Melotenine A, isolated from Melodinus tenuicaudatus, possesses significant anticancer activity against several human cancer cell lines. The synthesis of (±)-melotenine A was achieved without the use of any protecting groups in 11 steps with an overall yield of 6.7%. The key steps of our strategy were a Diels–Alder reaction to construct the tetracyclic framework and ring-closing metathesis to form the seven-membered ring of (±)-melotenine A.

Carbohydrates have played an important role in organic synthesis. Since they contain many stereocenters, they have been widely used as chiral-pool starting materials. Herein, we report the asymmetric formal synthesis of (–)-swainsonine, which exhibits anticancer and immunosuppressive activities and inhibits lysosomal α-mannosidase activity, from d-mannose and d-arabinose. The synthesis utilized Zn-mediated Bernet–Vasella reaction, Horner–Wadsworth–Emmons olefination, and Grubbs olefin metathesis as key reactions.

Reported herein is the total synthesis of anticancer pacharin, bauhiniastatin 4, and bauhinoxepins C and D. The synthetic strategy features a cascade reaction involving intermolecular nucleophilic aromatic substitution followed by intramolecular Knoevenagel condensation to form a dibenzo[b,f]oxepine scaffold of these compounds. Pacharin and bauhiniastatin 4 were synthesized in eight steps from 2-methylresorcinol with overall yields of 5.4% and 8.3%, respectively. Similarly, bauhinoxepins C and D were synthesized in seven steps with overall yields of 3.5% and 2.6%, respectively. This methodology offers an efficient route for accessing these natural products with implications for medicinal and synthetic chemistry.