Biologically active polycycloalkanes. 1. Antiviral adamantane derivatives.

Convenient methods for the synthesis of 1-substituted 3-adamantyl chlorides and bromides (2), 1-adamantylphenols and -cresols (3), and 1-adamantylacetic (6) as well as 1,3-adamantanediacetic (11) acids are described. Several novel derivatives were synthesized from these key intermediates: adamantylcyclohexanols (4) and -cyclohexanones (5) from adamantylphenols (3), and esters (7,12, and 22), amides (13 and 18), thioamides (9 and 16), amidine (10), nitrile (15), and amines (14 and 17) from 1-adamantanecarboxylic (19) and -acetic (6) acids and 1,3-adamantanediacetic acid (11). Some adamantylpyrimidines (24) and -purines (25 and 26) were also prepared. Antiviral activities of the compounds obtained in this work and a series of new 1-adamantyl alkyl ketones synthesized before, together with those of some known adamantane derivatives, were tested in vitro on monolayer culture of chick ambryo fibroblasts against Newcastle disease virus.