Chapter 8: Nuclear Magnetic Resonance of Steroids

In the following chapter, the nuclear magnetic resonance (NMR) spectroscopic investigation of steroids is described. After a short introduction, the historic cross-fertilization between steroids and NMR is briefly described. The application of modern and “rare” methodologies is presented for the structure elucidation of steroids. Studies using high-resolution and high-sensitivity experiments, such as homodecoupled or pure shift 1D ¹H experiments, are collected, as well as investigations based on pure heteronuclear techniques, such as ¹³C–¹³C INADEQUATE, or correlation techniques, such as H–F HOESY and HMQC. The utilization of residual dipolar couplings in addition to the nuclear Overhauser effect and J-resolved spectroscopy is discussed with respect to their application in steroid stereochemistry elucidation. Covariance transformation methods are discussed in the context of their application to steroids, and the effects of spectral crowding specifically are investigated. Finally, strategies for the elucidation and verification of steroid structures are elaborated. To illustrate their application, examples of suitable techniques such as H–C HSQC-TOCSY, H–C H2BC, and 1,1-ADEQUATE are provided.