Besi merupakan unsur yang penting bagi proses metabolisme organisma seperti kitar asid trikarboksilik, pengangkutan elektron dan fosforilasi oksidatif. Walau bagaimanapun, sumber besi di persekitaran luar sentiasa berada dalam bentuk kompleks tidak tersedia untuk pengambilan terus. Bagi mengatasi pengehadan besi, mikroorganisma berupaya menghasilkan siderofor, sejenis pengkelat Fe(III) berafina...

The recently discovered organic cofactor of bovine serum amine oxidase, topa quinone, is an uncommon amino acid residue in the polypeptide backbone (Janes, S. M., Mu, D., Wemmer, D., Smith, A. J., Kaur, S., Maltby, D., Burlingame, A. L., and Klinman, J. P. (1990) Science 248, 981-987). The amine oxidase gene from the yeast Hansenula polymorpha has been cloned and sequenced (Bruinenberg, P. G., ...

The complexation of a tweezers ligand with zinc perchlorate in the absence and presence of amines in methanol solution was explored. L(2)Zn(2)(ClO(4))(4) was a thermodynamic product of the reaction in the absence of an amine. The complex was shown to interact with aliphatic amines resulting in the formation of a Zn-N(amine) bond. If metal-ligand complexation was carried out in the presence of a...

Previous studies have shown that when Staphylococcus aureus becomes resistant to sulfonamides, an antisulfonamide substance is produced in the growth medium. Although these studies suggested that the substance was p-aminobenzoic acid (PABA), isolation and positive identification were not achieved. Because of the importance of these observations, unequivocal identification of the product was att...

Reduction of imines by [2,5-Ph2-3,4-Tol2(eta(5)-C4COH)]Ru(CO)2H (2) produces kinetically stable ruthenium amine complexes. Reduction of an imine by 2 in the presence of an external amine trap gives only the complex of the newly generated amine. Reaction of 2 with H2N-p-C6H4N=CHPh (11), which contains an intramolecular amine trap, gave a 1:1 mixture of [2,5-Ph2-3,4-Tol2(eta(4)-C4CO)](CO)2RuNH(CH...

1. Inactivation of beta-phenylethylamine and several of its derivatives was studied in a preparation of rabbit lung perfused with Krebs physiological medium at 37 degrees C. Inactivation or removal of these compounds was calculated as the difference between the concentration of each amine in the perfusion medium and the effluent, collected separately from each lung. The extent of amine metaboli...

Aliphatic amines, such as n-hexylamine (primary), di-n-hexylamine (secondary) and tri-n-hexylamine (tertiary amine), react with tetrabromophenolphthalein ethyl ester molecules (TBPEH) to form reddish or red-violet charge-transfer complexes (CT complexes) in 1,2-dichloroethane (DCE). The absorption maxima of the CT complexes with all primary amines occur at around 560 nm, with secondary amines a...

N-Acetylation of (2,3,4,6-tetra-O-acetyl-a-D-glucopyranosyl) (2,3,4,6-tetra-0-acetyl-/?-D-glucopyranosyl)amine or bis(2,3,4,6-tetra-0-acetyl-/3-D-glucopyranosyl)amine afforded N-acetyl-bis(2,3, 4,6-tetra-0-acetyl-/3-D-glucopyranosyl)amine; deacetylation of the latter gave Af-acetyl-di-/3-Dglucopyranosylamine. Similarly, TV-acetylation of bis(2,3,4-tri-0-acetyl-/3-L-rhamnopyranosyl)amine led to ...

A series of N-benzylidenepyridin-2-amines (1a-j) were synthesized by heating 2-aminopyridine with different substituted aromatic aldehydes in the presence of toluene. The structures of the synthesized compounds were confirmed on the basis of IR, 1H NMR, 13C NMR and mass spectral data. The compounds 1a-j were screened for anthelmintic activity. Test results revealed that the compounds showed par...