Several proline derivatives such as L-azetidine-2-carboxylic acid, cis-4-hydroxy-L-proline, and 3,4-dehydro-DL-proline prevent procollagen from folding into a stable triple-helical conformation, thereby reducing excessive deposition of collagen in fibrotic processes and the growth of tumors. This study was performed to investigate whether the recently discovered human proton-coupled amino acid ...

Mycobacterium sp. strain KR20, which was isolated from a polycyclic aromatic hydrocarbon (PAH) contaminated soil of a former gaswork plant site, metabolized about 60% of the fluoranthene added (0.5 mg ml(-1)) to batch cultures in mineral salts medium within 10 d at 20 degrees C. It thereby increased its cell number about 30-fold and produced at least seven metabolites. Five metabolites, namely ...

In the title compound, C(12)H(13)ClO(4), the 1,3-dioxane ring adopts a chair conformation and the 2-chloro-benzene and methyl substituents occupy equatorial sites. The carboxyl group is in an axial inclination. In the crystal, carb-oxy-lic acid inversion dimers linked by pairs of O-H⋯O hydrogen bonds generate R(2) (2)(8) loops.

Four new compounds have been synthesized as potential inhibitors of dihydroorotase from Escherichia coli. NMR spectroscopy was used to show that 4,6-dioxo-piperidine-2(S)-carboxylic acid (3), exists in solution as a mixture of the hydrate (7), enol (8), and enolate (9) tautomeric forms. This compound was found to be a competitive inhibitor versus dihydroorotate and thio-dihydroorotate at pH val...

The yeast Trichosporon mucoides, grown on either glucose or phenol, was able to transform biphenyl into a variety of mono-, di-, and trihydroxylated derivatives hydroxylated on one or both aromatic rings. While some of these products accumulated in the supernatant as dead end products, the ortho-substituted dihydroxylated biphenyls were substrates for further oxidation and ring fission. These r...

The title compound, C(10)H(16)O(3), with a bicyclo-[3.1.1]heptane unit, was obtained by oxidation of β-pinene. The asymmetric unit contains two independent mol-ecules with similar geometry: the six-membered rings in both mol-ecules adopt envelope conformations. In the crystal, the independent mol-ecules exist as O-H⋯O hydrogen-bonded dimers. The dimers are linked into helical chains along the b...

The pterins xanthopterin (2-amino-4:6-dihydroxypteridine) (Koschara, 1936) and biopterin (2amino 4 hydroxy-6-[1: 2-dihydroxypropyl (L-erythro)]-pteridine) (Patterson, Saltza & Stokstad, 1956) have been isolated from human urine. It has been suggested that the pterins 2-amino-4-hydroxypteridine-6-carboxylic acid, 2-amino-4-hydroxypteridine and isoxanthopterin (2-amino-4:7-dihydroxypteridine) are...

aqueous polyurethane dispersions (puds) have recently emerged as important alternatives to their solvent-based counterparts for various applications due to increasing health and environmental awareness (green chemistry). anionic polyester-polyurethane dispersions were synthesized by three steps. in the first step, macromonomer diisocyanate having carboxylic acid was prepared by isophorone diiso...