Two nonvolatile beta-carboline alkaloids were isolated from the Maillard reaction between xylose and tryptophan by solvent extraction and flash silica gel column chromatography. Their structures were elucidated by spectral methods (UV, MS, and NMR) as 1-(1,4-dihydroxybutyl)-beta-carboline and 1-(1,3, 4-trihydroxybutyl)-beta-carboline.

Here, we demonstrate a versatile screening platform for NHC ligand based catalysts by coating fused-silica micro capillaries with a bonded 1,3-bismesityl-2-imidazolidinylidene ligand. Such micro capillaries can be efficiently converted into (pre)-catalysts from various organometallic precursors by solid-phase chemistry techniques and can be quantitatively screened using on-column reaction chrom...

a water soluble polysaccharide, hb-1, with a molecular weight of 23,930, was isolated from radix ranunculi ternati. by hot water extraction, ethanol precipitation, deproteination，ultrafiltration and gel-filtration column chromatography. its sugar composition was determined by glc as glc, ara, and gal in a molar ration of 16.071: 2.722: 1. and the absolute configuration of glc was identified as ...

Horse heart cytochrome c linked to Sepharose 4B is used to purify reaction centers from Rhodopseudomonas sphaeroides R-26. This procedure allows for an initial recovery of 80-90% of the bacterial reaction centers present in chromatophore membranes. High purity reaction centers (A(280)/A(802) < 1.30) can be obtained with a 30% recovery. Reaction centers from wild-type Rps. sphaeroides and Rps. c...

An extremely facile and efficient procedure which has been developed for the synthesis of dihydropyrrol-2-ones. One-pot four-component reaction of amines, dialkyl acetylenedicarboxylates and formaldehyde in the presence of N,N,N,N-tetramethylguanidinium acetate [TMG][Ac] in methanol at ambient temperature provides substituted dihydropyrrol-2-ones in good to high yields. The important aspects of...

Extremely facile and efficient procedure has been developed for the synthesis of alkyl 2,5-dihydro-2-oxo-5-aryl-3-(arylamino) furan-4-carboxylate in the presence of trityl chloride (TrCl) as an organic catalyst in ethanol at ambient temperature. One-pot three-component reaction of aromatic amines, dimethyl and/or diethyl acetylenedicarboxylates and aryl aldehydes offorded the corossponding 3-am...

Water-soluble melanin complexes were extracted with hot water from Inonotus obliquus fungus. They were characterized before and after reaction with diluted hydrochloric acid. The organic components as products of degradation of melanin complexes were separated by column chromatography and analyzed by GC-MS method.

Nicole Riddell (2017): Packed Column Supercritical Fluid Chromatography: Applications in Environmental Chemistry. Örebro Studies in Chemistry 19. Although gas and liquid chromatography have emerged as dominant separation techniques in environmental analytical chemistry, these methods do not allow for the concurrent analysis of chemically diverse groups of persistent organic pollutants (POPs). T...

Post-column photochemical reaction systems have developed into a common approach for enhancing conventional methods of detection in HPLC. Photochemical reactions as a means of 'derivatization' have a significant number of advantages over chemical reaction-based methods, and a significant effort has been demonstrated to develop an efficient photochemical reactor. When coupled to electrochemical ...