3β-Senecioyloxy-6β-ethoxy-10βH-furanoeremophilane

Taxonomy: Physicochemical and Pharmacological Properties of Sesquiterpene Esters – The Bicyclic Sesquiterpene Esters – Eremophilanes – Furanoeremophilanes – Monoesters

Biological sources: Petasites niveus Baumg. [1]

C₂₂H₃₂O₄: 360.2301

Mp: colorless oil [1]

[α] ²²_D −25.2° (CHCl₃, c 0.40) [1]

UV (cyclohexane) 219 (3.96) [1]

IR (film): 1704, 1653, 1560 [1]

MS: 360 [M]⁺ (0.5), 260 (0.5), 152 (100), 123 (60), 108 (23), 83 (17), 55 (5) [1]

HPLC: [1]

¹ H NMR (CDCl₃, C₆D₆): 0.95, 0.99 (3H, d, J = 7.1, H-15), 0.97, 1.03 (3H, s, H-14), 1.25, 1.24 (3H, t, J = 7.0, −CH₂Me), 1.89, 1.45 (3H, d, J = 1.2, Me trans to −C(O)O−),2.03, 2.01 (3H, d, J = 1.2, H-13), 2.17, 2.13 (3H, d, J = 1.2, Me cis to −C(O)O−), 2.19, 2.05 (1H, m, H-9α), 2.78, 2.65 (1H, m, which, on irradiation at H-12, became a ddd, J = 17.0; 6.1; 2.2, H-9β), 4.60, 4.65 (1H, m, H-6), 5.33, 5.46 (1H, m, H-3), 5.70, 5.81 (1H, m, =CHC(O)O−), 7.03, 7.04 (1H, m, H-12), (OCH₂ in CDCl₃appeared as two quartets centred at 3.89 and 3.88, J = 7.0,...