Five new 1-hydroxy-2-(1-alkyloxymethyl)-9,10-Anthraquinones (9a-e) have been prepared. Selective nitration of 2-methyl-9,10-anthraquinone, reduction to the corresponding amine, diazotization and treatment by sulfuric acid solution afforded the 1-hydroxy-2-methyl-9,10-anthraquinone in good yield as the key intermediate. Reaction with dimethylsulphate/K2CO3 and subsequen...

Novel 9alpha and 9beta-hydroxy grayanotoxin II derivatives were prepared by photo-sensitized oxygenation of iso-grayanotoxin II and oxidation of grayanotoxin II tetraacetate with selenium dioxide respectively. The lethal dosage of 9alpha and 9beta-hydroxy grayanotoxin II were lower than that of grayanotoxin II. In addition, the lethal dosage of 9beta-hydroxy-dihydro grayanotoxin II was higher t...

The four stereoisomers of the 2-hydroxy derivatives of digitoxigenin and 3-epidigitoxigenin have been synthesized, their structures established by NMR, and their binding affinity for the digitalis receptor on Na+, K(+)-ATPase evaluated. These derivatives showed lower affinities than the parent compounds. The hydrophilic hydroxy groups in the alpha position are more detrimental to the affinity t...

Investigation of allelopathic substances from herbal plants may lead to the development allelochemical-based natural herbicides. Croton oblongifolius (Roxb.) is a well-known plant with long history being used for traditional medicines and source diverse range bioactive compounds. This has been reported have potential; however, its allelopathic-related not yet described. Therefore, we conducted ...

In the title compound, C(16)H(23)NO(5), the H-N-O-C torsion angle is 98.6 (1)°, which is of a similar magnitude to other N,O-diacyl-hydroxy-lamines. The N-O distance is 1.4029 (14) Å, which is similar to the N-O distance in other N,O-diacyl-hydroxy-lamines. In the crystal, intermolecular N-H⋯O hydrogen bonds generate chains of molecules.

A new chemo-enzymatic route to both isomers of 2-hydroxy-4-phenylbutyric acid is reported. The key step is the lactonase-catalyzed hydrolysis of cis- and trans-2-hydroxy-4-phenyl-4-butyrolactones followed by hydrogenation over Pd/C to afford optically pure 2-hydroxy-4-phenylbutyric acid.

Enantiopure β-hydroxy sulfoxides and catechol sulfoxides were obtained, by chemoenzymatic synthesis, involving dioxygenase-catalysed benzylic hydroxylation or arene cis-dihydroxylation and cis-diol dehydrogenase-catalysed dehydrogenation. Absolute configurations of chiral hydroxy sulfoxides were determined by X-ray crystallography, ECD spectroscopy and stereochemical correlation. The applicatio...

(-)-alpha-Pinene (1), a major constituent of many aromatic plants was biotransformed by the plant pathogenic fungus, Botrytis cinerea to afford three new metabolites, characterized as 3beta-hydroxy-(-)-beta-pinene (10%) (3), 9-hydroxy-(-)-a-pinene (12%) (4), 4beta-hydroxy-(-)-alpha-pinene-6-one (16%) (5) by physical and spectroscopic methods. A known metabolite verbenone (2) was also obtained.

N-Hydroxy-T-fluoro^-acetylaminofluorene (A^-hydroxy-7fluoro-AAF) and Ar-hydroxy-2-acetylaminophenanthrene (A7hydroxy-AAP) were identified as urinary metabolites of 7-fluoro2-acetylaminofluorene and 2-acetylaminophenanthrene, respectively, in the rat. When administered as 0.010-0.012% of the diet for 10-15 weeks AT-hydroxy-7-fluoro-AAF proved to be a much more potent carcinogen for the rat than ...

DT-diaphorase catalysed the reduction of 1,4-naphthoquinones with hydroxy, methyl, methoxy and glutathionyl substituents at the expense of reducing equivalents from NADPH. The initial rates of quinone reduction did not correlate with either the half-wave reduction potential (E1/2) value (determined by h.p.l.c. with electrochemical detection against an Ag/AgCl reference electrode) or the partiti...