THE CHEMISTRY OF LEUCOMYCINS. VI

STRUCTURES OF LEUCOMYCIN A₄, A₅, A₆, A₇, A₈ AND A₉

Abstract

Studies on the structures of new components of leucomycin, A₄(IV), A₅(III), A₆(VI), A₇(V), A₈(VIII) and A₉(VII), were carried out in parallel with those on components A₁(I) and A₃(II), namely acetylation, and acid and alkaline hydrolysis. The pairs of components IV and III, VIandV, and VIIand VIII gave respectively, acetates X, XI and XIII. Components IV, VI and VIII had then respectively, 4-O-n-butyryl-, 4-O-propionyl- and 4-O-acetyl-mycarose replacing the 4-O-isovaleryl mycarose in the A₃. Like A₃, components IV, VI and VII had an O-acetyl group on C-3 of the 16-membered lactone.