MUREIDOMYCIN-E AND MUREIDOMYCIN-F, MINOR COMPONENTS OF MUREIDOMYCINS

Mureidomycins (MRDs) E and F were isolated from a culture filtrate of Streptomyces flavidovirens SANK 60486 which produces MRDs A-D. They po ssessed the same molecular formulae, C39H48N8O12S and very similar UV, IR and NMR spectra, but differed clearly from each other in HPLC prof ile. From the hydrolysates of MRDs E and F, 8-hydroxy-1,2,3,4-tetrahyd ro-3-isoquinoline carboxylic acid and 6-hydroxy-1,2,3,4-tetrahydro-3-i soquinoline carboxylic acid were detected, respectively, which were no t-detected from those of MRDs A-D. They showed strong anti-pseudomonal activity but less active than MRD A. MRDs E and F were synthesized fr om MRD A and formaldehyde through Piclet-Spengler reaction.