Fast and Efficient Method to Obtain Tagitinin F by Photocyclization of Tagitinin C

There is some evidence in the literature of the photocyclization reaction of Tagitinin C (1) to Tagitinin F (2). Compound 2 has high pharmacological potential, but it is not easy to obtain, while compound 1 is easily obtained from a widespread plant, Tithonia diversifolia. Among different reaction conditions monitored, one was found that allowed the cyclization of 1 into 2 in