Secondary metabolites from the <i>Colletotrichum gloeosporioides</i> A12, an endophytic fungus derived from <i>Aquilaria sinensis</i>

<p>Two new cyclohexene derivatives colletotricones A and B (<b>1</b> and <b>2</b>) and a new thiazole derivative colletotricole A (<b>5</b>), along with six known natural metabolites were isolated from the extract of <i>Colletotrichum gloeosporioides</i> A12, an endophytic fungus derived from <i>Aquilaria sinensis</i>. Among them, the colletotricones A and B possess a cyclohexenone skeleton, whereas the colletotricole A is a thiazole derivative. Their structures were fully assigned with the aid of extensive spectroscopic analysis and data from the literature. Moreover, cytotoxic activity <i>in vitro</i> of compounds <b>1</b> and <b>3–9</b> were evaluated against MCF-7, NCI-H460, HepG-2 and SF-268 tumour cell lines. The new compound <b>1</b> exhibited growth inhibitory activity against all the four tumour cell lines with IC₅₀ values ranging from 15.7 to 46.8 μM.</p

Two new 12-membered macrolides from the endophytic fungal strain <i>Cladosprium colocasiae</i> A801 of <i>Callistemon viminalis</i>

<p>Two new polyketide metabolites, the 12-membered macrolides 4-hydroxy-12-methyloxacyclododecane-2,5,6-trione (<b>1</b>) and 12-methyloxacyclododecane-2,5,6-trione (<b>2</b>), were isolated from the endophytic fungal strain <i>Cladosprium colocasiae</i> A801 of the plant <i>Callistemon viminalis</i>, together with five known derivatives<i>.</i> Their structures were fully characterized by means of detailed spectroscopic analysis for new structures, and in comparison with published data for known compounds. The antibacterial, cytotoxic, and α-glucosidase inhibitory activities of the new compounds <b>1</b> and <b>2</b> were evaluated.</p