# Residual Chemical Shift Anisotropies in the Structure Determination of Small Molecules

## TL;DR

This paper reviews how residual chemical shift anisotropies help determine the structure of small molecules, especially natural products.

## Contribution

The paper introduces and reviews RCSA-based methods for structural elucidation of natural compounds.

## Key findings

- RCSA is a valuable tool for determining the relative configurations of organic molecules in solution.
- The availability of alignment media in organic solvents is important for RCSA measurements.
- RCSA applications are discussed for structural analysis of natural products.

## Abstract

The determination of the relative and absolute configuration of natural compounds is a very challenging task. Among other anisotropic NMR parameters, residual chemical shift anisotropy (RCSA) induced by anisotropic media is an invaluable tool to determine relative configurations of natural and synthetic organic molecules in solution. This review introduces various RCSA‐based methodologies for the structural elucidation of natural products. The current availability of alignment media in organic solvents for RCSA measurements is also discussed as are applications of RCSAs for structural analysis of various natural products.

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