New Chemical Constituents from the Endophyte Streptomyces Species LR4612 Cultivated on Maytenus hookeri

From solid cultures of the biologically important endophyte Streptomyces species LR4612, cultivated on Maytenus hookeri, four new and two known compounds were isolated. The new compounds were identified as (2S*,3S*)-5-amino-3-hydroxy-5-oxopentan-2-yl 3-(formylamino)-2-hydroxybenzoate (1), N-[(3R*,4R*)-3-amino-3,4-dihydro-4-methyl-2,6-dioxo-2H,6H-1,5-benzodioxocin-10-yl]formamide (2), (5beta,6alpha)-6,11-dihydroxyeudesmane (3), and 5-(6,7-dihydroxy-6-methyloctyl)furan-2(5H)-one (4); the known compounds were elucidated as sorbicillin (5) and N-acetyltyramine (6). The structures were established by HR-ESI-MS and in-depth NMR analyses.