BENZODIAZEPINE ANALOGS - PART 18 - C-13 NMR ANALYSIS OF SCHMIDT REARRANGEMENT PRODUCTS FROM FLAVONONE ANALOGS

C-13 NMR spectra of 1,4- and 1,5-benzoheterazepinones and their tetraz olo derivatives, prepared by the Schmidt rearrangement of flavanone an alogues, are reported. The effects of the C-ring heteroatoms on the C- 13 NMR chemical shifts of the ring-expanded products were found to be of diagnostic value in distinguishing the isomeric products from one a nother and from the corresponding precursors. (C) 1998 John Wiley & So ns, Ltd.