Albusamides\nA–G: Hydroxylated Fatty Amine Derivatives\nfrom the Deep-Sea-Derived Actinomycete <i>Streptomyces albus</i> 228DD-066 and Their Cytotoxic Activity

A series\nof new hydroxylated fatty amine derivatives, albusamides\nA–G (<b>1</b>–<b>7</b>), along with four\nknown compounds (<b>8</b>–<b>11</b>), which are\nreported for the first time from a natural source, were isolated from\nthe culture broth of <i>Streptomyces albus</i> 228DD-066\nderived from a deep-sea sediment sample gathered off the coast of\nDokdo Island, Republic of Korea. Their structures were elucidated\nthrough the comprehensive analysis of 1D and 2D NMR spectra and HRESIMS,\nand absolute configurations were determined using the modified Mosher’s\nmethod. Biological evaluations against solid and blood cancer cell\nlines revealed that these new metabolites have moderate to strong\ncytotoxic activity. Compound <b>3</b> exhibited high cytotoxic\nactivity with GI<sub>50</sub> values ranging from 0.4 to 0.6 μM\nagainst solid cancer cell lines and exhibited the strongest cytotoxicity\n(GI<sub>50</sub> value = 0.2 μM) against the WSU-DLCL2 blood\ncancer cell line.