC1 salt model is relatively good in the band position but poor in the relative intensity of the band.

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Synthesis of ZSM-5 type zeolites has been carried out using various structure-directing reagents such as amine, diamine, amino alcohol, hydrocarbon and alcohol as well as tetrapropylammonium bromide (TPABr). The role of the directing reagent and the properties of zeolites synthesized, however, have not been sufficiently clarified. In this paper, synthesis of ZSM-5 type zeolites was conducted using various aliphatic alcohol and their properties were investigated in detail. It was found that the highly crystalline ZSM-5 type zeolites were synthesized using 1-butanol and 1-hexanol (Table 1). In the case of 1-butanol, the crystallinity of zeolite was increased with an increase in 1-butanol/SiO₂ ratio of the starting synthesis mixture and the highest crystallinity was obtained for over 1 of 1-butanol/SiO₂ ratio (Table 2). The production of cristobalite as by-product was considerably depressed by addition of 1-butanol. These results indicate that 1-butanol acts as the structure-directing reagent. The SiO₂/Al₂O₃ ratios of zeolites synthesized using 1-butanol were lower than those of the starting synthesis mixtures. The region of SiO₂/Al₂O₃ ratio (30-150) was much smaller than that of zeolites with TPABr (Table 3). The Al-free zeolite, silicalite, could not be prepared using 1-butanol. Figure 4shows the FT-IR spectra of hydroxyl groups of HZSM-5 zeolites synthesized using (A) 1-butanol and (B) TPABr. The spectra of HZSM-5 from TPABr were characterized by two well-defined absorptions at 3605 and 3740 cm^-1. The former band has been assigned to stretching vibration of an acidic bridged OH of Si (OH) Al, while the latter one to terminal Si-OH. On the other hand, two peaks at 3605 and 3740 cm^-1 were also observed in the spectra of zeolites using 1-butanol. However, the intensity of the peak at 3740 cm^-1 was very weak. The drastic decrease in the intensity of the peak at 3740 cm^-1 may suggest the concentration of the internal Si-OH groups (structure defects) is relatively small. This is also confirmed by the fact that the amount of water adsorbed on zeolite synthesized with 1-butanol was smaller than that on zeolite with TPABr.

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To clarify the crystal growth process of zeolite under hydrothermal synthesis condition, a new type apparatus for the in-situ observation was developed. In the present work, the growth behavior of silicalite crystals from clear aqueous solutions was studied using the apparatus. Effects of the crystallization tern perature and the composition of synthesis mixture on the growth rate and the morphology of specified crystal were investigated systematically. The crystal length growth rate (R_l) and width growth rate (R_w) increased significantly with an increase in the temperature. The morphology was also affected by the temperature.
Next, effects of the composition of synthesis mixture on the crystal growth rate and the morphology was investigated using the following synthesis mixtures.
(1) _xTPA₂O 0.05Na₂O SiO₂ 300H₂O ( x = 0.012- 0.1)
(2) 0.05TPA₂O _yNa₂OSiO₂ 300H₂O ( y=0.025- 0.2)
(3) 0.05TPA₂O 0.05Na₂O _zSiO₂300H₂O ( z = 0.5- 2)
(4) 0.05TPA₂O 0.05Na₂O - SiO_{2 w}H₂O ( w= 100-1000)
The growth rate and the crystal morphology were affected markedly by changing the composition of synthesis mixture. The following relationships were obtained;
R_l∝ (TPA⁺)^0.389(OH^-)^0.518(SiO₂) ^-0.196(6H₂O) ^-0.745
R_w∝ (TPA⁺)^0.675(OH^-)^1.05(SiO₂) ^-0.226(H₂O) ^-1.12
R_l/R_w∝ (TPA⁺)^-0.286(OH^-) ^-0.528(SiO₂)^0.0296( H₂O)^0.369

