Antibiotic 308

methyl 5-((3E,5E,7E)-7-hydroxy-4-methyl-7-(1-methyl-2,4-dioxopyrrolidin-3-ylidene)hepta-3,5-dien-2-yl)-2,6,9a-trimethyl-8-oxooctahydro-3a,7-epoxyfuro[3,2-b]oxocine-3-carboxylate

antibiotic A447 C

sodium,(5R,6R)-3-[(E)-2-acetamidoethenyl]sulfanyl-6-ethyl-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate

Antibiotic 2158

methyl 4-[5-(4,5-dihydroxy-6-methyloxan-2-yl)oxy-4-hydroxy-6-methyloxan-2-yl]oxy-2-ethyl-2,5,7-trihydroxy-6,11-dioxo-3,4-dihydro-1H-tetracene-1-carboxylate

Antibiotic AB 4015B