ASSIGNMENT OF H-1 AND C-13 NMR CHEMICAL-SHIFTS OF NITROXANTHONES AND DEVELOPMENT OF ADDITIVITY RULES

H-1 and C-13 NMR chemical shifts and the homo- and heteronuclear coupl ing constants of 14 nitroxanthones are presented, Specific nitro incre ments for xanthones depending on substituent position and on the respe ctive ring carbon position and shift additivity rules were developed b y means of multiple linear regression analysis.