Synthesis of the Benzene Analogue of Vitamin A

Abstract
The successful synthesis of pure crystalline vitamin A by Arens and van Dorp1 and by Isler et al.2 opened a new field in the chemical study of vitamin A. Thus, it is possible to synthesise various analogues of vitamin A in order to establish the relationship between chemical structure and vitamin A activity. A survey of recent publications on synthetic compounds bearing modified side chains led to the conclusion that although the terminal hydroxyl group might not be of utmost importance, the length and the general skeleton of the side chain could not be altered without a complete loss of activity. (cf. Table I.)