A simple isocratic reversed phase high performance liquid chromatography was used to separate three impurities present in the sample of 8-chlorotheophylline. LC-MS was used for the characterization of impurities. Based on mass spectral data, the structures of these impurities were characterized as 3,7-dihydro-1,3-dimethyl-1H-purine-2,6-dione (impurity I), 3,7-dihydro-1,3,7-trimethyl-1H-purine-2...

We report here a simple entry into naphtho[2,3-d]isoxazole-4,9-dione system containing a EWG in position 3 using the readily available 2,3-dichloro-1,4-naphthoquinone and nitromethyl derivatives in the presence of base. Antifungal activity of synthesised naphthoquinones was evaluated against ATCC and PYCC reference strains of Candida. The results suggest that the naphtho[2,3-d]isoxazole-4,9-dio...

Quinazolinone and quinazolinedione derivatives are of considerable interest due to their wide array of pharmacological properties. In this paper we report the synthesis of ten quinazolinediones. The previous isolation of two of these compounds, namely 1-methyl-3-(2'-phenylethyl)-1H,3H-quinazoline-2,4-dione and 1-methyl-3-[2'-(4'- methoxyphenyl)ethyl]-lH,3H-quinazoline-2,4-dione, from the seed h...

In the structure of the title compound, [Ag(C(2)H(3)O(2))(C(12)H(6)N(2)O(2))]·3H(2)O, the Ag(I) atom is coordinated by both 1,10-phenanthroline-5,6-dione N atoms and one O atom from the acetate anion. The three water mol-ecules are involved in extensive hydrogen bonding to each other and to the acetate O and 1,10-phenanthroline-5,6-dione O atoms. In addition, there are weak C-H⋯O inter-actions.

A novel molecular scaffold, dihydropyridothienopyrimidin-4,9-dione, was synthesized from benzylamine or p-methoxybenzylamine in six steps involving successive ring closure to form a fused ring system composed of dihydropyridone, thiophene and pyrimidone. The pharmacological versatility of the dihydropyridothenopyrimidin-4,9-dione scaffold was demonstrated by inhibitory activity against metabotr...

Studies on the presence of free estrogens and progestogens in human prostates clearly differentiate the benign hypertrophied prostates from normals. Both contained 17 alpha-hydroxypregnenolone 5 beta-pregnane-3, 20-dione, 5 alpha-pregnane-3, 20-dione and 16 alpha-hydroxyestrone. However, presence of 11 alpha-hydroxyprogesterone 20 beta-hydroxypregnenolone, pregnenolone, 17 alpha-hydroxyprogeste...

Microorganisms were screened for ones that reduced 3,5,5-trimethyl-2-cyclohexene-1,4-dione (ketoisophorone; KIP), and several strains were found to produce (6R)-2,2,6-trimethylcyclohexane-1,4-dione (levodione). The enzyme catalyzing the reduction of the C=C bond of KIP to yield (6R)-levodione was isolated from Candida macedoniensis AKU4588. The results of primary structural analysis and its enz...

In 1-cyclohexyl-6,6,8a-trimethyl-3a,6,7,8a-tetrahydro-1H-1-benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione, C19H27NO3, (I), and the isomorphous compounds 6,6,8a-trimethyl-1-phenyl-3a,6,7,8a-tetrahydro-1H-1-benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione, C19H21NO3, (II), and 6,6,8a-trimethyl-1-(3-pyridyl)-3a,6,7,8a-tetrahydro-1H-1-benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione, C18H20N2O3, (III), the tetrahydroben...

In a previous work (Callegari and Yokoyama 2007, Celestial Mechanics and Dynamical Astronomy vol. 98), the main features of the motion of the pair Enceladus-Dione were analyzed in the frozen regime, i.e., without considering the tidal evolution. Here, the results of lots of numerical simulations of a pair of satellites similar to Enceladus and Dione crossing the 2:1 mean-motion resonance are sh...

Two new polyketides: 2Z-(heptadec-12-enyl)-4-hydroxy-3,4,7,8-tetrahydro-2H-chromen-5(6H)-one (1) and 2-(heptadec-12-enyl)-5-hydroxy-5,6,7,8-tetrahydrochromen- 4-one (2), together with eleven known compounds: 4-hydroxy-2-[(3,4-methylenedioxy- phenyl)tridecanoyl] cyclohexane-1,3-dione (3), oleiferinone (4), 4-hydroxy-2-[(3,4- methylenedioxyphenyl)undecanoyl]cyclohexane-1,3-dione (5), 4-hydroxy-2-...