Relative configuration of micrograms of natural compounds using proton residual chemical shift anisotropy

Residual chemical shift anisotropy (RCSA): a tool for the analysis of the configuration of small molecules.

Relative configuration of natural products using NMR chemical shifts.

We have measured and quantum chemically computed NMR chemical shifts for three monoterpene diastereomers produced by the walkingstick, Anisomorpha buprestoides. By taking into account the Boltzmann distribution of conformers, the combined RMSDs between experimental and calculated (1)H and (13)C NMR shifts were able to determine the correct isomer, especially when only aliphatic nuclei were used...

Chemical shift anisotropy amplification.

A new NMR experiment which allows a measurement of the chemical shift anisotropy (CSA) tensor under magic angle spinning (MAS) is described. This correlates a fast MAS spectrum in the omega2 dimension with a sideband pattern in omega1 in which the intensities mimic those for a sample spinning at a fraction of the rate omega r/N, and these sidebands result from an amplification by a factor N of ...

detection of volatile compounds of medicinal plants with some nano-sorbents using modified or new methodologies and investigation of antioxidant activity of their methanolic extracts

in this work, a novel and fast method for direct analysis of volatile compounds (davc) of medicinal plants has been developed by holding a filament from different parts of a plant in the gc injection port. the extraction and analysis of volatile components of a small amount of plant were carried out in one-step without any sample preparation. after optimization of temperature, extraction time a...

chemical recycling of polycarbonate waste using conventional heating and microwave assisted method

پلی کربنات یکی از پلاستیکهای مهمی است که به صورت گسترده در تولید لوحهای فشرده، قطعات رایانه، مواد ساختمانی و غیره مورد استفاده قرار می گیرد. این پلیمر بصورت عمده از تراکم مونومر بیس فنولa (bpa) و کربنیل کلرید یا دی متیل کربنات ها بدست می آید. در سالهای اخیر بازیافت شیمیایی پلی کربنات بیشتر مورد توجه بوده است. بازیافت شیمیایی پلی کربنات برای بدست آوردن مواد اولیه آن با روشهای متفاوتی مانند تجزی...