Results 141 to 150 of about 1,407 (189)

A New, Chiral Bis-Benzothiazine Ligand

Organic Letters, 2001
[reaction: see text]. The synthesis and application of a new, chiral bis-benzothiazine ligand are described.
M, Harmata, S K, Ghosh
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New benzoxazine and benzothiazine dyes

Tetrahedron, 1976
Abstract 2H-1,4-benzoxazine can be generated in situ from 1-(o-aminophenoxy)-2,2′-dimethoxyethane in trifluoroacetic acid whence further reaction leads to the benzoxazine bye 7. The benzothiazine dye 9 can be derived in similar fashion from 1-(o-aminophenylthio)-2,2-diethoxyethane.
F. Chioccara, G. Prota, R.H. Thomson
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Further Studies of Benzothiazine Metalation

Synthesis, 2013
Treatment of benzothiazines 3 and 8 with butyllithium resulted in deprotonation at C3 to afford the corresponding organolithium species. These compounds could be trapped with a variety of electrophiles to give products in high yield. Some limitations to the processes chiefly based on steric effects were uncovered.
Michael Harmata, Nathan Calkins
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1,3-Benzothiazines (review)

Chemistry of Heterocyclic Compounds, 1979
Data on the methods for the synthesis of 1,3-benzothiazines and their derivatives and their chemical properties and physiological activity are correlated.
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Photochemical ring contraction of dihydro-1,4-benzothiazines

Tetrahedron Letters, 1994
Abstract The pheomelanin precursor 1a and the related dihydro-1,4-benzothiazines 1b–f undergo ring contraction upon irradiation with pyrex-filtered UV light to give 2-methylbenzothiazoles 2a–f in good yields.
C. COSTANTINI, G. TESTA, CRESCENZI, ORLANDO, D'ISCHIA, MARCO   +3 more
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Benzothiazines in Synthesis. Formal Synthesis of Erogorgiaene.

ChemInform, 2005
A benzothiazine, readily available in enantiomerically pure form via a completely selective, intramolecular addition of a sulfoximine-stabilized carbanion to an α,β-unsaturated ester, could be converted to a precursor to erogorgiaene in good overall yield.
Michael Harmata, Xuechuan Hong
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ChemInform Abstract: 1,3‐BENZOTHIAZINES

Chemischer Informationsdienst, 1979
AbstractIn einer kurzen Zusammenfassung werden die Synthesen und chemischen Eigenschaften der 1,3‐Benzothiazine (I)‐(III) sowie ihrer Dihydro‐, Oxo‐ und Dioxoderivate erläutert.
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Reversible formation of cyclic 1,4‐benzothiazine oligomers

Journal of Heterocyclic Chemistry, 1987
Abstract1,4‐Benzothiazine 2, generated in situ by mild hydrolysis of aminoacetal 3, readily undergoes aldolization to give mainly two pairs of diastereoisomeric trimers and tetramers, having the gross structure 5 and 6 respectively. In strongly acidic media the oligomers are depolymerized to give monomeric 2H‐1,4‐benzothiazine (1H nmr evidence) which ...
F. CHIOCCARA, NOVELLINO, ETTORE
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The “Benzothiazine” Chromophore of Pheomelanins: A Reassessment^†

Photochemistry and Photobiology, 2007
AbstractThe characteristic absorption and photochemical properties of pheomelanins are generally attributed to “benzothiazine” structural units derived biogenetically from 5‐S‐cysteinyldopa. This notion, however, conveys little or no information about the structural chromophores responsible for the photoreactivity of pheomelanins.
NAPOLITANO, ALESSANDRA, DE LUCIA, MARIA, PANZELLA, LUCIA, D'ISCHIA, MARCO   +3 more
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ChemInform Abstract: Benzothiazines in Organic Synthesis. Stereoselectivity in the Intermolecular Michael Addition Reactions of Benzothiazines.

ChemInform, 2008
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Michael Harmata, Yugang Chen, Charles L. Barnes   +2 more
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