Biosynthesis of natural products. Part 3. Syntheses of ent-[17-14C]kaur-16-en-20-ol from enmein and of ent-[17-14C]kaur-16-ene derivatives oxygenated at C-3 from ent-kaur-16-ene-3β,19-diol

Abstract

ent-[17-¹⁴C]Kaur-16-en-20-ol (5b) was synthesised from enmein (3), and ent-[17-¹⁴C]kaur-16-en-3β-ol (6b), ent-[17-¹⁴C]kaur-16-en-3-one (7b), and ent-[17-¹⁴C]kaur-16-en-3α-ol (8b) were synthesised from ent-kaur-16-ene-3β,19-diol (9). These labelled compounds were required for the investigation on the biosynthetic route from ent-kaur-16-ene (1) into enmein (3) and oridonin (4).