63521-95-9Relevant academic research and scientific papers
A sulfoxide-based ring annelation approach to fused, many-membered ring N,S-heterocycles
Bates, Dallas K.,Xia, Mingde
, p. 9190 - 9196 (1998)
An approach to many-membered ring N,S-heterocycles involving sulfoxide electrophilic sulfenylation (SES) followed by ring expansion of the derived sulfonium salt intermediate (in situ) is illustrated for 9- and 10-membered- ring compounds. Treatment of readily prepared sulfoxides 10a, 10b, 18a, 18b, 23a, and 23b with triflic anhydride (pyridine, CH2Cl2, 0 °C) provides heterocycles 13a (65%), 13b (60%), 19a (67%), 19b (67%), 24a (42%), and 24b (80%), respectively. Sulfoxides 5a and 5b, under several different conditions, give only the Pummerer dehydration products 6a and 6b, respectively. Diastereomeric sulfoxides 18a' and 18b', upon treatment with triflic anhydride, do not produce clean product mixtures or any of the desired heterocyclic products but, upon heating in toluene, are converted to the more stable isomers 18a and 18b, respectively. Conducting this isomerization in the presence of 2-mercaptobenzothiazole produces a disulfide indicative of the intermediacy of a sulfenic acid. However, the importance of sulfenic acid derivatives in the SES process leading to many-membered ring heterocycles remains to be determined.
NOVEL DISUBSTITUTED 3,4-DIAMINO-3-CYCLOBUTENE-1,2-DIONE COMPOUNDS FOR USE IN THE TREATMENT OF CHEMOKINE-MEDIATED DISEASES
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Paragraph 0113, (2014/10/16)
Disubstituted 3,4-diamino-3-cyclobutene-1,2-dione compounds are described that correspond to general formula (I). Also described, are pharmaceutical compositions that include these compounds and methods of using these compounds and compositions for the tr
Process for the preparation of optically active carboxylic acids and amide intermediates
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, (2008/06/13)
The present invention provides a process for the preparation of optically active carboxylic acids of the formula I* or II* STR1 in which X is an oxygen or sulfur atom and n is 1 or 2. The process comprises reacting a racemic carboxylic acid I or II or its derivatives with an optically active 2-amino-carboxylic acid ester to give the diastereomeric carboxylic acid amides, separating the diastereomers and, after cleavage of the amide bond, isolating the optically active carboxylic acids of the general formula I* or II*. The invention also provides certain novel optically active carboxylic acid amides and a tetrahydrothiopyran-2-carboxylic acid.
A Porphyrin bearing Tetrahydrothiophene Pickets; Co-ordination Behaviour and Electron Transfer
D'Souza, Francis,Krishnan, Varadachari
, p. 2873 - 2876 (2007/10/02)
A novel 'picket-fence' porphyrin, 5,10,15,20-tetrakisporphyrin (H2L) with ligating tetrahydrothiophene rings disposed perpendicular to the porphyrin plane has been synthesised.Its zinc(II) derivative, , binds two silver(I) ions co-operatively with a dissociation constant of 4.8 x 10-8 dm3 mol-1.Time-resolved fluorescence lifetime measurements reveal the presence of intramolecular photoexcited electron transfer in this donor-acceptor system.
Spiro Derivatives of Tetrahydrothiophene. Synthesis of the Quinolizidinetetrahydrothiophene System Using Solid/Liquid or Liquid/Liquid Phase-Transfer Catalysis
Wrobel, Jerzy T.,Hejchman, Elzbieta
, p. 452 - 455 (2007/10/02)
4-Oxooctahydroquinolizinetetrahydrothiophene 1',1'-dioxide can be synthetized from 2-cyanotetrahydrothiophene by two independent routes, both of them using phase-transfer catalysis: the first one involves alkylation of 2-cyanotetrahydrothiphen
5-Fluorouracil derivatives, and their pharmaceutical compositions
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, (2008/06/13)
A compound of the formula: STR1 wherein R is a bridged alicyclic group selected from the group consisting of norbornyl, norbornenyl, bicyclo[2,2,2]-heptyl and adamantyl optionally substituted by at least one substituent selected from the group consisting
