Structure 1 was reported for a novel antifungal agent, L-657,398, isolated from fermentations of Aspergillus ochraceusP However, the relative and absolute stereochemistry of this compound were not reported. We have isolated a compound with the same structure (exclusive of stereochemistry) from fermentations of Preussia sp., by extraction of the mycelial cake with methanol and purification of th...

A simple highly versatile and efficient sonochemical synthesis of 1,2,4,5-tetrasubstituted and 2,4,5-trisubstituted imidazoles is achieved by condensation of 1,2-dicarbonyl compound, aldehyde, ammonium acetate and primary amine using antimony trichloride immobilized on silica gel (SiO2-OSbCl2) as a catalyst in ethanol at moderate temperature. Operational simplicity, practicability and applicabi...

Repeated silica gel and octadecyl silica gel (ODS) column chromatography of the aerial parts of Artemisia princeps PAMPANINI (Sajabalssuk) led to the isolation of a new sesquiterpenoid, 3-((S)-2-methylbutyryloxy)-costu-1(10),4(5)-dien-12,6 alpha-olide (2), along with two previously reported sesquiterpenoids: 8 alpha-angeloyloxy-3beta,4 beta-epoxy-6 beta H,7 alpha H,8 beta H-guaia-1(10),11(13)-d...

The high temperature form of melanophlogite, 46 Si02. 6M14 .2M12(M12=CH4, N2; M14=C02, N2), is cubic with space group Pm3n and a = 13.436(3) A at 200°C. The mineral is isostructural with the cubic gas hydrates of type I. Structure refinement with 667 independent reflections led to a weighted Rw = 0.040. Corner-sharing [Si04] tetrahedra form a 3dimensional framework which contains two types of c...

The edible blue-green alga (cyanobacterium), Suizenji-nori, contained 143.8+/-22.4 microg of vitamin B(12) per 100 g dry weight of the alga (mean+/-SE, n=4). A corrinoid compound was purified from the dried Suizenji-nori, and partially characterized. The silica gel 60 TLC and reversed-phase HPLC patterns of the purified corrinoid compound were not identical to those of true vitamin B(12), but t...

The hydroxyl radical scavenging capacity and efficacy of a novel organosiliceous anionic hydride compound, silica hydride, were quantified by a recently developed method. The method measures a direct relationship between the hydroxyl radical scavenging capability of the antioxidant compound and the linear decrease in signal from a fluorescent 2-hydroxyterephthalate product created by reacting a...

A phytochemical study on the flowe r of Calotropis gigantea (Linn.) using silica gel column chromatography and preparative thin layer chromatography, led to the first time isolation of Di-(2-ethylhexyl) phthalate (compound 1) and anhydrosophoradiol-3-acetate (compound 2). The structures of these compounds were confirmed by spectroscopic analyses (IR, HRTOFMS and NMR). The antibacterial and anti...

The present study synthesizes a novel adsorbent by coating Fe3O4 magnetic nanoparticles with amino functionalized mesoporous silica. The FTIR spectrums indicate that silica has been successfully coated on the surface of Fe3O4 and 3-aminopropyl tri methoxysilane compound have been grafted to the surface of silica-coated Fe3O4. The XRD analysis shows the presence of magnetite phase with cubic spi...

Clitocybin D, a novel human neutrophil elastase inhibitor, was isolated from the culture broth of Clitocybe aurantiaca. This compound was purified by solvent extraction, silica gel column chromatography, Sephadex LH-20 column chromatography, and preparative HPLC. The compound was determined to be 4-(4,6-dihydroxy-3-methoxy-3H-isoindol-1-yl)-benzoic acid on the basis of 1D and 2D NMRs and MS spe...