New Chemical Constituents ofEuphorbiaquinquecostataand Absolute Configuration Assignment by a Convenient Mosher Ester Procedure Carried Out in NMR Tubes

Two new compounds, an ent-isopimarane-type diterpene, 3α,12α-dihydroxy-ent-8(14),15-isopimaradien-18-al (1), and a dihydrobenzo[b]furan neolignan, (−)-trans-9-acetyl-4,9‘-di-O-methyl-3‘-de-O-methyldehydrodiconiferyl alcohol (2), along with five known compounds, 7,7‘-dihydroxy-6,8‘-bicoumarin (bicoumol) (3), 3,4-dimethoxycinnamaldehyde (4), 6-hydroxy-7-methoxycoumarin (isoscopoletin), N-butylaniline, and vanillin, have been isolated from an ethyl...