Sclerin, a New Cytotoxic Cyclononapeptide from <i>Annona scleroderma</i>
Francisco Cen-Pacheco,
Gerardo Valerio-Alfaro,
Dalia Santos-Luna,
José Javier Fernández
Affiliations
Francisco Cen-Pacheco
Faculty of Bioanalysis, Veracruz University, Iturbide s/n, Veracruz 91700, Mexico
Gerardo Valerio-Alfaro
Food Research and Development Unit, Tecnológico Nacional de México-I T Veracruz-UNIDA. M.A. de Quevedo 2779, Col. Formando Hogar Veracruz Ver. C.P., Mexico 91860, Mexico
Dalia Santos-Luna
Faculty of Bioanalysis, Veracruz University, Iturbide s/n, Veracruz 91700, Mexico
José Javier Fernández
Institute of Bio-Organic Chemistry Antonio González, Department of Organic Chemistry, University of La Laguna, Astrofísico Francisco Sánchez 2, 38206 La Laguna, Tenerife, Spain
A new cytotoxic cyclononapeptide, sclerin, cyclo(⁻Dab1⁻Ser2⁻Tyr3⁻Gly4⁻Thr5⁻Val6⁻Ala7⁻ Ile8⁻Pro9⁻) (1), was isolated from the methanol extract of the seeds of Annona scleroderma, together with the known metabolite, cyclosenegalin A, cyclo(⁻Pro1⁻Gly2⁻Leu3⁻Ser4⁻Ala5⁻Val6⁻Thr7⁻) (2). The planar structures for the two compounds were established by comprehensive analysis of NMR and ESI-HRMS data, and the absolute stereochemistry was stablished by Marfey’s method. Compound 1 showed moderate cytotoxic activity against the human prostate carcinoma cell line DU-145 at µM concentration.
