Analysis of NMR Spectral Data of Structural Analogs of Ponasterone α and 9α,20-Dihydroxyecdysone with an Isoxazoline Ring in the Side Chain

Resonances of H and C atoms in isoxazolinyl steroids, i.e., structural analogs of ponasterone A and 9α,20-dihydroxyecdysone, were assigned by two-dimensional NMR spectroscopy. Characteristic effects of neighboring functional groups on the chemical shifts of C and H atoms in the NMR spectra were revealed. Data for the spectral characteristics of the previously described compounds were refined.