Synthesis and biological evaluation of ( − )-13,14-dihydroxy-8,11,13-podocarpatrien-7-one and derivatives from (+)-manool

<div><p>13,14-Dihydroxy-8,11,13-podocarpatrien-7-one (<b>1</b>) and a series of ring C aromatic diterpene derivatives were synthesised from (+)-manool (<b>4</b>) and evaluated for their cytotoxic, leishmanicidal and trypanocidal activities. Our results indicated that compound <b>1</b> and other podocarpane-type intermediates are cytotoxic. Cleavage of C6–C7 bond of compound <b>7</b> improved cytotoxic activity, indicating that, in particular, the 6,7-<i>seco</i>-podocarpane-type compound <b>20</b> might serve as a lead compound for further development.</p></div