The title macrocycle, C26H30N2O6,(VI), was obtained bydirect amide cyclization'from the linear precursor 3-hydroxy-N-[1-methyl-1-(N-methyl-N-phenylcarbamoyl) ethyl]-2- phenylpropanamide, the N-methylanilide of rac-2-methyl-2-[(3-hydroxy-2-phenylpropanoyl) amino] propanoic acid, C13H17NO4,(IV). The reaction proceeds via the intermediate rac-2- (2-hydroxy-1-phenylethyl)-4, 4-dimethyl-1, 3-oxazol-5 (4H)-one, C13H15NO3,(V), which ...