Organic compounds

Antibiotic S7481/F-1 having the following characteristics, when an amorphous form:

• U.v. spectrum [CH.sub.3 OH;
• c = 1.063 g/1;
• d = 0.01 cm] as shown in FIG. 1 of the accompanying drawings,
• I.r. spectrum [CH.sub.2 Cl.sub.2 ] as shown in FIG. 2 of the accompanying drawings,
• Proton N.M.R. spectrum [90 MHz;
• CDCL.sub.3 ] as shown in FIG. 3 of the accompanying drawings,
• High resolution mass spectrum [ion acceleration 4kv;
• temperature ion source 290.degree. C;
• pressure 5.10.sup.-6 mm Hg] peak of mass = m/e 1183.831 [.+-. 0.004] corresponding to C.sub.62 H.sub.109 N.sub.11 O.sub.11 recognisable as product of elimination of water from C.sub.62 H.sub.111 N.sub.11 O.sub.12 ;
• and empirical formula C.sub.62 H.sub.111 N.sub.11 O.sub.12 ;
• or antibiotic S7481/F-2 having the following characteristics, when in amorphous form:
• U.v. spectrum [CH.sub.3 OH;
• c = 1.062 g/l;
• d = 0.01 cm] as shown in FIG. 4 of the accompanying drawings;
• I.r. spectrum [CH.sub.2 Cl.sub.2 ] as hown in FIG. 5 of the accompanying drawings;
• Proton N.M.R. spectrum [90 MHz;
• CDCl.sub.3 ] as shown in FIG. 6 of the accompanying drawings;
• High resolution mass spectrum [ion acceleration 4 kv;
• ion source temperature 290.degree. C;
• pressure 5.10.sup.-6 mm Hg] peak of mass m/e 1169.815 (.+-. 0.006) corresponding to C.sub.61 H.sub.107 N.sub.11 O.sub.11, the product of water elimination from C.sub.61 H.sub.109 N.sub.11 O.sub.12 ;
• empirical formula C.sub.61 H.sub.109 N.sub.11 O.sub.12.