Synthesis of γ-zirconium phosphate by the fluoro-complex method and the intercalation behavior of some α-diimines

The ammonium form of -zirconium phosphate has been synthesized by the direct precipitation method from fluorozirconate solution in the presence of ammonium dihydrogen phosphate. The hydrogen form Zr(HPO₄)₂ · 2H₂O, was obtained by acid treatment of the ammonium form -Zirconium phosphate , Zr(HPO₄)₂ · H₂O, with a relatively large particle size resulted from fluorozirconate solution in the presence of concentrated orthophosphoric acid. The intercalation behavior of such -diimines as 2,2-bipyridine (bpy) and 1,10-phenanthroline (phen) toward -zirconium phosphate was investigated, and it was found that about 0.2 mol of bpy and 0.5 mol of phen have been incorporated respectively per one mol of the host, with the expansion of interlayer distances. Further incorporation of Cu(H) ions into the interlayer space of these intercalates was possible. The bpy intercalate took up more Cu(II) ions than -zirconium phosphate, indicating that effective pillars are constructed between layers and the ion exchange of Cu(II) ions is facilitated thereby.     

Design of novel inorganic-organic hybrid materials based on iron-chloranilate mononuclear complexes: characteristics of hydrogen-bond-supported layers toward the intercalation of guests

Novel intercalation compounds constructed from the common two-dimensional hydrogen-bond-supported layers and functional guests [(H(0.5)phz)(2)[Fe(CA)(2)(H(2)O)(2)].2H(2)O](n)(1), ([Fe(Cp)(2)][Fe(CA)(2)(H(2)O)(2)])(n)(2), ([Fe(Cp*)(2)][Fe(CA)(2)(H(2)O)(2)])(n)(3), and [(TTF)(2)[Fe(CA)(2)(H(2)O)(2)]](n)(4) (H(2)CA = chloranilic acid, phz = phenazine, [Fe(Cp)(2)] = ferrocene, [Fe(Cp*)(2)] = decamethylferrocene, TTF = tetrathiafulvalene) are described. The guest cations are introduced between the ([Fe(CA)(2)(H(2)O)(2)](m-))(l) layers by electrostatic (1-4) and pi-pi stacking (3, 4) interactions. [Fe(Cp*)(2)](+) cations in 3 are stacked on each other making tilted columns which are included in the channel created by the chlorine atoms of CA(2-) dianions. TTF cations in 4 are stacked face to face with two types of S...S distances (type A; 3.579(3) A, and type B; 3.618(3) A) making a columnar structure. The TTF cations in the stacked column have a head-to-tail arrangement with respect to the iron-chloranilate layer. M?ssbauer spectroscopy suggests that [Fe(CA)(2)(H(2)O)(2)](m-) anion in 3 is consistent with high-spin (S = 5/2) iron(III) ions and [Fe(Cp*)(2)](+) in the low-spin (S = 1/2) iron(III) ions. In 4, M?ssbauer spectroscopy shows high-spin iron(II) ions (IS = 1.10 mm.s(-1) and QS = 1.66 mm.s(-1) at 297 K) and high-spin iron(III) ions (IS = 0.42 mm.s(-1) and QS = 1.27 mm.s(-1) at 297 K), suggesting that the anionic layer of iron-chloranilate has a valence-trapped mixed-valence state. At the temperature range of 77-300 K, the compounds 1, 2, and 3 are EPR silent, whereas the EPR spectrum of 4 shows two types of signals with g = 2.008 indicating the radical form of TTF.     

Highly selective anti-markownikoff type oxidation of olefinic bonds of allylic alcohol derivatives. Specific synthesis of β-alkoxy α-phenylseleno carbonyl compounds

On treatment with diphenyl diselenide and benzeneseleninic anhydride, 3-$\text{t}$-butyldimethylsiloxy-1-alkenes were converted to the corresponding α-phenylseleno aldehydes exclusively.     

Penetration of bovine serum albumin into dipalmitoylphosphatidylglycerol monolayers: direct observation by atomic force microscopy

The penetration of bovine serum albumin (BSA) into dipalmitoylphosphatidylglycerol (DPPG) monolayers was observed using atomic force microscopy (AFM) and surface pressure measurements. The effects of surface pressure, amount of BSA and the addition of ganglioside GM1 (GM1) were investigated. The surface pressure of the DPPG monolayer was increased by the penetration of BSA, and the increase in surface pressure was greater in the liquid-expanded film than that in the liquid-condensed film. The AFM images indicated that BSA penetrated into the DPPG monolayer. The amount of BSA that penetrated into the DPPG monolayer increased with time and with the amount of BSA added. On the contrary, the AFM image showed that BSA penetration into the mixed DPPG/GM1 (9 : 1) monolayer scarcely occurred. GM1 inhibited the penetration of BSA into the DPPG monolayer.     