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From the viewpoints of removal, recovery and preconcentration of organic anions in water, the direct fixation of carboxylate ions into the precipitates of the layered double hydroxides (LDHs), [M²⁺_1-xM³⁺_x(OH)₂][A^n-_x/n⋅ yH₂O], by coprecipitation method has quantitatively been investigated. When 0.2 mol dm^-3 mixed solution of MgCl₂ and AlCl₃ or ZnCl₂ and AlCl₃ ( M²⁺/ Al³⁺= 2) was added dropwise into the 2-200 mmol⋅ dm^-3 carboxylate solution at adjusted pH, the linear saturated aliphatic carboxy late ions with long carbon chain such as sebacate, dodecanedioate and laurate, and also the aromatic carboxylate ion such as terephthalate were incorporated highly in the LDH precipitates. Further, the extent of the coprecipitation became higher with the increase of carbon number of the guest aliphatic carboxylate ions. The optimum conditions were found as follows; Al³⁺ / A^n- molar ratio = 4-8, reaction te mperature range 25-40° C, p H about 10 (Mg-Al system) and 6 (Zn-Al system). Though the crystal linity of the LDH precipitates was quite low, the carboxylate ions were found to be incorporated in a parallel configuration to the positively charged hydroxide layers when the amount of the guest anion was small, while those in a tilted configuration to the hydroxide layers in the case of large amount of the guest a nion. When the initial concentration of the carboxylate ions was quite low or the solution contained a lot of inorganic anion, the extent of the coprecipitation of the carbwdate ions was decreased. However, it could be improved easily by increasing the addition of t he metal ion solutions. In conclusion, the possible fixation method based on the new mechanism (coprecipitation into the interlayer of LHD) can be proposed.

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The insoluble matters which produced by refluxing for 8 h the methanolic, ethanolic and 1-propanolic solutions of bis (acetato) bis (alkylimidazoles) copper (II) ( [Cu (CH₃COO)₂ (1-CH₃ · im)₂] (1) and [Cu (CH₃COO)₂ ( R · Him₂)] R: 2-CH₃(2), 2-C₂H₅(3), 2 (CH₃)₂ CH (4) and 4-CH₃ (5) ) were characterized by the elemental analyses, and the magnetic and spectral data, and the thermal properties were investigated.1 did not produce the insoluble matter in the alcoholic solutions. [Cu (2-R · im) (OR)]_n, (OR: OCH₃, OC₂H₅ and OC₃H₇) were obtained from the alcoholic solutions of 30-7.5 mM 2 and 3, and [Cu ( 2- (CH₃)₂CH · im ) (OC₃H₇)]_n, was obtained from the 1-propanolic solution of 30 and 15 mM 4. While, [Cu (4-₃· im)₂]_n, was obtained from the alcoholic solutions of 30-7.5 mM 5. The magnetic moments were 0.82-1.07 BM for [Cu (2-R · im) (OR)]_n, and 1.69 BM for [Cu (4-CH₃ · im)₂]_n, respectively. These polynuclear complexes seem to contain a chain structure consisting of the square planar copper unit. The pyrolysis process of these polynuclear complexes were discussed.

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Calcium, strontium, and barium alkoxides reacted with primary alkyl halides such as hexyl bromide, octyl bromide, and benzyl chloride at 70-100° C in DMSOalcohol (1/1). The substitution reaction gave the corresponding primary alkyl ethers in 72 94% yields. The alkaline earth metal salts of ethylene glycol and 2-pr opyn-1-ol, which have two reactive points, were heated with benzyl chloride, and gave a mono-substituted product exclusively, although a similar reaction of alkali metal salts is known to give both mono and di-substituted products. On the other hand, alkaline earth metal phenoxide and naphthyl oxide reacted with primary alkyl substrates in DMSO to afford aryl alkyl ethers in high yields. Furthermore, secondary alkyl substrates also reacted with alkaline earth metal aryl oxides to give secondary alkyl aryl ethers in 5671% yields. Isopropyl iodide, isopropyl bromide, isopropyl methanesulfonate, s-butyl iodide, and s-butyl methanesulfonate were used as the secondary alkyl substrate. According to the previous study, the reaction of secondary alkyl substrates with sodium alkoxides and aryl oxides gave only 20 30% of ethers. Therefore alkaline earth metal salts are much more selective than alkali metal salts in the substitution reactions. Although calcium salts are less reactive than strontium and barium salts, calcium salts are more selective and useful for organic synthesis from the viewpoints of safety and cost.

