INTRODUCTION Ultraviolet and visible absorptions of organic compounds are characteristic of absorbing systems that consist of a so called chromophore group and the auxochromic groups bonded to it, rat[.]
INTRODUCTION Ultraviolet and visible absorptions of organic compounds are characteristic of absorbing systems that consist of a so-called chromophore group and the auxochromic groups bonded to it, rather than the chemical structure of the molecule as a whole For example, the ultraviolet absorption maximum of the cholestadienone isomer (I) is close to that, of (II), but entirely different from those of the other isomers, (III), (IV), and (V)o However, it is very close to the absorption maximum of a nonsteroidal, 4-methyl-6-(2,6,6-trimethyl-2-cyclohexenyl)-3,5-hexadien-2-one (VI) This is natural because the absorbing system is the same in (I), (II), and (VI), but is quite different from those of (III), (IV), and (V)0 (I) cholesta-4,6-dien-3-one (II) *2Sf 277m^ *max* 285m^