Abstract: Sponges biosynthesize α-methoxylated fatty acids with unusual biophysical and biological properties and in some cases they display enhanced anticancer activities. However, the antiprotozoal properties of the α-methoxylated fatty acids have been less studied. In this work, we describe the total synthesis of (5Z,9Z)-(±)-2-methoxy-5, 9-eicosadienoic acid (1) and its acetylenic analog (±)-2-methoxy-5,9-eicosadiynoic acid (2), and report that they inhibit (EC50 values between 31 and 22 µM) the Leishmania donovani DNA topoisomerase IB enzyme (LdTopIB). The inhibition of LdTopIB (EC50 = 53 µM) by the acid (±)-2-methoxy-6-icosynoic acid (12) was studied as well. The potency of LdTopIB inhibition followed the trend 2 > 1 > 12, indicating that the effectiveness of inhibition depends on the degree of unsaturation. All of the studied α-methoxylated fatty acids failed to inhibit the human topoisomerase IB enzyme (hTopIB) at 100 µM. However, the α-methoxylated fatty acids were capable of inhibiting an active but truncated LdTopIB with which camptothecin (CPT) cannot interact suggesting that the methoxylated fatty acids inhibit LdTopIB with a mechanism different from that of CPT. The diunsaturated fatty acids displayed low cytotoxicity towards Leishmania infantum promastigotes (EC50 values between 260 and 240 µM), but 12 displayed a better cytotoxicity towards Leishmania donovani promastigotes (EC50 = 100 µM) and a better therapeutic index.
This is an open access article distributed under the
Creative Commons Attribution License which permits unrestricted use, distribution,
and reproduction in any medium, provided the original work is properly cited.
Export to BibTeX
MDPI and ACS Style
Carballeira, N.M.; Montano, N.; Alvarez-Velilla, R.; Prada, C.F.; Reguera, R.M.; Balaña-Fouce, R. Synthesis of Marine α-Methoxylated Fatty Acid Analogs that Effectively Inhibit the Topoisomerase IB from Leishmania donovani with a Mechanism Different from that of Camptothecin. Mar. Drugs 2013, 11, 3661-3675.
Carballeira NM, Montano N, Alvarez-Velilla R, Prada CF, Reguera RM, Balaña-Fouce R. Synthesis of Marine α-Methoxylated Fatty Acid Analogs that Effectively Inhibit the Topoisomerase IB from Leishmania donovani with a Mechanism Different from that of Camptothecin. Marine Drugs. 2013; 11(10):3661-3675.
Carballeira, Néstor M.; Montano, Nashbly; Alvarez-Velilla, Raquel; Prada, Christopher F.; Reguera, Rosa M.; Balaña-Fouce, Rafael. 2013. "Synthesis of Marine α-Methoxylated Fatty Acid Analogs that Effectively Inhibit the Topoisomerase IB from Leishmania donovani with a Mechanism Different from that of Camptothecin." Mar. Drugs 11, no. 10: 3661-3675.