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A mechanistic study has been performed to clarify the reversible change of light scattering properties of the polymer films involving dispersed crystals of fatty acids as microspheres, using X-ray diffractometry, electron microscopy, DSC and supersonic micrography. Special emphasis was laid on two phenomena. (a) The crystallization temperatures (T_c) of the fatty acids remarkably changed, sensitively depending on the degree of melting of the fatty acids at the starting temperature for cooling. The cool ing from far above the melting points lowered T_c about 30° C from the melting point of the bulk crystals. By contrast, T_c was rised when the cooling started from the temperature range of melting. These properties were evidenced by in situ X-ray diffraction measurements of the crystallization processes. (b) The relationship between T_c and the glass transition temperature (T_g) of the polymer matrix definitely influenced the light scattering properties. It was confirmed also that the light scattering state was achieved when T_c was lower than T_g. We have drawn a conclusion that the light scattering property is ascribed to the formation of voids in the micrcspheres, which are formed by the reduction in the volume of fatty acids during the crystallization at the temperatures below T_g of the polymer matrix. The films loses the light scattering property by annihilation of the voids when the crystal surfaces of fatty acids melt upon heating. The nonscattering conditions are maintained even upon the cooling in case that the crystallization occurrs above T_g. The formation and the annihilation of the voids was confirmed as the change of film thickness, and by supersonic micrography.

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Several single layer electroluminescent (EL) devices made of molecularly-doped polymer films in which component dyes and their compositions were systematically varied were fabricated. Their EL emission characteristics were examined. Polyvinylcarbazole (PVK), which possesses hole transporting capability, was used as polymer binder and device performances were compared with corresponding devices with inert polymer binder, and little difference was found between two types of devices. Double-layer and triple-layer type EL devices were fabricated using PVK and an oxadi azole derivative, OXD-7 for electron and hole blocking layers, respectively, and the effect of the introduction of charge-blocking layers has been investigated. Though reduction of hole injection and increase of operat ing voltage was observed, current quantum efficiency was increased with the introduction of PVK as the electron-blocking layer. The introduction of charge-blocking layers at both sides of electrodes resulted in the increase of quantum efficiency by about one order of magnitude. By the introduction of chargeblocking layers, the amount of holes and electrons which go through emissive layers without recombination were drastically reduced. This effect was found to contribute for marked increases of current quantum efficiencies.

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Contents of halide ions (F^-, Cl^-, Br and I^-) of twelve hot spring waters in the Kusatsu-Shirane volcano area were determined using ion chromatography. High correlations were observed among those ions, which indicated that they were of the same origin, that is, they were all derived by the volcanic activity of Mt. Kusatsu-Shirane. Secular changes in F^-, Cl^- and Br^- contents of Kusatsu-Yubatake and Bandaiko hot spring waters and Yugama lake water since around 1970 were presented. Increases in most of those contents are observed in recent years.

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Direct and benzophenone (BP)- or 4, 4'-bis (dimethylamino)benzophenone (BAB) -sensitized valence photoisomerizations of 3-phenyl-2, 5-norbornadiene-2-carboxylic acid (PNC) in acetonitrile were found to efficiently proceed affording the corresponding quadricyclane derivative in quantum yields comparable to each other. Kinetic and thermodynamic considerations of the BP, BAB and 4-dimethylaminobenzophenone (DAB) -sensitized photoisomerizations of PNC suggested that the BP-sensitized reaction proceeds by an energy-transfer pathway whereas an electron-transfer pathway also participates in the BAB- and DAB-sensitized reactions.

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The interaction between copper phthalocyanine (CuPC) and poly (methyl methacrylate) (PMMA)was investigated. Th e differrence spectrum between 10^-5 mol dm^-3 CuPC + 0.01 mol dm^-3PMMA acetone solution and 10^-5 mol dm^-3CuPC acetone solution showed a mini. at 625 nm and a maximum at 640 nm and the existence of the relatively strong interaction between CuPC and PMMA were recognized. The dynamic modulus of PMMA including 1 mol% CuPC was 2.5 times greater than that of pure PMMA. It was shown by employing SAICAS method that cutting strength of PMMA including 1 mol% CuPC was lower than that of pure PMMA. Comparison of the thermal gravitation curve of pure PMMA with that of PMMA including CuPC indicated that heat resistance of PMMA including CuPC was higher than that of pure PMMA.

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