Results 281 to 290 of about 3,016,957 (322)

Cannabis XXII. Synthesis of spiro-compounds

Tetrahedron Letters, 1981
Abstract O-methyl-cannabispirenone has been synthesized by two new methods applying spiroannelation on 5,7-dimethoxyindan-1-aldehyde. An alternative high yield synthesis of the latter has been elaborated.
Jiří Novák, Cornelis A. Salemink
openaire   +2 more sources

Spiro Bicyclic Guanidino Compounds from Pufferfish: Possible Biosynthetic Intermediates of Tetrodotoxin in Marine Environments.

Chemistry, 2018
Tetrodotoxin (TTX, 1) is a potent neurotoxin that is widely found in both terrestrial and marine animals; however, the biosynthetic pathway and genes for TTX have not yet been elucidated.
Nozomi Ueyama, K. Sugimoto, Y. Kudo, Ken-ichi Onodera, Yuko Cho, K. Konoki, T. Nishikawa, M. Yotsu-Yamashita   +7 more
semanticscholar   +1 more source

The catalytic asymmetric synthesis of CF3-containing spiro-oxindole-pyrrolidine-pyrazolone compounds through squaramide-catalyzed 1,3-dipolar cycloaddition.

Organic and biomolecular chemistry, 2019
Pharmaceutically important compounds were synthesized through the organocatalytic 1,3-dipolar cycloaddition reaction. In the presence of a cinchonine-derived squaramide catalyst, the cycloaddition of N-2,2,2-trifluoroethylisatin ketimines with α,β ...
Cuie Wang, Dongwa Wen, Hui Chen, Yabo Deng, Xueting Liu, Xin Liu, Li Wang, Fengyun Gao, Yifei Guo, Mengmeng Sun, Kairong Wang, Wenjin Yan   +11 more
semanticscholar   +1 more source

The Quinary Catalyst-Substrate Complex Induced Construction of Spiro-Bridged or Cagelike Polyheterocyclic Compounds via a Substrate-Controlled Cascade Process.

Organic Letters, 2019
The asymmetric organocatalytic cascade reaction of cyclic β-oxo aldehydes to 2-hydroxycinnamaldehydes is developed. The bifunctional tertiary amine-thiourea catalyst was used in a rationally designed multiple catalysis where the asymmetric iminium ...
Chen Wang, Yinghan Chen, Hui-Chun Wu, Cong Wang, Yan-Kai Liu   +4 more
semanticscholar   +1 more source

Ring strain energy in ether‐ and lactone‐containing spiro compounds

, 2015
Ring strain energies (RSEs) have been calculated for oxygen-containing spiro compounds using the group equivalent reaction (GER) formalism. The RSEs for all compounds studied were calculated from the energies of fully-optimized structures at the MP2 ...
Matthew K. Stedjan, J. D. Augspurger
semanticscholar   +1 more source

Organocatalytic Asymmetric Synthesis of Spiro-Bridged and Spiro-Fused Heterocyclic Compounds Containing Chromane, Indole, and Oxindole Moieties.

Organic Letters, 2018
Following the reactivity inversion strategy, two different two-step sequences were designed and successfully applied to the asymmetric synthesis of spiro-bridged and spiro-fused heterocyclic compounds, which combined chromane, indole, and oxindole, three
Zhi-Hao You, Yinghan Chen, Yu Tang, Yan-Kai Liu   +3 more
semanticscholar   +1 more source

Phosphorus–nitrogen compounds. Part 42. The comparative syntheses of 2-cis-4-ansa(N/O) and spiro(N/O) cyclotetraphosphazene derivatives: spectroscopic and crystallographic characterization, antituberculosis and cytotoxic activity studies

New Journal of Chemistry, 2019
Syntheses, structural properties and biological activities of ferrocenyl ansa- and spiro-cyclotetraphosphazenes were investigated.
Arzu Binici, Aytuğ Okumuş, Gamze Elmas, Z. Kılıç, Nagehan Ramazanoğlu, L. Açık, H. Simsek, B. Çağdaş Tunalı, M. Türk, Remziye Güzel, T. Hökelek   +10 more
semanticscholar   +1 more source

Synthesis of Tricyclic Spiro Compounds on the Basis of Alloocimene.

ChemInform, 2005
AbstractFor Abstract see ChemInform Abstract in Full Text.
M. S. Mitkova, E. Kh. Balbolov, M. Ya. Skumov   +2 more
openaire   +3 more sources

Electronic properties of spiro compounds for organic electronics

The Journal of Chemical Physics, 2012
The electronic properties of p-type, n-type, and ambipolar spiro materials have been investigated using a combination of photoemission spectroscopy, electron energy-loss spectroscopy, and density functional based calculations. Our results provide insight into the occupied density of states as well as the electronic excitation spectra.
Torsten Hahn, Mandy Grobosch, Benjamin Mahns, Susi Lindner, Josef Salbeck, Thomas Reichert, Martin Knupfer, Friedrich Roth, Tobat P. I. Saragi   +8 more
openaire   +3 more sources

Extension and revision of the nomenclature for spiro compounds [PDF]

Pure and Applied Chemistry, 1999
Abstract Spiro ring systems have two or more rings linked by one common atom. Several different methods are used to name such systems. Rules A-41, A-43, B-10 and B-12 (Nomenclature of Organic Chemistry, 1979) describe the basics of how to name these compounds.
openaire   +1 more source