The development of high-resolution NMR

1940s First observation of nuclear magnetic resonance in solids and liquids (1945) 

1950s Development of chemical shifts and spin-spin coupling constants as structural tools 

The nuclear Overhauser effect employed in structural investigations 

1970s Use of superconducting magnets and their combination with the FT approach 

1980s Development of multipulse and two-dimensional NMR techniques Automated spectroscopy 

It is now over 16 years since the first observations of NMR were made in both solid and liquid samples, from which the subject has evolved to become the principal stmctural technique of the research chemist, alongside mass spectrometry. During this time, there have been a number of key advances in high-resolution NMR that have guided the development of the subject [3-5] (Table 1.1) and consequently the work of organic chemists and their approaches to structure elucidation. The seminal step occurred during the early 1950s when it was realised that the resonant frequency of a nucleus is influenced by its chemical environment and that one nucleus could further influence the resonance of 

Routine application of pulsed field gradients for signal selection Development of coupled analytical methods, e.g. LC-NMR 

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Structure determination of the diterpenoid alkaloids (C20) has been a challenging task because of the diverse skeleta of these alkaloids. During the period ( 1962-1972), many of the structures were determined by X-ray crystal structure determination. The development of high resolution NMR and Mass spectral instruments has facilitated the structure elucidation and determination of the stereochemistry of the diterpenoid alkaloids. The structures of more than 240 naturally occurring diterpenoid alkaloids have been determined in the past twenty five years making use of, 3C NMR studies. 

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