Abstract
Bioassay-guided partition of the extract of the Red Sea sponge
and HPLC purification of the active fraction gave a psammaplysin dimer, psammaceratin A (
), along with psammaplysin A (
). The dimer comprises two units of psammaplysin A (
) connected via the terminal amines with an unprecedented (2
,3
)-2,3-bis(aminomethylene)succinamide moiety, and it represents the first dimer to be identified among the psammaplysin family. Data from 1D- and 2D-NMR and HRMS supported the chemical structures of the compounds. Psammaceratin A (
) and psammaplysin A (
) exhibited significant growth inhibition of HCT 116, HeLa, and MBA-MB-231 cells down to 3.1 μM.