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11.
Some o-xylylene (o-quinodimethane) derivatives were isolated as stable cyrstalline materials. A strong through-bond interaction in tetracyanoethylene addition product of tetraphenylbenzodicyclobutadiene ( is suggested. 相似文献
12.
13.
Hiroshi Saito Hitoshi Kurabe Eiichi Suzuki Fumio Watari 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》1995,51(14)
The IR spectra (4000-250 cm−1) of CH3SCl and CD3SCl in solid argon have been obtained. Fundamental vibrations, except the torsional vibrations, have been assigned. Normal coordinate analysis has been carried out omitting the torsional modes. 相似文献
14.
Masatoshi Sakae Masanori Katsurada Mayumi Watanabe Fumio Yoneda Sadao Nishigaki Toshimasa Ishida 《Journal of heterocyclic chemistry》1997,34(1):157-160
The reaction of 2-bromoethylamine 1 with methylisothiocyanate 2 under mild condition gave 2-methyl-amino-2-thiazoline 3 as the major product together with two kinds of byproducts, 3-(N-methylthiocar-bamoyl)-2-methyliminothiazolidine 4 and N,N′-dimethyl-N-(2-thiazolin-2-yl)thiourea 5. Thermal isomer-ization of 5 to 4 was observed. The structures of the byproducts were confirmed by X-ray crystallography. 相似文献
15.
Seiji Miyano Osamu Yamashita Kunihiro Sumoto Keiyu Shima Mariko Hayashimatsu Fumio Satoh 《Journal of heterocyclic chemistry》1987,24(1):271-274
The method for preparing 7a-substituted hexahydro-1H-pyrrolizines 2 from 1,2,3,5,6,7-hexahydropyrrol-izinium Perchlorate (3) was investigated, by which introduction of a wide variety of functionalities on C(7a) could be achieved easily. 相似文献
16.
This review covers newly isolated simple indole alkaloids, structure determinations, total syntheses and biological activities reported in the literature in 2003. 相似文献
17.
Sano S Takehisa T Ogawa S Yokoyama K Nagao Y 《Chemical & pharmaceutical bulletin》2002,50(9):1300-1302
Tetrasubstituted (Z)-alkenes were readily prepared through the Horner-Wadsworth-Emmons reactions of methyl 2-[bis(2,2,2-trifluoroethyl)phosphono]propionate with aryl alkyl ketones by employing Sn(OSO(2)CF(3))(2) and N-ethylpiperidine. 相似文献
18.
Fumio Watari J. Van Landuyt P. Delavignette S. Amelinckx 《Journal of solid state chemistry》1979,29(1):137-150
A study by means of electron microscopy at high resolution has enabled the analysis of the microstructure of hematite as produced by dehydration from goethite. The apparently “polycrystalline” structure is found to consist of aggregates of well-oriented twin-related hematite crystals, separated by regularly spaced H(001) walls of voids resulting from the loss of water. The material is thus broken up into blocks with sizes smaller than 50 Å. The crystallography of the twinned structure can be analyzed by electron diffraction data and dark-field imaging. These aggregates of hematite crystals provide an ideal mosaic structure. In particular the effect of this mosaic structure on the individual reflections of the diffraction patterns has been analyzed and discussed. 相似文献
19.
Kashiwada Y Chiyo J Ikeshiro Y Nagao T Okabe H Cosentino LM Fowke K Morris-Natschke SL Lee KH 《Chemical & pharmaceutical bulletin》2000,48(9):1387-1390
3-Alkylamido-3-deoxy-betulinic acids were synthesized and evaluated for anti-HIV activity as part of the structure-activity relationship study of the potent anti-HIV agent 3-O-(3',3'-dimethyl)-succinyl-betulinic acid (DSB) (2). 3Alpha-diglycorylamide-3-deoxy-betulinic acid demonstrated relatively potent anti-HIV activity (EC50 0.24 microm, TI 728). However, replacing the ester group at C-3 in 2 and its analogues with an amido group yielded inactive or much less potent compounds against HIV replication, indicating that the ester group at C-3 in 2-4 is essential for potent anti-HIV activity. 相似文献
20.
X-ray analysis of the title complex revealed hydrogen-bonded chains comprising two crystallographically independent types of -9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene molecules, in which the central 1,4-cyclohexadiene rings are respectively flat and very slightly puckered, with the ethanol molecules attached exclusively to the latter type. 相似文献