270‐MHz Nuclear‐Magnetic‐Resonance Study on Linear Gramicidin A in Dimethylsulfoxide

Abstract
Based on the finding of 2 sets of coupling constants (8.8 Hz and 6.7 Hz) in the 270-MHz PMR spectra of linear gramicidin in dimethylsulfoxide and the comparison of its IR spectrum with those of known conformations of alternating poly(.gamma.-benzyl-D-glutamate-.gamma.-benzyl-L-glutamate), it is proposed that the antibiotic has an LD-ribbon structure.