New Polyisoprenylated Polycyclic Phloroglucines from Clusia gundlachii

Abstract

A bioassay-guided fractionation yielded five new polycyclic phloroglucines derivatives, namely, gundlachiione A (1), gundlachiione B (2), gundlachiione C (3), gundlachiione D (4) and gundlachiione E (5) from the fruits of Clusia gundlachii, collected in Puerto Rico, USA. Their structures were determined by full spectroscopic data, including 2D NMR COSY, HMQC, HMBC, and NOESY experiments, and HRESIMS. Compounds 1 and 3 demonstrated activities against Leishmania donovani intracellular macrophage amastigotes in THP1 cultures, comparable to those observed for the standard drug pentamidine (IC 50 and IC 90 values 0.84 and 6.13 μg/mL, 2.32 and 3.01 μg/mL, 0.77 and 2.99 μg/mL, respectively). Both compounds, 1 and 3, also showed weak activities against L. donovani promastogotes and absence of cytotoxicity against transformed THP 1 cells.