N-Arylpiperazine-1-carboxamide derivatives: a novel series of orally active nonsteroidal androgen receptor antagonists

A novel series of N-arylpiperazine-1-carboxamide derivatives was synthesized and their androgen receptor (AR) antagonist activities and in vivo antiandrogenic properties were evaluated. Reporter assays indicated that trans-2,5-dimethylpiperazine derivatives are potent AR antagonists, and in this series trans-N-4-[4-cyano-3-(trifluoromethyl)phenyl]-N-(2,4-difluorophenyl)-2,5-dimethylpiperazine-1-carboxamide (18 g, YM-175735) exhibited the most potent antiandrogenic activity. Compared to bicalutamide, YM-175735 is an approximately 4-fold stronger AR antagonist and has slightly increased antiandrogenic activity, suggesting that YM-175735 may be useful in the treatment of prostate cancer.     

The chloroform extraction of nickel with oxine from perchlorate and sulfate solutions

Nickel-oxine complexes extracted from perchlorate and sulfate solutions with chloroform were isolated and their compositions were determined. They were Ni₂(Ox)₃(HOx)₃ClO₄ from perchlorate solution at low pH and Ni₂(Ox)₄(HOx)₂ from perchlorate solution at high pH or from sulfate solution. The extraction equilibria, 2Ni²⁺+6HOx(o)+ClO^-₄?Ni₂(Ox)₃(HOx)₃ClO₄(o)+3H⁺, 2Ni²⁺+ 6HOx(o)?Ni₂(Ox)₄(HOx)₂(o)+4H⁺ and Ni₂(Ox)₃(HOx)₃ClO₄(o)?Ni₂(Ox)₄ (HOx)₂(o)+H⁺+ClO^-₄, were proposed and the equilibrium constants were determined to be 10^7.58,10^-0.82 and 10^-8.75, respectively, at ionic strength 0.1 and 20°.     

N(2)-phenyldeoxyguanosine: modulation of the chemical properties of deoxyguanosine toward one-electron oxidation in DNA

We have shown here that (1) substitution of an exocyclic amino group of dG is effective in modulating the chemical properties of dG toward one-electron oxidation and (2) decomposition of the guanine radical cation was effectively suppressed near dPhG. These results indicate that dPhG is a prototype of nucleosides functioning as an intrinsic antioxidant of duplex DNA toward one-electron oxidation.     

Melting behavior of poly(3-hydroxybutyrate) investigated by two-dimensional infrared correlation spectroscopy

The melting behavior of a bacterially synthesized biodegradable polymer, poly(3-hydroxybutyrate) (PHB), was investigated by using generalized two-dimensional infrared (2D IR) correlation spectroscopy. Temperature-dependent spectral variations in the regions of the C-H stretching (3100-2850 cm(-1)), C=O stretching (1800-1680 cm(-1)), and C-O-C stretching (1320-1120 cm(-1)) bands were monitored during the melting process. The asynchronous 2D correlation spectrum for the C=O stretching band region resolved two crystalline bands at 1731 and 1723 cm(-1). The intense band at 1723 cm(-1) may be due to the highly ordered crystalline part of PHB, and the weak band at 1731 cm(-1) possibly arises from the crystalline part with a less ordered structure. These crystalline bands at 1731 and 1723 cm(-1) share asynchronous cross peaks with a band at around 1740 cm(-1) assignable to the C=O band due to the amorphous component. This observation indicates that the decreases in the crystalline components do not proceed simultaneously with the increase in the amorphous component. In the 3020-2915 cm(-1) region where bands due to the asymmetric CH3 stretching and antisymmetric CH2 stretching modes are expected to appear, eight bands are identified at 3007, 2995, 2985, 2975, 2967, 2938, 2934, and 2929 cm(-1). The bands at 2985 and 2938 cm(-1) are ascribed to the amorphous part while the rest come from crystal field splitting, which is a characteristic of polymers with a helical structure.     

Asymmetric synthesis of 1-deoxynojirimycin and its congeners from a common chiral building block

A new, promising chiral building block 9 for the synthesis of 1-deoxy-4,5-trans-oriented azasugars such as 1-deoxynojirimycin (1) was prepared in only four steps from the Garner aldehyde 10 using catalytic ring-closing metathesis (RCM) for the construction of the piperidine ring. In practical test, the first synthesis of all four isomers (1 and 6-8) of trans-4,5-orientated 1-deoxyiminosugars using 9 as a common chiral building block was demonstrated.     

Satellites and loss structures of core-electron peaks in x-ray photoelectron spectra of alkali fluorides

Structures consisting of several peaks were clearly observed in the loss band regions of core electron peaks in the X-ray photoelectron spectra of KF, NaF and LiF. It is shown that, although these structures very much resemble the electron energy loss spectra of the salts obtained using an externally produced electron beam, the energies and intensities of some peaks are dependent upon the ionizing core levels. One peak definitely attributable to an intrinsic satellite was found in the loss band region of F 1s spectrum of each salt, which was concluded to be due to the shake-up process associated with F 2p → F 3p excitation.