KOHOUT, L., CHODOUNSKÁ, H., MACEK, T., STRNAD, M. Synthesis of (20S)-2ŕ,3ŕ-dihydroxy-6-oxo-7-oxa-7a-homo-5ŕ-pregnane-20-carboxylic acid as a brassinosteroid part of ligand for binding to affinity chromatography carriers. Collection of Czechoslovak Chemical Communications. 2000, 65(11), 1754-1761. ISSN 0010-0765.