Abstract
The structures of antibiotics, lankacidin A (T-2636 A), lankacidin C (T-2636 C), lankacidinol A (T-2636 D) and lankacidinol (T-2636 F) were elucidated by chemical degradations and spectral analyses. They all have the characteristic cyclo heptadeca carbon skeltone with a β-keto-δ-lactone ring. Of them lankacidin A and C have a pyruvamide group and the others have a lactamide group in their side chain. On the point of view from chemical and biological properties, these antibiotics might be in intermediate position between the macrolide and the polyene macrolide antibiotics.
