L-leucine diacid by use of tosyl chloride in the presence of N,N-dimethylformamide" onerror="this.onerror=null;window.coverFallback&&coverFallback(this);">
Direct polycondensations of N,N′-(4,4′-oxydiphthaloyl)-bis-L-leucine diacid by use of tosyl chloride in the presence of N,N-dimethylformamide