Semisynthesis of Dolabellane Diterpenes: Oxygenated Analogues with Increased Activity against Zika and Chikungunya Viruses

Autor: Freddy A. Ramos, Claudio Cesar Cirne-Santos, Jackson A. L. C. Resende, Ana Maria Viana Pinto, Caroline de Souza Barros, Maria Leonisa Sanchez Nunez, Izabel Christina Nunes de Palmer Paixão, Fabián Amaya García, Valéria Laneuville Teixeira, Leonardo Castellanos
Rok vydání: 2021
Předmět:
Zdroj: Journal of Natural Products. 84:1373-1384
ISSN: 1520-6025
0163-3864
Popis: Brown algae and soft corals represent the main marine sources of dolabellane diterpenes. The antiviral activity of dolabellanes has been studied for those isolated from algae, whereas dolabellanes isolated from soft corals have been barely studied. In this work, a collection of dolabellane diterpenes consisting of five natural and 21 semisynthetic derivatives was constructed, and their antiviral activities against Zika (ZIKV) and Chikungunya (CHIKV) viruses were tested. Dolabellatrienone (1) and (1R,7R,8R,11S)-7,8-epoxy-13-keto-dolabella-3,12(18)-diene (2), isolated from Eunicea genus soft corals, were employed to obtain 21 dolabellane and dolastane diterpenes by reactions such as allylic oxidations, reductions, acid-catalyzed epoxide ring opening, and acetylations. All of the compounds were identified by a combination of one- and two-dimensional NMR, mass spectrometry, and X-ray diffraction experiments. The cytotoxicites against Vero cells and the antiviral activities against ZIKV and CHIKV was tested to calculate the half-maximal effective concentration (EC50) and selectivity indexes (SIs). In general, the addition of oxygen-containing functional groups improved the bioactivity of dolabellane and dolastane diterpenes against ZIKV and CHIKV replication. Compound 9 showed an EC50 = 0.92 ± 0.08 μM and SI = 820 against ZIKV.
Databáze: OpenAIRE