Studies on the ionophorous antibiotics. Part 14. Crystal and molecular structure of the thallium salt of carriomycin

Abstract

Carriomycin (I) is a new polyether antibiotic produced by Streptomyces hygroscopicus. The crystal and molecular structure of its thallium salt has been determined from three-dimensional X-ray analysis by the heavy-atom method from diffractometer data. Crystals are monoclinic, space group P2₁, a= 15.416(4), b= 12.325(5), c= 14.442(5)Å, β= 105.42(4)°, Z= 2. The structure was refined by block-diagonal least-squares methods to R 0.60 for 3 763 reflections. The carriomycin molecule contains seven ring systems: three five-membered rings take an envelope conformation, while the remaining four six-membered rings adopt a chair conformation. The molecule wraps around the thallium ion.