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Through-bond ¹³C−¹³C and ¹³C−¹H correlations in the crystal structure of cellulose II were determined by the two-dimensional (2D) refocused INADEQUATE and MAS-J-HMQC spectra of the mercerized cellulose, which was biosynthesized by Acetobacter xylinum ATCC 10245 from the uniformly labeled glucose (d-(U-¹³C6)glucose). Mercerization of the bacterial cellulose was achieved in a solution of 20% NaOH in water for 2 weeks. In the 2D INADEQUATE spectrum of cellulose II, two sets of the through-bond ¹³C−¹³C connectivities from C1 through C6 were clearly observed, which enabled us to completely assign the complex 1D CP/MAS ¹³C spectrum of cellulose II. Following the ¹³C assignment, the ¹H resonance for the proton(s) attached to each carbon of cellulose II could be assigned by use of the 2D MAS-J-HMQC spectrum of the mercerized cellulose.

Using the two-dimensional (2D) refocused CP-INADEQUATE spectra of natural abundance Cladophora and tunicate celluloses, we determined the ¹³C homonuclear through-bond correlations of cellulose Iα and Iβ, respectively. Two sets of the ¹³C−¹³C connectivities from C1 through C6 were observed in the 2D INADEQUATE spectrum of the respective cellulose where two directly bonded carbons share the common frequency in the double quantum dimension, which indicated that both cellulose Iα and Iβ contain two magnetically nonequivalent anhydroglucose residues in the unit cells. After the ¹³C assignment of each carbon of the cellulose Iα and Iβ, assignments of the ¹H chemical shifts of protons attached to each carbon of the both allomorphs were performed by use of the 2D MAS-J-HMQC spectra of the cellulose samples for the first time. These spectra gave the through-bond ¹³C−¹H correlations, which allowed the assignment of the ¹H chemical shifts of protons that bind to C1, C3, C4, and C6 of the cellulose Iα and Iβ. From the differences in the ¹³C and ¹H shifts of cellulose Iα and Iβ, it was revealed that the primary difference between two forms of cellulose I was in the conformations of anhydroglucose residues contained in the cellulose chains. In addition, the conformational difference in the torsion angle around the β-1,4 linkage between cellulose Iα and Iβ was suggested by the notable differences in their ¹H chemical shifts of protons attached to C1.

For the assignment of ¹³C resonance for C2, C3, and C5 of cellulose IIII, ¹³C-enriched celluloses were biosynthesized by Acetobacter xylinum (A. xylinum) ATCC10245 in the culture medium containing d-(2-¹³C), d-(3-¹³C), or d-(5-¹³C)glucose. After the ¹³C-enriched celluloses and Cladophora cellulose were converted into IIII allomorph by the ethylenediamine treatment, cross-polarization/magic angle spinning (CP/MAS) ¹³C NMR spectra of these cellulose IIII samples were measured. By comparison of the CP/MAS ¹³C NMR spectrum of Cladophora cellulose sample with those of the ¹³C-enriched celluloses, ¹³C resonance lines of the cellulose IIII were completely assigned for the first time. As a result, all carbons of cellulose IIII were shown in singlet in the CP/MAS spectrum of cellulose IIII, which suggests that cellulose IIII is made up of one kind of glucopyranose residue.

In the photochemical bis-germylation of C60 with 1,1,2,2-tetrakis(2,6-diethylphenyl)-1,2-digermirane (1), a cycloadduct (2) is obtained in high yield for the first time. Spectroscopic analysis and theoretical investigation confirm that 2 (which has C1 symmetry) results from 1,4-cycloaddition. Control experiments and laser flash photolysis experiments suggest that an exciplex intermediate is responsible for the formation of 2. The redox properties of 2 were examined by differential pulse voltammetry.

In quasi-one-dimensional conductor β-Na.33V2O5, the commensurate C.D.W.(dimerization) phase transition about 180 K was found by the magnetic resonance and X ray diffuse scattering studies. The pair formation of magnetic V4+ ions in site I chain has been discussed on the basis of the spin-lattice relaxation time of 23Na and 51V nuclei and the anisotropic EPR line width.In case of β-LixV2O5 (x=0.36), the interesting two phase transitions were observed, 1) the incommensurate C.D.W. phase appears about 220 K, 2) below 170 K, this C.D.W. phase (qb=0.53) splits two sublattice of the commensurate C.D.W. phase (qb=0.5) and the I.C.C.D.W. phase (qb=0.57). The magnetic resonance studies of the single crystals of β-LixV2O5 show that there occur the microscopic changes of the electronic structure corresponding to these phase transitions.

Ionic motion of a divalent cation, Ba2+, in a single crystal of Ba−Al-priderite was studied using 27Al as an NMR probe. Several paris of satellite peaks due to electric quadrupole interaction were observed superposed on broad satellite tails on both sides of the main peak of 27Al. These peak pairs indicate the existence of some stable three-dimensional configurations of Ba2+ions in the structure, and the broad shoulders show a random substitution of Al3+for Ti4+sites. The temperature dependence of the spinlattice relaxation time T1*measured in the temperature range from 161 to 1176 K was analyzed by a curve fitting method on the assymption that there are two types of Ba2+ions. An activation energy of 0.47 eV was obtained for the motion of Ba2+ions which are easy to move, and a broad distribution of activation energies spread over a range from 0.95 to 2.45 eV was obtained for the motion of Ba2+ions which form a three-dimensional honeycomb framework and are hard to move.

We succeeded in developing of a new method for in vitro poly(3-hydroxybutyrate) (P(3HB)) synthesis with coenzyme A (CoA) recycling. Thiophenyl (R)-3-hydroxybutyrate was used as a precursor for the monomer, (R)-3-hydroxybutylCoA ((R)-3HBCoA). The (R)-3HBCoA was synthesized by the ester exchange reaction between thiophenyl (R)-3-hydroxybutyrate and CoA. Although the polymerization reaction in the buffer (water phase) was performed, the reaction did not occurred. The results of a PHA synthase assay in the presence of thiophenol suggested that the reaction was inhibited by a small amount of thiophenol. To avoid the inhibition of PHA synthase by thiophenol, a water−organic solvent two-phase reaction system was developed for the polymerization reaction. The water−organic solvent two-phase reaction system has been used previously for the bioconversion of substrates with low solubility in water; it was used to remove thiophenol released during the ester exchange reaction from the water phase. Thiophenyl (R)-3-hydroxybutyrate and PHA synthase were dissolved in the organic solvent and water phases, respectively. Ester exchange between thiophenol and CoA occurs at the interface of water and the organic solvent phase, and the (R)-3HB 3-hydroxybutylCoA synthesized was polymerized sequentially by PhaC. The organic solvents with high a logPow of more than 3.9 such as hexane, octane, decane, or dodecane were found to be suitable for the organic solvent phase in the two-phase system. The polymerization reaction mixture showed signs of turbidity in 2 h, after which white precipitates formed. The structural analyses by ¹H NMR spectroscopy indicated that the product was P(3HB). The weight-averaged molecular weight and molecular weight distribution of P(3HB) synthesized were found to be 1.6 × 10⁶ and 2.9, respectively. The maximum yield of P(3HB) based on thiophenyl (R)-3-hydroxybutyrate was 47%.

In quasi-one-dimensional conductor MxV2O5where the mixed valent V4+and V5+ions from zig-zag chains, the CDW state were observed below about 200 K in monoclinic phases by X-ray diffraction. The 51V Knight shift results show the spin-singlet ground state of V4+ion pair (‘bipolaron’) is realized.