Tumor necrosis factor is one of the important cell factors,which can regulate pro-imflammatory.On the basis of the known and efficient peptidomimetic inhibitors of tumor necrosis factor as the leading compounds,novel sulfur-containing peptidomimetic inhibitors were designed and synthesized in a convenient and efficient manner.Bioassay results indicate that three of them showed some inhibition activity on sTNF-α secretion in HL-60 cells induced by lipolysaccharide,and two of them showed a good stability and inhibition activity.
The mass spectrometric fragmentation of ( S, S) -N, N'-bis [ 1- (hydroxymethyl) alkyl] anthracene/naphthalene-1, 8-dicarboxamides was investigated with the aid of mass-analyzed ion kinetic energy spectrometry and the elemental compositions of important fragment ions were determined by accurate mass measurement under electron impact ionization conditions. All the compounds could eliminate formaldehyde. The [ M-CH2O] ions could also eliminate imine, aziridine, aziridinone, 2-amonoalkan-1-ol, water, and other fragments. Several cyclizations were observed under electron impact ionization.
The mass spectrometric fragmentation of 1-(benzyloxycarbonyl)amino-2-alkyl/cycloalkyl thioacetates has been studied with the aid of mass-analysed ion kinetic energy spectrometry under electron impact ionization. All compounds show a tendency to eliminate a ketene, thioacetic acid, and benzyl carbamate molecule, or an acetyl and benzyloxy radicals. A thioester pyrolysis-type rearrangement under electron impact ionizations was observed.
The reactions of 2,3-dihydro-1,5-benzothiazepines with ethoxyearbonylcarbene undergo complex rearrangements to produce rlng-opening and ring contraction products. Previously it was presumed that the different products were formed via different mechanisms depending on the kind of substituents at the 2-position of 1,5-benzothiazepines. However, on the basis of the further detailed investigation, it was found that all 1,5-benzothiazepines can undergo the same rearrangement to yield both ring-opening and ring contraction products.
A series of alkyl 4-dialkylaminophenyl ketones were prepared and reduced asymmetrically by borane under the chiral oxazaborolidine catalysis. The results indicate that the ketones show a more obvious subsfituent effect on the enanfioselectivity than the corresponding 4-alkyl/alkoxy/alkylthiophenyl ketones in the asymmetric reduction because of the existence of a strong coordinate nitrogen atom with the boron atom in the catalyst and borane.