Dolichocarpols A‑F, Unprecedented Macrocyclic Humulene-Type Sesquiterpenoids from Anaxagorea dolichocarpa
journal contributionposted on 03.06.2020, 00:13 by Kaio Aragão Sales, Anderson Angel Vieira Pinheiro, Diego Igor Alves Fernandes de Araújo, Lucas Silva Abreu, Rodrigo Silva de Andrade, Maria de Fátima Agra, Marianna Vieira Sobral, Rafael Carlos Ferreira, Raimundo Braz-Filho, Marcus Tullius Scotti, Josean Fechine Tavares, Marcelo Sobral da Silva
Six sesquiterpenoids with unprecedented macrocyclic humulene-type structures, namely, dolichocarpols A-E (1–5) with ether-bridged bicyclic rings between C-10 and C-2, C-10 and C-7, C-10 and C-6 (×2), and C-6 and C-3 and dolichocarpol F (6) cyclized between C-7 and C-2 and with an ether bridge between C-10 and C-3, were isolated from Anaxagorea dolichocarpa roots. The structures of the compounds were elucidated by NMR, MS, and IR data. Absolute configurations of compounds 1–3 and 6 were established on the basis of data from electronic circular dichroism, whereas relative configurations of compounds 4 and 5 were suggested by the NOESY spectrum. In addition, a putative biosynthetic pathway of the compounds is proposed. Furthermore, the cytotoxicity of 3, 4, and 6 against HCT-116 (human colorectal carcinoma) and L929 (murine fibroblast) was evaluated.