IBDA/LiBr-mediated functionalisation of ent-trachyloban-19-oic acid
… ent-Trachyloban-19-oic acid (1) was isolated from sunflower Helianthus annuus L. [1-4].
It exhibited weak cytotoxic activity against gastric carcinoma [5] and displayed in vivo antiinflammatory
activity [4]. In order to obtain new polyfunctionalized tetracyclic terpenoids, the
transformation of ent-trachyloban-19-oic acid (1) was carried out by studying a PhI(OAc)2/LiBr
reaction [6]. As a result, a mixture of polyfunctionalized tetracyclic diterpenoids (2) and (3)
was obtained, which was purified by column chromatography. The major compound (2) (61%) …
It exhibited weak cytotoxic activity against gastric carcinoma [5] and displayed in vivo antiinflammatory
activity [4]. In order to obtain new polyfunctionalized tetracyclic terpenoids, the
transformation of ent-trachyloban-19-oic acid (1) was carried out by studying a PhI(OAc)2/LiBr
reaction [6]. As a result, a mixture of polyfunctionalized tetracyclic diterpenoids (2) and (3)
was obtained, which was purified by column chromatography. The major compound (2) (61%) …