Results 251 to 260 of about 121,287 (309)

Scholl Cyclizations of Aryl Naphthalenes: Rearrangement Precedes Cyclization

The Journal of Organic Chemistry, 2015
In 1910, Scholl, Seer, and Weitzenbock reported the AlCl3-catalyzed cyclization of 1,1'-binaphthyl to perylene. We provide evidence that this classic organic name reaction proceeds through sequential and reversible formation of 1,2'- and 2,2'-binaphthyl isomers.
Sarah L, Skraba-Joiner, Erin C, McLaughlin, Aida, Ajaz, Rajesh, Thamatam, Richard P, Johnson   +4 more
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The cyclization of peptides and depsipeptides

Journal of Peptide Science, 2003
AbstractConstricting the peptide backbone into a more defined conformational form through cyclization is an activity evolved in nature and in synthetic work, the latter straddling only the most recent decades. The resulting conformational constraints increase the probability of an optimum response with bio‐receptors.
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Cyclization in Opioid Peptides

Current Drug Targets, 2013
Endogenous opioid peptides have been studied extensively as potential therapeutics for the treatment of pain. The major problems of using natural opioid peptides as drug candidates are their poor receptor specificity, metabolic instability and inability to reach the brain after systemic administration.
Justyna, Piekielna, Renata, Perlikowska, Katarzyna, Gach, Anna, Janecka   +3 more
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Biomimetic polyene cyclizations

Bioorganic Chemistry, 1976
AbstractCertain polyenic substances having trans olefinic bonds in a 1,5 relationship can be induced to undergo stereospecific, non‐enzymic, cationic cyclization to give polycyclic products with all‐trans (“natural”) configuration. These transformations appear to mimic in principle the biogenetic conversion of squalene into polycyclic triterpenoids ...
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The cyclization of natural rubber

Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1963
Abstract Several methods of measuring the unsaturation remaining in natural rubber after cyclization have been compared. Approximate agreem ent was obtained with the reagents, perbenzoic acid, phenyl iododichloride and ozone; iodine chloride gave high values. Perbenzoicacid is considered the most satisfactory of these reagents.
D. F. Lee, J. Scanlan, W. F. Watson
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Enantioselective polyene cyclizations

Organic & Biomolecular Chemistry, 2016
A comprehensive review covering the field of enantioselective polyene cyclizations.
Chad N, Ungarean, Emma H, Southgate, David, Sarlah   +2 more
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Stereoselective Electrophilic Cyclization

The Chemical Record, 2015
AbstractElectrophilic cyclizations of unactivated alkenes play highly important roles in the synthesis of useful building blocks. This account describes our contributions to the rational design of monofunctionalized chiral Lewis base catalysts for enantioselective iodo‐ and protocyclizations.
Akira, Sakakura, Kazuaki, Ishihara
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Cyclization Reactions of Methylthioacetanilides.

ChemInform, 2003
AbstractFor Abstract see ChemInform Abstract in Full Text.
Yu-Jen Liao, Yi-Lung Wu, Che-Ping Chuang
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Cyclo‐ and cyclized diene polymers. VIII. Cyclization of polybutadienes and ir spectra of cyclized polybutadiene

Journal of Polymer Science Part C: Polymer Symposia, 1967
AbstractCyclization of cis‐1, 4 and trans‐1, 4‐polybutadiene as of poly (2,3‐dimethyl butadiene‐1,3) was carried out with H2S4 as the cyclization agent. The decrease of the original unsaturation as well as of total unsaturation were measured with IR spectroscopy and the iodine monochloride method, respectively. The kinetics of cyclization were measured
I. Kössler, J. Vodehnal, M. Štolka, J. Kálal, E. Hartlová   +4 more
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Acid-Catalyzed Cyclization of Epoxyallylsilanes. An Unusual Rearrangement Cyclization Process

Organic Letters, 2003
[reaction: see text]. A new route for the synthesis of epoxyallylsilanes bearing the phenyldimethylsilyl group is reported that involves silylcupration of allene, conjugate addition to enones, and sulfur-ylide-mediated epoxidation. The Lewis acid-catalyzed cyclization of these substrates is presented. The expected normal products derived from 5-exo and/
Asunción, Barbero, Pilar, Castreño, Francisco J, Pulido   +2 more
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