STUDIES ON THE CARDIAC GLYCOSIDES OF THEVETIA PERUVIANA MERR.SYN.THEVETIA NERIIFOLIA JUSS.——Ⅱ.ISOLATION AND IDENTIFICATION OF CERBERIN,RUVOSIDE,AND A NEW CARDIAC GLYCOSIDE——PERUSITIN

In addition to the four cardiac glycosides reported in the previous paper, three more cardiac glycosides A, D, E, were isolated from the seeds of Thevetia peruviana Merr. Glycoside A, C₃₂H₄₈O₉, m.p.215—218%,α_D²⁹—82.4 (c=1.1412, methanol). U.V. λ_max 218mμ (log ε, 4.19), IR (KBr) 2.96, 5.57, 5.67—5.78, 6.20, 7.25, 7.82—8.0, 9.80μ, on mild hydrolysis yielded a crystalline deacetyl derivative—Neriifolin, while on acetylation gave diacetylneriifolin. Thus glycoside A was proved to be cerberin (Monoacetylneriifolin) by the above evidence. Glycoside D, C₃₀H_(46)O₉,m.p.239—240%,α_D²⁹—55.5 (c=1.2727, methanol), U.V. λ_max 218 mμ (logε, 4.21), IR (KBr) 2.97, 5.79, 6.20, 7.25, 9.80 μ, was identified as ruvoside. It was also further characterized by comparing with the reduction product of peruvoside. Glycoside E, under the name of perusitin, C₃₀H₄₄O₁₀, m.p. 168—170%, α_d^28.5—45.47 (c= 1.37, methanol), pK_α 6.2, U.V. λ_max 218 mμ (log ε, 4.23), IR (KBr) 2.98, 5.59, 5.72, 5.90, 6.16, 7.26, 9.75μ, was a new acidic cardiac glycoside, IR (KBr) of its triethylamine salt showed at 6.45 μ, while the original peak at 5.90μ (—COOH) of perusitin disappeared. By oxidation of peruvoside with KMnO₄ in acetone, a crystalline product was obtained, on the basis of its melting point, mixed melting point, α_d, and IR, it was identified to be perusitin. Thus structure of perusitin was proved to be cannogeninic acid-l-thevetoside.