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31.
Sbin-Ichi Nagai Taisei Ueda Akito Nagatsu Keiko Nakaoka Nobutoshi Murakami Jinsaku Sakakibara Michiko Fujita Yoshihiro Hotta 《Journal of heterocyclic chemistry》1998,35(2):329-332
5,8-Methanoquinazolines fused with imidazoles 4a-4b , thiadiazoles 5–6 , pyrimidines 7, 9, 11 and 12 , and 1,3,5-triazine 13 were prepared starting from (5R,8S)-2-amino-8,9,9-trimethyl-5,6,7,8-tetrahydro-5,8-methanoquinazoline 3 . Most compounds possessed central nervous system stimulant activities. 相似文献
32.
Chisuzu Tokoh Keiji Takabe Minoru Fujita Hiroshi Saiki 《Cellulose (London, England)》1998,5(4):249-261
Acetobacter xylinum was cultured in Hestrin-Schramm medium (control medium) and Hestrin-Schramm medium containing acetyl glucomannan (mannan medium). Loose bundles of the cellulose microfibrils are formed in the mannan medium in contrast to the normal ribbons being produced in the control medium. Rapid-freeze and substitution method followed by metal-shadowing revealed the droplet-like structures around the microfibril synthesized in the mannan medium. The cellulose synthesized in the mannan medium was stained heavily by the periodic acid-thiocarbohydrazide-silver proteinate (PATAg) method, while the cellulose synthesized in the control medium was not stained. X-ray diffractometry and FT-IR spectroscopy indicated that the addition of mannan induced a change in the crystal structure from the algal-bacterial type to the cotton-ramie type. Thus the presence of acetyl glucomannan in the medium prevents the assembly of cellulose microfibrils and changes the crystal structure of cellulose. 相似文献
33.
Spectrophotometric determinations of palladium(II) and tartaric acid were respectively investigated by using the color reactions between 2(5-nitro-2-pyridylazo)-5-(N-propyl-N-3-sulfopropylamino)phenol(5-NO2.PAPS) and palladium(II) in strong acidic media, and between 5-NO2.PAPS, niobium(V) tartaric acid in weak acidic media. The calibration graphs were linear in the range of 0–25 μg/10 ml palladium(II), with an apparent molecular coefficient () of 6.2×104 l mol−1 cm−1 at 612 nm, and 0–23 μg/10 ml tartaric acid with =1.08×106 l mol−1 cm−1 at 612 nm, respectively. The proposed methods were selective and sensitive in comparison with other chelating pyridylazo dyes–palladium(II) or metavanadic acid–tartaric acid method, and the effect of foreign ions such as copper(II) was negligible for the assay of palladium(II) with 5-NO2.PAPS. 相似文献
34.
Alkyl phenylsulfinates (Ph-SO-OR) were prepared from thiophenol (or diphenyldisulfide) by electrolysis in acetic acid with alcohols and sodium acetate in satisfactory yields. 相似文献
35.
36.
Itsuro Matsuo Muneo Ohkido Hitoshi Fujita Kenshi Suzuki 《Photochemistry and photobiology》1980,31(2):175-178
Abstract— When a suspension of Escherichia coli was irradiated with near-UV light in the presence of chlorpromazine (at a concentration below a cytotoxic level), the cells were killed. Efficiency of the photodynamic killing was not influenced by the deficiency of the uvrA gene or the recA gene. Neither phenotypic reversion of E. coli Hs30R (arginine auxotroph) nor induction of lambda prophage in lysogenic bacteria was detected after this treatment. 相似文献
37.
Total synthesis of codonocarpine () and its regio-isomer () utilizing a new cyclization procedure is described. 相似文献
38.
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40.
P. Meunier C. Blancpain F. R. Olson D. M. Hegstedt W. H. Peterson D. W. Bolin A. M. Khalapur A. Fujita T. Ebihara und Fr. Folkmann 《Fresenius' Journal of Analytical Chemistry》1942,124(1-2):68-69
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