6241
important to affect our qualitative conclusions concerning the role of the radical site. l 2 (12) We gratefully acknowledge the generous financial support of the National Institutes of Health (GM12755 and FR00354). (13) To whom inquiries should be addressed a t the Department of Chemistry, Cornell University, Ithaca, N. Y . 14850.
F. W. McLafferty,I3 G . E. Van Lear, R. Kornfeld Departmerir of Chemistry, Purdue Uniuersity Lafayette, Indiana 47907 Receitied May 25, 1968
Chemistry of the Streptovaricins. of Varicinal A’
IV. Structure
Sir: We recently reported2 that streptovaricin A (CW Hj3NOI6),a crystalline component of the antituberculosis streptovaricin antibiotic complex, on periodate oxidation gives prestreptovarone (CZ9H2,NO,),containing the chromophore of the antibiotic. We have now isolated the other, nonchromophoric product of this oxidation and assign structure I to the compound, which we have named varicinal A.
Although the electron impact produced mass spectrum of varicinal A ( C I ~ H ~ O O ~ . Found: C, Anal. 53.95; H, 7.17) does not contain a molecular ion, characteristic ions are found at mje 271 (M - OH), 270 (M - H20), 257 (M - CH,O), and 228 (M - HOAc), T, multiplicity J , Hz
J,
I
I
a
7
9.03,d
(a801
7
195,s
8.80,d (9.03)
A -
‘
I
L H A OCOCH,
I
7
284.q
H-C-CH-0
-CH-CH-CH-
7 ,multiplicity
Bernstein, “High-Resolution Nuclear Magnetic Resonance,” McGrawHill Book Co., Inc., New York, N. Y., 1959, p 397. (6) K. L. Rinehart, Jr., W. S. Chilton, M. Hichens, and W. von Phillipsborn, J . Am. Chem. Soc., 84, 3216 (1962); I. J. McGilveray and I
