Natural product analysis, nuclear spectroscopy

Yang Z. Online hyphenated liquid chromatography-nuclear magnetic resonance spectroscopy-mass spectrometry for drug metabolite and nature product analysis. J Pharm Biomed Anal 2006 40 516-527. 

Natural products—Analysis. 2. Nuclear magnetic resonance spectroscopy. I. Rahman. Atta-ur-, 1942- II. Ahmad, Viqar Uddin. III. Title Carbon-thirteen NMR of natural products. 

Gossi, A., Uta, S., and Gotz, S. 2012, Thin-layer chromatography-nuclear magnetic resonance spectroscopy—A versatile tool for pharmaceutical and natural products analysis, CHIMIA, 66 347-349. 

Within the past two decades, the importance of nuclear magnetic resonance (n.m.r.) spectroscopy has enlarged tremendously. Its advantages over other methods in the structural and conformational analysis of such complex molecules as natural products, and particularly with regard to the still-increasing importance of medical investigations using n.m.r. techniques, is abundantly evident. Because destruction of the sample is avoided, different n.m.r. experiments can be performed repeatedly, and... 

Analytical Methods. Identification of Terpenols in Essential Oils by Trifluoroacetylation and F N.m.r. Spectroscopy . Chemical Study of Trifluoroacetyl Signal in the F N.m.r. Spectra of Trifluoroacetylated Natural Products . Structure Determination of Trifluoroacetyl Steroids by F N.m.r. ." Determination of Structure and Quantitative Analyses of Hydroxy Steroids in the Microgram Range. Analysis of Hydroxy Steroids by F N.m.r. Spectroscopy . Nuclear Magnetic Resonance Studies of the Interaction of... 

Chemical methods As with many areas of natural product chemistry, new impetus in the chemistry of lichen substances is provided by the more rapid and improved methods for detecting, isolating and purifying these compounds and in determining their structure. The techniques of preparative TLC, radial chromatography and preparative HPLC provide rapid and efficient methods for the purification of lichen substances and developments in mass spectrometry, proton and carbon-13 nuclear magnetic resonance (NMR) spectroscopy and X-ray analysis greatly aid structural smdies. 

Difference FT-IR spectroscopy has given natural products chemists and bio-organic chemists another new tool in structure analysis that is extremely sensitive. Selective examination of specific bond vibrations through difference spectroscopy provides structural information that is not dependent upon an abundant nucleus possessing nuclear spin. Difference FT-IR spectroscopy offers the opportunity to... 

The distilled products were homogenous by gas liquid chromatographic analysis (GLC). They were completely characterised by elemental analysis, as well as infra-red (IR), MS and H- and C-nuclear magnetic r-esonance (MR) spectroscopy all the results being in accord with the structures 2-4. The C-NMR data are collected in Table 2. The H-NMR data for 2, and the MS of 2-4 agreed with the values reported for the natural products. ... 

Nuclear magnetic resonance (NMR) spectroscopy has grown into an indispensable tool for structure determination of new compounds and chemical analysis of natural products. This technique has found a wide range of applications from the characterization of synthetic products to the study of molecular structures of biological systems. 

Progress in photochemistry could only be made following progress in spectroscopy and, in particular, the interpretation of spectra in at least semiquantitative terms, but history has shown that this was not enough. The arrival of new methods of analysis which permit determination of small amounts of products, the development of flash photolysis, nuclear magnetic resonance, and electron spin resonances which can yield valuable information about the natures of intermediate excited states, as well as of atoms and radicals, all have permitted the photochemist to approach the truly fundamental problem of photochemistry What is the detailed history of a molecule which absorbs radiation ... 

---