25027-38-7Relevant academic research and scientific papers
Chemistry of Novel Compounds with Multifunctional Carbon Structure. 9. Molecular Design, Synthetic Studies, and NMR Investigation of Several Efficient Chiral Derivatizing Reagents which Give Very Large (19)F NMR Δδ Values in Enantiomeric Excess Determination
Takeuchi, Yoshio,Itoh, Noriaki,Satoh, Toshihiro,Koizumi, Toru,Yamaguchi, Kentaro
, p. 1812 - 1820 (1993)
In order to develop efficient ee-determining reagents potentially superior to MTPA (1), some multifunctional compounds 2-5 were rationally designed.From NMR investigations of the analogous diastereomeric derivatives it was found that the chemical shift differences for each pair of diastereomers (Δδ values) for CFPA derivatives 5d-f were approximately five times greater in (19)F NMR spectra and two times greater in 1H NMR spectra than those of 1d-f.Synthesis of the optically pure CFPA, (-)-5a nd (+)-5a, was achieved by nitrosation of each diasteromer of the optically active N-(1-phenylethyl)amides, 5fM and 5fL, followed by thermal decomposition.Various derivatives were prepared by the condensation of 5b and 1b with alcohol and amine nucleophiles, and both ΔδF and ΔδH values were obtained for each compound.The CFPA derivatives 5d-m have proven to be significantly superior for ee determinations when compared to the corresponding MTPA derivatives 1d-m, particularly in compounds having remotely disposed chiral centers.
Design and synthesis of new 8-anilide theophylline derivatives as bronchodilators and antibacterial agents
Hayallah, Alaa M.,Talhouni, Ahmad A.,Abdel Alim, Abdel Alim M.
, p. 1355 - 1368 (2013/01/15)
Theophylline derivatives have long been recognized as potent bronchodilators for the relief of acute asthma. Recently, it was found that bacterial infection has a role in asthma pathogenesis. The present work involves the design and synthesis of 8-substituted theophylline derivatives as bronchodilators and antibacterial agents. The chemical structures of these compounds were elucidated by IR, 1H-NMR, mass spectrometry, and elemental analyses. The bronchodilator activity was evaluated using acetylcholine-induced bronchospasm in guinea pigs, and most of the compounds showed significant anti-bronchoconstrictive activity in comparison with standard aminophylline. In addition, the antibacterial activity of all the target compounds was investigated in vitro against Gram-positive and Gram-negative bacteria using ampicillin as a reference drug. Results showed that some of the tested compounds possessed significant antibacterial activity. A pharmacophore model was computed to obtain useful insight into the essential structural features of bronchodilator activity. A structure activity relationship was also discussed.
