共查询到20条相似文献,搜索用时 15 毫秒
1.
All four isomers of substituted 3-alkylthio-4-hydroxybutenes have been synthesised: both the geometry of the double bond and the relative stereochemistry of the two chiral centres are controlled. 相似文献
2.
3.
4.
Hiroyuki Kikuchi Yasumasa Tsukitani Yasuji Yamada Kazuo Iguchi Steven A. Drexler Jon Clardy 《Tetrahedron letters》1982,23(10):1063-1066
The structure and absolute stereochemistry of lemnalol (1), a new ylangene-type sesquiterpenoid isolated from the soft coral Verseveldt, has been established by spectroscopic, chemical, and x-ray crystallographic analyses. 相似文献
5.
6.
Chemical correlation studies and application of Horeau's method establish the absolute stereochemistry of the major cadinene from . as shown in {=1}. 相似文献
7.
Toshihiro Hashimoto Motoo Tori Zenei Taira Yoshinori Asakawa 《Tetrahedron letters》1985,26(52):6473-6476
Four novel fusicoccane diterpenoids, fusicoplagins A, B, C, and D, have been isolated from the liverwort subsp. and the structures determined by spectroscopic methods, chemical transformations, and X-ray crystallographic analysis. 相似文献
8.
N-Acyl derivatives of ,-acosamine and ,-ristosamine were synthesized with high stereo selectivity utilizing intramolecular Michael addition of γ- and δ-carbomoyloxy-α,β-unsaturated esters. 相似文献
9.
10.
J Leitich 《Tetrahedron letters》1980,21(32):3025-3028
The relative rates of formation of and [2+2]cycloadducts of benzyne to , - and , -1,5-cyclooctadiene, - and -cyclooctene are discussed and properties of the adducts (e.g., their unusual hydrogenation) are described. 相似文献
11.
Richard R. Izac Steven E. Poet William Fenical Donna Van Engen Jon Clardy 《Tetrahedron letters》1982,23(37):3743-3746
An ichthyotoxic sesquiterpenoid of unusual structure, pacifigorgiol, has been isolated from the Pacific gorgonian caora . The structure of pacifigorgiol, with relative stereochemistry only, has been defined by a combination of spectral and x-ray crystallographic techniques. 相似文献
12.
13.
Stephen W. Ayer Jocelyne Hellou Mark Tischler Raymond J. Andersen 《Tetrahedron letters》1984,25(2):141-144
Extracts of the dorid nudibranch contain the sesquiterpene nanaimoal (1). The structure of nanaimoal was inferred from its spectral data and the biogenetic isoprene rule. it was confirmed by an unambiguous synthesis of its p-bromophenyl-urethane derivative 10. 相似文献
14.
15.
16.
17.
18.
19.
20.
Reaction of Ga(CH3)3 with N,N′-dimethyloxamide affords two isomeric N,N′-bis(dimethylgallium)-N,N′-dimethyloxamide complexes, characterized by crystal structure analysis as having cis-and trans-configuration with respect to the central oxamide CC bond and belonging to the point groups C2v (cis) and C2h (trans), respectively. Both isomers which are formed in varying ratio, depending upon the reaction conditions, have been isolated in pure form; their vibration spectra (IR/RE) are analyzed in detail in points of alternative behaviour, and are assigned in all bands, especially in the G-C and Ga-X frequency region. The assignment receives further confirmation from a comparison with the vibrational data of the homologous N,N′-bis(dimethylgallium)oxamide (cis/trans isomer mixture). 相似文献