Studies on intramolecular nh-bridging in aromatic compounds. Part 3 [1–3]

A study was made of the use of calcium oxide as a catalyst at a temperature of 400–700° for the dehy-drocyclization of four primary arylamines: 2-aminobiphenyl, 1-aminotriphenylene (5c) , 2-phenoxyaniline, and N-(2-aminophenyl)pyrrole. Maximal yields of cyclized products isolated were 53% (carbazole), 52% (4H-naphtho[1,4-def]carbazole), 18% (phenoxazine), and 0%, respectively. Comparison is made with reported cyclizations of the corresponding nitro and azido starting materials. In one case, treatment of I-nitrotriphenylene with triethyl phosphite produced mainly diethyl N-(1-triphenylenyl)phosphoramidate (51%). Mono- and hemihydrochlorides of 5c are described. A mechanism for the catalyzed dehydrocy-clization is proposed.     

Grassmann manifold of aJH-algebra

We study the set of rankp idempotents in a topologically simple Hilbert Jordan algebra (JH-algebra for short). To produce the differential geometric structure on, we establish Jordan algebraic results concerning the structure of some two-generator subalgebras. We identify geodesics, the Riemannian distance and the sectional curvature of by using the Jordan algebraic structure.     

Electron spin relaxation of some alkane cation radicals as an indicator of dynamics between the distorted structures

ESR saturation phenomenon was observed for various alkane cation radicals derived from cyclohexane, propane and norbornane in frozen halocarbon matrices at 4 K. In addition to spectral diffusion by spin-spin interaction between the radicals, which is a common mechanism of ESR relaxation in the solid state, isotropic hyperfine modulation by the dynamics between the equivalent distorted structures was found to be very important for those centers which show Jahn-Teller (JT) or pseudo-JT effects. The effect of annealing of the sample at 77 K is also discussed.     

Conversion electron Mössbauer spectroscopy using a CAMAC data acquisition system (KODAQ)

For simple depth selective conversion electron Mössbauer spectroscopy (CEMS) by using a He+CH₄ proportional counter, a flexible and versatile CAMAC data acquisition system (KODAQ) which works on a popular Japanese personal computer PC9801VX (NEC) was applied. It is demonstrated that CEM spectra of the oxidized Fe thin film which is composed of Fe₃O₄, Fe_1–xO and -Fe metal are successfully obtained.     

Total synthesis of merrilactone A

Merrilactone A (1) has been shown to possess neurotrophic activity and thus is expected to hold therapeutic potential in the treatment of neurodegeneration diseases. In this paper, we report the total synthesis of (+/-)-1, employing, as key steps, a novel desymmetrization protocol of meso-diketone to construct the core cis-bicyclo[3.3.0]octyl system of 1 (3 --> 2) and a radical cyclization to install the highly congested C9-quaternary carbon (16 --> 17).     

Measurement of the product ion ratio N4+/N3+ in the radiolysis of nitrogen

The ratio of N₄⁺ to N₃⁺ formed in the radiolysis of gaseous nitrogen has been measured to be 4.7 ± 0.4 using a time-resolved atmospheric pressure ionization mass spectrometer. The limit of error has been evaluated from the ion mass discrimination of the apparatus.     

Synthesis of carbazole,acridine, phenazine, 4H‐benzo[def]carbazole and their derivatives by thermal cyclization reaction of aromatic amines

A variety of nitrogen‐containing heterocycles were synthesized by passing vapors of aromatic amines over calcium oxide at 450–650 °C under nitrogen carrier gas. Reaction of 2‐aminobiphenyl 3a at 560 °C gave carbazole 4 in 80% yield. Reaction of 2, 2′‐diaminobiphenyl 3b afforded a mixture of carbazole 4 and 4‐aminocarbozole 6b. In the case of 2‐amino‐2′‐nitrobiphenyl 3c, benzo[c]cinnoline 7 was obtained along with carbazole 4. Reaction of 2‐amino‐2′‐methoxybiphenyl 3d gave four products of carbazole 4,4‐hydroxycarbazole 6e, phenanthridine 8 and dibenzofuran 9. Reaction of 2‐aminodiphenylmethane 5a afforded acridine 10. In the case of 2‐aminobenzophenone 5b, acridone 11 was obtained as a major product. Reaction of 2‐aminobenzhydrol 5c gave acridine 10. When 2‐aminodiphenylamine 5d was reacted, phenazine 12 was obtained in good yield. In contrast, reaction of 2‐aminodiphenyl ether 5e produced only 2‐hydroxydiphenylamine 13. Reaction of 4‐aminophenanthrene 14 produced 4H‐benzo[def]carbazole 15 in 61% yield.     

Sensitive and high-throughput analyses of purine metabolites by dynamic pH junction multiplexed capillary electrophoresis: a new tool for metabolomic studies.

On-line sample preconcentration by a dynamic pH junction in conjunction with multiplexed capillary electrophoresis (CE) and UV detection represents a sensitive and high-throughput format for future metabolomic research, such as purine analysis. The optimization of purine focusing can be rapidly assessed by systematically altering the sample matrix properties, such as the buffer co-ion, pH and ionic strength using a 96-capillary array format. This method permits focusing of large sample injection volumes, resulting in over a 50-fold improvement in the concentration sensitivity. The limit of detection (S/N = 3) for purine metabolites was less than 8.0 x 10(-8) M under optimum conditions when using UV absorbance. Dynamic pH junction multiplexed CE demonstrated excellent linearity over a hundred-fold concentration range, as well as low inter-capillary precision in terms of normalized migration times and peak areas. The potential for clinically relevant high-throughput analyses of micromolar amounts of purine metabolites in urine was also demonstrated.     

Study on methane fermentation and production of vitamin B12 from alcohol waste slurry

We studied biogas fermentation from alcohol waste fluid to evaluate the anaerobic digestion process and the production of vitamin B₁₂ as a byproduct. Anaerobic digestion using acclimated methanogens was performed using the continuously stirred tank reactor (CSTR) and fixed-bed reactor packed with rock wool as carrier material at 55°C. We also studied the effects of metal ions added to the culture broth on methane and vitamin B₁₂ formation. Vitamin B₁₂ production was 2.92 mg/L in the broth of the fixed-bed reactor, twice that of the CSTR. The optimum concentrations of trace metal ions added to the culture liquid for methane and vitamin B₁₂ production were 1.0 and 8 mL/L for the CSTR and fixed-bed reactor, respectively. Furthermore, an effective method for extracting and purifying vitamin B₁₂ from digested fluid was developed.